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Sample records for camera lroc images

  1. LROC - Lunar Reconnaissance Orbiter Camera

    NASA Astrophysics Data System (ADS)

    Robinson, M. S.; Eliason, E.; Hiesinger, H.; Jolliff, B. L.; McEwen, A.; Malin, M. C.; Ravine, M. A.; Thomas, P. C.; Turtle, E. P.

    2009-12-01

    The Lunar Reconnaissance Orbiter (LRO) went into lunar orbit on 23 June 2009. The LRO Camera (LROC) acquired its first lunar images on June 30 and commenced full scale testing and commissioning on July 10. The LROC consists of two narrow-angle cameras (NACs) that provide 0.5 m scale panchromatic images over a combined 5 km swath, and a wide-angle camera (WAC) to provide images at a scale of 100 m per pixel in five visible wavelength bands (415, 566, 604, 643, and 689 nm) and 400 m per pixel in two ultraviolet bands (321 nm and 360 nm) from the nominal 50 km orbit. Early operations were designed to test the performance of the cameras under all nominal operating conditions and provided a baseline for future calibrations. Test sequences included off-nadir slews to image stars and the Earth, 90° yaw sequences to collect flat field calibration data, night imaging for background characterization, and systematic mapping to test performance. LRO initially was placed into a terminator orbit resulting in images acquired under low signal conditions. Over the next three months the incidence angle at the spacecraft’s equator crossing gradually decreased towards high noon, providing a range of illumination conditions. Several hundred south polar images were collected in support of impact site selection for the LCROSS mission; details can be seen in many of the shadows. Commissioning phase images not only proved the instruments’ overall performance was nominal, but also that many geologic features of the lunar surface are well preserved at the meter-scale. Of particular note is the variety of impact-induced morphologies preserved in a near pristine state in and around kilometer-scale and larger young Copernican age impact craters that include: abundant evidence of impact melt of a variety of rheological properties, including coherent flows with surface textures and planimetric properties reflecting supersolidus (e.g., liquid melt) emplacement, blocks delicately perched on

  2. Lunar Reconnaissance Orbiter Camera (LROC) instrument overview

    USGS Publications Warehouse

    Robinson, M.S.; Brylow, S.M.; Tschimmel, M.; Humm, D.; Lawrence, S.J.; Thomas, P.C.; Denevi, B.W.; Bowman-Cisneros, E.; Zerr, J.; Ravine, M.A.; Caplinger, M.A.; Ghaemi, F.T.; Schaffner, J.A.; Malin, M.C.; Mahanti, P.; Bartels, A.; Anderson, J.; Tran, T.N.; Eliason, E.M.; McEwen, A.S.; Turtle, E.; Jolliff, B.L.; Hiesinger, H.

    2010-01-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NACs) are on the NASA Lunar Reconnaissance Orbiter (LRO). The WAC is a 7-color push-frame camera (100 and 400 m/pixel visible and UV, respectively), while the two NACs are monochrome narrow-angle linescan imagers (0.5 m/pixel). The primary mission of LRO is to obtain measurements of the Moon that will enable future lunar human exploration. The overarching goals of the LROC investigation include landing site identification and certification, mapping of permanently polar shadowed and sunlit regions, meter-scale mapping of polar regions, global multispectral imaging, a global morphology base map, characterization of regolith properties, and determination of current impact hazards.

  3. Enhancement of Spatial Resolution of the Lroc Wide Angle Camera Images

    NASA Astrophysics Data System (ADS)

    Mahanti, P.; Robinson, M. S.; Sato, H.; Awumah, A.; Henriksen, M.

    2016-06-01

    Image fusion, a popular method for resolution enhancement in Earth-based remote sensing studies involves the integration of geometric (sharpness) detail of a high-resolution panchromatic (Pan) image and the spectral information of a lower resolution multi-spectral (MS) image. Image fusion with planetary images is not as widespread as with terrestrial studies, although successful application of image fusion can lead to the generation of higher resolution MS image data. A comprehensive comparison of six image fusion algorithms in the context of lunar images is presented in this work. Performance of these algorithms is compared by visual inspection of the high-resolution multi-spectral products, derived products such as band-to-band ratio and composite images, and performance metrics with an emphasis on spectral content preservation. Enhanced MS images of the lunar surface can enable new science and maximize the science return for current and future missions.

  4. Flight Calibration of the LROC Narrow Angle Camera

    NASA Astrophysics Data System (ADS)

    Humm, D. C.; Tschimmel, M.; Brylow, S. M.; Mahanti, P.; Tran, T. N.; Braden, S. E.; Wiseman, S.; Danton, J.; Eliason, E. M.; Robinson, M. S.

    2016-04-01

    Characterization and calibration are vital for instrument commanding and image interpretation in remote sensing. The Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) takes 500 Mpixel greyscale images of lunar scenes at 0.5 meters/pixel. It uses two nominally identical line scan cameras for a larger crosstrack field of view. Stray light, spatial crosstalk, and nonlinearity were characterized using flight images of the Earth and the lunar limb. These are important for imaging shadowed craters, studying ˜1 meter size objects, and photometry respectively. Background, nonlinearity, and flatfield corrections have been implemented in the calibration pipeline. An eight-column pattern in the background is corrected. The detector is linear for DN = 600--2000 but a signal-dependent additive correction is required and applied for DN<600. A predictive model of detector temperature and dark level was developed to command dark level offset. This avoids images with a cutoff at DN=0 and minimizes quantization error in companding. Absolute radiometric calibration is derived from comparison of NAC images with ground-based images taken with the Robotic Lunar Observatory (ROLO) at much lower spatial resolution but with the same photometric angles.

  5. Initial Results of 3D Topographic Mapping Using Lunar Reconnaissance Orbiter Camera (LROC) Stereo Imagery

    NASA Astrophysics Data System (ADS)

    Li, R.; Oberst, J.; McEwen, A. S.; Archinal, B. A.; Beyer, R. A.; Thomas, P. C.; Chen, Y.; Hwangbo, J.; Lawver, J. D.; Scholten, F.; Mattson, S. S.; Howington-Kraus, A. E.; Robinson, M. S.

    2009-12-01

    The Lunar Reconnaissance Orbiter (LRO), launched June 18, 2009, carries the Lunar Reconnaissance Orbiter Camera (LROC) as one of seven remote sensing instruments on board. The camera system is equipped with a Wide Angle Camera (WAC) and two Narrow Angle Cameras (NAC) for systematic lunar surface mapping and detailed site characterization for potential landing site selection and resource identification. The LROC WAC is a pushframe camera with five 14-line by 704-sample framelets for visible light bands and two 16-line by 512-sample (summed 4x to 4 by 128) UV bands. The WAC can also acquire monochrome images with a 14-line by 1024-sample format. At the nominal 50-km orbit the visible bands ground scale is 75-m/pixel and the UV 383-m/pixel. Overlapping WAC images from adjacent orbits can be used to map topography at a scale of a few hundred meters. The two panchromatic NAC cameras are pushbroom imaging sensors each with a Cassegrain telescope of a 700-mm focal length. The two NAC cameras are aligned with a small overlap in the cross-track direction so that they cover a 5-km swath with a combined field-of-view (FOV) of 5.6°. At an altitude of 50-km, the NAC can provide panchromatic images from its 5,000-pixel linear CCD at a ground scale of 0.5-m/pixel. Calibration of the cameras was performed by using precision collimator measurements to determine the camera principal points and radial lens distortion. The orientation of the two NAC cameras is estimated by a boresight calibration using double and triple overlapping NAC images of the lunar surface. The resulting calibration results are incorporated into a photogrammetric bundle adjustment (BA), which models the LROC camera imaging geometry, in order to refine the exterior orientation (EO) parameters initially retrieved from the SPICE kernels. Consequently, the improved EO parameters can significantly enhance the quality of topographic products derived from LROC NAC imagery. In addition, an analysis of the spacecraft

  6. Characterization of previously unidentified lunar pyroclastic deposits using Lunar Reconnaissance Orbiter Camera (LROC) data

    USGS Publications Warehouse

    Gustafson, J. Olaf; Bell, James F.; Gaddis, Lisa R.R.; Hawke, B. Ray Ray; Giguere, Thomas A.

    2012-01-01

    We used a Lunar Reconnaissance Orbiter Camera (LROC) global monochrome Wide-angle Camera (WAC) mosaic to conduct a survey of the Moon to search for previously unidentified pyroclastic deposits. Promising locations were examined in detail using LROC multispectral WAC mosaics, high-resolution LROC Narrow Angle Camera (NAC) images, and Clementine multispectral (ultraviolet-visible or UVVIS) data. Out of 47 potential deposits chosen for closer examination, 12 were selected as probable newly identified pyroclastic deposits. Potential pyroclastic deposits were generally found in settings similar to previously identified deposits, including areas within or near mare deposits adjacent to highlands, within floor-fractured craters, and along fissures in mare deposits. However, a significant new finding is the discovery of localized pyroclastic deposits within floor-fractured craters Anderson E and F on the lunar farside, isolated from other known similar deposits. Our search confirms that most major regional and localized low-albedo pyroclastic deposits have been identified on the Moon down to ~100 m/pix resolution, and that additional newly identified deposits are likely to be either isolated small deposits or additional portions of discontinuous, patchy deposits.

  7. Photometric normalization of LROC WAC images

    NASA Astrophysics Data System (ADS)

    Sato, H.; Boyd, A. K.; Denevi, B. W.; Robinson, M. S.; Hapke, B. W.; McEwen, A. S.; Humm, D. C.; LROC Science Operations Team

    2011-12-01

    Monthly global Lunar Reconnaissance Orbiter (LRO) Wide Angle Camera (WAC) observations of the Moon, acquired with varying emission and incidence angles, enable the precise derivation of spatially resolved Hapke photometric parameters [1]. The WAC global mosaics are stacked in a time series to enable phase curve fitting using a tile-by-tile method, with a wide range of phase angle in each tile. Tile-by-tile calculations provide photometric parameters for each tile (currently 1° by 1° from 80° to -80° latitude), resulting in resolved near-global photometric parameter maps (w, xi, Bco, and hc)[2]. Incidence, emission, and phase angles are computed using a new WAC stereometric digital terrain model (100 m/pixel)[3]. In the tile-by-tile method, we obtain low phase observations only near the equator resulting in an inability to accurately estimate Bco at higher latitudes (Hapke parameter controls the y-intercept of phase curve). We interpolated Bco poleward of +/- 5° latitudes, using a negative correlation between w and Bco observed in the equator +/- 5° latitudes. This interpolation method can decrease one free parameter, resulting in short calculation time and much less failed tiles. The normalized image using this parameter map shows almost no tile boundary, which shows that the tile-by-tile method works well. After the tile-by-tile method was applied with twenty months of data over a full range of beta angle, we observed an I/F offset with time. This offset results in reflectance differences at month-to-month boundaries in a global mosaic constructed from sequences acquired over different months (constructed to minimize incidence angle differences as a function of latitude). After significant tests of any possible parameters controlling the residual I/F value, incidence angle was revealed to be a dominant factor, indicating that the photometry model may not completely accounting for incidence angle. The main function dealing with incidence angle is the Lommel

  8. Photometric normalization of LROC WAC images

    NASA Astrophysics Data System (ADS)

    Sato, H.; Denevi, B.; Robinson, M. S.; Hapke, B. W.; McEwen, A. S.; LROC Science Team

    2010-12-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) acquires near global coverage on a monthly basis. The WAC is a push frame sensor with a 90° field of view (FOV) in BW mode and 60° FOV in 7-color mode (320 nm to 689 nm). WAC images are acquired during each orbit in 10° latitude segments with cross track coverage of ~50 km. Before mosaicking, WAC images are radiometrically calibrated to remove instrumental artifacts and to convert at sensor radiance to I/F. Images are also photometrically normalized to common viewing and illumination angles (30° phase), a challenge due to the wide angle nature of the WAC where large differences in phase angle are observed in a single image line (±30°). During a single month the equatorial incidence angle drifts about 28° and over the course of ~1 year the lighting completes a 360° cycle. The light scattering properties of the lunar surface depend on incidence(i), emission(e), and phase(p) angles as well as soil properties such as single-scattering albedo and roughness that vary with terrain type and state of maturity [1]. We first tested a Lommel-Seeliger Correction (LSC) [cos(i)/(cos(i) + cos(e))] [2] with a phase function defined by an exponential decay plus 4th order polynomial term [3] which did not provide an adequate solution. Next we employed a LSC with an exponential 2nd order decay phase correction that was an improvement, but still exhibited unacceptable frame-to-frame residuals. In both cases we fitted the LSC I/F vs. phase angle to derive the phase corrections. To date, the best results are with a lunar-lambert function [4] with exponential 2nd order decay phase correction (LLEXP2) [(A1exp(B1p)+A2exp(B2p)+A3) * cos(i)/(cos(e) + cos(i)) + B3cos(i)]. We derived the parameters for the LLEXP2 from repeat imaging of a small region and then corrected that region with excellent results. When this correction was applied to the whole Moon the results were less than optimal - no surprise given the

  9. Investigating at the Moon With new Eyes: The Lunar Reconnaissance Orbiter Mission Camera (LROC)

    NASA Astrophysics Data System (ADS)

    Hiesinger, H.; Robinson, M. S.; McEwen, A. S.; Turtle, E. P.; Eliason, E. M.; Jolliff, B. L.; Malin, M. C.; Thomas, P. C.

    The Lunar Reconnaissance Orbiter Mission Camera (LROC) H. Hiesinger (1,2), M.S. Robinson (3), A.S. McEwen (4), E.P. Turtle (4), E.M. Eliason (4), B.L. Jolliff (5), M.C. Malin (6), and P.C. Thomas (7) (1) Brown Univ., Dept. of Geological Sciences, Providence RI 02912, Harald_Hiesinger@brown.edu, (2) Westfaelische Wilhelms-University, (3) Northwestern Univ., (4) LPL, Univ. of Arizona, (5) Washington Univ., (6) Malin Space Science Systems, (7) Cornell Univ. The Lunar Reconnaissance Orbiter (LRO) mission is scheduled for launch in October 2008 as a first step to return humans to the Moon by 2018. The main goals of the Lunar Reconnaissance Orbiter Camera (LROC) are to: 1) assess meter and smaller- scale features for safety analyses for potential lunar landing sites near polar resources, and elsewhere on the Moon; and 2) acquire multi-temporal images of the poles to characterize the polar illumination environment (100 m scale), identifying regions of permanent shadow and permanent or near permanent illumination over a full lunar year. In addition, LROC will return six high-value datasets such as 1) meter-scale maps of regions of permanent or near permanent illumination of polar massifs; 2) high resolution topography through stereogrammetric and photometric stereo analyses for potential landing sites; 3) a global multispectral map in 7 wavelengths (300-680 nm) to characterize lunar resources, in particular ilmenite; 4) a global 100-m/pixel basemap with incidence angles (60-80 degree) favorable for morphologic interpretations; 5) images of a variety of geologic units at sub-meter resolution to investigate physical properties and regolith variability; and 6) meter-scale coverage overlapping with Apollo Panoramic images (1-2 m/pixel) to document the number of small impacts since 1971-1972, to estimate hazards for future surface operations. LROC consists of two narrow-angle cameras (NACs) which will provide 0.5-m scale panchromatic images over a 5-km swath, a wide

  10. Extracting Accurate and Precise Topography from Lroc Narrow Angle Camera Stereo Observations

    NASA Astrophysics Data System (ADS)

    Henriksen, M. R.; Manheim, M. R.; Speyerer, E. J.; Robinson, M. S.; LROC Team

    2016-06-01

    The Lunar Reconnaissance Orbiter Camera (LROC) includes two identical Narrow Angle Cameras (NAC) that acquire meter scale imaging. Stereo observations are acquired by imaging from two or more orbits, including at least one off-nadir slew. Digital terrain models (DTMs) generated from the stereo observations are controlled to Lunar Orbiter Laser Altimeter (LOLA) elevation profiles. With current processing methods, digital terrain models (DTM) have absolute accuracies commensurate than the uncertainties of the LOLA profiles (~10 m horizontally and ~1 m vertically) and relative horizontal and vertical precisions better than the pixel scale of the DTMs (2 to 5 m). The NAC stereo pairs and derived DTMs represent an invaluable tool for science and exploration purposes. We computed slope statistics from 81 highland and 31 mare DTMs across a range of baselines. Overlapping DTMs of single stereo sets were also combined to form larger area DTM mosaics, enabling detailed characterization of large geomorphic features and providing a key resource for future exploration planning. Currently, two percent of the lunar surface is imaged in NAC stereo and continued acquisition of stereo observations will serve to strengthen our knowledge of the Moon and geologic processes that occur on all the terrestrial planets.

  11. Exploring the Moon at High-Resolution: First Results From the Lunar Reconnaissance Orbiter Camera (LROC)

    NASA Astrophysics Data System (ADS)

    Robinson, Mark; Hiesinger, Harald; McEwen, Alfred; Jolliff, Brad; Thomas, Peter C.; Turtle, Elizabeth; Eliason, Eric; Malin, Mike; Ravine, A.; Bowman-Cisneros, Ernest

    The Lunar Reconnaissance Orbiter (LRO) spacecraft was launched on an Atlas V 401 rocket from the Cape Canaveral Air Force Station Launch Complex 41 on June 18, 2009. After spending four days in Earth-Moon transit, the spacecraft entered a three month commissioning phase in an elliptical 30×200 km orbit. On September 15, 2009, LRO began its planned one-year nominal mapping mission in a quasi-circular 50 km orbit. A multi-year extended mission in a fixed 30×200 km orbit is optional. The Lunar Reconnaissance Orbiter Camera (LROC) consists of a Wide Angle Camera (WAC) and two Narrow Angle Cameras (NACs). The WAC is a 7-color push-frame camera, which images the Moon at 100 and 400 m/pixel in the visible and UV, respectively, while the two NACs are monochrome narrow-angle linescan imagers with 0.5 m/pixel spatial resolution. LROC was specifically designed to address two of the primary LRO mission requirements and six other key science objectives, including 1) assessment of meter-and smaller-scale features in order to select safe sites for potential lunar landings near polar resources and elsewhere on the Moon; 2) acquire multi-temporal synoptic 100 m/pixel images of the poles during every orbit to unambiguously identify regions of permanent shadow and permanent or near permanent illumination; 3) meter-scale mapping of regions with permanent or near-permanent illumination of polar massifs; 4) repeat observations of potential landing sites and other regions to derive high resolution topography; 5) global multispectral observations in seven wavelengths to characterize lunar resources, particularly ilmenite; 6) a global 100-m/pixel basemap with incidence angles (60° -80° ) favorable for morphological interpretations; 7) sub-meter imaging of a variety of geologic units to characterize their physical properties, the variability of the regolith, and other key science questions; 8) meter-scale coverage overlapping with Apollo-era panoramic images (1-2 m/pixel) to document

  12. Exploring the Moon at High-Resolution: First Results From the Lunar Reconnaissance Orbiter Camera (LROC)

    NASA Astrophysics Data System (ADS)

    Robinson, Mark; Hiesinger, Harald; McEwen, Alfred; Jolliff, Brad; Thomas, Peter C.; Turtle, Elizabeth; Eliason, Eric; Malin, Mike; Ravine, A.; Bowman-Cisneros, Ernest

    The Lunar Reconnaissance Orbiter (LRO) spacecraft was launched on an Atlas V 401 rocket from the Cape Canaveral Air Force Station Launch Complex 41 on June 18, 2009. After spending four days in Earth-Moon transit, the spacecraft entered a three month commissioning phase in an elliptical 30×200 km orbit. On September 15, 2009, LRO began its planned one-year nominal mapping mission in a quasi-circular 50 km orbit. A multi-year extended mission in a fixed 30×200 km orbit is optional. The Lunar Reconnaissance Orbiter Camera (LROC) consists of a Wide Angle Camera (WAC) and two Narrow Angle Cameras (NACs). The WAC is a 7-color push-frame camera, which images the Moon at 100 and 400 m/pixel in the visible and UV, respectively, while the two NACs are monochrome narrow-angle linescan imagers with 0.5 m/pixel spatial resolution. LROC was specifically designed to address two of the primary LRO mission requirements and six other key science objectives, including 1) assessment of meter-and smaller-scale features in order to select safe sites for potential lunar landings near polar resources and elsewhere on the Moon; 2) acquire multi-temporal synoptic 100 m/pixel images of the poles during every orbit to unambiguously identify regions of permanent shadow and permanent or near permanent illumination; 3) meter-scale mapping of regions with permanent or near-permanent illumination of polar massifs; 4) repeat observations of potential landing sites and other regions to derive high resolution topography; 5) global multispectral observations in seven wavelengths to characterize lunar resources, particularly ilmenite; 6) a global 100-m/pixel basemap with incidence angles (60° -80° ) favorable for morphological interpretations; 7) sub-meter imaging of a variety of geologic units to characterize their physical properties, the variability of the regolith, and other key science questions; 8) meter-scale coverage overlapping with Apollo-era panoramic images (1-2 m/pixel) to document

  13. Occurrence probability of slopes on the lunar surface: Estimate by the shaded area percentage in the LROC NAC images

    NASA Astrophysics Data System (ADS)

    Abdrakhimov, A. M.; Basilevsky, A. T.; Ivanov, M. A.; Kokhanov, A. A.; Karachevtseva, I. P.; Head, J. W.

    2015-09-01

    The paper describes the method of estimating the distribution of slopes by the portion of shaded areas measured in the images acquired at different Sun elevations. The measurements were performed for the benefit of the Luna-Glob Russian mission. The western ellipse for the spacecraft landing in the crater Bogus-lawsky in the southern polar region of the Moon was investigated. The percentage of the shaded area was measured in the images acquired with the LROC NAC camera with a resolution of ~0.5 m. Due to the close vicinity of the pole, it is difficult to build digital terrain models (DTMs) for this region from the LROC NAC images. Because of this, the method described has been suggested. For the landing ellipse investigated, 52 LROC NAC images obtained at the Sun elevation from 4° to 19° were used. In these images the shaded portions of the area were measured, and the values of these portions were transferred to the values of the occurrence of slopes (in this case, at the 3.5-m baseline) with the calibration by the surface characteristics of the Lunokhod-1 study area. For this area, the digital terrain model of the ~0.5-m resolution and 13 LROC NAC images obtained at different elevations of the Sun are available. From the results of measurements and the corresponding calibration, it was found that, in the studied landing ellipse, the occurrence of slopes gentler than 10° at the baseline of 3.5 m is 90%, while it is 9.6, 5.7, and 3.9% for the slopes steeper than 10°, 15°, and 20°, respectively. Obviously, this method can be recommended for application if there is no DTM of required granularity for the regions of interest, but there are high-resolution images taken at different elevations of the Sun.

  14. GLD100: The near-global lunar 100 m raster DTM from LROC WAC stereo image data

    NASA Astrophysics Data System (ADS)

    Scholten, F.; Oberst, J.; Matz, K.-D.; Roatsch, T.; Wählisch, M.; Speyerer, E. J.; Robinson, M. S.

    2012-03-01

    We derived near-global lunar topography from stereo image data acquired by the Wide-angle Camera (WAC) of the Lunar Reconnaissance Orbiter Camera (LROC) system. From polar orbit tracks, the LROC WAC provides image data with a mean ground resolution at nadir of 75 m/pixel with substantial cross-track stereo overlap. WAC stereo images from the one-year nominal mission and the first months of the science mission phase are combined to produce a near-global digital terrain model (DTM) with a pixel spacing of 100 m, the Global Lunar DTM 100 m, or “GLD100.” It covers 79°S to 79°N latitudes, 98.2% of the entire lunar surface. We compare the GLD100 with results from previous stereo and altimetry-based products, particularly with the Lunar Orbiter Laser Altimeter (LOLA) altimetry, which is the current topographic reference for the Moon. We describe typical characteristics of the GLD100 and, based upon the comparison to the LOLA data set, assess its vertical and lateral resolution and accuracy. We conclude that the introduced first version of the stereo-based GLD100 is a valuable topographic representation of the lunar surface, complementary to the LOLA altimetry data set. Further improvements can be expected from continuative investigations.

  15. The Search for Lunar Lobate Scarps Using Images from the Lunar Reconnaissance Orbiter Camera

    NASA Astrophysics Data System (ADS)

    Banks, M. E.; Watters, T. R.; Robinson, M. S.; Bell, J. F.; Pritchard, M. E.; Williams, N. R.; Daud, K.; Lroc Team

    2011-03-01

    A search for previously undetected lobate scarps was conducted using images from the Lunar Reconnaissance Orbiter Camera. To date, previously undetected lobate scarps have been identified in LROC images and mosaics in 73 different locations.

  16. Photometric parameter maps of the Moon derived from LROC WAC images

    NASA Astrophysics Data System (ADS)

    Sato, H.; Robinson, M. S.; Hapke, B. W.; Denevi, B. W.; Boyd, A. K.

    2013-12-01

    Spatially resolved photometric parameter maps were computed from 21 months of Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) images. Due to a 60° field-of-view (FOV), the WAC achieves nearly global coverage of the Moon each month with more than 50% overlap from orbit-to-orbit. From the repeat observations at various viewing and illumination geometries, we calculated Hapke bidirectional reflectance model parameters [1] for 1°x1° "tiles" from 70°N to 70°S and 0°E to 360°E. About 66,000 WAC images acquired from February 2010 to October 2011 were converted from DN to radiance factor (I/F) though radiometric calibration, partitioned into gridded tiles, and stacked in a time series (tile-by-tile method [2]). Lighting geometries (phase, incidence, emission) were computed using the WAC digital terrain model (100 m/pixel) [3]. The Hapke parameters were obtained by model fitting against I/F within each tile. Among the 9 parameters of the Hapke model, we calculated 3 free parameters (w, b, and hs) by setting constant values for 4 parameters (Bco=0, hc=1, θ, φ=0) and interpolating 2 parameters (c, Bso). In this simplification, we ignored the Coherent Backscatter Opposition Effect (CBOE) to avoid competing CBOE and Shadow Hiding Opposition Effect (SHOE). We also assumed that surface regolith porosity is uniform across the Moon. The roughness parameter (θ) was set to an averaged value from the equator (× 3°N). The Henyey-Greenstein double lobe function (H-G2) parameter (c) was given by the 'hockey stick' relation [4] (negative correlation) between b and c based on laboratory measurements. The amplitude of SHOE (Bso) was given by the correlation between w and Bso at the equator (× 3°N). Single scattering albedo (w) is strongly correlated to the photometrically normalized I/F, as expected. The c shows an inverse trend relative to b due to the 'hockey stick' relation. The parameter c is typically low for the maria (0.08×0.06) relative to the

  17. Secondary Craters and the Size-Velocity Distribution of Ejected Fragments around Lunar Craters Measured Using LROC Images

    NASA Astrophysics Data System (ADS)

    Singer, K. N.; Jolliff, B. L.; McKinnon, W. B.

    2013-12-01

    Title: Secondary Craters and the Size-Velocity Distribution of Ejected Fragments around Lunar Craters Measured Using LROC Images Authors: Kelsi N. Singer1, Bradley L. Jolliff1, and William B. McKinnon1 Affiliations: 1. Earth and Planetary Sciences, Washington University in St Louis, St. Louis, MO, United States. We report results from analyzing the size-velocity distribution (SVD) of secondary crater forming fragments from the 93 km diameter Copernicus impact. We measured the diameters of secondary craters and their distances from Copernicus using LROC Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) image data. We then estimated the velocity and size of the ejecta fragment that formed each secondary crater from the range equation for a ballistic trajectory on a sphere and Schmidt-Holsapple scaling relations. Size scaling was carried out in the gravity regime for both non-porous and porous target material properties. We focus on the largest ejecta fragments (dfmax) at a given ejection velocity (υej) and fit the upper envelope of the SVD using quantile regression to an equation of the form dfmax = A*υej ^- β. The velocity exponent, β, describes how quickly fragment sizes fall off with increasing ejection velocity during crater excavation. For Copernicus, we measured 5800 secondary craters, at distances of up to 700 km (15 crater radii), corresponding to an ejecta fragment velocity of approximately 950 m/s. This mapping only includes secondary craters that are part of a radial chain or cluster. The two largest craters in chains near Copernicus that are likely to be secondaries are 6.4 and 5.2 km in diameter. We obtained a velocity exponent, β, of 2.2 × 0.1 for a non-porous surface. This result is similar to Vickery's [1987, GRL 14] determination of β = 1.9 × 0.2 for Copernicus using Lunar Orbiter IV data. The availability of WAC 100 m/pix global mosaics with illumination geometry optimized for morphology allows us to update and extend the work of Vickery

  18. LROC Advances in Lunar Science

    NASA Astrophysics Data System (ADS)

    Robinson, M. S.

    2012-12-01

    Since entering orbit in 2009 the Lunar Reconnaissance Orbiter Camera (LROC) has acquired over 700,000 Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) images of the Moon. This new image collection is fueling research into the origin and evolution of the Moon. NAC images revealed a volcanic complex 35 x 25 km (60N, 100E), between Compton and Belkovich craters (CB). The CB terrain sports volcanic domes and irregular depressed areas (caldera-like collapses). The volcanic complex corresponds to an area of high-silica content (Diviner) and high Th (Lunar Prospector). A low density of impact craters on the CB complex indicates a relatively young age. The LROC team mapped over 150 volcanic domes and 90 volcanic cones in the Marius Hills (MH), many of which were not previously identified. Morphology and compositional estimates (Diviner) indicate that MH domes are silica poor, and are products of low-effusion mare lavas. Impact melt deposits are observed with Copernican impact craters (>10 km) on exterior ejecta, the rim, inner wall, and crater floors. Preserved impact melt flow deposits are observed around small craters (25 km diam.), and estimated melt volumes exceed predictions. At these diameters the amount of melt predicted is small, and melt that is produced is expected to be ejected from the crater. However, we observe well-defined impact melt deposits on the floor of highland craters down to 200 m diameter. A globally distributed population of previously undetected contractional structures were discovered. Their crisp appearance and associated impact crater populations show that they are young landforms (<1 Ga). NAC images also revealed small extensional troughs. Crosscutting relations with small-diameter craters and depths as shallow as 1 m indicate ages <50 Ma. These features place bounds on the amount of global radial contraction and the level of compressional stress in the crust. WAC temporal coverage of the poles allowed quantification of highly

  19. Using LROC analysis to evaluate detection accuracy of microcalcification clusters imaged with flat-panel CT mammography

    NASA Astrophysics Data System (ADS)

    Gong, Xing; Glick, Stephen J.; Vedula, Aruna A.

    2004-05-01

    The purpose of this study is to investigate the detectability of microcalcification clusters (MCCs) using CT mammography with a flat-panel detector. Compared with conventional mammography, CT mammography can provide improved discrimination between malignant and benign cases as it can provide the radiologist with more accurate morphological information on MCCs. In this study, two aspects of MCC detection with flat-panel CT mammography were examined: (1) the minimal size of MCCs detectable with mean glandular dose (MGD) used in conventional mammography; (2) the effect of different detector pixel size on the detectability of MCCs. A realistic computer simulation modeling x-ray transport through the breast, as well as both signal and noise propagation through the flat-panel imager, was developed to investigate these questions. Microcalcifications were simulated as calcium carbonate spheres with diameters set at the levels of 125, 150 and 175 μm. Each cluster consisted of 10 spheres spread randomly in a 6×6 mm2 region of interest (ROI) and the detector pixel size was set to 100×100, 200×200, or 300×300μm2. After reconstructing 100 projection sets for each case (half with signal present) with the cone-beam Feldkamp (FDK) algorithm, a localization receiver operating characteristic (LROC) study was conducted to evaluate the detectability of MCCs. Five observers chose the locations of cluster centers with correspondent confidence ratings. The average area under the LROC curve suggested that the 175 μm MCCs can be detected at a high level of confidence. Results also indicate that flat-panel detectors with pixel size of 200×200 μm2 are appropriate for detecting small targets, such as MCCs.

  20. Dry imaging cameras

    PubMed Central

    Indrajit, IK; Alam, Aftab; Sahni, Hirdesh; Bhatia, Mukul; Sahu, Samaresh

    2011-01-01

    Dry imaging cameras are important hard copy devices in radiology. Using dry imaging camera, multiformat images of digital modalities in radiology are created from a sealed unit of unexposed films. The functioning of a modern dry camera, involves a blend of concurrent processes, in areas of diverse sciences like computers, mechanics, thermal, optics, electricity and radiography. Broadly, hard copy devices are classified as laser and non laser based technology. When compared with the working knowledge and technical awareness of different modalities in radiology, the understanding of a dry imaging camera is often superficial and neglected. To fill this void, this article outlines the key features of a modern dry camera and its important issues that impact radiology workflow. PMID:21799589

  1. Spacecraft camera image registration

    NASA Technical Reports Server (NTRS)

    Kamel, Ahmed A. (Inventor); Graul, Donald W. (Inventor); Chan, Fred N. T. (Inventor); Gamble, Donald W. (Inventor)

    1987-01-01

    A system for achieving spacecraft camera (1, 2) image registration comprises a portion external to the spacecraft and an image motion compensation system (IMCS) portion onboard the spacecraft. Within the IMCS, a computer (38) calculates an image registration compensation signal (60) which is sent to the scan control loops (84, 88, 94, 98) of the onboard cameras (1, 2). At the location external to the spacecraft, the long-term orbital and attitude perturbations on the spacecraft are modeled. Coefficients (K, A) from this model are periodically sent to the onboard computer (38) by means of a command unit (39). The coefficients (K, A) take into account observations of stars and landmarks made by the spacecraft cameras (1, 2) themselves. The computer (38) takes as inputs the updated coefficients (K, A) plus synchronization information indicating the mirror position (AZ, EL) of each of the spacecraft cameras (1, 2), operating mode, and starting and stopping status of the scan lines generated by these cameras (1, 2), and generates in response thereto the image registration compensation signal (60). The sources of periodic thermal errors on the spacecraft are discussed. The system is checked by calculating measurement residuals, the difference between the landmark and star locations predicted at the external location and the landmark and star locations as measured by the spacecraft cameras (1, 2).

  2. Selective-imaging camera

    NASA Astrophysics Data System (ADS)

    Szu, Harold; Hsu, Charles; Landa, Joseph; Cha, Jae H.; Krapels, Keith A.

    2015-05-01

    How can we design cameras that image selectively in Full Electro-Magnetic (FEM) spectra? Without selective imaging, we cannot use, for example, ordinary tourist cameras to see through fire, smoke, or other obscurants contributing to creating a Visually Degraded Environment (VDE). This paper addresses a possible new design of selective-imaging cameras at firmware level. The design is consistent with physics of the irreversible thermodynamics of Boltzmann's molecular entropy. It enables imaging in appropriate FEM spectra for sensing through the VDE, and displaying in color spectra for Human Visual System (HVS). We sense within the spectra the largest entropy value of obscurants such as fire, smoke, etc. Then we apply a smart firmware implementation of Blind Sources Separation (BSS) to separate all entropy sources associated with specific Kelvin temperatures. Finally, we recompose the scene using specific RGB colors constrained by the HVS, by up/down shifting Planck spectra at each pixel and time.

  3. Photometric characterization of the Chang'e-3 landing site using LROC NAC images

    NASA Astrophysics Data System (ADS)

    Clegg-Watkins, R. N.; Jolliff, B. L.; Boyd, A.; Robinson, M. S.; Wagner, R.; Stopar, J. D.; Plescia, J. B.; Speyerer, E. J.

    2016-07-01

    China's robotic Chang'e-3 spacecraft, carrying the Yutu rover, touched down in Mare Imbrium on the lunar surface on 14 December 2013. The Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) imaged the site both before and after landing. Multi-temporal NAC images taken before and after the landing, phase-ratio images made from NAC images taken after the landing, and Hapke photometric techniques were used to evaluate surface changes caused by the disturbance of regolith at the landing site (blast zone) by the descent engines of the Chang'e-3 spacecraft. The reflectance of the landing site increased by 10 ± 1% (from I/F = 0.040 to 0.044 at 30° phase angle) as a result of the landing, a value similar to reflectance increases estimated for the Apollo, Luna, and Surveyor landing sites. The spatial extent of the disturbed area at the Chang'e-3 landing site, 2530 m2, also falls close to what is predicted on the basis of correlations between lander mass, thrust, and blast zone areas for the historic landed missions. A multi-temporal ratio image of the Chang'e-3 landing site reveals a main blast zone (slightly elongate in the N-S direction; ∼75 m across N-S and ∼43 m across in the E-W direction) and an extended diffuse, irregular halo that is less reflective than the main blast zone (extending ∼40-50 m in the N-S direction and ∼10-15 m in the E-W direction beyond the main blast zone). The N-S elongation of the blast zone likely resulted from maneuvering during hazard avoidance just prior to landing. The phase-ratio image reveals that the blast zone is less backscattering than surrounding undisturbed areas. The similarities in magnitude of increased reflectance between the Chang'e-3 landing site and the Surveyor, Apollo, and Luna landing sites suggest that lunar soil reflectance changes caused by interaction with rocket exhaust are not significantly altered over a period of 40-50 years. The reflectance changes are independent of regolith composition

  4. Apollo 17 Landing Site: A Cartographic Investigation of the Taurus-Littrow Valley Based on LROC NAC Imagery

    NASA Astrophysics Data System (ADS)

    Haase, I.; Wählisch, M.; Gläser, P.; Oberst, J.; Robinson, M. S.

    2014-04-01

    A Digital Terrain Model (DTM) of the Taurus- Littrow Valley with a 1.5 m/pixel resolution was derived from high resolution stereo images of the Lunar Reconnaissance Orbiter Narrow Angle Camera (LROC NAC) [1]. It was used to create a controlled LROC NAC ortho-mosaic with a pixel size of 0.5 m on the ground. Covering the entire Apollo 17 exploration site, it allows for determining accurate astronaut and surface feature positions along the astronauts' traverses when integrating historic Apollo surface photography to our analysis.

  5. Imaging phoswich anger camera

    NASA Astrophysics Data System (ADS)

    Manchanda, R. K.; Sood, R. K.

    1991-08-01

    High angular resolution and low background are the primary requisites for detectors for future astronomy experiments in the low energy gamma-ray region. Scintillation counters are still the only available large area detector for studies in this energy range. Preliminary details of a large area phoswich anger camera designed for coded aperture imaging is described and its background and position characteristics are discussed.

  6. Satellite camera image navigation

    NASA Technical Reports Server (NTRS)

    Kamel, Ahmed A. (Inventor); Graul, Donald W. (Inventor); Savides, John (Inventor); Hanson, Charles W. (Inventor)

    1987-01-01

    Pixels within a satellite camera (1, 2) image are precisely located in terms of latitude and longitude on a celestial body, such as the earth, being imaged. A computer (60) on the earth generates models (40, 50) of the satellite's orbit and attitude, respectively. The orbit model (40) is generated from measurements of stars and landmarks taken by the camera (1, 2), and by range data. The orbit model (40) is an expression of the satellite's latitude and longitude at the subsatellite point, and of the altitude of the satellite, as a function of time, using as coefficients (K) the six Keplerian elements at epoch. The attitude model (50) is based upon star measurements taken by each camera (1, 2). The attitude model (50) is a set of expressions for the deviations in a set of mutually orthogonal reference optical axes (x, y, z) as a function of time, for each camera (1, 2). Measured data is fit into the models (40, 50) using a walking least squares fit algorithm. A transformation computer (66 ) transforms pixel coordinates as telemetered by the camera (1, 2) into earth latitude and longitude coordinates, using the orbit and attitude models (40, 50).

  7. Neutron Imaging Camera

    NASA Technical Reports Server (NTRS)

    Hunter, Stanley; deNolfo, G. A.; Barbier, L. M.; Link, J. T.; Son, S.; Floyd, S. R.; Guardala, N.; Skopec, M.; Stark, B.

    2008-01-01

    The Neutron Imaging Camera (NIC) is based on the Three-dimensional Track Imager (3DTI) technology developed at GSFC for gamma-ray astrophysics applications. The 3-DTI, a large volume time-projection chamber, provides accurate, approximately 0.4 mm resolution, 3-D tracking of charged particles. The incident direction of fast neutrons, En > 0.5 MeV, are reconstructed from the momenta and energies of the proton and triton fragments resulting from (sup 3)He(n,p) (sup 3)H interactions in the 3-DTI volume. The performance of the NIC from laboratory and accelerator tests is presented.

  8. Image Sensors Enhance Camera Technologies

    NASA Technical Reports Server (NTRS)

    2010-01-01

    In the 1990s, a Jet Propulsion Laboratory team led by Eric Fossum researched ways of improving complementary metal-oxide semiconductor (CMOS) image sensors in order to miniaturize cameras on spacecraft while maintaining scientific image quality. Fossum s team founded a company to commercialize the resulting CMOS active pixel sensor. Now called the Aptina Imaging Corporation, based in San Jose, California, the company has shipped over 1 billion sensors for use in applications such as digital cameras, camera phones, Web cameras, and automotive cameras. Today, one of every three cell phone cameras on the planet feature Aptina s sensor technology.

  9. Computer-Assisted Detection of Collapse Pits in LROC NAC Images

    NASA Astrophysics Data System (ADS)

    Wagner, R. V.; Robinson, M. S.

    2012-12-01

    Pits in mare basalts and impact melt deposits provide unique environments for human shelters and preservation of geologic information. Due to their steep walls, pits are most distinguishable when the Sun is high (pit walls are casting shadows and impact crater walls are not). Because of the large number of NAC images acquired every day (>350), each typically with 5000 samples and 52,224 lines, it is not feasible to carefully search each image manually, so we developed a shadow detection algorithm (Pitscan) which analyzes an image in thirty seconds. It locates blocks of pixels that are below a digital number (DN) cutoff value, indicating that the block of pixels is "in shadow", and then runs a DN profile in the direction of solar lighting, comparing average DN values of the up-Sun and down-Sun sides. If the up-Sun average DN is higher than the down-Sun average, the shadow is assumed to be from a positive relief feature, and ignored. Otherwise, Pitscan saves a 200 x 200 pixel sub-image for later manual review. The algorithm currently generates ~150 false positives for each successful pit identification. This number would be unacceptable for an algorithm designed to catalog a common feature, but since the logic is merely intended to assist humans in locating an unusual type of feature, the false alarm rate is acceptable, and the current version allows a human to effectively check 10,000 NAC images for pits (over 2500 gigapixels) per hour. The false negative rate is not yet known, however Pitscan detected every pit in a test on a small subset of the images known to contain pits. Pitscan is only effective when the Sun is within 50° of the zenith. When the Sun is closer to the horizon crater walls often cast shadows, resulting in unacceptable numbers of false positives. Due to the Sun angle limit, only regions within 50° latitude of the equator are searchable. To date, 25.42% of the Moon has been imaged within this constraint. Early versions of Pitscan found more than

  10. Neutron Imaging Camera

    NASA Technical Reports Server (NTRS)

    Hunter, Stanley D.; DeNolfo, Georgia; Floyd, Sam; Krizmanic, John; Link, Jason; Son, Seunghee; Guardala, Noel; Skopec, Marlene; Stark, Robert

    2008-01-01

    We describe the Neutron Imaging Camera (NIC) being developed for DTRA applications by NASA/GSFC and NSWC/Carderock. The NIC is based on the Three-dimensional Track Imager (3-DTI) technology developed at GSFC for gamma-ray astrophysics applications. The 3-DTI, a large volume time-projection chamber, provides accurate, approximately 0.4 mm resolution. 3-D tracking of charged particles. The incident direction of fast neutrons, E(sub N) > 0.5 MeV. arc reconstructed from the momenta and energies of the proton and triton fragments resulting from 3He(n,p)3H interactions in the 3-DTI volume. We present angular and energy resolution performance of the NIC derived from accelerator tests.

  11. Geometric Calibration of the Clementine UVVIS Camera Using Images Acquired by the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Speyerer, E. J.; Wagner, R. V.; Robinson, M. S.

    2016-06-01

    The Clementine UVVIS camera returned over half a million images while in orbit around the Moon in 1994. Since the Clementine mission, our knowledge of lunar topography, gravity, and the location of features on the surface has vastly improved with the success of the Gravity Recovery and Interior Laboratory (GRAIL) mission and ongoing Lunar Reconnaissance Orbiter (LRO) mission. In particular, the Lunar Reconnaissance Orbiter Camera (LROC) has returned over a million images of the Moon since entering orbit in 2009. With the aid of improved ephemeris and on-orbit calibration, the LROC team created a series of precise and accurate global maps. With the updated reference frame, older lunar maps, such as those generated from Clementine UVVIS images, are misaligned making cross-mission analysis difficult. In this study, we use feature-based matching routines to refine and recalibrate the interior and exterior orientation parameters of the Clementine UVVIS camera. After applying these updates and rigorous orthorectification, we are able generate precise and accurate maps from UVVIS images to help support lunar science and future cross-mission investigations.

  12. Height-to-diameter ratios of moon rocks from analysis of Lunokhod-1 and -2 and Apollo 11-17 panoramas and LROC NAC images

    NASA Astrophysics Data System (ADS)

    Demidov, N. E.; Basilevsky, A. T.

    2014-09-01

    An analysis is performed of 91 panoramic photographs taken by Lunokhod-1 and -2, 17 panoramic images composed of photographs taken by Apollo 11-15 astronauts, and six LROC NAC photographs. The results are used to measure the height-to-visible-diameter ( h/ d) and height-to-maximum-diameter ( h/ D) ratios for lunar rocks at three highland and three mare sites on the Moon. The average h/ d and h/ D for the six sites are found to be indistinguishable at a significance level of 95%. Therefore, our estimates for the average h/ d = 0.6 ± 0.03 and h/ D = 0.54 ± 0.03 on the basis of 445 rocks are applicable for the entire Moon's surface. Rounding off, an h/ D ratio of ≈0.5 is suggested for engineering models of the lunar surface. The ratios between the long, medium, and short axes of the lunar rocks are found to be similar to those obtained in high-velocity impact experiments for different materials. It is concluded, therefore, that the degree of penetration of the studied lunar rocks into the regolith is negligible, and micrometeorite abrasion and other factors do not dominate in the evolution of the shape of lunar rocks.

  13. Full Stokes polarization imaging camera

    NASA Astrophysics Data System (ADS)

    Vedel, M.; Breugnot, S.; Lechocinski, N.

    2011-10-01

    Objective and background: We present a new version of Bossa Nova Technologies' passive polarization imaging camera. The previous version was performing live measurement of the Linear Stokes parameters (S0, S1, S2), and its derivatives. This new version presented in this paper performs live measurement of Full Stokes parameters, i.e. including the fourth parameter S3 related to the amount of circular polarization. Dedicated software was developed to provide live images of any Stokes related parameters such as the Degree Of Linear Polarization (DOLP), the Degree Of Circular Polarization (DOCP), the Angle Of Polarization (AOP). Results: We first we give a brief description of the camera and its technology. It is a Division Of Time Polarimeter using a custom ferroelectric liquid crystal cell. A description of the method used to calculate Data Reduction Matrix (DRM)5,9 linking intensity measurements and the Stokes parameters is given. The calibration was developed in order to maximize the condition number of the DRM. It also allows very efficient post processing of the images acquired. Complete evaluation of the precision of standard polarization parameters is described. We further present the standard features of the dedicated software that was developed to operate the camera. It provides live images of the Stokes vector components and the usual associated parameters. Finally some tests already conducted are presented. It includes indoor laboratory and outdoor measurements. This new camera will be a useful tool for many applications such as biomedical, remote sensing, metrology, material studies, and others.

  14. LROC Targeted Observations for the Next Generation of Scientific Exploration

    NASA Astrophysics Data System (ADS)

    Jolliff, B. L.

    2015-12-01

    Imaging of the Moon at high spatial resolution (0.5 to 2 mpp) by the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Cameras (NAC) plus topographic data derived from LROC NAC and WAC (Wide Angle Camera) and LOLA (Lunar Orbiting Laser Altimeter), coupled with recently obtained hyperspectral NIR and thermal data, permit studies of composition, mineralogy, and geologic context at essentially an outcrop scale. Such studies pave the way for future landed and sample return missions for high science priority targets. Among such targets are (1) the youngest volcanic rocks on the Moon, including mare basalts formed as recently as ~1 Ga, and irregular mare patches (IMPs) that appear to be even younger [1]; (2) volcanic rocks and complexes with compositions more silica-rich than mare basalts [2-4]; (3) differentiated impact-melt deposits [5,6], ancient volcanics, and compositional anomalies within the South Pole-Aitken basin; (4) exposures of recently discovered key crustal rock types in uplifted structures such as essentially pure anorthosite [7] and spinel-rich rocks [8]; and (5) frozen volatile-element-rich deposits in polar areas [9]. Important data sets include feature sequences of paired NAC images obtained under similar illumination conditions, NAC geometric stereo, from which high-resolution DTMs can be made, and photometric sequences useful for assessing composition in areas of mature cover soils. Examples of each of these target types will be discussed in context of potential future missions. References: [1] Braden et al. (2014) Nat. Geo. 7, 787-791. [2] Glotch et al. (2010) Science, 329, 1510-1513. [3] Greenhagen et al. (2010) Science, 329, 1507-1509. [4] Jolliff et al. (2011) Nat. Geo. 4, 566-571. [5] Vaughan et al (2013) PSS 91, 101-106. [6] Hurwitz and Kring (2014) J. Geophys. Res. 119, 1110-1133 [7] Ohtake et al. (2009) Nature, 461, 236-241 [8] Pieters et al. (2014) Am. Min. 99, 1893-1910. [9] Colaprete et al. (2010) Science 330, 463-468.

  15. Morphological Analysis of Lunar Lobate Scarps Using LROC NAC and LOLA Data

    NASA Astrophysics Data System (ADS)

    Banks, M. E.; Watters, T. R.; Robinson, M. S.; Tornabene, L. L.; Tran, T.; Ojha, L.

    2011-10-01

    Lobate scarps on the Moon are relatively smallscale tectonic landforms observed in mare basalts and more commonly, highland material [1-4]. These scarps are the surface expression of thrust faults, and are the most common tectonic landform on the lunar farside [1-4]. Prior to Lunar Reconnaissance Orbiter (LRO) observations, lobate scarps were largely detected only in equatorial regions because of limited Apollo Panoramic Camera and high resolution Lunar Orbiter coverage with optimum lighting geometry [1-3]. Previous measurements of the relief of lobate scarps were made for 9 low-latitude scarps (<±20°), and range from ~6 to 80 m (mean relief of ~32 m) [1]. However, the relief of these scarps was primarily determined from shadow measurements with limited accuracy from Apollo-era photography. We present the results of a detailed characterization of the relief and morphology of a larger sampling of the population of lobate scarps. Outstanding questions include what is the range of maximum relief of the lobate scarps? Is their size and structural relief consistent with estimates of the global contractional strain? What is the range of horizontal shortening expressed by lunar scarps and how does this range compare with that found for planetary lobate scarps? Lunar Reconnaissance Orbiter Camera (LROC) images and Lunar Orbiter Laser Altimeter (LOLA) ranging enable detection and detailed morphological analysis of lobate scarps at all latitudes. To date, previously undetected scarps have been identified in LROC imagery in 75 different locations, over 20 of which occur at latitudes greater than ±60° [5-6]. LROC stereo-derived digital terrain models (DTMs) and LOLA data are used to measure the relief and characterize the morphology of 26 previously known (n = 8) and newly detected (n = 18) lobate scarps. Lunar examples are compared to lobate scarps on Mars, Mercury, and 433 Eros (Hinks Dorsum).

  16. Marius Hills: Surface Roughness from LROC and Mini-RF

    NASA Astrophysics Data System (ADS)

    Lawrence, S.; Hawke, B. R.; Bussey, B.; Stopar, J. D.; Denevi, B.; Robinson, M.; Tran, T.

    2010-12-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Team is collecting hundreds of high-resolution (0.5 m/pixel) Narrow Angle Camera (NAC) images of lunar volcanic constructs (domes, “cones”, and associated features) [1,2]. Marius Hills represents the largest concentration of volcanic features on the Moon and is a high-priority target for future exploration [3,4]. NAC images of this region provide new insights into the morphology and geology of specific features at the meter scale, including lava flow fronts, tectonic features, layers, and topography (using LROC stereo imagery) [2]. Here, we report initial results from Mini-RF and LROC collaborative studies of the Marius Hills. Mini-RF uses a hybrid polarimetric architecture to measure surface backscatter characteristics and can acquire data in one of two radar bands, S (12 cm) or X (4 cm) [5]. The spatial resolution of Mini-RF (15 m/pixel) enables correlation of features observed in NAC images to Mini-RF data. Mini-RF S-Band zoom-mode data and daughter products, such as circular polarization ratio (CPR), were directly compared to NAC images. Mini-RF S-Band radar images reveal enhanced radar backscatter associated with volcanic constructs in the Marius Hills region. Mini-RF data show that Marius Hills volcanic constructs have enhanced average CPR values (0.5-0.7) compared to the CPR values of the surrounding mare (~0.4). This result is consistent with the conclusions of [6], and implies that the lava flows comprising the domes in this region are blocky. To quantify the surface roughness [e.g., 6,7] block populations associated with specific geologic features in the Marius Hills region are being digitized from NAC images. Only blocks that can be unambiguously identified (>1 m diameter) are included in the digitization process, producing counts and size estimates of the block population. High block abundances occur mainly at the distal ends of lava flows. The average size of these blocks is 9 m, and 50% of observed

  17. Digital Elevation Models and Derived Products from Lroc Nac Stereo Observations

    NASA Astrophysics Data System (ADS)

    Burns, K. N.; Speyerer, E. J.; Robinson, M. S.; Tran, T.; Rosiek, M. R.; Archinal, B. A.; Howington-Kraus, E.; the LROC Science Team

    2012-08-01

    One of the primary objectives of the Lunar Reconnaissance Orbiter Camera (LROC) is to acquire stereo observations with the Narrow Angle Camera (NAC) to enable production of high resolution digital elevation models (DEMs). This work describes the processes and techniques used in reducing the NAC stereo observations to DEMs through a combination of USGS integrated Software for Imagers and Spectrometers (ISIS) and SOCET SET® from BAE Systems by a team at Arizona State University (ASU). LROC Science Operations Center personnel have thus far reduced 130 stereo observations to DEMs of more than 130 stereo pairs for 11 Constellation Program (CxP) sites and 53 other regions of scientific interest. The NAC DEM spatial sampling is typically 2 meters, and the vertical precision is 1-2 meters. Such high resolution provides the three-dimensional view of the lunar surface required for site selection, hazard avoidance and planning traverses that minimize resource consumption. In addition to exploration analysis, geologists can measure parameters such as elevation, slope, and volume to place constraints on composition and geologic history. The NAC DEMs are released and archived through NASA's Planetary Data System.

  18. Computational imaging for miniature cameras

    NASA Astrophysics Data System (ADS)

    Salahieh, Basel

    Miniature cameras play a key role in numerous imaging applications ranging from endoscopy and metrology inspection devices to smartphones and head-mount acquisition systems. However, due to the physical constraints, the imaging conditions, and the low quality of small optics, their imaging capabilities are limited in terms of the delivered resolution, the acquired depth of field, and the captured dynamic range. Computational imaging jointly addresses the imaging system and the reconstructing algorithms to bypass the traditional limits of optical systems and deliver better restorations for various applications. The scene is encoded into a set of efficient measurements which could then be computationally decoded to output a richer estimate of the scene as compared with the raw images captured by conventional imagers. In this dissertation, three task-based computational imaging techniques are developed to make low-quality miniature cameras capable of delivering realistic high-resolution reconstructions, providing full-focus imaging, and acquiring depth information for high dynamic range objects. For the superresolution task, a non-regularized direct superresolution algorithm is developed to achieve realistic restorations without being penalized by improper assumptions (e.g., optimizers, priors, and regularizers) made in the inverse problem. An adaptive frequency-based filtering scheme is introduced to upper bound the reconstruction errors while still producing more fine details as compared with previous methods under realistic imaging conditions. For the full-focus imaging task, a computational depth-based deconvolution technique is proposed to bring a scene captured by an ordinary fixed-focus camera to a full-focus based on a depth-variant point spread function prior. The ringing artifacts are suppressed on three levels: block tiling to eliminate boundary artifacts, adaptive reference maps to reduce ringing initiated by sharp edges, and block-wise deconvolution or

  19. Image dissector camera system study

    NASA Technical Reports Server (NTRS)

    Howell, L.

    1984-01-01

    Various aspects of a rendezvous and docking system using an image dissector detector as compared to a GaAs detector were discussed. Investigation into a gimbled scanning system is also covered and the measured video response curves from the image dissector camera are presented. Rendezvous will occur at ranges greater than 100 meters. The maximum range considered was 1000 meters. During docking, the range, range-rate, angle, and angle-rate to each reflector on the satellite must be measured. Docking range will be from 3 to 100 meters. The system consists of a CW laser diode transmitter and an image dissector receiver. The transmitter beam is amplitude modulated with three sine wave tones for ranging. The beam is coaxially combined with the receiver beam. Mechanical deflection of the transmitter beam, + or - 10 degrees in both X and Y, can be accomplished before or after it is combined with the receiver beam. The receiver will have a field-of-view (FOV) of 20 degrees and an instantaneous field-of-view (IFOV) of two milliradians (mrad) and will be electronically scanned in the image dissector. The increase in performance obtained from the GaAs photocathode is not needed to meet the present performance requirements.

  20. A magnetic source imaging camera

    NASA Astrophysics Data System (ADS)

    Dolgovskiy, V.; Fescenko, I.; Sekiguchi, N.; Colombo, S.; Lebedev, V.; Zhang, J.; Weis, A.

    2016-07-01

    We describe a magnetic source imaging camera (MSIC) allowing a direct dynamic visualization of the two-dimensional spatial distribution of the individual components Bx(x ,y ), By(x ,y ) and Bz(x ,y ) of a magnetic field. The field patterns allow—in principle—a reconstruction of the distribution of sources that produce the field B → by inverse problem analysis. We compare experimentally recorded point-spread functions, i.e., field patterns produced by point-like magnetic dipoles of different orientations with anticipated field patterns. Currently, the MSIC can resolve fields of ≈10 pT (1 s measurement time) range in a field of view up to ˜20 × 20 mm2. The device has a large range of possible applications. As an example, we demonstrate the MSIC's use for recording the spatially resolved Néel magnetorelaxation of blocked magnetic nanoparticles.

  1. 3D camera tracking from disparity images

    NASA Astrophysics Data System (ADS)

    Kim, Kiyoung; Woo, Woontack

    2005-07-01

    In this paper, we propose a robust camera tracking method that uses disparity images computed from known parameters of 3D camera and multiple epipolar constraints. We assume that baselines between lenses in 3D camera and intrinsic parameters are known. The proposed method reduces camera motion uncertainty encountered during camera tracking. Specifically, we first obtain corresponding feature points between initial lenses using normalized correlation method. In conjunction with matching features, we get disparity images. When the camera moves, the corresponding feature points, obtained from each lens of 3D camera, are robustly tracked via Kanade-Lukas-Tomasi (KLT) tracking algorithm. Secondly, relative pose parameters of each lens are calculated via Essential matrices. Essential matrices are computed from Fundamental matrix calculated using normalized 8-point algorithm with RANSAC scheme. Then, we determine scale factor of translation matrix by d-motion. This is required because the camera motion obtained from Essential matrix is up to scale. Finally, we optimize camera motion using multiple epipolar constraints between lenses and d-motion constraints computed from disparity images. The proposed method can be widely adopted in Augmented Reality (AR) applications, 3D reconstruction using 3D camera, and fine surveillance systems which not only need depth information, but also camera motion parameters in real-time.

  2. AIM: Ames Imaging Module Spacecraft Camera

    NASA Technical Reports Server (NTRS)

    Thompson, Sarah

    2015-01-01

    The AIM camera is a small, lightweight, low power, low cost imaging system developed at NASA Ames. Though it has imaging capabilities similar to those of $1M plus spacecraft cameras, it does so on a fraction of the mass, power and cost budget.

  3. Uncertainty Analysis of LROC NAC Derived Elevation Models

    NASA Astrophysics Data System (ADS)

    Burns, K.; Yates, D. G.; Speyerer, E.; Robinson, M. S.

    2012-12-01

    One of the primary objectives of the Lunar Reconnaissance Orbiter Camera (LROC) [1] is to gather stereo observations with the Narrow Angle Camera (NAC) to generate digital elevation models (DEMs). From an altitude of 50 km, the NAC acquires images with a pixel scale of 0.5 meters, and a dual NAC observation covers approximately 5 km cross-track by 25 km down-track. This low altitude was common from September 2009 to December 2011. Images acquired during the commissioning phase and those acquired from the fixed orbit (after 11 December 2011) have pixel scales that range from 0.35 meters at the south pole to 2 meters at the north pole. Alimetric observations obtained by the Lunar Orbiter Laser Altimeter (LOLA) provide measurements of ±0.1 m between the spacecraft and the surface [2]. However, uncertainties in the spacecraft positioning can result in offsets (±20m) between altimeter tracks over many orbits. The LROC team is currently developing a tool to automatically register alimetric observations to NAC DEMs [3]. Using a generalized pattern search (GPS) algorithm, the new automatic registration adjusts the spacecraft position and pointing information during times when NAC images, as well as LOLA measurements, of the same region are acquired to provide an absolute reference frame for the DEM. This information is then imported into SOCET SET to aide in creating controlled NAC DEMs. For every DEM, a figure of merit (FOM) map is generated using SOCET SET software. This is a valuable tool for determining the relative accuracy of a specific pixel in a DEM. Each pixel in a FOM map is given a value to determine its "quality" by determining if the specific pixel was shadowed, saturated, suspicious, interpolated/extrapolated, or successfully correlated. The overall quality of a NAC DEM is a function of both the absolute and relative accuracies. LOLA altimetry provides the most accurate absolute geodetic reference frame with which the NAC DEMs can be compared. Offsets

  4. Coherent infrared imaging camera (CIRIC)

    SciTech Connect

    Hutchinson, D.P.; Simpson, M.L.; Bennett, C.A.; Richards, R.K.; Emery, M.S.; Crutcher, R.I.; Sitter, D.N. Jr.; Wachter, E.A.; Huston, M.A.

    1995-07-01

    New developments in 2-D, wide-bandwidth HgCdTe (MCT) and GaAs quantum-well infrared photodetectors (QWIP) coupled with Monolithic Microwave Integrated Circuit (MMIC) technology are now making focal plane array coherent infrared (IR) cameras viable. Unlike conventional IR cameras which provide only thermal data about a scene or target, a coherent camera based on optical heterodyne interferometry will also provide spectral and range information. Each pixel of the camera, consisting of a single photo-sensitive heterodyne mixer followed by an intermediate frequency amplifier and illuminated by a separate local oscillator beam, constitutes a complete optical heterodyne receiver. Applications of coherent IR cameras are numerous and include target surveillance, range detection, chemical plume evolution, monitoring stack plume emissions, and wind shear detection.

  5. Matching image color from different cameras

    NASA Astrophysics Data System (ADS)

    Fairchild, Mark D.; Wyble, David R.; Johnson, Garrett M.

    2008-01-01

    Can images from professional digital SLR cameras be made equivalent in color using simple colorimetric characterization? Two cameras were characterized, these characterizations were implemented on a variety of images, and the results were evaluated both colorimetrically and psychophysically. A Nikon D2x and a Canon 5D were used. The colorimetric analyses indicated that accurate reproductions were obtained. The median CIELAB color differences between the measured ColorChecker SG and the reproduced image were 4.0 and 6.1 for the Canon (chart and spectral respectively) and 5.9 and 6.9 for the Nikon. The median differences between cameras were 2.8 and 3.4 for the chart and spectral characterizations, near the expected threshold for reliable image difference perception. Eight scenes were evaluated psychophysically in three forced-choice experiments in which a reference image from one of the cameras was shown to observers in comparison with a pair of images, one from each camera. The three experiments were (1) a comparison of the two cameras with the chart-based characterizations, (2) a comparison with the spectral characterizations, and (3) a comparison of chart vs. spectral characterization within and across cameras. The results for the three experiments are 64%, 64%, and 55% correct respectively. Careful and simple colorimetric characterization of digital SLR cameras can result in visually equivalent color reproduction.

  6. On an assessment of surface roughness estimates from lunar laser altimetry pulse-widths for the Moon from LOLA using LROC narrow-angle stereo DTMs.

    NASA Astrophysics Data System (ADS)

    Muller, Jan-Peter; Poole, William

    2013-04-01

    Neumann et al. [1] proposed that laser altimetry pulse-widths could be employed to derive "within-footprint" surface roughness as opposed to surface roughness estimated from between laser altimetry pierce-points such as the example for Mars [2] and more recently from the 4-pointed star-shaped LOLA (Lunar reconnaissance Orbiter Laser Altimeter) onboard the NASA-LRO [3]. Since 2009, the LOLA has been collecting extensive global laser altimetry data with a 5m footprint and ?25m between the 5 points in a star-shape. In order to assess how accurately surface roughness (defined as simple RMS after slope correction) derived from LROC matches with surface roughness derived from LOLA footprints, publicly released LROC-NA (LRO Camera Narrow Angle) 1m Digital Terrain Models (DTMs) were employed to measure the surface roughness directly within each 5m footprint. A set of 20 LROC-NA DTMs were examined. Initially the match-up between the LOLA and LROC-NA orthorectified images (ORIs) is assessed visually to ensure that the co-registration is better than the LOLA footprint resolution. For each LOLA footprint, the pulse-width geolocation is then retrieved and this is used to "cookie-cut" the surface roughness and slopes derived from the LROC-NA DTMs. The investigation which includes data from a variety of different landforms shows little, if any correlation between surface roughness estimated from DTMs with LOLA pulse-widths at sub-footprint scale. In fact there is only any perceptible correlation between LOLA and LROC-DTMs at baselines of 40-60m for surface roughness and 20m for slopes. [1] Neumann et al. Mars Orbiter Laser Altimeter pulse width measurements and footprint-scale roughness. Geophysical Research Letters (2003) vol. 30 (11), paper 1561. DOI: 10.1029/2003GL017048 [2] Kreslavsky and Head. Kilometer-scale roughness of Mars: results from MOLA data analysis. J Geophys Res (2000) vol. 105 (E11) pp. 26695-26711. [3] Rosenburg et al. Global surface slopes and roughness of the

  7. LRO Camera Imaging of Potential Landing Sites in the South Pole-Aitken Basin

    NASA Astrophysics Data System (ADS)

    Jolliff, B. L.; Wiseman, S. M.; Gibson, K. E.; Lauber, C.; Robinson, M.; Gaddis, L. R.; Scholten, F.; Oberst, J.; LROC Science; Operations Team

    2010-12-01

    We show results of WAC (Wide Angle Camera) and NAC (Narrow Angle Camera) imaging of candidate landing sites within the South Pole-Aitken (SPA) basin of the Moon obtained by the Lunar Reconnaissance Orbiter during the first full year of operation. These images enable a greatly improved delineation of geologic units, determination of unit thicknesses and stratigraphy, and detailed surface characterization that has not been possible with previous data. WAC imaging encompasses the entire SPA basin, located within an area ranging from ~ 130-250 degrees east longitude and ~15 degrees south latitude to the South Pole, at different incidence angles, with the specific range of incidence dependent on latitude. The WAC images show morphology and surface detail at better than 100 m per pixel, with spatial coverage and quality unmatched by previous data sets. NAC images reveal details at the sub-meter pixel scale that enable new ways to evaluate the origins and stratigraphy of deposits. Key among new results is the capability to discern extents of ancient volcanic deposits that are covered by later crater ejecta (cryptomare) [see Petro et al., this conference] using new, complementary color data from Kaguya and Chandrayaan-1. Digital topographic models derived from WAC and NAC geometric stereo coverage show broad intercrater-plains areas where slopes are acceptably low for high-probability safe landing [see Archinal et al., this conference]. NAC images allow mapping and measurement of small, fresh craters that excavated boulders and thus provide information on surface roughness and depth to bedrock beneath regolith and plains deposits. We use these data to estimate deposit thickness in areas of interest for landing and potential sample collection to better understand the possible provenance of samples. Also, small regions marked by fresh impact craters and their associated boulder fields are readily identified by their bright ejecta patterns and marked as lander keep-out zones

  8. Camera lens adapter magnifies image

    NASA Technical Reports Server (NTRS)

    Moffitt, F. L.

    1967-01-01

    Polaroid Land camera with an illuminated 7-power magnifier adapted to the lens, photographs weld flaws. The flaws are located by inspection with a 10-power magnifying glass and then photographed with this device, thus providing immediate pictorial data for use in remedial procedures.

  9. Generating Stereoscopic Television Images With One Camera

    NASA Technical Reports Server (NTRS)

    Coan, Paul P.

    1996-01-01

    Straightforward technique for generating stereoscopic television images involves use of single television camera translated laterally between left- and right-eye positions. Camera acquires one of images (left- or right-eye image), and video signal from image delayed while camera translated to position where it acquires other image. Length of delay chosen so both images displayed simultaneously or as nearly simultaneously as necessary to obtain stereoscopic effect. Technique amenable to zooming in on small areas within broad scenes. Potential applications include three-dimensional viewing of geological features and meteorological events from spacecraft and aircraft, inspection of workpieces moving along conveyor belts, and aiding ground and water search-and-rescue operations. Also used to generate and display imagery for public education and general information, and possible for medical purposes.

  10. Classroom multispectral imaging using inexpensive digital cameras.

    NASA Astrophysics Data System (ADS)

    Fortes, A. D.

    2007-12-01

    The proliferation of increasingly cheap digital cameras in recent years means that it has become easier to exploit the broad wavelength sensitivity of their CCDs (360 - 1100 nm) for classroom-based teaching. With the right tools, it is possible to open children's eyes to the invisible world of UVA and near-IR radiation either side of our narrow visual band. The camera-filter combinations I describe can be used to explore the world of animal vision, looking for invisible markings on flowers, or in bird plumage, for example. In combination with a basic spectroscope (such as the Project-STAR handheld plastic spectrometer, 25), it is possible to investigate the range of human vision and camera sensitivity, and to explore the atomic and molecular absorption lines from the solar and terrestrial atmospheres. My principal use of the cameras has been to teach multispectral imaging of the kind used to determine remotely the composition of planetary surfaces. A range of camera options, from 50 circuit-board mounted CCDs up to $900 semi-pro infrared camera kits (including mobile phones along the way), and various UV-vis-IR filter options will be presented. Examples of multispectral images taken with these systems are used to illustrate the range of classroom topics that can be covered. Particular attention is given to learning about spectral reflectance curves and comparing images from Earth and Mars taken using the same filter combination that it used on the Mars Rovers.

  11. Multiple-image oscilloscope camera

    DOEpatents

    Yasillo, Nicholas J.

    1978-01-01

    An optical device for placing automatically a plurality of images at selected locations on one film comprises a stepping motor coupled to a rotating mirror and lens. A mechanical connection from the mirror controls an electronic logical system to allow rotation of the mirror to place a focused image at the desired preselected location. The device is of especial utility when used to place four images on a single film to record oscilloscope views obtained in gamma radiography.

  12. Prediction of Viking lander camera image quality

    NASA Technical Reports Server (NTRS)

    Huck, F. O.; Burcher, E. E.; Jobson, D. J.; Wall, S. D.

    1976-01-01

    Formulations are presented that permit prediction of image quality as a function of camera performance, surface radiance properties, and lighting and viewing geometry. Predictions made for a wide range of surface radiance properties reveal that image quality depends strongly on proper camera dynamic range command and on favorable lighting and viewing geometry. Proper camera dynamic range commands depend mostly on the surface albedo that will be encountered. Favorable lighting and viewing geometries depend mostly on lander orientation with respect to the diurnal sun path over the landing site, and tend to be independent of surface albedo and illumination scattering function. Side lighting with low sun elevation angles (10 to 30 deg) is generally favorable for imaging spatial details and slopes, whereas high sun elevation angles are favorable for measuring spectral reflectances.

  13. Improvement of passive THz camera images

    NASA Astrophysics Data System (ADS)

    Kowalski, Marcin; Piszczek, Marek; Palka, Norbert; Szustakowski, Mieczyslaw

    2012-10-01

    Terahertz technology is one of emerging technologies that has a potential to change our life. There are a lot of attractive applications in fields like security, astronomy, biology and medicine. Until recent years, terahertz (THz) waves were an undiscovered, or most importantly, an unexploited area of electromagnetic spectrum. The reasons of this fact were difficulties in generation and detection of THz waves. Recent advances in hardware technology have started to open up the field to new applications such as THz imaging. The THz waves can penetrate through various materials. However, automated processing of THz images can be challenging. The THz frequency band is specially suited for clothes penetration because this radiation does not point any harmful ionizing effects thus it is safe for human beings. Strong technology development in this band have sparked with few interesting devices. Even if the development of THz cameras is an emerging topic, commercially available passive cameras still offer images of poor quality mainly because of its low resolution and low detectors sensitivity. Therefore, THz image processing is very challenging and urgent topic. Digital THz image processing is a really promising and cost-effective way for demanding security and defense applications. In the article we demonstrate the results of image quality enhancement and image fusion of images captured by a commercially available passive THz camera by means of various combined methods. Our research is focused on dangerous objects detection - guns, knives and bombs hidden under some popular types of clothing.

  14. Camera Trajectory fromWide Baseline Images

    NASA Astrophysics Data System (ADS)

    Havlena, M.; Torii, A.; Pajdla, T.

    2008-09-01

    Camera trajectory estimation, which is closely related to the structure from motion computation, is one of the fundamental tasks in computer vision. Reliable camera trajectory estimation plays an important role in 3D reconstruction, self localization, and object recognition. There are essential issues for a reliable camera trajectory estimation, for instance, choice of the camera and its geometric projection model, camera calibration, image feature detection and description, and robust 3D structure computation. Most of approaches rely on classical perspective cameras because of the simplicity of their projection models and ease of their calibration. However, classical perspective cameras offer only a limited field of view, and thus occlusions and sharp camera turns may cause that consecutive frames look completely different when the baseline becomes longer. This makes the image feature matching very difficult (or impossible) and the camera trajectory estimation fails under such conditions. These problems can be avoided if omnidirectional cameras, e.g. a fish-eye lens convertor, are used. The hardware which we are using in practice is a combination of Nikon FC-E9 mounted via a mechanical adaptor onto a Kyocera Finecam M410R digital camera. Nikon FC-E9 is a megapixel omnidirectional addon convertor with 180° view angle which provides images of photographic quality. Kyocera Finecam M410R delivers 2272×1704 images at 3 frames per second. The resulting combination yields a circular view of diameter 1600 pixels in the image. Since consecutive frames of the omnidirectional camera often share a common region in 3D space, the image feature matching is often feasible. On the other hand, the calibration of these cameras is non-trivial and is crucial for the accuracy of the resulting 3D reconstruction. We calibrate omnidirectional cameras off-line using the state-of-the-art technique and Mičušík's two-parameter model, that links the radius of the image point r to the

  15. Imaging characteristics of photogrammetric camera systems

    USGS Publications Warehouse

    Welch, R.; Halliday, J.

    1973-01-01

    In view of the current interest in high-altitude and space photographic systems for photogrammetric mapping, the United States Geological Survey (U.S.G.S.) undertook a comprehensive research project designed to explore the practical aspects of applying the latest image quality evaluation techniques to the analysis of such systems. The project had two direct objectives: (1) to evaluate the imaging characteristics of current U.S.G.S. photogrammetric camera systems; and (2) to develop methodologies for predicting the imaging capabilities of photogrammetric camera systems, comparing conventional systems with new or different types of systems, and analyzing the image quality of photographs. Image quality was judged in terms of a number of evaluation factors including response functions, resolving power, and the detectability and measurability of small detail. The limiting capabilities of the U.S.G.S. 6-inch and 12-inch focal length camera systems were established by analyzing laboratory and aerial photographs in terms of these evaluation factors. In the process, the contributing effects of relevant parameters such as lens aberrations, lens aperture, shutter function, image motion, film type, and target contrast procedures for analyzing image quality and predicting and comparing performance capabilities. ?? 1973.

  16. COMPUTER ANALYSIS OF PLANAR GAMMA CAMERA IMAGES

    EPA Science Inventory



    COMPUTER ANALYSIS OF PLANAR GAMMA CAMERA IMAGES

    T Martonen1 and J Schroeter2

    1Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. EPA, Research Triangle Park, NC 27711 USA and 2Curriculum in Toxicology, Unive...

  17. Pre-flight and On-orbit Geometric Calibration of the Lunar Reconnaissance Orbiter Camera

    NASA Astrophysics Data System (ADS)

    Speyerer, E. J.; Wagner, R. V.; Robinson, M. S.; Licht, A.; Thomas, P. C.; Becker, K.; Anderson, J.; Brylow, S. M.; Humm, D. C.; Tschimmel, M.

    2016-04-01

    The Lunar Reconnaissance Orbiter Camera (LROC) consists of two imaging systems that provide multispectral and high resolution imaging of the lunar surface. The Wide Angle Camera (WAC) is a seven color push-frame imager with a 90∘ field of view in monochrome mode and 60∘ field of view in color mode. From the nominal 50 km polar orbit, the WAC acquires images with a nadir ground sampling distance of 75 m for each of the five visible bands and 384 m for the two ultraviolet bands. The Narrow Angle Camera (NAC) consists of two identical cameras capable of acquiring images with a ground sampling distance of 0.5 m from an altitude of 50 km. The LROC team geometrically calibrated each camera before launch at Malin Space Science Systems in San Diego, California and the resulting measurements enabled the generation of a detailed camera model for all three cameras. The cameras were mounted and subsequently launched on the Lunar Reconnaissance Orbiter (LRO) on 18 June 2009. Using a subset of the over 793000 NAC and 207000 WAC images of illuminated terrain collected between 30 June 2009 and 15 December 2013, we improved the interior and exterior orientation parameters for each camera, including the addition of a wavelength dependent radial distortion model for the multispectral WAC. These geometric refinements, along with refined ephemeris, enable seamless projections of NAC image pairs with a geodetic accuracy better than 20 meters and sub-pixel precision and accuracy when orthorectifying WAC images.

  18. Cervical SPECT Camera for Parathyroid Imaging

    SciTech Connect

    None, None

    2012-08-31

    Primary hyperparathyroidism characterized by one or more enlarged parathyroid glands has become one of the most common endocrine diseases in the world affecting about 1 per 1000 in the United States. Standard treatment is highly invasive exploratory neck surgery called Parathyroidectomy. The surgery has a notable mortality rate because of the close proximity to vital structures. The move to minimally invasive parathyroidectomy is hampered by the lack of high resolution pre-surgical imaging techniques that can accurately localize the parathyroid with respect to surrounding structures. We propose to develop a dedicated ultra-high resolution (~ 1 mm) and high sensitivity (10x conventional camera) cervical scintigraphic imaging device. It will be based on a multiple pinhole-camera SPECT system comprising a novel solid state CZT detector that offers the required performance. The overall system will be configured to fit around the neck and comfortably image a patient.

  19. Imaging spectrometer/camera having convex grating

    NASA Technical Reports Server (NTRS)

    Reininger, Francis M. (Inventor)

    2000-01-01

    An imaging spectrometer has fore-optics coupled to a spectral resolving system with an entrance slit extending in a first direction at an imaging location of the fore-optics for receiving the image, a convex diffraction grating for separating the image into a plurality of spectra of predetermined wavelength ranges; a spectrometer array for detecting the spectra; and at least one concave sperical mirror concentric with the diffraction grating for relaying the image from the entrance slit to the diffraction grating and from the diffraction grating to the spectrometer array. In one embodiment, the spectrometer is configured in a lateral mode in which the entrance slit and the spectrometer array are displaced laterally on opposite sides of the diffraction grating in a second direction substantially perpendicular to the first direction. In another embodiment, the spectrometer is combined with a polychromatic imaging camera array disposed adjacent said entrance slit for recording said image.

  20. Investigation of Layered Lunar Mare Lava flows through LROC Imagery and Terrestrial Analogs

    NASA Astrophysics Data System (ADS)

    Needham, H.; Rumpf, M.; Sarah, F.

    2013-12-01

    High resolution images of the lunar surface have revealed layered deposits in the walls of impact craters and pit craters in the lunar maria, which are interpreted to be sequences of stacked lava flows. The goal of our research is to establish quantitative constraints and uncertainties on the thicknesses of individual flow units comprising the layered outcrops, in order to model the cooling history of lunar lava flows. The underlying motivation for this project is to identify locations hosting intercalated units of lava flows and paleoregoliths, which may preserve snapshots of the ancient solar wind and other extra-lunar particles, thereby providing potential sampling localities for future missions to the lunar surface. Our approach involves mapping layered outcrops using high-resolution imagery acquired by the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC), with constraints on flow unit dimensions provided by Lunar Orbiter Laser Altimeter (LOLA) data. We have measured thicknesses of ~ 2 to > 20 m. However, there is considerable uncertainty in the definition of contacts between adjacent units, primarily because talus commonly obscures contacts and/or prevents lateral tracing of the flow units. In addition, flows may have thicknesses or geomorphological complexity at scales approaching the limit of resolution of the data, which hampers distinguishing one unit from another. To address these issues, we have undertaken a terrestrial analog study using World View 2 satellite imagery of layered lava sequences on Oahu, Hawaii. These data have a resolution comparable to LROC NAC images of 0.5 m. The layered lava sequences are first analyzed in ArcGIS to obtain an initial estimate of the number and thicknesses of flow units identified in the images. We next visit the outcrops in the field to perform detailed measurements of the individual units. We have discovered that the number of flow units identified in the remote sensing data is fewer compared to

  1. Camera settings for UAV image acquisition

    NASA Astrophysics Data System (ADS)

    O'Connor, James; Smith, Mike J.; James, Mike R.

    2016-04-01

    The acquisition of aerial imagery has become more ubiquitous than ever in the geosciences due to the advent of consumer-grade UAVs capable of carrying imaging devices. These allow the collection of high spatial resolution data in a timely manner with little expertise. Conversely, the cameras/lenses used to acquire this imagery are often given less thought, and can be unfit for purpose. Given weight constraints which are frequently an issue with UAV flights, low-payload UAVs (<1 kg) limit the types of cameras/lenses which could potentially be used for specific surveys, and therefore the quality of imagery which can be acquired. This contribution discusses these constraints, which need to be considered when selecting a camera/lens for conducting a UAV survey and how they can best be optimized. These include balancing of the camera exposure triangle (ISO, Shutter speed, Aperture) to ensure sharp, well exposed imagery, and its interactions with other camera parameters (Sensor size, Focal length, Pixel pitch) as well as UAV flight parameters (height, velocity).

  2. X-ray imaging using digital cameras

    NASA Astrophysics Data System (ADS)

    Winch, Nicola M.; Edgar, Andrew

    2012-03-01

    The possibility of using the combination of a computed radiography (storage phosphor) cassette and a semiprofessional grade digital camera for medical or dental radiography is investigated. We compare the performance of (i) a Canon 5D Mk II single lens reflex camera with f1.4 lens and full-frame CMOS array sensor and (ii) a cooled CCD-based camera with a 1/3 frame sensor and the same lens system. Both systems are tested with 240 x 180 mm cassettes which are based on either powdered europium-doped barium fluoride bromide or needle structure europium-doped cesium bromide. The modulation transfer function for both systems has been determined and falls to a value of 0.2 at around 2 lp/mm, and is limited by light scattering of the emitted light from the storage phosphor rather than the optics or sensor pixelation. The modulation transfer function for the CsBr:Eu2+ plate is bimodal, with a high frequency wing which is attributed to the light-guiding behaviour of the needle structure. The detective quantum efficiency has been determined using a radioisotope source and is comparatively low at 0.017 for the CMOS camera and 0.006 for the CCD camera, attributed to the poor light harvesting by the lens. The primary advantages of the method are portability, robustness, digital imaging and low cost; the limitations are the low detective quantum efficiency and hence signal-to-noise ratio for medical doses, and restricted range of plate sizes. Representative images taken with medical doses are shown and illustrate the potential use for portable basic radiography.

  3. Imaging of gamma emitters using scintillation cameras

    NASA Astrophysics Data System (ADS)

    Ricard, Marcel

    2004-07-01

    Since their introduction by Hal Anger in the late 1950s, the gamma cameras have been widely used in the field of nuclear medicine. The original concept is based on the association of a large field of view scintillator optically coupled with an array of photomultiplier tubes (PMTs), in order to locate the position of interactions inside the crystal. Using a dedicated accessory, like a parallel hole collimator, to focus the field of view toward a predefined direction, it is possible to built up an image of the radioactive distribution. In terms of imaging performances, three main characteristics are commonly considered: uniformity, spatial resolution and energy resolution. Major improvements were mainly due to progress in terms of industrial process regarding analogical electronic, crystal growing or PMTs manufacturing. Today's gamma camera is highly digital, from the PMTs to the display. All the corrections are applied "on the fly" using up to date signal processing techniques. At the same time some significant progresses have been achieved in the field of collimators. Finally, two new technologies have been implemented, solid detectors like CdTe or CdZnTe, and pixellized scintillators plus photodiodes or position sensitive photomultiplier tubes. These solutions are particularly well adapted to build dedicated gamma camera for breast or intraoperative imaging.

  4. 15 CFR 743.3 - Thermal imaging camera reporting.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Thermal imaging camera reporting. 743... REPORTING AND NOTIFICATION § 743.3 Thermal imaging camera reporting. (a) General requirement. Exports of thermal imaging cameras must be reported to BIS as provided in this section. (b) Transactions to...

  5. 15 CFR 743.3 - Thermal imaging camera reporting.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Thermal imaging camera reporting. 743... REPORTING § 743.3 Thermal imaging camera reporting. (a) General requirement. Exports of thermal imaging cameras must be reported to BIS as provided in this section. (b) Transactions to be reported. Exports...

  6. 15 CFR 743.3 - Thermal imaging camera reporting.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Thermal imaging camera reporting. 743... REPORTING § 743.3 Thermal imaging camera reporting. (a) General requirement. Exports of thermal imaging cameras must be reported to BIS as provided in this section. (b) Transactions to be reported. Exports...

  7. 15 CFR 743.3 - Thermal imaging camera reporting.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Thermal imaging camera reporting. 743... REPORTING § 743.3 Thermal imaging camera reporting. (a) General requirement. Exports of thermal imaging cameras must be reported to BIS as provided in this section. (b) Transactions to be reported. Exports...

  8. 15 CFR 743.3 - Thermal imaging camera reporting.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Thermal imaging camera reporting. 743... REPORTING § 743.3 Thermal imaging camera reporting. (a) General requirement. Exports of thermal imaging cameras must be reported to BIS as provided in this section. (b) Transactions to be reported. Exports...

  9. Enhancement of document images from cameras

    NASA Astrophysics Data System (ADS)

    Taylor, Michael J.; Dance, Christopher R.

    1998-04-01

    As digital cameras become cheaper and more powerful, driven by the consumer digital photography market, we anticipate significant value in extending their utility as a general office peripheral by adding a paper scanning capability. The main technical challenges in realizing this new scanning interface are insufficient resolution, blur and lighting variations. We have developed an efficient technique for the recovery of text from digital camera images, which simultaneously treats these three problems, unlike other local thresholding algorithms which do not cope with blur and resolution enhancement. The technique first performs deblurring by deconvolution, and then resolution enhancement by linear interpolation. We compare the performance of a threshold derived from the local mean and variance of all pixel values within a neighborhood with a threshold derived from the local mean of just those pixels with high gradient. We assess performance using OCR error scores.

  10. The Widespread Distribution of Swirls in Lunar Reconnaissance Orbiter Camera Images

    NASA Astrophysics Data System (ADS)

    Denevi, B. W.; Robinson, M. S.; Boyd, A. K.; Blewett, D. T.

    2015-10-01

    Lunar swirls, the sinuous high-and low-reflectance features that cannot be mentioned without the associated adjective "enigmatic,"are of interest because of their link to crustal magnetic anomalies [1,2]. These localized magnetic anomalies create mini-magnetospheres [3,4] and may alter the typical surface modification processes or result in altogether distinct processes that form the swirls. One hypothesis is that magnetic anomalies may provide some degree of shielding from the solar wind [1,2], which could impede space weathering due to solar wind sputtering. In this case, swirls would serve as a way to compare areas affected by typical lunar space weathering (solar wind plus micrometeoroid bombardment) to those where space weathering is dominated by micrometeoroid bombardment alone, providing a natural means to assess the relative contributions of these two processes to the alteration of fresh regolith. Alternately,magnetic anomalies may play a role in the sorting of soil grains, such that the high-reflectance portion of swirls may preferentially accumulate feldspar-rich dust [5]or soils with a lower component of nanophase iron [6].Each of these scenarios presumes a pre-existing magnetic anomaly; swirlshave also been suggested to be the result of recent cometary impacts in which the remanent magnetic field is generated by the impact event[7].Here we map the distribution of swirls using ultraviolet and visible images from the Lunar Reconnaissance Orbiter Camera(LROC) Wide Angle Camera (WAC) [8,9]. We explore the relationship of the swirls to crustal magnetic anomalies[10], and examine regions with magnetic anomalies and no swirls.

  11. Calibrating Images from the MINERVA Cameras

    NASA Astrophysics Data System (ADS)

    Mercedes Colón, Ana

    2016-01-01

    The MINiature Exoplanet Radial Velocity Array (MINERVA) consists of an array of robotic telescopes located on Mount Hopkins, Arizona with the purpose of performing transit photometry and spectroscopy to find Earth-like planets around Sun-like stars. In order to make photometric observations, it is necessary to perform calibrations on the CCD cameras of the telescopes to take into account possible instrument error on the data. In this project, we developed a pipeline that takes optical images, calibrates them using sky flats, darks, and biases to generate a transit light curve.

  12. Methods for identification of images acquired with digital cameras

    NASA Astrophysics Data System (ADS)

    Geradts, Zeno J.; Bijhold, Jurrien; Kieft, Martijn; Kurosawa, Kenji; Kuroki, Kenro; Saitoh, Naoki

    2001-02-01

    From the court we were asked whether it is possible to determine if an image has been made with a specific digital camera. This question has to be answered in child pornography cases, where evidence is needed that a certain picture has been made with a specific camera. We have looked into different methods of examining the cameras to determine if a specific image has been made with a camera: defects in CCDs, file formats that are used, noise introduced by the pixel arrays and watermarking in images used by the camera manufacturer.

  13. Speckle Camera Imaging of the Planet Pluto

    NASA Astrophysics Data System (ADS)

    Howell, Steve B.; Horch, Elliott P.; Everett, Mark E.; Ciardi, David R.

    2012-10-01

    We have obtained optical wavelength (692 nm and 880 nm) speckle imaging of the planet Pluto and its largest moon Charon. Using our DSSI speckle camera attached to the Gemini North 8 m telescope, we collected high resolution imaging with an angular resolution of ~20 mas, a value at the Gemini-N telescope diffraction limit. We have produced for this binary system the first speckle reconstructed images, from which we can measure not only the orbital separation and position angle for Charon, but also the diameters of the two bodies. Our measurements of these parameters agree, within the uncertainties, with the current best values for Pluto and Charon. The Gemini-N speckle observations of Pluto are presented to illustrate the capabilities of our instrument and the robust production of high accuracy, high spatial resolution reconstructed images. We hope our results will suggest additional applications of high resolution speckle imaging for other objects within our solar system and beyond. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).

  14. Camera system for multispectral imaging of documents

    NASA Astrophysics Data System (ADS)

    Christens-Barry, William A.; Boydston, Kenneth; France, Fenella G.; Knox, Keith T.; Easton, Roger L., Jr.; Toth, Michael B.

    2009-02-01

    A spectral imaging system comprising a 39-Mpixel monochrome camera, LED-based narrowband illumination, and acquisition/control software has been designed for investigations of cultural heritage objects. Notable attributes of this system, referred to as EurekaVision, include: streamlined workflow, flexibility, provision of well-structured data and metadata for downstream processing, and illumination that is safer for the artifacts. The system design builds upon experience gained while imaging the Archimedes Palimpsest and has been used in studies of a number of important objects in the LOC collection. This paper describes practical issues that were considered by EurekaVision to address key research questions for the study of fragile and unique cultural objects over a range of spectral bands. The system is intended to capture important digital records for access by researchers, professionals, and the public. The system was first used for spectral imaging of the 1507 world map by Martin Waldseemueller, the first printed map to reference "America." It was also used to image sections of the Carta Marina 1516 map by the same cartographer for comparative purposes. An updated version of the system is now being utilized by the Preservation Research and Testing Division of the Library of Congress.

  15. Tectonic Mapping of Mare Frigoris Using Lunar Reconnaissance Orbiter Camera Images

    NASA Astrophysics Data System (ADS)

    Williams, N. R.; Bell, J. F.; Watters, T. R.; Banks, M. E.; Robinson, M. S.

    2012-12-01

    Conventional wisdom has been that extensional tectonism on the Moon largely ended ~3.6 billion years ago and that contractional deformation ended ~1.2 billion years ago. New NASA Lunar Reconnaissance Orbiter Camera (LROC) high resolution images are forcing a re-assessment of this view. Mapping in Mare Frigoris and the surrounding area has revealed many tectonic landforms enabling new investigations of the region's structural evolution. Sinuous wrinkle ridges with hundreds of meters of relief are interpreted as folded basalt layers overlying thrust faults. They have often been associated with lunar mascons identified by positive free-air gravity anomalies where thick basaltic lava causes flexure and subsidence to form ridges. No mascon-like gravity anomaly is associated with Mare Frigoris, yet large ridges deform the mare basalts. Lobate scarps are also found near Frigoris. These asymmetric linear hills inferred to be surface expressions of thrust faults are distributed globally and thought to originate from cooling and radial contraction of the lunar interior. Clusters of meter-scale extensional troughs or graben bounded by normal faults also occur in Frigoris. Tectonic landforms are being mapped in and around Mare Frigoris using LROC Narrow Angle Camera (NAC) images. Preliminary results show that wrinkle ridges in Frigoris occur both near and distal to the basin perimeter, trend E/W in western and central Frigoris, and form a polygonal pattern in the eastern section. Several complex wrinkle ridges are observed to transition into morphologically simpler lobate scarps at mare/highland boundaries, with the contrast in tectonic morphology likely due to the change from layered (mare) to un-layered (highlands) substrate. Lobate scarps in Frigoris occur primarily in the highlands, tend to strike E/W, and often but not always follow the boundary between mare and highlands. Small graben mapped in Frigoris occur in several clusters adjacent to or atop ridges and scarps, and

  16. Fast Camera Imaging of Hall Thruster Ignition

    SciTech Connect

    C.L. Ellison, Y. Raitses and N.J. Fisch

    2011-02-24

    Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 μs. The cathode introduces azimuthal asymmetry, which persists for about 30 μs into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruster

  17. Image responses to x-ray radiation in ICCD camera

    NASA Astrophysics Data System (ADS)

    Ma, Jiming; Duan, Baojun; Song, Yan; Song, Guzhou; Han, Changcai; Zhou, Ming; Du, Jiye; Wang, Qunshu; Zhang, Jianqi

    2013-08-01

    When used in digital radiography, ICCD camera will be inevitably irradiated by x-ray and the output image will degrade. In this research, we separated ICCD camera into two optical-electric parts, CCD camera and MCP image intensifier, and irradiated them respectively on Co-60 gamma ray source and pulsed x-ray source. By changing time association between radiation and the shutter of CCD camera, the state of power supply of MCP image intensifier, significant differences have been observed in output images. A further analysis has revealed the influence of the CCD chip, readout circuit in CCD camera, and the photocathode, microchannel plate and fluorescent screen in MCP image intensifier on image quality of an irradiated ICCD camera. The study demonstrated that compared with other parts, irradiation response of readout circuit is very slight and in most cases negligible. The interaction of x-ray with CCD chip usually behaves as bright spots or rough background in output images, which depends on x-ray doses. As to the MCP image intensifier, photocathode and microchannel plate are the two main steps that degrade output images. When being irradiated by x-ray, microchannel plate in MCP image intensifier tends to contribute a bright background in output images. Background caused by the photocathode looks more bright and fluctuant. Image responses of fluorescent screen in MCP image intensifier in ICCD camera and that of a coupling fiber bundle are also evaluated in this presentation.

  18. New insight into lunar impact melt mobility from the LRO camera

    USGS Publications Warehouse

    Bray, Veronica J.; Tornabene, Livio L.; Keszthelyi, Laszlo P.; McEwen, Alfred S.; Hawke, B. Ray; Giguere, Thomas A.; Kattenhorn, Simon A.; Garry, William B.; Rizk, Bashar; Caudill, C.M.; Gaddis, Lisa R.; van der Bogert, Carolyn H.

    2010-01-01

    The Lunar Reconnaissance Orbiter Camera (LROC) is systematically imaging impact melt deposits in and around lunar craters at meter and sub-meter scales. These images reveal that lunar impact melts, although morphologically similar to terrestrial lava flows of similar size, exhibit distinctive features (e.g., erosional channels). Although generated in a single rapid event, the post-impact mobility and morphology of lunar impact melts is surprisingly complex. We present evidence for multi-stage influx of impact melt into flow lobes and crater floor ponds. Our volume and cooling time estimates for the post-emplacement melt movements noted in LROC images suggest that new flows can emerge from melt ponds an extended time period after the impact event.

  19. Spectral Camera based on Ghost Imaging via Sparsity Constraints

    PubMed Central

    Liu, Zhentao; Tan, Shiyu; Wu, Jianrong; Li, Enrong; Shen, Xia; Han, Shensheng

    2016-01-01

    The image information acquisition ability of a conventional camera is usually much lower than the Shannon Limit since it does not make use of the correlation between pixels of image data. Applying a random phase modulator to code the spectral images and combining with compressive sensing (CS) theory, a spectral camera based on true thermal light ghost imaging via sparsity constraints (GISC spectral camera) is proposed and demonstrated experimentally. GISC spectral camera can acquire the information at a rate significantly below the Nyquist rate, and the resolution of the cells in the three-dimensional (3D) spectral images data-cube can be achieved with a two-dimensional (2D) detector in a single exposure. For the first time, GISC spectral camera opens the way of approaching the Shannon Limit determined by Information Theory in optical imaging instruments. PMID:27180619

  20. Spectral Camera based on Ghost Imaging via Sparsity Constraints

    NASA Astrophysics Data System (ADS)

    Liu, Zhentao; Tan, Shiyu; Wu, Jianrong; Li, Enrong; Shen, Xia; Han, Shensheng

    2016-05-01

    The image information acquisition ability of a conventional camera is usually much lower than the Shannon Limit since it does not make use of the correlation between pixels of image data. Applying a random phase modulator to code the spectral images and combining with compressive sensing (CS) theory, a spectral camera based on true thermal light ghost imaging via sparsity constraints (GISC spectral camera) is proposed and demonstrated experimentally. GISC spectral camera can acquire the information at a rate significantly below the Nyquist rate, and the resolution of the cells in the three-dimensional (3D) spectral images data-cube can be achieved with a two-dimensional (2D) detector in a single exposure. For the first time, GISC spectral camera opens the way of approaching the Shannon Limit determined by Information Theory in optical imaging instruments.

  1. Spectral Camera based on Ghost Imaging via Sparsity Constraints.

    PubMed

    Liu, Zhentao; Tan, Shiyu; Wu, Jianrong; Li, Enrong; Shen, Xia; Han, Shensheng

    2016-01-01

    The image information acquisition ability of a conventional camera is usually much lower than the Shannon Limit since it does not make use of the correlation between pixels of image data. Applying a random phase modulator to code the spectral images and combining with compressive sensing (CS) theory, a spectral camera based on true thermal light ghost imaging via sparsity constraints (GISC spectral camera) is proposed and demonstrated experimentally. GISC spectral camera can acquire the information at a rate significantly below the Nyquist rate, and the resolution of the cells in the three-dimensional (3D) spectral images data-cube can be achieved with a two-dimensional (2D) detector in a single exposure. For the first time, GISC spectral camera opens the way of approaching the Shannon Limit determined by Information Theory in optical imaging instruments. PMID:27180619

  2. Analysis of Melt Flows observed by SIR-2 and LROC NAC: Stevinus A

    NASA Astrophysics Data System (ADS)

    Mall, U.; Wöhler, C.; Grumpe, A.; Bugiolacchi, R.

    2013-09-01

    Impact melt structures occur in and around young craters from 200 m to hundreds of kilometers in diameter. Impact events lead to melting and vaporization processes. Through the combination of high-resolution LROC NAC images and measurements made by the SIR-2 point spectrometer carried by Chandrayaan-1, compositional aspects can be investigated in a manner hitherto impossible. We will present and discuss as a specific example first results for the small lunar crater Stevinus A.

  3. Plenoptic camera image simulation for reconstruction algorithm verification

    NASA Astrophysics Data System (ADS)

    Schwiegerling, Jim

    2014-09-01

    Plenoptic cameras have emerged in recent years as a technology for capturing light field data in a single snapshot. A conventional digital camera can be modified with the addition of a lenslet array to create a plenoptic camera. Two distinct camera forms have been proposed in the literature. The first has the camera image focused onto the lenslet array. The lenslet array is placed over the camera sensor such that each lenslet forms an image of the exit pupil onto the sensor. The second plenoptic form has the lenslet array relaying the image formed by the camera lens to the sensor. We have developed a raytracing package that can simulate images formed by a generalized version of the plenoptic camera. Several rays from each sensor pixel are traced backwards through the system to define a cone of rays emanating from the entrance pupil of the camera lens. Objects that lie within this cone are integrated to lead to a color and exposure level for that pixel. To speed processing three-dimensional objects are approximated as a series of planes at different depths. Repeating this process for each pixel in the sensor leads to a simulated plenoptic image on which different reconstruction algorithms can be tested.

  4. Geometric rectification of camera-captured document images.

    PubMed

    Liang, Jian; DeMenthon, Daniel; Doermann, David

    2008-04-01

    Compared to typical scanners, handheld cameras offer convenient, flexible, portable, and non-contact image capture, which enables many new applications and breathes new life into existing ones. However, camera-captured documents may suffer from distortions caused by non-planar document shape and perspective projection, which lead to failure of current OCR technologies. We present a geometric rectification framework for restoring the frontal-flat view of a document from a single camera-captured image. Our approach estimates 3D document shape from texture flow information obtained directly from the image without requiring additional 3D/metric data or prior camera calibration. Our framework provides a unified solution for both planar and curved documents and can be applied in many, especially mobile, camera-based document analysis applications. Experiments show that our method produces results that are significantly more OCR compatible than the original images. PMID:18276966

  5. Photorealistic image synthesis and camera validation from 2D images

    NASA Astrophysics Data System (ADS)

    Santos Ferrer, Juan C.; González Chévere, David; Manian, Vidya

    2014-06-01

    This paper presents a new 3D scene reconstruction technique using the Unity 3D game engine. The method presented here allow us to reconstruct the shape of simple objects and more complex ones from multiple 2D images, including infrared and digital images from indoor scenes and only digital images from outdoor scenes and then add the reconstructed object to the simulated scene created in Unity 3D, these scenes are then validated with real world scenes. The method used different cameras settings and explores different properties in the reconstructions of the scenes including light, color, texture, shapes and different views. To achieve the highest possible resolution, it was necessary the extraction of partial textures from visible surfaces. To recover the 3D shapes and the depth of simple objects that can be represented by the geometric bodies, there geometric characteristics were used. To estimate the depth of more complex objects the triangulation method was used, for this the intrinsic and extrinsic parameters were calculated using geometric camera calibration. To implement the methods mentioned above the Matlab tool was used. The technique presented here also let's us to simulate small simple videos, by reconstructing a sequence of multiple scenes of the video separated by small margins of time. To measure the quality of the reconstructed images and video scenes the Fast Low Band Model (FLBM) metric from the Video Quality Measurement (VQM) software was used. Low bandwidth perception based features include edges and motion.

  6. Image processing for cameras with fiber bundle image relay.

    PubMed

    Olivas, Stephen J; Arianpour, Ashkan; Stamenov, Igor; Morrison, Rick; Stack, Ron A; Johnson, Adam R; Agurok, Ilya P; Ford, Joseph E

    2015-02-10

    Some high-performance imaging systems generate a curved focal surface and so are incompatible with focal plane arrays fabricated by conventional silicon processing. One example is a monocentric lens, which forms a wide field-of-view high-resolution spherical image with a radius equal to the focal length. Optical fiber bundles have been used to couple between this focal surface and planar image sensors. However, such fiber-coupled imaging systems suffer from artifacts due to image sampling and incoherent light transfer by the fiber bundle as well as resampling by the focal plane, resulting in a fixed obscuration pattern. Here, we describe digital image processing techniques to improve image quality in a compact 126° field-of-view, 30 megapixel panoramic imager, where a 12 mm focal length F/1.35 lens made of concentric glass surfaces forms a spherical image surface, which is fiber-coupled to six discrete CMOS focal planes. We characterize the locally space-variant system impulse response at various stages: monocentric lens image formation onto the 2.5 μm pitch fiber bundle, image transfer by the fiber bundle, and sensing by a 1.75 μm pitch backside illuminated color focal plane. We demonstrate methods to mitigate moiré artifacts and local obscuration, correct for sphere to plane mapping distortion and vignetting, and stitch together the image data from discrete sensors into a single panorama. We compare processed images from the prototype to those taken with a 10× larger commercial camera with comparable field-of-view and light collection. PMID:25968031

  7. Update on High-Resolution Geodetically Controlled LROC Polar Mosaics

    NASA Astrophysics Data System (ADS)

    Archinal, B.; Lee, E.; Weller, L.; Richie, J.; Edmundson, K.; Laura, J.; Robinson, M.; Speyerer, E.; Boyd, A.; Bowman-Cisneros, E.; Wagner, R.; Nefian, A.

    2015-10-01

    We describe progress on high-resolution (1 m/pixel) geodetically controlled LROC mosaics of the lunar poles, which can be used for locating illumination resources (for solar power or cold traps) or landing site and surface operations planning.

  8. Evaluation of mobile phone camera benchmarking using objective camera speed and image quality metrics

    NASA Astrophysics Data System (ADS)

    Peltoketo, Veli-Tapani

    2014-11-01

    When a mobile phone camera is tested and benchmarked, the significance of image quality metrics is widely acknowledged. There are also existing methods to evaluate the camera speed. However, the speed or rapidity metrics of the mobile phone's camera system has not been used with the quality metrics even if the camera speed has become a more and more important camera performance feature. There are several tasks in this work. First, the most important image quality and speed-related metrics of a mobile phone's camera system are collected from the standards and papers and, also, novel speed metrics are identified. Second, combinations of the quality and speed metrics are validated using mobile phones on the market. The measurements are done toward application programming interface of different operating systems. Finally, the results are evaluated and conclusions are made. The paper defines a solution to combine different image quality and speed metrics to a single benchmarking score. A proposal of the combined benchmarking metric is evaluated using measurements of 25 mobile phone cameras on the market. The paper is a continuation of a previous benchmarking work expanded with visual noise measurement and updates of the latest mobile phone versions.

  9. An evolution of image source camera attribution approaches.

    PubMed

    Jahanirad, Mehdi; Wahab, Ainuddin Wahid Abdul; Anuar, Nor Badrul

    2016-05-01

    Camera attribution plays an important role in digital image forensics by providing the evidence and distinguishing characteristics of the origin of the digital image. It allows the forensic analyser to find the possible source camera which captured the image under investigation. However, in real-world applications, these approaches have faced many challenges due to the large set of multimedia data publicly available through photo sharing and social network sites, captured with uncontrolled conditions and undergone variety of hardware and software post-processing operations. Moreover, the legal system only accepts the forensic analysis of the digital image evidence if the applied camera attribution techniques are unbiased, reliable, nondestructive and widely accepted by the experts in the field. The aim of this paper is to investigate the evolutionary trend of image source camera attribution approaches from fundamental to practice, in particular, with the application of image processing and data mining techniques. Extracting implicit knowledge from images using intrinsic image artifacts for source camera attribution requires a structured image mining process. In this paper, we attempt to provide an introductory tutorial on the image processing pipeline, to determine the general classification of the features corresponding to different components for source camera attribution. The article also reviews techniques of the source camera attribution more comprehensively in the domain of the image forensics in conjunction with the presentation of classifying ongoing developments within the specified area. The classification of the existing source camera attribution approaches is presented based on the specific parameters, such as colour image processing pipeline, hardware- and software-related artifacts and the methods to extract such artifacts. The more recent source camera attribution approaches, which have not yet gained sufficient attention among image forensics

  10. NV-CMOS HD camera for day/night imaging

    NASA Astrophysics Data System (ADS)

    Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.

    2014-06-01

    SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE <90%), as well as projected low noise (<2h+) readout. Power consumption is minimized in the camera, which operates from a single 5V supply. The NVCMOS HD camera provides a substantial reduction in size, weight, and power (SWaP) , ideal for SWaP-constrained day/night imaging platforms such as UAVs, ground vehicles, fixed mount surveillance, and may be reconfigured for mobile soldier operations such as night vision goggles and weapon sights. In addition the camera with the NV-CMOS HD imager is suitable for high performance digital cinematography/broadcast systems, biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.

  11. Thermal analysis of the ultraviolet imager camera and electronics

    NASA Technical Reports Server (NTRS)

    Dirks, Gregory J.

    1991-01-01

    The Ultraviolet Imaging experiment has undergone design changes that necessiate updating the reduced thermal models (RTM's) for both the Camera and Electronics. In addition, there are several mission scenarios that need to be evaluated in terms of thermal response of the instruments. The impact of these design changes and mission scenarios on the thermal performance of the Camera and Electronics assemblies is discussed.

  12. Imaging Emission Spectra with Handheld and Cellphone Cameras

    ERIC Educational Resources Information Center

    Sitar, David

    2012-01-01

    As point-and-shoot digital camera technology advances it is becoming easier to image spectra in a laboratory setting on a shoestring budget and get immediate results. With this in mind, I wanted to test three cameras to see how their results would differ. Two undergraduate physics students and I used one handheld 7.1 megapixel (MP) digital Cannon…

  13. Why do the image widths from the various cameras change?

    Atmospheric Science Data Center

    2014-12-08

    ... change in relationship to the varying distance to the Earth for the different cameras. When viewing the same Earth area with a more ... only 250 m wide. Another factor affecting overlap is Earth rotation during the time interval between when each camera acquires its image ...

  14. Mobile phone camera benchmarking: combination of camera speed and image quality

    NASA Astrophysics Data System (ADS)

    Peltoketo, Veli-Tapani

    2014-01-01

    When a mobile phone camera is tested and benchmarked, the significance of quality metrics is widely acknowledged. There are also existing methods to evaluate the camera speed. For example, ISO 15781 defines several measurements to evaluate various camera system delays. However, the speed or rapidity metrics of the mobile phone's camera system have not been used with the quality metrics even if the camera speed has become more and more important camera performance feature. There are several tasks in this work. Firstly, the most important image quality metrics are collected from the standards and papers. Secondly, the speed related metrics of a mobile phone's camera system are collected from the standards and papers and also novel speed metrics are identified. Thirdly, combinations of the quality and speed metrics are validated using mobile phones in the market. The measurements are done towards application programming interface of different operating system. Finally, the results are evaluated and conclusions are made. The result of this work gives detailed benchmarking results of mobile phone camera systems in the market. The paper defines also a proposal of combined benchmarking metrics, which includes both quality and speed parameters.

  15. Motorized Panoramic Camera Mount - Calibration and Image Capture

    NASA Astrophysics Data System (ADS)

    Kauhanen, H.; Rönnholm, P.; Lehtola, V. V.

    2016-06-01

    interesting applications. Among the large variation of panoramic camera systems, we have focused on concentric panoramic imaging with a frame camera. In order to establish the concentric image acquisition, the camera mount must be calibrated so that the projection centre of the camera is located at the rotation centre of the mount. For this purpose, we developed a novel mount calibration method, which allows an accurate recovery of the rotation centre in two image acquisition steps. In addition, we have built a motorized camera mount that can self-calibrate the camera position within the mount, given the previously solved rotation centre, and then be used to automatically capture panoramic images. Hence, we have streamlined the previously laborious manual phase of iterative position calibration, but also automated the capturing of panoramic images. For validation purposes, reference results from a conventional manual mount are provided. In the case of non-motorized mount, the average distance between the projection centre of the camera and the rotation centre of the mount was 0.253 mm and the standard deviation was 0.161 mm. For the motorized mount, the corresponding average distance and standard deviation were 0.549 mm and 0.404 mm, respectively.

  16. Lucas-Kanade image registration using camera parameters

    NASA Astrophysics Data System (ADS)

    Cho, Sunghyun; Cho, Hojin; Tai, Yu-Wing; Moon, Young Su; Cho, Junguk; Lee, Shihwa; Lee, Seungyong

    2012-01-01

    The Lucas-Kanade algorithm and its variants have been successfully used for numerous works in computer vision, which include image registration as a component in the process. In this paper, we propose a Lucas-Kanade based image registration method using camera parameters. We decompose a homography into camera intrinsic and extrinsic parameters, and assume that the intrinsic parameters are given, e.g., from the EXIF information of a photograph. We then estimate only the extrinsic parameters for image registration, considering two types of camera motions, 3D rotations and full 3D motions with translations and rotations. As the known information about the camera is fully utilized, the proposed method can perform image registration more reliably. In addition, as the number of extrinsic parameters is smaller than the number of homography elements, our method runs faster than the Lucas-Kanade based registration method that estimates a homography itself.

  17. A time-resolved image sensor for tubeless streak cameras

    NASA Astrophysics Data System (ADS)

    Yasutomi, Keita; Han, SangMan; Seo, Min-Woong; Takasawa, Taishi; Kagawa, Keiichiro; Kawahito, Shoji

    2014-03-01

    This paper presents a time-resolved CMOS image sensor with draining-only modulation (DOM) pixels for tube-less streak cameras. Although the conventional streak camera has high time resolution, the device requires high voltage and bulky system due to the structure with a vacuum tube. The proposed time-resolved imager with a simple optics realize a streak camera without any vacuum tubes. The proposed image sensor has DOM pixels, a delay-based pulse generator, and a readout circuitry. The delay-based pulse generator in combination with an in-pixel logic allows us to create and to provide a short gating clock to the pixel array. A prototype time-resolved CMOS image sensor with the proposed pixel is designed and implemented using 0.11um CMOS image sensor technology. The image array has 30(Vertical) x 128(Memory length) pixels with the pixel pitch of 22.4um. .

  18. Application of the CCD camera in medical imaging

    NASA Astrophysics Data System (ADS)

    Chu, Wei-Kom; Smith, Chuck; Bunting, Ralph; Knoll, Paul; Wobig, Randy; Thacker, Rod

    1999-04-01

    Medical fluoroscopy is a set of radiological procedures used in medical imaging for functional and dynamic studies of digestive system. Major components in the imaging chain include image intensifier that converts x-ray information into an intensity pattern on its output screen and a CCTV camera that converts the output screen intensity pattern into video information to be displayed on a TV monitor. To properly respond to such a wide dynamic range on a real-time basis, such as fluoroscopy procedure, are very challenging. Also, similar to all other medical imaging studies, detail resolution is of great importance. Without proper contrast, spatial resolution is compromised. The many inherent advantages of CCD make it a suitable choice for dynamic studies. Recently, CCD camera are introduced as the camera of choice for medical fluoroscopy imaging system. The objective of our project was to investigate a newly installed CCD fluoroscopy system in areas of contrast resolution, details, and radiation dose.

  19. Altered Images: The Camera, Computer, & Beyond.

    ERIC Educational Resources Information Center

    Stieglitz, Mary

    The speech contained in this document originally accompanied a slide presentation on the altered photographic image. The discussion examines the links between photographic tradition and contemporary visual imaging, the current transformation of visual imaging by the computer, and the effects of digital imaging on visual arts. Photography has a…

  20. Autofluorescence imaging of basal cell carcinoma by smartphone RGB camera

    NASA Astrophysics Data System (ADS)

    Lihachev, Alexey; Derjabo, Alexander; Ferulova, Inesa; Lange, Marta; Lihacova, Ilze; Spigulis, Janis

    2015-12-01

    The feasibility of smartphones for in vivo skin autofluorescence imaging has been investigated. Filtered autofluorescence images from the same tissue area were periodically captured by a smartphone RGB camera with subsequent detection of fluorescence intensity decreasing at each image pixel for further imaging the planar distribution of those values. The proposed methodology was tested clinically with 13 basal cell carcinoma and 1 atypical nevus. Several clinical cases and potential future applications of the smartphone-based technique are discussed.

  1. ANIR: Atacama near infrared camera for Paschen α imaging

    NASA Astrophysics Data System (ADS)

    Motohara, Kentaro; Mitani, Natsuko; Sako, Shigeyuki; Uchimoto, Yuka K.; Toshikawa, Koji; Yamamuro, Tomoyasu; Handa, Toshihiro; Tanaka, Masuo; Aoki, Tsutomu; Doi, Mamoru; Kawara, Kimiaki; Kohno, Kotaro; Minezaki, Takeo; Miyata, Takashi; Soyano, Takao; Tanabe, Toshihiko; Tarusawa, Ken'ichi; Yoshii, Yuzuru

    2008-07-01

    We have been developing a near infrared camera called ANIR (Atacama Near InfraRed camera), for the University of Tokyo Atacama 1.0m telescope installed at the summit of Co. Chajnantor (5640m altitude) in Northern Chile. The major aim of this camera is to carry out an imaging survey in Paschen α emission line (1.8751μm) from the ground for the first time. The camera is based on a PACE-HAWAII2 array with an Offner relay optics for re-imaging, and field of view is 5.'3 × 5.'3 with pixel scale of 0."308/pix. It is scheduled to see first light in the end of 2008, and start the Paschen α/β survey of the Galactic plane in 2009.

  2. A fast, automatic camera image stabilization benchmarking scheme

    NASA Astrophysics Data System (ADS)

    Yu, Jun; Craver, Scott

    2012-01-01

    While image stabilization(IS ) has become a default functionality for most digital cameras, there is a lack of automatic IS evaluation scheme. Most publicly known camera IS reviews either require human visual assessment or resort to some generic blur metric. The former is slow and inconsistent, and the latter may not be easily scalable with respect to resolution variation and exposure variation when comparing different cameras. We proposed a histogram based automatic IS evaluation scheme, which employs a white noise pattern as shooting target. It is able to produce accurate and consistent IS benchmarks in a very fast manner.

  3. A design of camera simulator for photoelectric image acquisition system

    NASA Astrophysics Data System (ADS)

    Cai, Guanghui; Liu, Wen; Zhang, Xin

    2015-02-01

    In the process of developing the photoelectric image acquisition equipment, it needs to verify the function and performance. In order to make the photoelectric device recall the image data formerly in the process of debugging and testing, a design scheme of the camera simulator is presented. In this system, with FPGA as the control core, the image data is saved in NAND flash trough USB2.0 bus. Due to the access rate of the NAND, flash is too slow to meet the requirement of the sytsem, to fix the problem, the pipeline technique and the High-Band-Buses technique are applied in the design to improve the storage rate. It reads image data out from flash in the control logic of FPGA and output separately from three different interface of Camera Link, LVDS and PAL, which can provide image data for photoelectric image acquisition equipment's debugging and algorithm validation. However, because the standard of PAL image resolution is 720*576, the resolution is different between PAL image and input image, so the image can be output after the resolution conversion. The experimental results demonstrate that the camera simulator outputs three format image sequence correctly, which can be captured and displayed by frame gather. And the three-format image data can meet test requirements of the most equipment, shorten debugging time and improve the test efficiency.

  4. ProxiScan?: A Novel Camera for Imaging Prostate Cancer

    ScienceCinema

    Ralph James

    2010-01-08

    ProxiScan is a compact gamma camera suited for high-resolution imaging of prostate cancer. Developed by Brookhaven National Laboratory and Hybridyne Imaging Technologies, Inc., ProxiScan won a 2009 R&D 100 Award, sponsored by R&D Magazine to recognize t

  5. An airborne four-camera imaging system for agricultural applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the design and testing of an airborne multispectral digital imaging system for remote sensing applications. The system consists of four high resolution charge coupled device (CCD) digital cameras and a ruggedized PC equipped with a frame grabber and image acquisition software. T...

  6. ProxiScan™: A Novel Camera for Imaging Prostate Cancer

    SciTech Connect

    Ralph James

    2009-10-27

    ProxiScan is a compact gamma camera suited for high-resolution imaging of prostate cancer. Developed by Brookhaven National Laboratory and Hybridyne Imaging Technologies, Inc., ProxiScan won a 2009 R&D 100 Award, sponsored by R&D Magazine to recognize t

  7. Hyperspectral imaging camera using wavefront division interference.

    PubMed

    Bahalul, Eran; Bronfeld, Asaf; Epshtein, Shlomi; Saban, Yoram; Karsenty, Avi; Arieli, Yoel

    2016-03-01

    An approach for performing hyperspectral imaging is introduced. The hyperspectral imaging is based on Fourier transform spectroscopy, where the interference is performed by wavefront division interference rather than amplitude division interference. A variable phase delay between two parts of the wavefront emanating from each point of an object is created by a spatial light modulator (SLM) to obtain variable interference patterns. The SLM is placed in the exit pupil of an imaging system, thus enabling conversion of a general imaging optical system into an imaging hyperspectral optical system. The physical basis of the new approach is introduced, and an optical apparatus is built. PMID:26974085

  8. Opposition effect of the Moon from LROC WAC data

    NASA Astrophysics Data System (ADS)

    Velikodsky, Yu. I.; Korokhin, V. V.; Shkuratov, Yu. G.; Kaydash, V. G.; Videen, Gorden

    2016-09-01

    LROC WAC images acquired in 5 bands of the visible spectral range were used to study the opposition effect for two mare and two highland regions near the lunar equator. Opposition phase curves were extracted from the images containing the opposition by separating the phase-curve effect from the albedo pattern by comparing WAC images at different phase angles (from 0° to 30°). Akimov's photometric function and the NASA Digital Terrain Model GLD100 were used in the processing. It was found that phase-curve slopes at small phase angles directly correlate with albedo, while at larger phase angles, they are anti-correlated. We suggest a parameter to characterize the coherent-backscattering component of the lunar opposition surge, which is defined as the maximum phase angle for which the opposition-surge slope increases with growing albedo. The width of the coherent-backscattering opposition effect varies from approximately 1.2° for highlands in red light to 3.9° for maria in blue light. The parameter depends on albedo, which is in agreement with the coherent-backscattering theory. The maximum amplitude of the coherent opposition effect is estimated to be near 8%. Maps of albedo and phase-curve slope at phase angles larger than those, at which the coherent-backscattering occurs, were built for the areas under study. Absolute calibration of WAC images was compared with Earth-based observations: the WAC-determined albedo is very close to the mean lunar albedo calculated using available Earth-based observations.

  9. Volumetric particle image velocimetry with a single plenoptic camera

    NASA Astrophysics Data System (ADS)

    Fahringer, Timothy W.; Lynch, Kyle P.; Thurow, Brian S.

    2015-11-01

    A novel three-dimensional (3D), three-component (3C) particle image velocimetry (PIV) technique based on volume illumination and light field imaging with a single plenoptic camera is described. A plenoptic camera uses a densely packed microlens array mounted near a high resolution image sensor to sample the spatial and angular distribution of light collected by the camera. The multiplicative algebraic reconstruction technique (MART) computed tomography algorithm is used to reconstruct a volumetric intensity field from individual snapshots and a cross-correlation algorithm is used to estimate the velocity field from a pair of reconstructed particle volumes. This work provides an introduction to the basic concepts of light field imaging with a plenoptic camera and describes the unique implementation of MART in the context of plenoptic image data for 3D/3C PIV measurements. Simulations of a plenoptic camera using geometric optics are used to generate synthetic plenoptic particle images, which are subsequently used to estimate the quality of particle volume reconstructions at various particle number densities. 3D reconstructions using this method produce reconstructed particles that are elongated by a factor of approximately 4 along the optical axis of the camera. A simulated 3D Gaussian vortex is used to test the capability of single camera plenoptic PIV to produce a 3D/3C vector field, where it was found that lateral displacements could be measured to approximately 0.2 voxel accuracy in the lateral direction and 1 voxel in the depth direction over a 300× 200× 200 voxel volume. The feasibility of the technique is demonstrated experimentally using a home-built plenoptic camera based on a 16-megapixel interline CCD camera and a 289× 193 array of microlenses and a pulsed Nd:YAG laser. 3D/3C measurements were performed in the wake of a low Reynolds number circular cylinder and compared with measurements made using a conventional 2D/2C PIV system. Overall, single camera

  10. Applying image quality in cell phone cameras: lens distortion

    NASA Astrophysics Data System (ADS)

    Baxter, Donald; Goma, Sergio R.; Aleksic, Milivoje

    2009-01-01

    This paper describes the framework used in one of the pilot studies run under the I3A CPIQ initiative to quantify overall image quality in cell-phone cameras. The framework is based on a multivariate formalism which tries to predict overall image quality from individual image quality attributes and was validated in a CPIQ pilot program. The pilot study focuses on image quality distortions introduced in the optical path of a cell-phone camera, which may or may not be corrected in the image processing path. The assumption is that the captured image used is JPEG compressed and the cellphone camera is set to 'auto' mode. As the used framework requires that the individual attributes to be relatively perceptually orthogonal, in the pilot study, the attributes used are lens geometric distortion (LGD) and lateral chromatic aberrations (LCA). The goal of this paper is to present the framework of this pilot project starting with the definition of the individual attributes, up to their quantification in JNDs of quality, a requirement of the multivariate formalism, therefore both objective and subjective evaluations were used. A major distinction in the objective part from the 'DSC imaging world' is that the LCA/LGD distortions found in cell-phone cameras, rarely exhibit radial behavior, therefore a radial mapping/modeling cannot be used in this case.

  11. Efficient height measurement method of surveillance camera image.

    PubMed

    Lee, Joong; Lee, Eung-Dae; Tark, Hyun-Oh; Hwang, Jin-Woo; Yoon, Do-Young

    2008-05-01

    As surveillance cameras are increasingly installed, their films are often submitted as evidence of crime, but very scant detailed information such as features and clothes is obtained due to the limited camera performance. Height, however, is relatively not significantly influenced by the camera performance. This paper studied the height measurement method using images from a CCTV. The information on the height was obtained via photogrammetry, including the reference points in the photographed area and the calculation of the relationship between a 3D space and a 2D image through linear and nonlinear calibration. Using this correlation, this paper suggested the height measurement method, which projects a 3D virtual ruler onto the image. This method has been proven to offer more stable values within the range of data convergence than those of other existing methods. PMID:18096339

  12. Restoration of TDI camera images with motion distortion and blur

    NASA Astrophysics Data System (ADS)

    Wu, Jiagu; Zheng, Zhenzhen; Feng, Huajun; Xu, Zhihai; Li, qi; Chen, Yueting

    2010-11-01

    Platform movement during exposure of imaging system severely degrades image quality. In the case of Time delay and integration (TDI) camera, abnormal movements cause not only image blur but also distortion, for image Point Spread Function (PSF) is space-variant. In this paper, we present a motion degradation model of TDI image, and provide a method to restore such degraded image. While a TDI camera is imaging, it outputs images row by row (or line by line) along the scanning axis, and our method processes in the same track. We firstly calculate the space-invariant PSF of each row using the movement information of the TDI camera. Then, we substitute pixels of the row and the ones of their neighbor rows together with the PSF into standard Richardson-Lucy algorithm. By deconvoluting we get the restored pixels of the row. The same operations are executed for all rows of the degraded TDI image. Finally, a restored image can be reconstructed from those restored rows. Both simulated and experimental results prove the effectiveness of our method.

  13. Snapshot hyperspectral retinal camera with the Image Mapping Spectrometer (IMS)

    PubMed Central

    Gao, Liang; Smith, R. Theodore; Tkaczyk, Tomasz S.

    2011-01-01

    We present a snapshot hyperspectral retinal camera with the Image Mapping Spectrometer (IMS) for eye imaging applications. The resulting system is capable of simultaneously acquiring 48 spectral channel images in the range 470 nm–650 nm with frame rate at 5.2 fps. The spatial sampling of each measured spectral scene is 350 × 350 pixels. The advantages of this snapshot device are elimination of the eye motion artifacts and pixel misregistration problems in traditional scanning-based hyperspectral retinal cameras, and real-time imaging of oxygen saturation dynamics with sub-second temporal resolution. The spectral imaging performance is demonstrated in a human retinal imaging experiment in vivo. The absorption spectral signatures of oxy-hemoglobin and macular pigments were successfully acquired by using this device. PMID:22254167

  14. CMOS Image Sensors: Electronic Camera On A Chip

    NASA Technical Reports Server (NTRS)

    Fossum, E. R.

    1995-01-01

    Recent advancements in CMOS image sensor technology are reviewed, including both passive pixel sensors and active pixel sensors. On- chip analog to digital converters and on-chip timing and control circuits permit realization of an electronic camera-on-a-chip. Highly miniaturized imaging systems based on CMOS image sensor technology are emerging as a competitor to charge-coupled devices for low cost uses.

  15. High-Resolution Mars Camera Test Image of Moon (Infrared)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This crescent view of Earth's Moon in infrared wavelengths comes from a camera test by NASA's Mars Reconnaissance Orbiter spacecraft on its way to Mars. The mission's High Resolution Imaging Science Experiment camera took the image on Sept. 8, 2005, while at a distance of about 10 million kilometers (6 million miles) from the Moon. The dark feature on the right is Mare Crisium. From that distance, the Moon would appear as a star-like point of light to the unaided eye. The test verified the camera's focusing capability and provided an opportunity for calibration. The spacecraft's Context Camera and Optical Navigation Camera also performed as expected during the test.

    The Mars Reconnaissance Orbiter, launched on Aug. 12, 2005, is on course to reach Mars on March 10, 2006. After gradually adjusting the shape of its orbit for half a year, it will begin its primary science phase in November 2006. From the mission's planned science orbit about 300 kilometers (186 miles) above the surface of Mars, the high resolution camera will be able to discern features as small as one meter or yard across.

  16. Photogrammetric Processing of Apollo 15 Metric Camera Oblique Images

    NASA Astrophysics Data System (ADS)

    Edmundson, K. L.; Alexandrov, O.; Archinal, B. A.; Becker, K. J.; Becker, T. L.; Kirk, R. L.; Moratto, Z. M.; Nefian, A. V.; Richie, J. O.; Robinson, M. S.

    2016-06-01

    The integrated photogrammetric mapping system flown on the last three Apollo lunar missions (15, 16, and 17) in the early 1970s incorporated a Metric (mapping) Camera, a high-resolution Panoramic Camera, and a star camera and laser altimeter to provide support data. In an ongoing collaboration, the U.S. Geological Survey's Astrogeology Science Center, the Intelligent Robotics Group of the NASA Ames Research Center, and Arizona State University are working to achieve the most complete cartographic development of Apollo mapping system data into versatile digital map products. These will enable a variety of scientific/engineering uses of the data including mission planning, geologic mapping, geophysical process modelling, slope dependent correction of spectral data, and change detection. Here we describe efforts to control the oblique images acquired from the Apollo 15 Metric Camera.

  17. Compression of CCD raw images for digital still cameras

    NASA Astrophysics Data System (ADS)

    Sriram, Parthasarathy; Sudharsanan, Subramania

    2005-03-01

    Lossless compression of raw CCD images captured using color filter arrays has several benefits. The benefits include improved storage capacity, reduced memory bandwidth, and lower power consumption for digital still camera processors. The paper discusses the benefits in detail and proposes the use of a computationally efficient block adaptive scheme for lossless compression. Experimental results are provided that indicate that the scheme performs well for CCD raw images attaining compression factors of more than two. The block adaptive method also compares favorably with JPEG-LS. A discussion is provided indicating how the proposed lossless coding scheme can be incorporated into digital still camera processors enabling lower memory bandwidth and storage requirements.

  18. CMOS Imaging Sensor Technology for Aerial Mapping Cameras

    NASA Astrophysics Data System (ADS)

    Neumann, Klaus; Welzenbach, Martin; Timm, Martin

    2016-06-01

    In June 2015 Leica Geosystems launched the first large format aerial mapping camera using CMOS sensor technology, the Leica DMC III. This paper describes the motivation to change from CCD sensor technology to CMOS for the development of this new aerial mapping camera. In 2002 the DMC first generation was developed by Z/I Imaging. It was the first large format digital frame sensor designed for mapping applications. In 2009 Z/I Imaging designed the DMC II which was the first digital aerial mapping camera using a single ultra large CCD sensor to avoid stitching of smaller CCDs. The DMC III is now the third generation of large format frame sensor developed by Z/I Imaging and Leica Geosystems for the DMC camera family. It is an evolution of the DMC II using the same system design with one large monolithic PAN sensor and four multi spectral camera heads for R,G, B and NIR. For the first time a 391 Megapixel large CMOS sensor had been used as PAN chromatic sensor, which is an industry record. Along with CMOS technology goes a range of technical benefits. The dynamic range of the CMOS sensor is approx. twice the range of a comparable CCD sensor and the signal to noise ratio is significantly better than with CCDs. Finally results from the first DMC III customer installations and test flights will be presented and compared with other CCD based aerial sensors.

  19. Cheetah: A high frame rate, high resolution SWIR image camera

    NASA Astrophysics Data System (ADS)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  20. Air Pollution Determination Using a Surveillance Internet Protocol Camera Images

    NASA Astrophysics Data System (ADS)

    Chow Jeng, C. J.; Hwee San, Hslim; Matjafri, M. Z.; Abdullah, Abdul, K.

    Air pollution has long been a problem in the industrial nations of the West It has now become an increasing source of environmental degradation in the developing nations of east Asia Malaysia government has built a network to monitor air pollution But the cost of these networks is high and limits the knowledge of pollutant concentration to specific points of the cities A methodology based on a surveillance internet protocol IP camera for the determination air pollution concentrations was presented in this study The objective of this study was to test the feasibility of using IP camera data for estimating real time particulate matter of size less than 10 micron PM10 in the campus of USM The proposed PM10 retrieval algorithm derived from the atmospheric optical properties was employed in the present study In situ data sets of PM10 measurements and sun radiation measurements at the ground surface were collected simultaneously with the IP camera images using a DustTrak meter and a handheld spectroradiometer respectively The digital images were separated into three bands namely red green and blue bands for multispectral algorithm calibration The digital number DN of the IP camera images were converted into radiance and reflectance values After that the reflectance recorded by the digital camera was subtracted by the reflectance of the known surface and we obtained the reflectance caused by the atmospheric components The atmospheric reflectance values were used for regression analysis Regression technique was employed to determine suitable

  1. Visible camera imaging of plasmas in Proto-MPEX

    NASA Astrophysics Data System (ADS)

    Mosby, R.; Skeen, C.; Biewer, T. M.; Renfro, R.; Ray, H.; Shaw, G. C.

    2015-11-01

    The prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma device being developed at Oak Ridge National Laboratory (ORNL). This machine plans to study plasma-material interaction (PMI) physics relevant to future fusion reactors. Measurements of plasma light emission will be made on Proto-MPEX using fast, visible framing cameras. The cameras utilize a global shutter, which allows a full frame image of the plasma to be captured and compared at multiple times during the plasma discharge. Typical exposure times are ~10-100 microseconds. The cameras are capable of capturing images at up to 18,000 frames per second (fps). However, the frame rate is strongly dependent on the size of the ``region of interest'' that is sampled. The maximum ROI corresponds to the full detector area, of ~1000x1000 pixels. The cameras have an internal gain, which controls the sensitivity of the 10-bit detector. The detector includes a Bayer filter, for ``true-color'' imaging of the plasma emission. This presentation will exmine the optimized camera settings for use on Proto-MPEX. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.

  2. Practical solution to authentication of images with a secure camera

    NASA Astrophysics Data System (ADS)

    Quisquater, Jean-Jacques; Macq, Benoit M. M.; Joye, M.; Degand, N.; Bernard, A.

    1997-01-01

    Those who have seen the move Forrest Gump witnessed former U.S. President J.F. Kennedy shaking the hand of Tom Hanks. Nevertheless, they have never met. Though this image seems real, how can we be certain it is not? How long can we still believe the images? This paper presents an efficient system guaranteeing to detect whether the images of an original video sequence have been modified between the original recording and the moment of viewing. Moreover, it takes into account the intervention of an editor between the original recording and the projection. Whatever is the final edited tape, the cryptographic information generated by the camera allows to authenticate the images of the editing. This scheme is dedicated to images coming from digital cameras using the DV format but can be extended to any other standard.

  3. Establishing imaging sensor specifications for digital still cameras

    NASA Astrophysics Data System (ADS)

    Kriss, Michael A.

    2007-02-01

    Digital Still Cameras, DSCs, have now displaced conventional still cameras in most markets. The heart of a DSC is thought to be the imaging sensor, be it Full Frame CCD, and Interline CCD, a CMOS sensor or the newer Foveon buried photodiode sensors. There is a strong tendency by consumers to consider only the number of mega-pixels in a camera and not to consider the overall performance of the imaging system, including sharpness, artifact control, noise, color reproduction, exposure latitude and dynamic range. This paper will provide a systematic method to characterize the physical requirements of an imaging sensor and supporting system components based on the desired usage. The analysis is based on two software programs that determine the "sharpness", potential for artifacts, sensor "photographic speed", dynamic range and exposure latitude based on the physical nature of the imaging optics, sensor characteristics (including size of pixels, sensor architecture, noise characteristics, surface states that cause dark current, quantum efficiency, effective MTF, and the intrinsic full well capacity in terms of electrons per square centimeter). Examples will be given for consumer, pro-consumer, and professional camera systems. Where possible, these results will be compared to imaging system currently on the market.

  4. Inexpensive Neutron Imaging Cameras Using CCDs for Astronomy

    NASA Astrophysics Data System (ADS)

    Hewat, A. W.

    We have developed inexpensive neutron imaging cameras using CCDs originally designed for amateur astronomical observation. The low-light, high resolution requirements of such CCDs are similar to those for neutron imaging, except that noise as well as cost is reduced by using slower read-out electronics. For example, we use the same 2048x2048 pixel "Kodak" KAI-4022 CCD as used in the high performance PCO-2000 CCD camera, but our electronics requires ∼5 sec for full-frame read-out, ten times slower than the PCO-2000. Since neutron exposures also require several seconds, this is not seen as a serious disadvantage for many applications. If higher frame rates are needed, the CCD unit on our camera can be easily swapped for a faster readout detector with similar chip size and resolution, such as the PCO-2000 or the sCMOS PCO.edge 4.2.

  5. Multi-spectral image dissector camera system

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The image dissector sensor for the Earth Resources Program is evaluated using contrast and reflectance data. The ground resolution obtainable for low contrast at the targeted signal to noise ratio of 1.8 was defined. It is concluded that the system is capable of achieving the detection of small, low contrast ground targets from satellites.

  6. Digital camera with apparatus for authentication of images produced from an image file

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L. (Inventor)

    1993-01-01

    A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely based upon the private key that digital data encrypted with the private key by the processor may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating at any time the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match, since even one bit change in the image hash will cause the image hash to be totally different from the secure hash.

  7. Image quality testing of assembled IR camera modules

    NASA Astrophysics Data System (ADS)

    Winters, Daniel; Erichsen, Patrik

    2013-10-01

    Infrared (IR) camera modules for the LWIR (8-12_m) that combine IR imaging optics with microbolometer focal plane array (FPA) sensors with readout electronics are becoming more and more a mass market product. At the same time, steady improvements in sensor resolution in the higher priced markets raise the requirement for imaging performance of objectives and the proper alignment between objective and FPA. This puts pressure on camera manufacturers and system integrators to assess the image quality of finished camera modules in a cost-efficient and automated way for quality control or during end-of-line testing. In this paper we present recent development work done in the field of image quality testing of IR camera modules. This technology provides a wealth of additional information in contrast to the more traditional test methods like minimum resolvable temperature difference (MRTD) which give only a subjective overall test result. Parameters that can be measured are image quality via the modulation transfer function (MTF) for broadband or with various bandpass filters on- and off-axis and optical parameters like e.g. effective focal length (EFL) and distortion. If the camera module allows for refocusing the optics, additional parameters like best focus plane, image plane tilt, auto-focus quality, chief ray angle etc. can be characterized. Additionally, the homogeneity and response of the sensor with the optics can be characterized in order to calculate the appropriate tables for non-uniformity correction (NUC). The technology can also be used to control active alignment methods during mechanical assembly of optics to high resolution sensors. Other important points that are discussed are the flexibility of the technology to test IR modules with different form factors, electrical interfaces and last but not least the suitability for fully automated measurements in mass production.

  8. A compact gamma camera for biological imaging

    SciTech Connect

    Bradley, E L; Cella, J; Majewski, S; Popov, V; Qian, Jianguo; Saha, M S; Smith, M F; Weisenberger, A G; Welsh, R E

    2006-02-01

    A compact detector, sized particularly for imaging a mouse, is described. The active area of the detector is approximately 46 mm; spl times/ 96 mm. Two flat-panel Hamamatsu H8500 position-sensitive photomultiplier tubes (PSPMTs) are coupled to a pixellated NaI(Tl) scintillator which views the animal through a copper-beryllium (CuBe) parallel-hole collimator specially designed for {sup 125}I. Although the PSPMTs have insensitive areas at their edges and there is a physical gap, corrections for scintillation light collection at the junction between the two tubes results in a uniform response across the entire rectangular area of the detector. The system described has been developed to optimize both sensitivity and resolution for in-vivo imaging of small animals injected with iodinated compounds. We demonstrate an in-vivo application of this detector, particularly to SPECT, by imaging mice injected with approximately 10-15; spl mu/Ci of {sup 125}I.

  9. Dual camera system for acquisition of high resolution images

    NASA Astrophysics Data System (ADS)

    Papon, Jeremie A.; Broussard, Randy P.; Ives, Robert W.

    2007-02-01

    Video surveillance is ubiquitous in modern society, but surveillance cameras are severely limited in utility by their low resolution. With this in mind, we have developed a system that can autonomously take high resolution still frame images of moving objects. In order to do this, we combine a low resolution video camera and a high resolution still frame camera mounted on a pan/tilt mount. In order to determine what should be photographed (objects of interest), we employ a hierarchical method which first separates foreground from background using a temporal-based median filtering technique. We then use a feed-forward neural network classifier on the foreground regions to determine whether the regions contain the objects of interest. This is done over several frames, and a motion vector is deduced for the object. The pan/tilt mount then focuses the high resolution camera on the next predicted location of the object, and an image is acquired. All components are controlled through a single MATLAB graphical user interface (GUI). The final system we present will be able to detect multiple moving objects simultaneously, track them, and acquire high resolution images of them. Results will demonstrate performance tracking and imaging varying numbers of objects moving at different speeds.

  10. Coincidence ion imaging with a fast frame camera

    SciTech Connect

    Lee, Suk Kyoung; Cudry, Fadia; Lin, Yun Fei; Lingenfelter, Steven; Winney, Alexander H.; Fan, Lin; Li, Wen

    2014-12-15

    A new time- and position-sensitive particle detection system based on a fast frame CMOS (complementary metal-oxide semiconductors) camera is developed for coincidence ion imaging. The system is composed of four major components: a conventional microchannel plate/phosphor screen ion imager, a fast frame CMOS camera, a single anode photomultiplier tube (PMT), and a high-speed digitizer. The system collects the positional information of ions from a fast frame camera through real-time centroiding while the arrival times are obtained from the timing signal of a PMT processed by a high-speed digitizer. Multi-hit capability is achieved by correlating the intensity of ion spots on each camera frame with the peak heights on the corresponding time-of-flight spectrum of a PMT. Efficient computer algorithms are developed to process camera frames and digitizer traces in real-time at 1 kHz laser repetition rate. We demonstrate the capability of this system by detecting a momentum-matched co-fragments pair (methyl and iodine cations) produced from strong field dissociative double ionization of methyl iodide.

  11. Coincidence electron/ion imaging with a fast frame camera

    NASA Astrophysics Data System (ADS)

    Li, Wen; Lee, Suk Kyoung; Lin, Yun Fei; Lingenfelter, Steven; Winney, Alexander; Fan, Lin

    2015-05-01

    A new time- and position- sensitive particle detection system based on a fast frame CMOS camera is developed for coincidence electron/ion imaging. The system is composed of three major components: a conventional microchannel plate (MCP)/phosphor screen electron/ion imager, a fast frame CMOS camera and a high-speed digitizer. The system collects the positional information of ions/electrons from a fast frame camera through real-time centroiding while the arrival times are obtained from the timing signal of MCPs processed by a high-speed digitizer. Multi-hit capability is achieved by correlating the intensity of electron/ion spots on each camera frame with the peak heights on the corresponding time-of-flight spectrum. Efficient computer algorithms are developed to process camera frames and digitizer traces in real-time at 1 kHz laser repetition rate. We demonstrate the capability of this system by detecting a momentum-matched co-fragments pair (methyl and iodine cations) produced from strong field dissociative double ionization of methyl iodide. We further show that a time resolution of 30 ps can be achieved when measuring electron TOF spectrum and this enables the new system to achieve a good energy resolution along the TOF axis.

  12. Image-based camera motion estimation using prior probabilities

    NASA Astrophysics Data System (ADS)

    Sargent, Dusty; Park, Sun Young; Spofford, Inbar; Vosburgh, Kirby

    2011-03-01

    Image-based camera motion estimation from video or still images is a difficult problem in the field of computer vision. Many algorithms have been proposed for estimating intrinsic camera parameters, detecting and matching features between images, calculating extrinsic camera parameters based on those features, and optimizing the recovered parameters with nonlinear methods. These steps in the camera motion inference process all face challenges in practical applications: locating distinctive features can be difficult in many types of scenes given the limited capabilities of current feature detectors, camera motion inference can easily fail in the presence of noise and outliers in the matched features, and the error surfaces in optimization typically contain many suboptimal local minima. The problems faced by these techniques are compounded when they are applied to medical video captured by an endoscope, which presents further challenges such as non-rigid scenery and severe barrel distortion of the images. In this paper, we study these problems and propose the use of prior probabilities to stabilize camera motion estimation for the application of computing endoscope motion sequences in colonoscopy. Colonoscopy presents a special case for camera motion estimation in which it is possible to characterize typical motion sequences of the endoscope. As the endoscope is restricted to move within a roughly tube-shaped structure, forward/backward motion is expected, with only small amounts of rotation and horizontal movement. We formulate a probabilistic model of endoscope motion by maneuvering an endoscope and attached magnetic tracker through a synthetic colon model and fitting a distribution to the observed motion of the magnetic tracker. This model enables us to estimate the probability of the current endoscope motion given previously observed motion in the sequence. We add these prior probabilities into the camera motion calculation as an additional penalty term in RANSAC

  13. Multiexposure and multifocus image fusion with multidimensional camera shake compensation

    NASA Astrophysics Data System (ADS)

    Gomez, Alexis Lluis; Saravi, Sara; Edirisinghe, Eran A.

    2013-10-01

    Multiexposure image fusion algorithms are used for enhancing the perceptual quality of an image captured by sensors of limited dynamic range. This is achieved by rendering a single scene based on multiple images captured at different exposure times. Similarly, multifocus image fusion is used when the limited depth of focus on a selected focus setting of a camera results in parts of an image being out of focus. The solution adopted is to fuse together a number of multifocus images to create an image that is focused throughout. A single algorithm that can perform both multifocus and multiexposure image fusion is proposed. This algorithm is a new approach in which a set of unregistered multiexposure/focus images is first registered before being fused to compensate for the possible presence of camera shake. The registration of images is done via identifying matching key-points in constituent images using scale invariant feature transforms. The random sample consensus algorithm is used to identify inliers of SIFT key-points removing outliers that can cause errors in the registration process. Finally, the coherent point drift algorithm is used to register the images, preparing them to be fused in the subsequent fusion stage. For the fusion of images, a new approach based on an improved version of a wavelet-based contourlet transform is used. The experimental results and the detailed analysis presented prove that the proposed algorithm is capable of producing high-dynamic range (HDR) or multifocus images by registering and fusing a set of multiexposure or multifocus images taken in the presence of camera shake. Further, comparison of the performance of the proposed algorithm with a number of state-of-the art algorithms and commercial software packages is provided. In particular, our literature review has revealed that this is one of the first attempts where the compensation of camera shake, a very likely practical problem that can result in HDR image capture using

  14. Laser Imaging Video Camera Sees Through Fire, Fog, Smoke

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Under a series of SBIR contracts with Langley Research Center, inventor Richard Billmers refined a prototype for a laser imaging camera capable of seeing through fire, fog, smoke, and other obscurants. Now, Canton, Ohio-based Laser Imaging through Obscurants (LITO) Technologies Inc. is demonstrating the technology as a perimeter security system at Glenn Research Center and planning its future use in aviation, shipping, emergency response, and other fields.

  15. Radiometric cloud imaging with an uncooled microbolometer thermal infrared camera.

    PubMed

    Shaw, Joseph; Nugent, Paul; Pust, Nathan; Thurairajah, Brentha; Mizutani, Kohei

    2005-07-25

    An uncooled microbolometer-array thermal infrared camera has been incorporated into a remote sensing system for radiometric sky imaging. The radiometric calibration is validated and improved through direct comparison with spectrally integrated data from the Atmospheric Emitted Radiance Interferometer (AERI). With the improved calibration, the Infrared Cloud Imager (ICI) system routinely obtains sky images with radiometric uncertainty less than 0.5 W/(m(2 )sr) for extended deployments in challenging field environments. We demonstrate the infrared cloud imaging technique with still and time-lapse imagery of clear and cloudy skies, including stratus, cirrus, and wave clouds. PMID:19498585

  16. Copernican craters: Early results from the Lunar Reconnaissance Orbiter Camera

    NASA Astrophysics Data System (ADS)

    McEwen, A. S.; Hiesinger, H.; Thomas, P. C.; Robinson, M. S.; van der Bogert, C.; Ostrach, L.; Plescia, J. B.; Bray, V. J.; Tornabene, L. L.

    2009-12-01

    The youngest (Copernican) craters on the Moon provide the best examples of original crater morphology and a record of the impact flux over the last ~1 Ga in the Earth-Moon system. The LRO Narrow Angle Cameras (NAC) provide 50 cm pixels from an altitude of 50 km. With changing incidence angle, global access, and very high data rates, these cameras provide unprecedented data on lunar craters. Stereo image pairs are being acquired for detailed topographic mapping. These data allow comparisons of relative ages of the larger young craters, some of which are tied to absolute radiometric ages from Apollo-returned samples. These relative ages, the crater populations at small diameters, and details of crater morphology including ejecta and melt morphologies, allow better delineation of recent lunar history and the formation and modification of impact craters. Crater counts may also reveal differences in the formation and preservation of small diameter craters as a function of target material (e.g., unconsolidated regolith versus solid impact melt). One key question: Is the current cratering rate constant or does it fluctuate. We will constrain the very recent cratering rate (at 10-100 m diameter) by comparing LROC images with those taken by Apollo nearly 40 years ago to determine the number of new impact craters. The current cratering rate and an assumption of constant cratering rate over time may or may not correctly predict the number of craters superimposed over radiometrically-dated surfaces such as South Ray, Cone, and North Ray craters, which range from 2-50 Ma and are not saturated by 10-100 m craters. If the prediction fails with realistic consideration of errors, then the present-day cratering rate must be atypical. Secondary craters complicate this analysis, but the resolution and coverage of LROC enables improved recognition of secondary craters. Of particular interest for the youngest Copernican craters is the possibility of self-cratering. LROC is providing the

  17. Digital Camera with Apparatus for Authentication of Images Produced from an Image File

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L. (Inventor)

    1996-01-01

    A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely related to the private key that digital data encrypted with the private key may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The authenticating apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match. Other techniques to address time-honored methods of deception, such as attaching false captions or inducing forced perspectives, are included.

  18. Fast Source Camera Identification Using Content Adaptive Guided Image Filter.

    PubMed

    Zeng, Hui; Kang, Xiangui

    2016-03-01

    Source camera identification (SCI) is an important topic in image forensics. One of the most effective fingerprints for linking an image to its source camera is the sensor pattern noise, which is estimated as the difference between the content and its denoised version. It is widely believed that the performance of the sensor-based SCI heavily relies on the denoising filter used. This study proposes a novel sensor-based SCI method using content adaptive guided image filter (CAGIF). Thanks to the low complexity nature of the CAGIF, the proposed method is much faster than the state-of-the-art methods, which is a big advantage considering the potential real-time application of SCI. Despite the advantage of speed, experimental results also show that the proposed method can achieve comparable or better performance than the state-of-the-art methods in terms of accuracy. PMID:27404627

  19. A novel SPECT camera for molecular imaging of the prostate

    NASA Astrophysics Data System (ADS)

    Cebula, Alan; Gilland, David; Su, Li-Ming; Wagenaar, Douglas; Bahadori, Amir

    2011-10-01

    The objective of this work is to develop an improved SPECT camera for dedicated prostate imaging. Complementing the recent advancements in agents for molecular prostate imaging, this device has the potential to assist in distinguishing benign from aggressive cancers, to improve site-specific localization of cancer, to improve accuracy of needle-guided prostate biopsy of cancer sites, and to aid in focal therapy procedures such as cryotherapy and radiation. Theoretical calculations show that the spatial resolution/detection sensitivity of the proposed SPECT camera can rival or exceed 3D PET and further signal-to-noise advantage is attained with the better energy resolution of the CZT modules. Based on photon transport simulation studies, the system has a reconstructed spatial resolution of 4.8 mm with a sensitivity of 0.0001. Reconstruction of a simulated prostate distribution demonstrates the focal imaging capability of the system.

  20. Surveillance of the plant growth using the camera image

    NASA Astrophysics Data System (ADS)

    Fujiwara, Nobuyuki; Terada, Kenji

    2005-12-01

    In this paper, we propose a method of surveillance of the plant growth using the camera image. This method is able to observe the condition of raising the plant in the greenhouse. The plate which is known as HORIBA is prepared for extracting harmful insect. The image of HORIBA is obtained by the camera and used for processing. The resolution of the image is 1280×960. In first process, region of the harmful insect (fly) is extracted from HORIBA by using color information. In next process the template matching is performed to examine the correlation of shape in four different angles. 16 kinds of results are obtained by four different templates. The sum logical of the results is calculated for estimation. In addition, the experimental results are shown in this paper.

  1. A CMOS image sensor dedicated to medical gamma camera application

    NASA Astrophysics Data System (ADS)

    Salahuddin, Nur S.; Paindavoine, Michel; Ginhac, Dominique; Parmentier, Michel; Tamda, Najia

    2005-03-01

    Generally, medical Gamma Camera are based on the Anger principle. These cameras use a scintillator block coupled to a bulky array of photomultiplier tube (PMT). To simplify this, we designed a new integrated CMOS image sensor in order to replace bulky PMT photodetetors. We studied several photodiodes sensors including current mirror amplifiers. These photodiodes have been fabricated using a CMOS 0.6 micrometers process from Austria Mikro Systeme (AMS). Each sensor pixel in the array occupies respectively, 1mm x 1mm area, 0.5mm x 0.5mm area and 0.2mm 0.2mm area with fill factor 98 % and total chip area is 2 square millimeters. The sensor pixels show a logarithmic response in illumination and are capable of detecting very low green light emitting diode (less than 0.5 lux) . These results allow to use our sensor in new Gamma Camera solid-state concept.

  2. Measuring SO2 ship emissions with an ultraviolet imaging camera

    NASA Astrophysics Data System (ADS)

    Prata, A. J.

    2014-05-01

    Over the last few years fast-sampling ultraviolet (UV) imaging cameras have been developed for use in measuring SO2 emissions from industrial sources (e.g. power plants; typical emission rates ~ 1-10 kg s-1) and natural sources (e.g. volcanoes; typical emission rates ~ 10-100 kg s-1). Generally, measurements have been made from sources rich in SO2 with high concentrations and emission rates. In this work, for the first time, a UV camera has been used to measure the much lower concentrations and emission rates of SO2 (typical emission rates ~ 0.01-0.1 kg s-1) in the plumes from moving and stationary ships. Some innovations and trade-offs have been made so that estimates of the emission rates and path concentrations can be retrieved in real time. Field experiments were conducted at Kongsfjord in Ny Ålesund, Svalbard, where SO2 emissions from cruise ships were made, and at the port of Rotterdam, Netherlands, measuring emissions from more than 10 different container and cargo ships. In all cases SO2 path concentrations could be estimated and emission rates determined by measuring ship plume speeds simultaneously using the camera, or by using surface wind speed data from an independent source. Accuracies were compromised in some cases because of the presence of particulates in some ship emissions and the restriction of single-filter UV imagery, a requirement for fast-sampling (> 10 Hz) from a single camera. Despite the ease of use and ability to determine SO2 emission rates from the UV camera system, the limitation in accuracy and precision suggest that the system may only be used under rather ideal circumstances and that currently the technology needs further development to serve as a method to monitor ship emissions for regulatory purposes. A dual-camera system or a single, dual-filter camera is required in order to properly correct for the effects of particulates in ship plumes.

  3. Sub-100g uncooled thermal imaging camera design

    NASA Astrophysics Data System (ADS)

    Brown, Alistair

    2008-10-01

    There are many applications for thermal imaging systems where low weight, high performance and high durability are at a premium. These include UAV systems, future warrior programs and thermal weapon sights. Thermal imaging camera design is restricted by a number external constraints including, detector packaging, detector performance and optical design. This paper describes how, by combining the latest 25µm pitch detector technology, novel optical design and shutter-less image processing a high resolution imager a system weight of 100g can be achieved. Recently developed detectors have low mass vacuum packages, in this example a 384x288 25um un-cooled microbolometer has a weight of less than 25g. By comparison, earlier 35µm and 50 µm devices were In the region of 40g. Where cameras are used in harsh environments mechanical shutters present both a reliability issue and additional weight. The low-weight camera utilises Xti Shutter-less technology to generate high quality images without the need for any form of mechanical shutter. The resulting camera has no moving parts. Lenses for Long Wave Infrared (LWIR) Thermal imaging are typically manufactured using Germanium (Ge) elements. These lenses tend to be designed with f/1.0 apertures and as a result add significant weight to the design. Thanks to the smaller detector pitch and system sensitivity a lens has been designed with a focal length of 14.95mm at f/1.3 where the mass of the optical components is 9g. The final optical assembly, including passive athermalisation has a mass of no more than 15g.

  4. Innovative Camera and Image Processing System to Characterize Cryospheric Changes

    NASA Astrophysics Data System (ADS)

    Schenk, A.; Csatho, B. M.; Nagarajan, S.

    2010-12-01

    The polar regions play an important role in Earth’s climatic and geodynamic systems. Digital photogrammetric mapping provides a means for monitoring the dramatic changes observed in the polar regions during the past decades. High-resolution, photogrammetrically processed digital aerial imagery provides complementary information to surface measurements obtained by laser altimetry systems. While laser points accurately sample the ice surface, stereo images allow for the mapping of features, such as crevasses, flow bands, shear margins, moraines, leads, and different types of sea ice. Tracking features in repeat images produces a dense velocity vector field that can either serve as validation for interferometrically derived surface velocities or it constitutes a stand-alone product. A multi-modal, photogrammetric platform consists of one or more high-resolution, commercial color cameras, GPS and inertial navigation system as well as optional laser scanner. Such a system, using a Canon EOS-1DS Mark II camera, was first flown on the Icebridge missions Fall 2009 and Spring 2010, capturing hundreds of thousands of images at a frame rate of about one second. While digital images and videos have been used for quite some time for visual inspection, precise 3D measurements with low cost, commercial cameras require special photogrammetric treatment that only became available recently. Calibrating the multi-camera imaging system and geo-referencing the images are absolute prerequisites for all subsequent applications. Commercial cameras are inherently non-metric, that is, their sensor model is only approximately known. Since these cameras are not as rugged as photogrammetric cameras, the interior orientation also changes, due to temperature and pressure changes and aircraft vibration, resulting in large errors in 3D measurements. It is therefore necessary to calibrate the cameras frequently, at least whenever the system is newly installed. Geo-referencing the images is

  5. Mini-RF and LROC observations of mare crater layering relationships

    NASA Astrophysics Data System (ADS)

    Stickle, A. M.; Patterson, G. W.; Cahill, J. T. S.; Bussey, D. B. J.

    2016-07-01

    The lunar maria cover approximately 17% of the Moon's surface. Discerning discrete subsurface layers in the mare provides some constraints on thickness and volume estimates of mare volcanism. Multiple types of data and measurement techniques allow probing the subsurface and provide insights into these layers, including detailed examination of impact craters, mare pits and sinuous rilles, and radar sounders. Unfortunately, radar sounding includes many uncertainties about the material properties of the lunar surface that may influence estimates of layer depth and thickness. Because they distribute material from depth onto the surface, detailed examination of impact ejecta blankets provides a reliable way to examine deeper material using orbital instruments such as cameras, spectrometers, or imaging radars. Here, we utilize Miniature Radio Frequency (Mini-RF) data to investigate the scattering characteristics of ejecta blankets of young lunar craters. We use Circular Polarization Ratio (CPR) information from twenty-two young, fresh lunar craters to examine how the scattering behavior changes as a function of radius from the crater rim. Observations across a range of crater size and relative ages exhibit significant diversity within mare regions. Five of the examined craters exhibit profiles with no shelf of constant CPR near the crater rim. Comparing these CPR profiles with LROC imagery shows that the magnitude of the CPR may be an indication of crater degradation state; this may manifest differently at radar compared to optical wavelengths. Comparisons of radar and optical data also suggest relationships between subsurface stratigraphy and structure in the mare and the block size of the material found within the ejecta blanket. Of the examined craters, twelve have shelves of approximately constant CPR as well as discrete layers outcropping in the subsurface, and nine fall along a trend line when comparing shelf-width with thickness of subsurface layers. These

  6. Characterization of a PET Camera Optimized for ProstateImaging

    SciTech Connect

    Huber, Jennifer S.; Choong, Woon-Seng; Moses, William W.; Qi,Jinyi; Hu, Jicun; Wang, G.C.; Wilson, David; Oh, Sang; Huesman, RonaldH.; Derenzo, Stephen E.

    2005-11-11

    We present the characterization of a positron emission tomograph for prostate imaging that centers a patient between a pair of external curved detector banks (ellipse: 45 cm minor, 70 cm major axis). The distance between detector banks adjusts to allow patient access and to position the detectors as closely as possible for maximum sensitivity with patients of various sizes. Each bank is composed of two axial rows of 20 HR+ block detectors for a total of 80 detectors in the camera. The individual detectors are angled in the transaxial plane to point towards the prostate to reduce resolution degradation in that region. The detectors are read out by modified HRRT data acquisition electronics. Compared to a standard whole-body PET camera, our dedicated-prostate camera has the same sensitivity and resolution, less background (less randoms and lower scatter fraction) and a lower cost. We have completed construction of the camera. Characterization data and reconstructed images of several phantoms are shown. Sensitivity of a point source in the center is 946 cps/mu Ci. Spatial resolution is 4 mm FWHM in the central region.

  7. Camera assembly design proposal for SRF cavity image collection

    SciTech Connect

    Tuozzolo, S.

    2011-10-10

    This project seeks to collect images from the inside of a superconducting radio frequency (SRF) large grain niobium cavity during vertical testing. These images will provide information on multipacting and other phenomena occurring in the SRF cavity during these tests. Multipacting, a process that involves an electron buildup in the cavity and concurrent loss of RF power, is thought to be occurring near the cathode in the SRF structure. Images of electron emission in the structure will help diagnose the source of multipacting in the cavity. Multipacting sources may be eliminated with an alteration of geometric or resonant conditions in the SRF structure. Other phenomena, including unexplained light emissions previously discovered at SLAC, may be present in the cavity. In order to effectively capture images of these events during testing, a camera assembly needs to be installed to the bottom of the RF structure. The SRF assembly operates under extreme environmental conditions: it is kept in a dewar in a bath of 2K liquid helium during these tests, is pumped down to ultra-high vacuum, and is subjected to RF voltages. Because of this, the camera needs to exist as a separate assembly attached to the bottom of the cavity. The design of the camera is constrained by a number of factors that are discussed.

  8. Single-photon imaging camera development for night vision

    NASA Astrophysics Data System (ADS)

    Vasile, Stefan; Cheng, Jing; Lipson, Jerold; Liu, Jifeng; Michel, Jurgen

    2010-04-01

    Single-photon imaging in infrared will add a new valuable tool to night imaging cameras. Despite years of development, high-sensitivity SWIR cameras are still expensive and not ready for large-volume production. Germanium (Ge) is a promising semiconductor to convert SWIR radiation and it has seen extensive development in conjunction with highspeed optical communications. We are demonstrating a new low-light level infrared array technology based on the single-photon sensitive Geiger avalanche PhotoDiode (Si-GPD) array technology developed at aPeak and low-dislocation Germanium processing developed at MIT. The core of the imaging camera is a Ge:Si photon-counting GPD pixel with CMOS readout. The primary technology objective is to demonstrate through prototyping and semiconductor process development the technical feasibility of single-photon detection cameras sensitive in the SWIR and set the performance specifications. We report on prototype Ge:Si structures compatible with the GPD operation and technology. We demonstrate >80% quantum efficiency at 1310nm and 45%-60% quantum efficiency at 1550nm. Dark current measurements indicate that single-photon sensitivity (2.6x10-18W/pixel) is achievable by cooling the detector at cryogenic temperatures down to 53K. A digital developed to provide adjustable dynamic range and frame rate is reported. Because the GPD detectors have intrinsic excellent gating and ranging capability, the pixel architecture is developed to enable the dual mode operation - passive illumination two-dimensional imaging (night vision) and active illumination three-dimensional imaging.

  9. Engineering design criteria for an image intensifier/image converter camera

    NASA Technical Reports Server (NTRS)

    Sharpsteen, J. T.; Lund, D. L.; Stoap, L. J.; Solheim, C. D.

    1976-01-01

    The design, display, and evaluation of an image intensifier/image converter camera which can be utilized in various requirements of spaceshuttle experiments are described. An image intensifier tube was utilized in combination with two brassboards as power supply and used for evaluation of night photography in the field. Pictures were obtained showing field details which would have been undistinguishable to the naked eye or to an ordinary camera.

  10. TIRCAM2: The TIFR near infrared imaging camera

    NASA Astrophysics Data System (ADS)

    Naik, M. B.; Ojha, D. K.; Ghosh, S. K.; Poojary, S. S.; Jadhav, R. B.; Meshram, G. S.; Sandimani, P. R.; Bhagat, S. B.; D'Costa, S. L. A.; Gharat, S. M.; Bakalkar, C. B.; Ninan, J. P.; Joshi, J. S.

    2012-12-01

    TIRCAM2 (TIFR near infrared imaging camera - II) is a closed cycle cooled imager that has been developed by the Infrared Astronomy Group at the Tata Institute of Fundamental Research for observations in the near infrared band of 1 to 3.7 μm with existing Indian telescopes. In this paper, we describe some of the technical details of TIRCAM2 and report its observing capabilities, measured performance and limiting magnitudes with the 2-m IUCAA Girawali telescope and the 1.2-m PRL Gurushikhar telescope. The main highlight is the camera's capability of observing in the nbL (3.59 mum) band enabling our primary motivation of mapping of Polycyclic Aromatic Hydrocarbon (PAH) emission at 3.3 mum.

  11. A Comparative Study of Microscopic Images Captured by a Box Type Digital Camera Versus a Standard Microscopic Photography Camera Unit

    PubMed Central

    Desai, Nandini J.; Gupta, B. D.; Patel, Pratik Narendrabhai

    2014-01-01

    Introduction: Obtaining images of slides viewed by a microscope can be invaluable for both diagnosis and teaching.They can be transferred among technologically-advanced hospitals for further consultation and evaluation. But a standard microscopic photography camera unit (MPCU)(MIPS-Microscopic Image projection System) is costly and not available in resource poor settings. The aim of our endeavour was to find a comparable and cheaper alternative method for photomicrography. Materials and Methods: We used a NIKON Coolpix S6150 camera (box type digital camera) with Olympus CH20i microscope and a fluorescent microscope for the purpose of this study. Results: We got comparable results for capturing images of light microscopy, but the results were not as satisfactory for fluorescent microscopy. Conclusion: A box type digital camera is a comparable, less expensive and convenient alternative to microscopic photography camera unit. PMID:25478350

  12. Camera system resolution and its influence on digital image correlation

    SciTech Connect

    Reu, Phillip L.; Sweatt, William; Miller, Timothy; Fleming, Darryn

    2014-09-21

    Digital image correlation (DIC) uses images from a camera and lens system to make quantitative measurements of the shape, displacement, and strain of test objects. This increasingly popular method has had little research on the influence of the imaging system resolution on the DIC results. This paper investigates the entire imaging system and studies how both the camera and lens resolution influence the DIC results as a function of the system Modulation Transfer Function (MTF). It will show that when making spatial resolution decisions (including speckle size) the resolution limiting component should be considered. A consequence of the loss of spatial resolution is that the DIC uncertainties will be increased. This is demonstrated using both synthetic and experimental images with varying resolution. The loss of image resolution and DIC accuracy can be compensated for by increasing the subset size, or better, by increasing the speckle size. The speckle-size and spatial resolution are now a function of the lens resolution rather than the more typical assumption of the pixel size. The study will demonstrate the tradeoffs associated with limited lens resolution.

  13. Camera system resolution and its influence on digital image correlation

    DOE PAGESBeta

    Reu, Phillip L.; Sweatt, William; Miller, Timothy; Fleming, Darryn

    2014-09-21

    Digital image correlation (DIC) uses images from a camera and lens system to make quantitative measurements of the shape, displacement, and strain of test objects. This increasingly popular method has had little research on the influence of the imaging system resolution on the DIC results. This paper investigates the entire imaging system and studies how both the camera and lens resolution influence the DIC results as a function of the system Modulation Transfer Function (MTF). It will show that when making spatial resolution decisions (including speckle size) the resolution limiting component should be considered. A consequence of the loss ofmore » spatial resolution is that the DIC uncertainties will be increased. This is demonstrated using both synthetic and experimental images with varying resolution. The loss of image resolution and DIC accuracy can be compensated for by increasing the subset size, or better, by increasing the speckle size. The speckle-size and spatial resolution are now a function of the lens resolution rather than the more typical assumption of the pixel size. The study will demonstrate the tradeoffs associated with limited lens resolution.« less

  14. A design of driving circuit for star sensor imaging camera

    NASA Astrophysics Data System (ADS)

    Li, Da-wei; Yang, Xiao-xu; Han, Jun-feng; Liu, Zhao-hui

    2016-01-01

    The star sensor is a high-precision attitude sensitive measuring instruments, which determine spacecraft attitude by detecting different positions on the celestial sphere. Imaging camera is an important portion of star sensor. The purpose of this study is to design a driving circuit based on Kodak CCD sensor. The design of driving circuit based on Kodak KAI-04022 is discussed, and the timing of this CCD sensor is analyzed. By the driving circuit testing laboratory and imaging experiments, it is found that the driving circuits can meet the requirements of Kodak CCD sensor.

  15. An efficient image compressor for charge coupled devices camera.

    PubMed

    Li, Jin; Xing, Fei; You, Zheng

    2014-01-01

    Recently, the discrete wavelet transforms- (DWT-) based compressor, such as JPEG2000 and CCSDS-IDC, is widely seen as the state of the art compression scheme for charge coupled devices (CCD) camera. However, CCD images project on the DWT basis to produce a large number of large amplitude high-frequency coefficients because these images have a large number of complex texture and contour information, which are disadvantage for the later coding. In this paper, we proposed a low-complexity posttransform coupled with compressing sensing (PT-CS) compression approach for remote sensing image. First, the DWT is applied to the remote sensing image. Then, a pair base posttransform is applied to the DWT coefficients. The pair base are DCT base and Hadamard base, which can be used on the high and low bit-rate, respectively. The best posttransform is selected by the l p -norm-based approach. The posttransform is considered as the sparse representation stage of CS. The posttransform coefficients are resampled by sensing measurement matrix. Experimental results on on-board CCD camera images show that the proposed approach significantly outperforms the CCSDS-IDC-based coder, and its performance is comparable to that of the JPEG2000 at low bit rate and it does not have the high excessive implementation complexity of JPEG2000. PMID:25114977

  16. An Efficient Image Compressor for Charge Coupled Devices Camera

    PubMed Central

    Li, Jin; Xing, Fei; You, Zheng

    2014-01-01

    Recently, the discrete wavelet transforms- (DWT-) based compressor, such as JPEG2000 and CCSDS-IDC, is widely seen as the state of the art compression scheme for charge coupled devices (CCD) camera. However, CCD images project on the DWT basis to produce a large number of large amplitude high-frequency coefficients because these images have a large number of complex texture and contour information, which are disadvantage for the later coding. In this paper, we proposed a low-complexity posttransform coupled with compressing sensing (PT-CS) compression approach for remote sensing image. First, the DWT is applied to the remote sensing image. Then, a pair base posttransform is applied to the DWT coefficients. The pair base are DCT base and Hadamard base, which can be used on the high and low bit-rate, respectively. The best posttransform is selected by the lp-norm-based approach. The posttransform is considered as the sparse representation stage of CS. The posttransform coefficients are resampled by sensing measurement matrix. Experimental results on on-board CCD camera images show that the proposed approach significantly outperforms the CCSDS-IDC-based coder, and its performance is comparable to that of the JPEG2000 at low bit rate and it does not have the high excessive implementation complexity of JPEG2000. PMID:25114977

  17. Goal-oriented rectification of camera-based document images.

    PubMed

    Stamatopoulos, Nikolaos; Gatos, Basilis; Pratikakis, Ioannis; Perantonis, Stavros J

    2011-04-01

    Document digitization with either flatbed scanners or camera-based systems results in document images which often suffer from warping and perspective distortions that deteriorate the performance of current OCR approaches. In this paper, we present a goal-oriented rectification methodology to compensate for undesirable document image distortions aiming to improve the OCR result. Our approach relies upon a coarse-to-fine strategy. First, a coarse rectification is accomplished with the aid of a computationally low cost transformation which addresses the projection of a curved surface to a 2-D rectangular area. The projection of the curved surface on the plane is guided only by the textual content's appearance in the document image while incorporating a transformation which does not depend on specific model primitives or camera setup parameters. Second, pose normalization is applied on the word level aiming to restore all the local distortions of the document image. Experimental results on various document images with a variety of distortions demonstrate the robustness and effectiveness of the proposed rectification methodology using a consistent evaluation methodology that encounters OCR accuracy and a newly introduced measure using a semi-automatic procedure. PMID:20876019

  18. Parallel phase-sensitive three-dimensional imaging camera

    DOEpatents

    Smithpeter, Colin L.; Hoover, Eddie R.; Pain, Bedabrata; Hancock, Bruce R.; Nellums, Robert O.

    2007-09-25

    An apparatus is disclosed for generating a three-dimensional (3-D) image of a scene illuminated by a pulsed light source (e.g. a laser or light-emitting diode). The apparatus, referred to as a phase-sensitive 3-D imaging camera utilizes a two-dimensional (2-D) array of photodetectors to receive light that is reflected or scattered from the scene and processes an electrical output signal from each photodetector in the 2-D array in parallel using multiple modulators, each having inputs of the photodetector output signal and a reference signal, with the reference signal provided to each modulator having a different phase delay. The output from each modulator is provided to a computational unit which can be used to generate intensity and range information for use in generating a 3-D image of the scene. The 3-D camera is capable of generating a 3-D image using a single pulse of light, or alternately can be used to generate subsequent 3-D images with each additional pulse of light.

  19. Quantifying biodiversity using digital cameras and automated image analysis.

    NASA Astrophysics Data System (ADS)

    Roadknight, C. M.; Rose, R. J.; Barber, M. L.; Price, M. C.; Marshall, I. W.

    2009-04-01

    Monitoring the effects on biodiversity of extensive grazing in complex semi-natural habitats is labour intensive. There are also concerns about the standardization of semi-quantitative data collection. We have chosen to focus initially on automating the most time consuming aspect - the image analysis. The advent of cheaper and more sophisticated digital camera technology has lead to a sudden increase in the number of habitat monitoring images and information that is being collected. We report on the use of automated trail cameras (designed for the game hunting market) to continuously capture images of grazer activity in a variety of habitats at Moor House National Nature Reserve, which is situated in the North of England at an average altitude of over 600m. Rainfall is high, and in most areas the soil consists of deep peat (1m to 3m), populated by a mix of heather, mosses and sedges. The cameras have been continuously in operation over a 6 month period, daylight images are in full colour and night images (IR flash) are black and white. We have developed artificial intelligence based methods to assist in the analysis of the large number of images collected, generating alert states for new or unusual image conditions. This paper describes the data collection techniques, outlines the quantitative and qualitative data collected and proposes online and offline systems that can reduce the manpower overheads and increase focus on important subsets in the collected data. By converting digital image data into statistical composite data it can be handled in a similar way to other biodiversity statistics thus improving the scalability of monitoring experiments. Unsupervised feature detection methods and supervised neural methods were tested and offered solutions to simplifying the process. Accurate (85 to 95%) categorization of faunal content can be obtained, requiring human intervention for only those images containing rare animals or unusual (undecidable) conditions, and

  20. CMOS image sensor noise reduction method for image signal processor in digital cameras and camera phones

    NASA Astrophysics Data System (ADS)

    Yoo, Youngjin; Lee, SeongDeok; Choe, Wonhee; Kim, Chang-Yong

    2007-02-01

    Digital images captured from CMOS image sensors suffer Gaussian noise and impulsive noise. To efficiently reduce the noise in Image Signal Processor (ISP), we analyze noise feature for imaging pipeline of ISP where noise reduction algorithm is performed. The Gaussian noise reduction and impulsive noise reduction method are proposed for proper ISP implementation in Bayer domain. The proposed method takes advantage of the analyzed noise feature to calculate noise reduction filter coefficients. Thus, noise is adaptively reduced according to the scene environment. Since noise is amplified and characteristic of noise varies while the image sensor signal undergoes several image processing steps, it is better to remove noise in earlier stage on imaging pipeline of ISP. Thus, noise reduction is carried out in Bayer domain on imaging pipeline of ISP. The method is tested on imaging pipeline of ISP and images captured from Samsung 2M CMOS image sensor test module. The experimental results show that the proposed method removes noise while effectively preserves edges.

  1. The role of camera-bundled image management software in the consumer digital imaging value chain

    NASA Astrophysics Data System (ADS)

    Mueller, Milton; Mundkur, Anuradha; Balasubramanian, Ashok; Chirania, Virat

    2005-02-01

    This research was undertaken by the Convergence Center at the Syracuse University School of Information Studies (www.digital-convergence.info). Project ICONICA, the name for the research, focuses on the strategic implications of digital Images and the CONvergence of Image management and image CApture. Consumer imaging - the activity that we once called "photography" - is now recognized as in the throes of a digital transformation. At the end of 2003, market researchers estimated that about 30% of the households in the U.S. and 40% of the households in Japan owned digital cameras. In 2004, of the 86 million new cameras sold (excluding one-time use cameras), a majority (56%) were estimated to be digital cameras. Sales of photographic film, while still profitable, are declining precipitously.

  2. Multiwavelength adaptive optical fundus camera and continuous retinal imaging

    NASA Astrophysics Data System (ADS)

    Yang, Han-sheng; Li, Min; Dai, Yun; Zhang, Yu-dong

    2009-08-01

    We have constructed a new version of retinal imaging system with chromatic aberration concerned and the correlated optical design presented in this article is based on the adaptive optics fundus camera modality. In our system, three typical wavelengths of 550nm, 650nm and 480nm were selected. Longitude chromatic aberration (LCA) was traded off to a minimum using ZEMAX program. The whole setup was actually evaluated on human subjects and retinal imaging was performed at continuous frame rates up to 20 Hz. Raw videos at parafovea locations were collected, and cone mosaics as well as retinal vasculature were clearly observed in one single clip. In addition, comparisons under different illumination conditions were also made to confirm our design. Image contrast and the Strehl ratio were effectively increased after dynamic correction of high order aberrations. This system is expected to bring new applications in functional imaging of human retina.

  3. Imaging of Venus from Galileo: Early results and camera performance

    USGS Publications Warehouse

    Belton, M.J.S.; Gierasch, P.; Klaasen, K.P.; Anger, C.D.; Carr, M.H.; Chapman, C.R.; Davies, M.E.; Greeley, R.; Greenberg, R.; Head, J.W.; Neukum, G.; Pilcher, C.B.; Veverka, J.; Fanale, F.P.; Ingersoll, A.P.; Pollock, J.B.; Morrison, D.; Clary, M.C.; Cunningham, W.; Breneman, H.

    1992-01-01

    Three images of Venus have been returned so far by the Galileo spacecraft following an encounter with the planet on UT February 10, 1990. The images, taken at effective wavelengths of 4200 and 9900 A??, characterize the global motions and distribution of haze near the Venus cloud tops and, at the latter wavelength, deep within the main cloud. Previously undetected markings are clearly seen in the near-infrared image. The global distribution of these features, which have maximum contrasts of 3%, is different from that recorded at short wavelengths. In particular, the "polar collar," which is omnipresent in short wavelength images, is absent at 9900 A??. The maximum contrast in the features at 4200 A?? is about 20%. The optical performance of the camera is described and is judged to be nominal. ?? 1992.

  4. Comparison of Kodak Professional Digital Camera System images to conventional film, still video, and freeze-frame images

    NASA Astrophysics Data System (ADS)

    Kent, Richard A.; McGlone, John T.; Zoltowski, Norbert W.

    1991-06-01

    Electronic cameras provide near real time image evaluation with the benefits of digital storage methods for rapid transmission or computer processing and enhancement of images. But how does the image quality of their images compare to that of conventional film? A standard Nikon F-3TM 35 mm SLR camera was transformed into an electro-optical camera by replacing the film back with Kodak's KAF-1400V (or KAF-1300L) megapixel CCD array detector back and a processing accessory. Images taken with these Kodak electronic cameras were compared to those using conventional films and to several still video cameras. Quantitative and qualitative methods were used to compare images from these camera systems. Images captured on conventional video analog systems provide a maximum of 450 - 500 TV lines of resolution depending upon the camera resolution, storage method, and viewing system resolution. The Kodak Professional Digital Camera SystemTM exceeded this resolution and more closely approached that of film.

  5. Photon-efficient imaging with a single-photon camera

    NASA Astrophysics Data System (ADS)

    Shin, Dongeek; Xu, Feihu; Venkatraman, Dheera; Lussana, Rudi; Villa, Federica; Zappa, Franco; Goyal, Vivek K.; Wong, Franco N. C.; Shapiro, Jeffrey H.

    2016-06-01

    Reconstructing a scene's 3D structure and reflectivity accurately with an active imaging system operating in low-light-level conditions has wide-ranging applications, spanning biological imaging to remote sensing. Here we propose and experimentally demonstrate a depth and reflectivity imaging system with a single-photon camera that generates high-quality images from ~1 detected signal photon per pixel. Previous achievements of similar photon efficiency have been with conventional raster-scanning data collection using single-pixel photon counters capable of ~10-ps time tagging. In contrast, our camera's detector array requires highly parallelized time-to-digital conversions with photon time-tagging accuracy limited to ~ns. Thus, we develop an array-specific algorithm that converts coarsely time-binned photon detections to highly accurate scene depth and reflectivity by exploiting both the transverse smoothness and longitudinal sparsity of natural scenes. By overcoming the coarse time resolution of the array, our framework uniquely achieves high photon efficiency in a relatively short acquisition time.

  6. Photon-efficient imaging with a single-photon camera

    PubMed Central

    Shin, Dongeek; Xu, Feihu; Venkatraman, Dheera; Lussana, Rudi; Villa, Federica; Zappa, Franco; Goyal, Vivek K.; Wong, Franco N. C.; Shapiro, Jeffrey H.

    2016-01-01

    Reconstructing a scene's 3D structure and reflectivity accurately with an active imaging system operating in low-light-level conditions has wide-ranging applications, spanning biological imaging to remote sensing. Here we propose and experimentally demonstrate a depth and reflectivity imaging system with a single-photon camera that generates high-quality images from ∼1 detected signal photon per pixel. Previous achievements of similar photon efficiency have been with conventional raster-scanning data collection using single-pixel photon counters capable of ∼10-ps time tagging. In contrast, our camera's detector array requires highly parallelized time-to-digital conversions with photon time-tagging accuracy limited to ∼ns. Thus, we develop an array-specific algorithm that converts coarsely time-binned photon detections to highly accurate scene depth and reflectivity by exploiting both the transverse smoothness and longitudinal sparsity of natural scenes. By overcoming the coarse time resolution of the array, our framework uniquely achieves high photon efficiency in a relatively short acquisition time. PMID:27338821

  7. Photon-efficient imaging with a single-photon camera.

    PubMed

    Shin, Dongeek; Xu, Feihu; Venkatraman, Dheera; Lussana, Rudi; Villa, Federica; Zappa, Franco; Goyal, Vivek K; Wong, Franco N C; Shapiro, Jeffrey H

    2016-01-01

    Reconstructing a scene's 3D structure and reflectivity accurately with an active imaging system operating in low-light-level conditions has wide-ranging applications, spanning biological imaging to remote sensing. Here we propose and experimentally demonstrate a depth and reflectivity imaging system with a single-photon camera that generates high-quality images from ∼1 detected signal photon per pixel. Previous achievements of similar photon efficiency have been with conventional raster-scanning data collection using single-pixel photon counters capable of ∼10-ps time tagging. In contrast, our camera's detector array requires highly parallelized time-to-digital conversions with photon time-tagging accuracy limited to ∼ns. Thus, we develop an array-specific algorithm that converts coarsely time-binned photon detections to highly accurate scene depth and reflectivity by exploiting both the transverse smoothness and longitudinal sparsity of natural scenes. By overcoming the coarse time resolution of the array, our framework uniquely achieves high photon efficiency in a relatively short acquisition time. PMID:27338821

  8. A two-camera imaging system for pest detection and aerial application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation reports on the design and testing of an airborne two-camera imaging system for pest detection and aerial application assessment. The system consists of two digital cameras with 5616 x 3744 effective pixels. One camera captures normal color images with blue, green and red bands, whi...

  9. Single-quantum dot imaging with a photon counting camera

    PubMed Central

    Michalet, X.; Colyer, R. A.; Antelman, J.; Siegmund, O.H.W.; Tremsin, A.; Vallerga, J.V.; Weiss, S.

    2010-01-01

    The expanding spectrum of applications of single-molecule fluorescence imaging ranges from fundamental in vitro studies of biomolecular activity to tracking of receptors in live cells. The success of these assays has relied on progresses in organic and non-organic fluorescent probe developments as well as improvements in the sensitivity of light detectors. We describe a new type of detector developed with the specific goal of ultra-sensitive single-molecule imaging. It is a wide-field, photon-counting detector providing high temporal and high spatial resolution information for each incoming photon. It can be used as a standard low-light level camera, but also allows access to a lot more information, such as fluorescence lifetime and spatio-temporal correlations. We illustrate the single-molecule imaging performance of our current prototype using quantum dots and discuss on-going and future developments of this detector. PMID:19689323

  10. Parallel image compression circuit for high-speed cameras

    NASA Astrophysics Data System (ADS)

    Nishikawa, Yukinari; Kawahito, Shoji; Inoue, Toru

    2005-02-01

    In this paper, we propose 32 parallel image compression circuits for high-speed cameras. The proposed compression circuits are based on a 4 x 4-point 2-dimensional DCT using a DA method, zigzag scanning of 4 blocks of the 2-D DCT coefficients and a 1-dimensional Huffman coding. The compression engine is designed with FPGAs, and the hardware complexity is compared with JPEG algorithm. It is found that the proposed compression circuits require much less hardware, leading to a compact high-speed implementation of the image compression circuits using parallel processing architecture. The PSNR of the reconstructed image using the proposed encoding method is better than that of JPEG at the region of low compression ratio.

  11. Frequency Identification of Vibration Signals Using Video Camera Image Data

    PubMed Central

    Jeng, Yih-Nen; Wu, Chia-Hung

    2012-01-01

    This study showed that an image data acquisition system connecting a high-speed camera or webcam to a notebook or personal computer (PC) can precisely capture most dominant modes of vibration signal, but may involve the non-physical modes induced by the insufficient frame rates. Using a simple model, frequencies of these modes are properly predicted and excluded. Two experimental designs, which involve using an LED light source and a vibration exciter, are proposed to demonstrate the performance. First, the original gray-level resolution of a video camera from, for instance, 0 to 256 levels, was enhanced by summing gray-level data of all pixels in a small region around the point of interest. The image signal was further enhanced by attaching a white paper sheet marked with a black line on the surface of the vibration system in operation to increase the gray-level resolution. Experimental results showed that the Prosilica CV640C CMOS high-speed camera has the critical frequency of inducing the false mode at 60 Hz, whereas that of the webcam is 7.8 Hz. Several factors were proven to have the effect of partially suppressing the non-physical modes, but they cannot eliminate them completely. Two examples, the prominent vibration modes of which are less than the associated critical frequencies, are examined to demonstrate the performances of the proposed systems. In general, the experimental data show that the non-contact type image data acquisition systems are potential tools for collecting the low-frequency vibration signal of a system. PMID:23202026

  12. Frequency identification of vibration signals using video camera image data.

    PubMed

    Jeng, Yih-Nen; Wu, Chia-Hung

    2012-01-01

    This study showed that an image data acquisition system connecting a high-speed camera or webcam to a notebook or personal computer (PC) can precisely capture most dominant modes of vibration signal, but may involve the non-physical modes induced by the insufficient frame rates. Using a simple model, frequencies of these modes are properly predicted and excluded. Two experimental designs, which involve using an LED light source and a vibration exciter, are proposed to demonstrate the performance. First, the original gray-level resolution of a video camera from, for instance, 0 to 256 levels, was enhanced by summing gray-level data of all pixels in a small region around the point of interest. The image signal was further enhanced by attaching a white paper sheet marked with a black line on the surface of the vibration system in operation to increase the gray-level resolution. Experimental results showed that the Prosilica CV640C CMOS high-speed camera has the critical frequency of inducing the false mode at 60 Hz, whereas that of the webcam is 7.8 Hz. Several factors were proven to have the effect of partially suppressing the non-physical modes, but they cannot eliminate them completely. Two examples, the prominent vibration modes of which are less than the associated critical frequencies, are examined to demonstrate the performances of the proposed systems. In general, the experimental data show that the non-contact type image data acquisition systems are potential tools for collecting the low-frequency vibration signal of a system. PMID:23202026

  13. On image sensor dynamic range utilized by security cameras

    NASA Astrophysics Data System (ADS)

    Johannesson, Anders

    2012-03-01

    The dynamic range is an important quantity used to describe an image sensor. Wide/High/Extended dynamic range is often brought forward as an important feature to compare one device to another. The dynamic range of an image sensor is normally given as a single number, which is often insufficient since a single number will not fully describe the dynamic capabilities of the sensor. A camera is ideally based on a sensor that can cope with the dynamic range of the scene. Otherwise it has to sacrifice some part of the available data. For a security camera the latter may be critical since important objects might be hidden in the sacrificed part of the scene. In this paper we compare the dynamic capabilities of some image sensors utilizing a visual tool. The comparison is based on the use case, common in surveillance, where low contrast objects may appear in any part of a scene that through its uneven illumination, span a high dynamic range. The investigation is based on real sensor data that has been measured in our lab and a synthetic test scene is used to mimic the low contrast objects. With this technique it is possible to compare sensors with different intrinsic dynamic properties as well as some capture techniques used to create an effect of increased dynamic range.

  14. Estimation of Cometary Rotation Parameters Based on Camera Images

    NASA Technical Reports Server (NTRS)

    Spindler, Karlheinz

    2007-01-01

    The purpose of the Rosetta mission is the in situ analysis of a cometary nucleus using both remote sensing equipment and scientific instruments delivered to the comet surface by a lander and transmitting measurement data to the comet-orbiting probe. Following a tour of planets including one Mars swing-by and three Earth swing-bys, the Rosetta probe is scheduled to rendezvous with comet 67P/Churyumov-Gerasimenko in May 2014. The mission poses various flight dynamics challenges, both in terms of parameter estimation and maneuver planning. Along with spacecraft parameters, the comet's position, velocity, attitude, angular velocity, inertia tensor and gravitatonal field need to be estimated. The measurements on which the estimation process is based are ground-based measurements (range and Doppler) yielding information on the heliocentric spacecraft state and images taken by an on-board camera yielding informaton on the comet state relative to the spacecraft. The image-based navigation depends on te identification of cometary landmarks (whose body coordinates also need to be estimated in the process). The paper will describe the estimation process involved, focusing on the phase when, after orbit insertion, the task arises to estimate the cometary rotational motion from camera images on which individual landmarks begin to become identifiable.

  15. Noise evaluation of Compton camera imaging for proton therapy.

    PubMed

    Ortega, P G; Torres-Espallardo, I; Cerutti, F; Ferrari, A; Gillam, J E; Lacasta, C; Llosá, G; Oliver, J F; Sala, P R; Solevi, P; Rafecas, M

    2015-03-01

    Compton Cameras emerged as an alternative for real-time dose monitoring techniques for Particle Therapy (PT), based on the detection of prompt-gammas. As a consequence of the Compton scattering process, the gamma origin point can be restricted onto the surface of a cone (Compton cone). Through image reconstruction techniques, the distribution of the gamma emitters can be estimated, using cone-surfaces backprojections of the Compton cones through the image space, along with more sophisticated statistical methods to improve the image quality. To calculate the Compton cone required for image reconstruction, either two interactions, the last being photoelectric absorption, or three scatter interactions are needed. Because of the high energy of the photons in PT the first option might not be adequate, as the photon is not absorbed in general. However, the second option is less efficient. That is the reason to resort to spectral reconstructions, where the incoming γ energy is considered as a variable in the reconstruction inverse problem. Jointly with prompt gamma, secondary neutrons and scattered photons, not strongly correlated with the dose map, can also reach the imaging detector and produce false events. These events deteriorate the image quality. Also, high intensity beams can produce particle accumulation in the camera, which lead to an increase of random coincidences, meaning events which gather measurements from different incoming particles. The noise scenario is expected to be different if double or triple events are used, and consequently, the reconstructed images can be affected differently by spurious data. The aim of the present work is to study the effect of false events in the reconstructed image, evaluating their impact in the determination of the beam particle ranges. A simulation study that includes misidentified events (neutrons and random coincidences) in the final image of a Compton Telescope for PT monitoring is presented. The complete chain of

  16. Noise evaluation of Compton camera imaging for proton therapy

    NASA Astrophysics Data System (ADS)

    Ortega, P. G.; Torres-Espallardo, I.; Cerutti, F.; Ferrari, A.; Gillam, J. E.; Lacasta, C.; Llosá, G.; Oliver, J. F.; Sala, P. R.; Solevi, P.; Rafecas, M.

    2015-02-01

    Compton Cameras emerged as an alternative for real-time dose monitoring techniques for Particle Therapy (PT), based on the detection of prompt-gammas. As a consequence of the Compton scattering process, the gamma origin point can be restricted onto the surface of a cone (Compton cone). Through image reconstruction techniques, the distribution of the gamma emitters can be estimated, using cone-surfaces backprojections of the Compton cones through the image space, along with more sophisticated statistical methods to improve the image quality. To calculate the Compton cone required for image reconstruction, either two interactions, the last being photoelectric absorption, or three scatter interactions are needed. Because of the high energy of the photons in PT the first option might not be adequate, as the photon is not absorbed in general. However, the second option is less efficient. That is the reason to resort to spectral reconstructions, where the incoming γ energy is considered as a variable in the reconstruction inverse problem. Jointly with prompt gamma, secondary neutrons and scattered photons, not strongly correlated with the dose map, can also reach the imaging detector and produce false events. These events deteriorate the image quality. Also, high intensity beams can produce particle accumulation in the camera, which lead to an increase of random coincidences, meaning events which gather measurements from different incoming particles. The noise scenario is expected to be different if double or triple events are used, and consequently, the reconstructed images can be affected differently by spurious data. The aim of the present work is to study the effect of false events in the reconstructed image, evaluating their impact in the determination of the beam particle ranges. A simulation study that includes misidentified events (neutrons and random coincidences) in the final image of a Compton Telescope for PT monitoring is presented. The complete chain of

  17. “Calibration-on-the-spot”: How to calibrate an EMCCD camera from its images

    PubMed Central

    Mortensen, Kim I.; Flyvbjerg, Henrik

    2016-01-01

    In order to count photons with a camera, the camera must be calibrated. Photon counting is necessary, e.g., to determine the precision of localization-based super-resolution microscopy. Here we present a protocol that calibrates an EMCCD camera from information contained in isolated, diffraction-limited spots in any image taken by the camera, thus making dedicated calibration procedures redundant by enabling calibration post festum, from images filed without calibration information. PMID:27381055

  18. “Calibration-on-the-spot”: How to calibrate an EMCCD camera from its images

    NASA Astrophysics Data System (ADS)

    Mortensen, Kim I.; Flyvbjerg, Henrik

    2016-07-01

    In order to count photons with a camera, the camera must be calibrated. Photon counting is necessary, e.g., to determine the precision of localization-based super-resolution microscopy. Here we present a protocol that calibrates an EMCCD camera from information contained in isolated, diffraction-limited spots in any image taken by the camera, thus making dedicated calibration procedures redundant by enabling calibration post festum, from images filed without calibration information.

  19. LROC WAC 100 Meter Scale Photometrically Normalized Map of the Moon

    NASA Astrophysics Data System (ADS)

    Boyd, A. K.; Nuno, R. G.; Robinson, M. S.; Denevi, B. W.; Hapke, B. W.

    2013-12-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) monthly global observations allowed derivation of a robust empirical photometric solution over a broad range of incidence, emission and phase (i, e, g) angles. Combining the WAC stereo-based GLD100 [1] digital terrain model (DTM) and LOLA polar DTMs [2] enabled precise topographic corrections to photometric angles. Over 100,000 WAC observations at 643 nm were calibrated to reflectance (I/F). Photometric angles (i, e, g), latitude, and longitude were calculated and stored for each WAC pixel. The 6-dimensional data set was then reduced to 3 dimensions by photometrically normalizing I/F with a global solution similar to [3]. The global solution was calculated from three 2°x2° tiles centered on (1°N, 147°E), (45°N, 147°E), and (89°N, 147°E), and included over 40 million WAC pixels. A least squares fit to a multivariate polynomial of degree 4 (f(i,e,g)) was performed, and the result was the starting point for a minimum search solving the non-linear function min[{1-[ I/F / f(i,e,g)] }2]. The input pixels were filtered to incidence angles (calculated from topography) < 89° and I/F greater than a minimum threshold to avoid shadowed pixels, and the output normalized I/F values were gridded into an equal-area map projection at 100 meters/pixel. At each grid location the median, standard deviation, and count of valid pixels were recorded. The normalized reflectance map is the result of the median of all normalized WAC pixels overlapping that specific 100-m grid cell. There are an average of 86 WAC normalized I/F estimates at each cell [3]. The resulting photometrically normalized mosaic provides the means to accurately compare I/F values for different regions on the Moon (see Nuno et al. [4]). The subtle differences in normalized I/F can now be traced across the local topography at regions that are illuminated at any point during the LRO mission (while the WAC was imaging), including at polar

  20. Ceres Survey Atlas derived from Dawn Framing Camera images

    NASA Astrophysics Data System (ADS)

    Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

    2016-02-01

    The Dawn Framing Camera (FC) acquired almost 900 clear filter images of Ceres with a resolution of about 400 m/pixels during the seven cycles in the Survey orbit in June 2015. We ortho-rectified 42 images from the third cycle and produced a global, high-resolution, controlled mosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 3 tiles mapped at a scale of 1:2,000,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The whole atlas is available to the public through the Dawn GIS web page.

  1. Real-time viewpoint image synthesis using strips of multi-camera images

    NASA Astrophysics Data System (ADS)

    Date, Munekazu; Takada, Hideaki; Kojima, Akira

    2015-03-01

    A real-time viewpoint image generation method is achieved. Video communications with a high sense of reality are needed to make natural connections between users at different places. One of the key technologies to achieve a sense of high reality is image generation corresponding to an individual user's viewpoint. However, generating viewpoint images requires advanced image processing, which is usually too heavy to use for real-time and low-latency purposes. In this paper we propose a real-time viewpoint image generation method using simple blending of multiple camera images taken at equal horizontal intervals and convergence obtained by using approximate information of an object's depth. An image generated from the nearest camera images is visually perceived as an intermediate viewpoint image due to the visual effect of depth-fused 3D (DFD). If the viewpoint is not on the line of the camera array, a viewpoint image could be generated by region splitting. We made a prototype viewpoint image generation system and achieved real-time full-frame operation for stereo HD videos. The users can see their individual viewpoint image for left-and-right and back-and-forth movement toward the screen. Our algorithm is very simple and promising as a means for achieving video communication with high reality.

  2. Embedded image enhancement for high-throughput cameras

    NASA Astrophysics Data System (ADS)

    Geerts, Stan J. C.; Cornelissen, Dion; de With, Peter H. N.

    2014-03-01

    This paper presents image enhancement for a novel Ultra-High-Definition (UHD) video camera offering 4K images and higher. Conventional image enhancement techniques need to be reconsidered for the high-resolution images and the low-light sensitivity of the new sensor. We study two image enhancement functions and evaluate and optimize the algorithms for embedded implementation in programmable logic (FPGA). The enhancement study involves high-quality Auto White Balancing (AWB) and Local Contrast Enhancement (LCE). We have compared multiple algorithms from literature, both with objective and subjective metrics. In order to objectively compare Local Contrast (LC), an existing LC metric is modified for LC measurement in UHD images. For AWB, we have found that color histogram stretching offers a subjective high image quality and it is among the algorithms with the lowest complexity, while giving only a small balancing error. We impose a color-to-color gain constraint, which improves robustness of low-light images. For local contrast enhancement, a combination of contrast preserving gamma and single-scale Retinex is selected. A modified bilateral filter is designed to prevent halo artifacts, while significantly reducing the complexity and simultaneously preserving quality. We show that by cascading contrast preserving gamma and single-scale Retinex, the visibility of details is improved towards the level appropriate for high-quality surveillance applications. The user is offered control over the amount of enhancement. Also, we discuss the mapping of those functions on a heterogeneous platform to come to an effective implementation while preserving quality and robustness.

  3. A comparison of select image-compression algorithms for an electronic still camera

    NASA Technical Reports Server (NTRS)

    Nerheim, Rosalee

    1989-01-01

    This effort is a study of image-compression algorithms for an electronic still camera. An electronic still camera can record and transmit high-quality images without the use of film, because images are stored digitally in computer memory. However, high-resolution images contain an enormous amount of information, and will strain the camera's data-storage system. Image compression will allow more images to be stored in the camera's memory. For the electronic still camera, a compression algorithm that produces a reconstructed image of high fidelity is most important. Efficiency of the algorithm is the second priority. High fidelity and efficiency are more important than a high compression ratio. Several algorithms were chosen for this study and judged on fidelity, efficiency and compression ratio. The transform method appears to be the best choice. At present, the method is compressing images to a ratio of 5.3:1 and producing high-fidelity reconstructed images.

  4. Inflight Calibration of the Lunar Reconnaissance Orbiter Camera Wide Angle Camera

    NASA Astrophysics Data System (ADS)

    Mahanti, P.; Humm, D. C.; Robinson, M. S.; Boyd, A. K.; Stelling, R.; Sato, H.; Denevi, B. W.; Braden, S. E.; Bowman-Cisneros, E.; Brylow, S. M.; Tschimmel, M.

    2016-04-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) has acquired more than 250,000 images of the illuminated lunar surface and over 190,000 observations of space and non-illuminated Moon since 1 January 2010. These images, along with images from the Narrow Angle Camera (NAC) and other Lunar Reconnaissance Orbiter instrument datasets are enabling new discoveries about the morphology, composition, and geologic/geochemical evolution of the Moon. Characterizing the inflight WAC system performance is crucial to scientific and exploration results. Pre-launch calibration of the WAC provided a baseline characterization that was critical for early targeting and analysis. Here we present an analysis of WAC performance from the inflight data. In the course of our analysis we compare and contrast with the pre-launch performance wherever possible and quantify the uncertainty related to various components of the calibration process. We document the absolute and relative radiometric calibration, point spread function, and scattered light sources and provide estimates of sources of uncertainty for spectral reflectance measurements of the Moon across a range of imaging conditions.

  5. Image deblurring using the direction dependence of camera resolution

    NASA Astrophysics Data System (ADS)

    Hirai, Yukio; Yoshikawa, Hiroyasu; Shimizu, Masayoshi

    2013-03-01

    The blurring that occurs in the lens of a camera has a tendency to further degrade in areas away from the on-axis of the image. In addition, the degradation of the blurred image in an off-axis area exhibits directional dependence. Conventional methods have been known to use the Wiener filter or the Richardson-Lucy algorithm to mitigate the problem. These methods use the pre-defined point spread function (PSF) in the restoration process, thereby preventing an increase in the noise elements. However, the nonuniform degradation that depends on the direction is not improved even though the edges are emphasized by these conventional methods. In this paper, we analyze the directional dependence of resolution based on the modeling of an optical system using a blurred image. We propose a novel image deblurring method that employs a reverse filter based on optimizing the directional dependence coefficients of the regularization term in the maximum a posterior probability (MAP) algorithm. We have improved the directional dependence of resolution by optimizing the weight coefficients of the direction in which the resolution is degraded.

  6. Color binarization for complex camera-based images

    NASA Astrophysics Data System (ADS)

    Thillou, C.‰line; Gosselin, Bernard

    2005-01-01

    This paper describes a new automatic color thresholding based on wavelet denoising and color clustering with K-means in order to segment text information in a camera-based image. Several parameters bring different information and this paper tries to explain how to use this complementarity. It is mainly based on the discrimination between two kinds of backgrounds: clean or complex. On one hand, this separation is useful to apply a particular algorithm on each of these cases and on the other hand to decrease the computation time for clean cases for which a faster method could be considered. Finally, several experiments were done to discuss results and to conclude that the use of a discrimination between kinds of backgrounds gives better results in terms of Precision and Recall.

  7. Color binarization for complex camera-based images

    NASA Astrophysics Data System (ADS)

    Thillou, Céline; Gosselin, Bernard

    2004-12-01

    This paper describes a new automatic color thresholding based on wavelet denoising and color clustering with K-means in order to segment text information in a camera-based image. Several parameters bring different information and this paper tries to explain how to use this complementarity. It is mainly based on the discrimination between two kinds of backgrounds: clean or complex. On one hand, this separation is useful to apply a particular algorithm on each of these cases and on the other hand to decrease the computation time for clean cases for which a faster method could be considered. Finally, several experiments were done to discuss results and to conclude that the use of a discrimination between kinds of backgrounds gives better results in terms of Precision and Recall.

  8. Color calibration of a CMOS digital camera for mobile imaging

    NASA Astrophysics Data System (ADS)

    Eliasson, Henrik

    2010-01-01

    As white balance algorithms employed in mobile phone cameras become increasingly sophisticated by using, e.g., elaborate white-point estimation methods, a proper color calibration is necessary. Without such a calibration, the estimation of the light source for a given situation may go wrong, giving rise to large color errors. At the same time, the demands for efficiency in the production environment require the calibration to be as simple as possible. Thus it is important to find the correct balance between image quality and production efficiency requirements. The purpose of this work is to investigate camera color variations using a simple model where the sensor and IR filter are specified in detail. As input to the model, spectral data of the 24-color Macbeth Colorchecker was used. This data was combined with the spectral irradiance of mainly three different light sources: CIE A, D65 and F11. The sensor variations were determined from a very large population from which 6 corner samples were picked out for further analysis. Furthermore, a set of 100 IR filters were picked out and measured. The resulting images generated by the model were then analyzed in the CIELAB space and color errors were calculated using the ΔE94 metric. The results of the analysis show that the maximum deviations from the typical values are small enough to suggest that a white balance calibration is sufficient. Furthermore, it is also demonstrated that the color temperature dependence is small enough to justify the use of only one light source in a production environment.

  9. Arthropod eye-inspired digital camera with unique imaging characteristics

    NASA Astrophysics Data System (ADS)

    Xiao, Jianliang; Song, Young Min; Xie, Yizhu; Malyarchuk, Viktor; Jung, Inhwa; Choi, Ki-Joong; Liu, Zhuangjian; Park, Hyunsung; Lu, Chaofeng; Kim, Rak-Hwan; Li, Rui; Crozier, Kenneth B.; Huang, Yonggang; Rogers, John A.

    2014-06-01

    In nature, arthropods have a remarkably sophisticated class of imaging systems, with a hemispherical geometry, a wideangle field of view, low aberrations, high acuity to motion and an infinite depth of field. There are great interests in building systems with similar geometries and properties due to numerous potential applications. However, the established semiconductor sensor technologies and optics are essentially planar, which experience great challenges in building such systems with hemispherical, compound apposition layouts. With the recent advancement of stretchable optoelectronics, we have successfully developed strategies to build a fully functional artificial apposition compound eye camera by combining optics, materials and mechanics principles. The strategies start with fabricating stretchable arrays of thin silicon photodetectors and elastomeric optical elements in planar geometries, which are then precisely aligned and integrated, and elastically transformed to hemispherical shapes. This imaging device demonstrates nearly full hemispherical shape (about 160 degrees), with densely packed artificial ommatidia. The number of ommatidia (180) is comparable to those of the eyes of fire ants and bark beetles. We have illustrated key features of operation of compound eyes through experimental imaging results and quantitative ray-tracing-based simulations. The general strategies shown in this development could be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes).

  10. Solid state television camera has no imaging tube

    NASA Technical Reports Server (NTRS)

    Huggins, C. T.

    1972-01-01

    Camera with characteristics of vidicon camera and greater resolution than home TV receiver uses mosaic of phototransistors. Because of low power and small size, camera has many applications. Mosaics can be used as cathode ray tubes and analog-to-digital converters.

  11. Coded-aperture Compton camera for gamma-ray imaging

    NASA Astrophysics Data System (ADS)

    Farber, Aaron M.

    This dissertation describes the development of a novel gamma-ray imaging system concept and presents results from Monte Carlo simulations of the new design. Current designs for large field-of-view gamma cameras suitable for homeland security applications implement either a coded aperture or a Compton scattering geometry to image a gamma-ray source. Both of these systems require large, expensive position-sensitive detectors in order to work effectively. By combining characteristics of both of these systems, a new design can be implemented that does not require such expensive detectors and that can be scaled down to a portable size. This new system has significant promise in homeland security, astronomy, botany and other fields, while future iterations may prove useful in medical imaging, other biological sciences and other areas, such as non-destructive testing. A proof-of-principle study of the new gamma-ray imaging system has been performed by Monte Carlo simulation. Various reconstruction methods have been explored and compared. General-Purpose Graphics-Processor-Unit (GPGPU) computation has also been incorporated. The resulting code is a primary design tool for exploring variables such as detector spacing, material selection and thickness and pixel geometry. The advancement of the system from a simple 1-dimensional simulation to a full 3-dimensional model is described. Methods of image reconstruction are discussed and results of simulations consisting of both a 4 x 4 and a 16 x 16 object space mesh have been presented. A discussion of the limitations and potential areas of further study is also presented.

  12. Electron detection characteristics of a slow-scan CCD camera, imaging plates and film, and electron image restoration.

    PubMed

    Zuo, J M

    2000-05-01

    Electron detection characteristics are summarized for the slow scan CCD (SSC) camera, imaging plates, and film. The advantage of each detector is demonstrated with the selected examples of electron diffraction and imaging. The Richardson-Lucy algorithm for image restoration is described and tested for images recorded with the SSC camera. The effectiveness of image restoration is demonstrated for the recorded high-resolution lattice image, energy-loss spectrum, and convergent beam electron diffraction (CBED) pattern. PMID:10816266

  13. The Hayabusa Spacecraft Asteroid Multi-band Imaging Camera (AMICA)

    NASA Astrophysics Data System (ADS)

    Ishiguro, Masateru; Nakamura, Ryosuke; Tholen, David J.; Hirata, Naru; Demura, Hirohide; Nemoto, Etsuko; Nakamura, Akiko M.; Higuchi, Yuta; Sogame, Akito; Yamamoto, Aya; Kitazato, Kohei; Yokota, Yasuhiro; Kubota, Takashi; Hashimoto, Tatsuaki; Saito, Jun

    2010-06-01

    The Hayabusa Spacecraft Asteroid Multi-band Imaging Camera (AMICA) has acquired more than 1400 multispectral and high-resolution images of its target asteroid, 25143 Itokawa, since late August 2005. In this paper, we summarize the design and performance of AMICA. In addition, we describe the calibration methods, assumptions, and models, based on measurements. Major calibration steps include corrections for linearity and modeling and subtraction of bias, dark current, read-out smear, and pixel-to-pixel responsivity variations. AMICA v-band data were calibrated to radiance using in-flight stellar observations. The other band data were calibrated to reflectance by comparing them to ground-based observations to avoid the uncertainty of the solar irradiation in those bands. We found that the AMICA signal was linear with respect to the input signal to an accuracy of ≪1% when the signal level was <3800 DN. We verified that the absolute radiance calibration of the AMICA v-band (0.55 μm) was accurate to 4% or less, the accuracy of the disk-integrated spectra with respect to the AMICA v-band was about 1%, and the pixel-to-pixel responsivity (flat-field) variation was 3% or less. The uncertainty in background zero level was 5 DN. From wide-band observations of star clusters, we found that the AMICA optics have an effective focal length of 120.80 ± 0.03 mm, yielding a field-of-view (FOV) of 5.83° × 5.69°. The resulting geometric distortion model was accurate to within a third of a pixel. We demonstrated an image-restoration technique using the point-spread functions of stars, and confirmed that the technique functions well in all loss-less images. An artifact not corrected by this calibration is scattered light associated with bright disks in the FOV.

  14. Extreme ultra-violet movie camera for imaging microsecond time scale magnetic reconnection

    SciTech Connect

    Chai, Kil-Byoung; Bellan, Paul M.

    2013-12-15

    An ultra-fast extreme ultra-violet (EUV) movie camera has been developed for imaging magnetic reconnection in the Caltech spheromak/astrophysical jet experiment. The camera consists of a broadband Mo:Si multilayer mirror, a fast decaying YAG:Ce scintillator, a visible light block, and a high-speed visible light CCD camera. The camera can capture EUV images as fast as 3.3 × 10{sup 6} frames per second with 0.5 cm spatial resolution. The spectral range is from 20 eV to 60 eV. EUV images reveal strong, transient, highly localized bursts of EUV radiation when magnetic reconnection occurs.

  15. Rotating prism design for continuous image compensation cameras.

    PubMed

    Waddell, J H

    1966-07-01

    The rotating prisms used in high-speed motion-picture cameras have been designed empirically since their first use thirty-two years ago. During that period, there have been advances made in glass technology and fabrication which have resulted in the production of better images. This paper summarizes the latest state of the art wherein it is demonstrated that prism design should not be confined to the D line of the spectrum, but expanded to cover the uv and ir portions of the spectrum. The prism design shall cover: (1) selection of the average angle of incidence for exposure; (2) the choice of glass or other transparent media; (3) the correlationship between image and film velocity; and (4) discussion of the inherent aberrations, namely, nonlinear distortion, sagittal and tangential coma, prismatic astigmatism, change in back focus due to prism rotation; (5) shuttering action; and (6) aperture design. There have only been fragmentary data published on the subject to date. It is necessary to secure this thirty years' experience before this datum is forever lost. Recommendation for future action is made, including computer studies for optimization of design. PMID:20049049

  16. Color camera computed tomography imaging spectrometer for improved spatial-spectral image accuracy

    NASA Technical Reports Server (NTRS)

    Wilson, Daniel W. (Inventor); Bearman, Gregory H. (Inventor); Johnson, William R. (Inventor)

    2011-01-01

    Computed tomography imaging spectrometers ("CTIS"s) having color focal plane array detectors are provided. The color FPA detector may comprise a digital color camera including a digital image sensor, such as a Foveon X3.RTM. digital image sensor or a Bayer color filter mosaic. In another embodiment, the CTIS includes a pattern imposed either directly on the object scene being imaged or at the field stop aperture. The use of a color FPA detector and the pattern improves the accuracy of the captured spatial and spectral information.

  17. ATR/OTR-SY Tank Camera Purge System and in Tank Color Video Imaging System

    SciTech Connect

    Werry, S.M.

    1995-06-06

    This procedure will document the satisfactory operation of the 101-SY tank Camera Purge System (CPS) and 101-SY in tank Color Camera Video Imaging System (CCVIS). Included in the CPRS is the nitrogen purging system safety interlock which shuts down all the color video imaging system electronics within the 101-SY tank vapor space during loss of nitrogen purge pressure.

  18. A low-cost dual-camera imaging system for aerial applicators

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural aircraft provide a readily available remote sensing platform as low-cost and easy-to-use consumer-grade cameras are being increasingly used for aerial imaging. In this article, we report on a dual-camera imaging system we recently assembled that can capture RGB and near-infrared (NIR) i...

  19. Faint Object Camera imaging and spectroscopy of NGC 4151

    NASA Technical Reports Server (NTRS)

    Boksenberg, A.; Catchpole, R. M.; Macchetto, F.; Albrecht, R.; Barbieri, C.; Blades, J. C.; Crane, P.; Deharveng, J. M.; Disney, M. J.; Jakobsen, P.

    1995-01-01

    We describe ultraviolet and optical imaging and spectroscopy within the central few arcseconds of the Seyfert galaxy NGC 4151, obtained with the Faint Object Camera on the Hubble Space Telescope. A narrowband image including (O III) lambda(5007) shows a bright nucleus centered on a complex biconical structure having apparent opening angle approximately 65 deg and axis at a position angle along 65 deg-245 deg; images in bands including Lyman-alpha and C IV lambda(1550) and in the optical continuum near 5500 A, show only the bright nucleus. In an off-nuclear optical long-slit spectrum we find a high and a low radial velocity component within the narrow emission lines. We identify the low-velocity component with the bright, extended, knotty structure within the cones, and the high-velocity component with more confined diffuse emission. Also present are strong continuum emission and broad Balmer emission line components, which we attribute to the extended point spread function arising from the intense nuclear emission. Adopting the geometry pointed out by Pedlar et al. (1993) to explain the observed misalignment of the radio jets and the main optical structure we model an ionizing radiation bicone, originating within a galactic disk, with apex at the active nucleus and axis centered on the extended radio jets. We confirm that through density bounding the gross spatial structure of the emission line region can be reproduced with a wide opening angle that includes the line of sight, consistent with the presence of a simple opaque torus allowing direct view of the nucleus. In particular, our modelling reproduces the observed decrease in position angle with distance from the nucleus, progressing initially from the direction of the extended radio jet, through our optical structure, and on to the extended narrow-line region. We explore the kinematics of the narrow-line low- and high-velocity components on the basis of our spectroscopy and adopted model structure.

  20. Only Image Based for the 3d Metric Survey of Gothic Structures by Using Frame Cameras and Panoramic Cameras

    NASA Astrophysics Data System (ADS)

    Pérez Ramos, A.; Robleda Prieto, G.

    2016-06-01

    Indoor Gothic apse provides a complex environment for virtualization using imaging techniques due to its light conditions and architecture. Light entering throw large windows in combination with the apse shape makes difficult to find proper conditions to photo capture for reconstruction purposes. Thus, documentation techniques based on images are usually replaced by scanning techniques inside churches. Nevertheless, the need to use Terrestrial Laser Scanning (TLS) for indoor virtualization means a significant increase in the final surveying cost. So, in most cases, scanning techniques are used to generate dense point clouds. However, many Terrestrial Laser Scanner (TLS) internal cameras are not able to provide colour images or cannot reach the image quality that can be obtained using an external camera. Therefore, external quality images are often used to build high resolution textures of these models. This paper aims to solve the problem posted by virtualizing indoor Gothic churches, making that task more affordable using exclusively techniques base on images. It reviews a previous proposed methodology using a DSRL camera with 18-135 lens commonly used for close range photogrammetry and add another one using a HDR 360° camera with four lenses that makes the task easier and faster in comparison with the previous one. Fieldwork and office-work are simplified. The proposed methodology provides photographs in such a good conditions for building point clouds and textured meshes. Furthermore, the same imaging resources can be used to generate more deliverables without extra time consuming in the field, for instance, immersive virtual tours. In order to verify the usefulness of the method, it has been decided to apply it to the apse since it is considered one of the most complex elements of Gothic churches and it could be extended to the whole building.

  1. A new testing method of SNR for cooled CCD imaging camera based on stationary wavelet transform

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Liu, Qianshun; Yu, Feihong

    2013-08-01

    Cooled CCD (charge coupled device) imaging camera has found wide application in the field of astronomy, color photometry, spectroscopy, medical imaging, densitometry, chemiluminescence and epifluorescence imaging. A Cooled CCD (CCCD) imaging camera differs from traditional CCD/CMOS imaging camera in that Cooled CCD imaging camera can get high resolution image even in the low illumination environment. SNR (signal noise ratio) is most popular parameter of digital image quality evaluation. Many researchers have proposed various SNR testing methods for traditional CCD imaging camera, however, which is seldom suitable to Cooled CCD imaging camera because of different main noise source. In this paper, a new testing method of SNR is proposed to evaluate the quality of image captured by Cooled CCD. Stationary Wavelet Transform (SWT) is introduced in the testing method for getting more exact image SNR value. The method proposed take full advantage of SWT in the image processing, which makes the experiment results accuracy and reliable. To further refining SNR testing results, the relation between SNR and integration time is also analyzed in this article. The experimental results indicate that the testing method proposed accords with the SNR model of CCCD. In addition, the testing values for one system are about one value, which show that the proposed testing method is robust.

  2. High Performance Imaging Streak Camera for the National Ignition Facility

    SciTech Connect

    Opachich, Y. P.; Kalantar, D.; MacPhee, A.; Holder, J.; Kimbrough, J.; Bell, P. M.; Bradley, D.; Hatch, B.; Brown, C.; Landen, O.; Perfect, B. H.; Guidry, B.; Mead, A.; Charest, M.; Palmer, N.; Homoelle, D.; Browning, D.; Silbernagel, C.; Brienza-Larsen, G.; Griffin, M.; Lee, J. J.; Haugh, M. J.

    2012-01-01

    An x-ray streak camera platform has been characterized and implemented for use at the National Ignition Facility. The camera has been modified to meet the experiment requirements of the National Ignition Campaign and to perform reliably in conditions that produce high EMI. A train of temporal UV timing markers has been added to the diagnostic in order to calibrate the temporal axis of the instrument and the detector efficiency of the streak camera was improved by using a CsI photocathode. The performance of the streak camera has been characterized and is summarized in this paper. The detector efficiency and cathode measurements are also presented.

  3. LROC NAC Photometry as a Tool for Studying Physical and Compositional Properties of the Lunar Surface

    NASA Astrophysics Data System (ADS)

    Clegg, R. N.; Jolliff, B. L.; Boyd, A. K.; Stopar, J. D.; Sato, H.; Robinson, M. S.; Hapke, B. W.

    2014-10-01

    LROC NAC photometry has been used to study the effects of rocket exhaust on lunar soil properties, and here we apply the same photometric methods to place compositional constraints on regions of silicic volcanism and pure anorthosite on the Moon.

  4. Analysis of a multiple reception model for processing images from the solid-state imaging camera

    NASA Technical Reports Server (NTRS)

    Yan, T.-Y.

    1991-01-01

    A detection model to identify the presence of Galileo optical communications from an Earth-based Transmitter (GOPEX) signal by processing multiple signal receptions extracted from the camera images is described. The model decomposes a multi-signal reception camera image into a set of images so that the location of the pixel being illuminated is known a priori and the laser can illuminate only one pixel at each reception instance. Numerical results show that if effects on the pointing error due to atmospheric refraction can be controlled to between 20 to 30 microrad, the beam divergence of the GOPEX laser should be adjusted to be between 30 to 40 microrad when the spacecraft is 30 million km away from Earth. Furthermore, increasing beyond 5 the number of receptions for processing will not produce a significant detection probability advantage.

  5. Toward an image compression algorithm for the high-resolution electronic still camera

    NASA Technical Reports Server (NTRS)

    Nerheim, Rosalee

    1989-01-01

    Taking pictures with a camera that uses a digital recording medium instead of film has the advantage of recording and transmitting images without the use of a darkroom or a courier. However, high-resolution images contain an enormous amount of information and strain data-storage systems. Image compression will allow multiple images to be stored in the High-Resolution Electronic Still Camera. The camera is under development at Johnson Space Center. Fidelity of the reproduced image and compression speed are of tantamount importance. Lossless compression algorithms are fast and faithfully reproduce the image, but their compression ratios will be unacceptably low due to noise in the front end of the camera. Future efforts will include exploring methods that will reduce the noise in the image and increase the compression ratio.

  6. Fly's Eye camera system: optical imaging using a hexapod platform

    NASA Astrophysics Data System (ADS)

    Jaskó, Attila; Pál, András.; Vida, Krisztián.; Mészáros, László; Csépány, Gergely; Mező, György

    2014-07-01

    The Fly's Eye Project is a high resolution, high coverage time-domain survey in multiple optical passbands: our goal is to cover the entire visible sky above the 30° horizontal altitude with a cadence of ~3 min. Imaging is going to be performed by 19 wide-field cameras mounted on a hexapod platform resembling a fly's eye. Using a hexapod developed and built by our team allows us to create a highly fault-tolerant instrument that uses the sky as a reference to define its own tracking motion. The virtual axis of the platform is automatically aligned with the Earth's rotational axis; therefore the same mechanics can be used independently from the geographical location of the device. Its enclosure makes it capable of autonomous observing and withstanding harsh environmental conditions. We briefly introduce the electrical, mechanical and optical design concepts of the instrument and summarize our early results, focusing on sidereal tracking. Due to the hexapod design and hence the construction is independent from the actual location, it is considerably easier to build, install and operate a network of such devices around the world.

  7. Experimental research on thermoelectric cooler for imager camera thermal control

    NASA Astrophysics Data System (ADS)

    Hu, Bing-ting; Kang, Ao-feng; Fu, Xin; Jiang, Shi-chen; Dong, Yao-hai

    2013-09-01

    Conventional passive thermal design failed to satisfy CCD's temperature requirement on a geostationary earth orbit satellite Imager camera because of the high power and low working temperature, leading to utilization of thermoelectric cooler (TEC) for heat dissipation. TEC was used in conjunction with the external radiator in the CCDs' thermal design. In order to maintain the CCDs at low working temperature, experimental research on the performance of thermoelectric cooler was necessary and the results could be the guide for the application of TEC in different conditions. The experimental system to evaluate the performance of TEC was designed and built, consisting of TEC, heat pipe, TEC mounting plate, radiator and heater. A series of TEC performance tests were conducted for domestic and oversea TECs in thermal vacuum environment. The effects of TEC's mounting, input power and heat load on the temperature difference of TEC's cold and hot face were explored. Results demonstrated that the temperature difference of TEC's cold and hot face was slightly increased when TEC's operating voltage reached 80% of rating voltage, which caused the temperature rise of TEC's hot face. It recommended TEC to operate at low voltage. Based on experiment results, thermal analysis indicated that the temperature difference of TEC's cold and hot face could satisfy the temperature requirement and still had surplus.

  8. Hubble Space Telescope Planetary Camera images of R136

    NASA Technical Reports Server (NTRS)

    Campbell, Bel; Hunter, Deidre A.; Holtzman, Jon A.; Lauer, Tod R.; Shaya, Edward J.; Code, Arthur; Faber, S. M.; Groth, Edward J.; Light, Robert M.; Lynds, Roger

    1992-01-01

    Images obtained with the Planetary Camera on the HST is used here to study the stellar population of R136, the core of the 30 Doradus cluster. It is found that R136a, the brightest knot at the center of R136, is indeed a tight cluster of stars containing at least 12 components in a 1 arcsec region. Three of the stars are of the Wolf-Rayet (W-R) type. The brightest stars have luminosities consistent with their being massive O supergiants or W-R stars. The stellar mass density in R136a is at least a million tiems that of the solar neighborhood. In the larger region known as R136, the magnitudes of 214 stars are detected and measured. A color-magnitude diagram shows a range of stars from luminous O supergiants to ZAMS B3 stars. The diagram is very similar to that of stars outside of R136. A surface brightness profile constructed from stellar photometry is best fit by a pure power law.

  9. PET imaging using gamma camera systems: a review.

    PubMed

    Jarritt, P H; Acton, P D

    1996-09-01

    Optimized positron emission tomographs have begun to demonstrate an ever widening range of clinical applications for positron labelled pharmaceuticals. This potential has led to a renewed interest in the use of the more widely available Anger gamma camera detectors for imaging the 511 keV photons from the positron decay process. Two forms of detection can be considered: either the detection of the 511 keV photons as single events or the detection of coincidence events from the opposed pair annihilation photons. The widespread availability of dual, opposed-pair, large field-of-view detectors has promoted the development of coincidence detection without collimation. With detector rotation, positron emission tomography (PET) can be performed. An alternative and lower cost option has been the universal development of ultra high-energy collimators to perform single photon emission tomography (SPET) with 511 keV photons. This review outlines the currently available performance characteristics of these two approaches and compares them with those from two- and three-dimensional PET optimized systems. The limitations on the development of these systems is discussed through the analysis of the principles underlying both single photon and coincidence detection. Preliminary clinical experience indicates that limitations in the performance characteristics of these systems has implications for their potential role, although applications in cardiology and oncology are being pursued. PMID:8895903

  10. Cloud Detection with the Earth Polychromatic Imaging Camera (EPIC)

    NASA Technical Reports Server (NTRS)

    Meyer, Kerry; Marshak, Alexander; Lyapustin, Alexei; Torres, Omar; Wang, Yugie

    2011-01-01

    The Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR) would provide a unique opportunity for Earth and atmospheric research due not only to its Lagrange point sun-synchronous orbit, but also to the potential for synergistic use of spectral channels in both the UV and visible spectrum. As a prerequisite for most applications, the ability to detect the presence of clouds in a given field of view, known as cloud masking, is of utmost importance. It serves to determine both the potential for cloud contamination in clear-sky applications (e.g., land surface products and aerosol retrievals) and clear-sky contamination in cloud applications (e.g., cloud height and property retrievals). To this end, a preliminary cloud mask algorithm has been developed for EPIC that applies thresholds to reflected UV and visible radiances, as well as to reflected radiance ratios. This algorithm has been tested with simulated EPIC radiances over both land and ocean scenes, with satisfactory results. These test results, as well as algorithm sensitivity to potential instrument uncertainties, will be presented.

  11. Stereo Reconstruction of Atmospheric Cloud Surfaces from Fish-Eye Camera Images

    NASA Astrophysics Data System (ADS)

    Katai-Urban, G.; Otte, V.; Kees, N.; Megyesi, Z.; Bixel, P. S.

    2016-06-01

    In this article a method for reconstructing atmospheric cloud surfaces using a stereo camera system is presented. The proposed camera system utilizes fish-eye lenses in a flexible wide baseline camera setup. The entire workflow from the camera calibration to the creation of the 3D point set is discussed, but the focus is mainly on cloud segmentation and on the image processing steps of stereo reconstruction. Speed requirements, geometric limitations, and possible extensions of the presented method are also covered. After evaluating the proposed method on artificial cloud images, this paper concludes with results and discussion of possible applications for such systems.

  12. A novel ultra-high speed camera for digital image processing applications

    NASA Astrophysics Data System (ADS)

    Hijazi, A.; Madhavan, V.

    2008-08-01

    Multi-channel gated-intensified cameras are commonly used for capturing images at ultra-high frame rates. The use of image intensifiers reduces the image resolution and increases the error in applications requiring high-quality images, such as digital image correlation. We report the development of a new type of non-intensified multi-channel camera system that permits recording of image sequences at ultra-high frame rates at the native resolution afforded by the imaging optics and the cameras used. This camera system is based upon the concept of using a sequence of short-duration light pulses of different wavelengths for illumination and using wavelength selective elements in the imaging system to route each particular wavelength of light to a particular camera. As such, the duration of the light pulses controls the exposure time and the timing of the light pulses controls the interframe time. A prototype camera system built according to this concept comprises four dual-frame cameras synchronized with four dual-cavity pulsed lasers producing 5 ns pulses in four different wavelengths. The prototype is capable of recording four-frame full-resolution image sequences at frame rates up to 200 MHz and eight-frame image sequences at frame rates up to 8 MHz. This system is built around a stereo microscope to capture stereoscopic image sequences usable for 3D digital image correlation. The camera system is used for imaging the chip-workpiece interface area during high speed machining, and the images are used to map the strain rate in the primary shear zone.

  13. High-speed camera with internal real-time image processing

    NASA Astrophysics Data System (ADS)

    Paindavoine, M.; Mosqueron, R.; Dubois, J.; Clerc, C.; Grapin, J. C.; Tomasini, F.

    2005-08-01

    High-speed video cameras are powerful tools for investigating for instance the dynamics of fluids or the movements of mechanical parts in manufacturing processes. In the past years, the use of CMOS sensors instead of CCDs have made possible the development of high-speed video cameras offering digital outputs, readout flexibility and lower manufacturing costs. In this field, we designed a new fast CMOS camera with a 1280×1024 pixels resolution at 500 fps. In order to transmit from the camera only useful information from the fast images, we studied some specific algorithms like edge detection, wavelet analysis, image compression and object tracking. These image processing algorithms have been implemented into a FPGA embedded inside the camera. This FPGA technology allows us to process fast images in real time.

  14. Rapid 360 degree imaging and stitching of 3D objects using multiple precision 3D cameras

    NASA Astrophysics Data System (ADS)

    Lu, Thomas; Yin, Stuart; Zhang, Jianzhong; Li, Jiangan; Wu, Frank

    2008-02-01

    In this paper, we present the system architecture of a 360 degree view 3D imaging system. The system consists of multiple 3D sensors synchronized to take 3D images around the object. Each 3D camera employs a single high-resolution digital camera and a color-coded light projector. The cameras are synchronized to rapidly capture the 3D and color information of a static object or a live person. The color encoded structure lighting ensures the precise reconstruction of the depth of the object. A 3D imaging system architecture is presented. The architecture employs the displacement of the camera and the projector to triangulate the depth information. The 3D camera system has achieved high depth resolution down to 0.1mm on a human head sized object and 360 degree imaging capability.

  15. Development of filter exchangeable 3CCD camera for multispectral imaging acquisition

    NASA Astrophysics Data System (ADS)

    Lee, Hoyoung; Park, Soo Hyun; Kim, Moon S.; Noh, Sang Ha

    2012-05-01

    There are a lot of methods to acquire multispectral images. Dynamic band selective and area-scan multispectral camera has not developed yet. This research focused on development of a filter exchangeable 3CCD camera which is modified from the conventional 3CCD camera. The camera consists of F-mounted lens, image splitter without dichroic coating, three bandpass filters, three image sensors, filer exchangeable frame and electric circuit for parallel image signal processing. In addition firmware and application software have developed. Remarkable improvements compared to a conventional 3CCD camera are its redesigned image splitter and filter exchangeable frame. Computer simulation is required to visualize a pathway of ray inside of prism when redesigning image splitter. Then the dimensions of splitter are determined by computer simulation which has options of BK7 glass and non-dichroic coating. These properties have been considered to obtain full wavelength rays on all film planes. The image splitter is verified by two line lasers with narrow waveband. The filter exchangeable frame is designed to make swap bandpass filters without displacement change of image sensors on film plane. The developed 3CCD camera is evaluated to application of detection to scab and bruise on Fuji apple. As a result, filter exchangeable 3CCD camera could give meaningful functionality for various multispectral applications which need to exchange bandpass filter.

  16. Applications of the BAE SYSTEMS MicroIR uncooled infrared thermal imaging cameras

    NASA Astrophysics Data System (ADS)

    Wickman, Heather A.; Henebury, John J., Jr.; Long, Dennis R.

    2003-09-01

    MicroIR uncooled infrared imaging modules (based on VOx microbolometers), developed and manufactured at BAE SYSTEMS, are integrated into ruggedized, weatherproof camera systems and are currently supporting numerous security and surveillance applications. The introduction of uncooled thermal imaging has permitted the expansion of traditional surveillance and security perimeters. MicroIR cameras go beyond the imagery limits of visible and low-light short wavelength infrared sensors, providing continual, uninterrupted, high quality imagery both day and night. Coupled with an appropriate lens assembly, MicroIR cameras offer exemplary imagery performance that lends itself to a more comprehensive level of surveillance. With the current increased emphasis on security and surveillance, MicroIR Cameras are evolving as an unquestionably beneficial instrument in the security and surveillance arenas. This paper will elaborate on the attributes of the cameras, and discuss the development and the deployment, both present and future, of BAE SYSTEMS MicroIR Cameras.

  17. A hybrid version of the Whipple observatory's air Cherenkov imaging camera for use in moonlight

    NASA Astrophysics Data System (ADS)

    Chantell, M. C.; Akerlof, C. W.; Badran, H. M.; Buckley, J.; Carter-Lewis, D. A.; Cawley, M. F.; Connaughton, V.; Fegan, D. J.; Fleury, P.; Gaidos, J.; Hillas, A. M.; Lamb, R. C.; Pare, E.; Rose, H. J.; Rovero, A. C.; Sarazin, X.; Sembroski, G.; Schubnell, M. S.; Urban, M.; Weekes, T. C.; Wilson, C.

    1997-02-01

    A hybrid version of the Whipple Observatory's atmospheric Cherenkov imaging camera that permits observation during periods of bright moonlight is described. The hybrid camera combines a blue-light blocking filter with the standard Whipple imaging camera to reduce sensitivity to wavelengths greater than 360 nm. Data taken with this camera are found to be free from the effects of the moonlit night-sky after the application of simple off-line noise filtering. This camera has been used to successfully detect TeV gamma rays, in bright moon light, from both the Crab Nebula and the active galactic nucleus Markarian 421 at the 4.9σ and 3.9σ levels of statistical significance, respectively. The energy threshold of the camera is estimated to be 1.1 ( +0.6/-0.3) TeV from Monte Carlo simulations.

  18. Modelling of Camera Phone Capture Channel for JPEG Colour Barcode Images

    NASA Astrophysics Data System (ADS)

    Tan, Keng T.; Ong, Siong Khai; Chai, Douglas

    As camera phones have permeated into our everyday lives, two dimensional (2D) barcode has attracted researchers and developers as a cost-effective ubiquitous computing tool. A variety of 2D barcodes and their applications have been developed. Often, only monochrome 2D barcodes are used due to their robustness in an uncontrolled operating environment of camera phones. However, we are seeing an emerging use of colour 2D barcodes for camera phones. Nonetheless, using a greater multitude of colours introduces errors that can negatively affect the robustness of barcode reading. This is especially true when developing a 2D barcode for camera phones which capture and store these barcode images in the baseline JPEG format. This paper present one aspect of the errors introduced by such camera phones by modelling the camera phone capture channel for JPEG colour barcode images.

  19. Method for quantifying image quality in push-broom hyperspectral cameras

    NASA Astrophysics Data System (ADS)

    Høye, Gudrun; Løke, Trond; Fridman, Andrei

    2015-05-01

    We propose a method for measuring and quantifying image quality in push-broom hyperspectral cameras in terms of spatial misregistration caused by keystone and variations in the point spread function (PSF) across spectral channels, and image sharpness. The method is suitable for both traditional push-broom hyperspectral cameras where keystone is corrected in hardware and cameras where keystone is corrected in postprocessing, such as resampling and mixel cameras. We show how the measured camera performance can be presented graphically in an intuitive and easy to understand way, comprising both image sharpness and spatial misregistration in the same figure. For the misregistration, we suggest that both the mean standard deviation and the maximum value for each pixel are shown. We also suggest how the method could be expanded to quantify spectral misregistration caused by the smile effect and corresponding PSF variations. Finally, we have measured the performance of two HySpex SWIR 384 cameras using the suggested method. The method appears well suited for assessing camera quality and for comparing the performance of different hyperspectral imagers and could become the future standard for how to measure and quantify the image quality of push-broom hyperspectral cameras.

  20. Patient-initiated camera phone images in general practice: a qualitative study of illustrated narratives

    PubMed Central

    Tan, Lawrence; Hu, Wendy; Brooker, Ron

    2014-01-01

    Background Camera phones have become ubiquitous in the digital age. Patients are beginning to bring images recorded on their mobile phones to share with their GP during medical consultations. Aim To explore GP perceptions about the effect of patient-initiated camera phone images on the consultation. Design and setting An interview study of GPs based in rural and urban locations in Australia. Methods Semi-structured telephone interviews with nine GPs about their experiences with patient-initiated camera phone images. Results GPs described how patient-initiated camera phone photos and videos contributed to the diagnostic process, management and continuity of care. These images gave GPs in the study additional insight into the patient’s world. Potential harm resulting from inappropriate use of camera phones by patients was also identified. Conclusion Patient-initiated camera phone images can empower patients by illustrating their narratives, thus contributing to improved communication in general practice. Potential harm could result from inappropriate use of these images. GPs shown images on patients’ camera phones should make the most of this opportunity for improved understanding of the patient’s world. There are however, potential medicolegal implications such as informed consent, protection of patient and doctor privacy, and the risk of misdiagnosis. PMID:24771843

  1. The Potential of Dual Camera Systems for Multimodal Imaging of Cardiac Electrophysiology and Metabolism

    PubMed Central

    Holcomb, Mark R.; Woods, Marcella C.; Uzelac, Ilija; Wikswo, John P.; Gilligan, Jonathan M.; Sidorov, Veniamin Y.

    2013-01-01

    Fluorescence imaging has become a common modality in cardiac electrodynamics. A single fluorescent parameter is typically measured. Given the growing emphasis on simultaneous imaging of more than one cardiac variable, we present an analysis of the potential of dual camera imaging, using as an example our straightforward dual camera system that allows simultaneous measurement of two dynamic quantities from the same region of the heart. The advantages of our system over others include an optional software camera calibration routine that eliminates the need for precise camera alignment. The system allows for rapid setup, dichroic image separation, dual-rate imaging, and high spatial resolution, and it is generally applicable to any two-camera measurement. This type of imaging system offers the potential for recording simultaneously not only transmembrane potential and intracellular calcium, two frequently measured quantities, but also other signals more directly related to myocardial metabolism, such as [K+]e, NADH, and reactive oxygen species, leading to the possibility of correlative multimodal cardiac imaging. We provide a compilation of dye and camera information critical to the design of dual camera systems and experiments. PMID:19657065

  2. Measurement of modulation transfer function for four types of imaging elements used in fast cameras

    SciTech Connect

    Estrella, R.M.; Sammons, T.J. . Amador Valley Operations); Thomas, S.W. )

    1991-01-01

    We have measured the modulation transfer function (MTF) of fiber- optic bundles (reducers), minifiers (inverting, electrostatically focused imaging tube reducers), microchannel plate image intensifiers (MCPIs), and streak tubes as part of our ongoing device evaluation program aimed at precise characterization of various imaging elements used in fast cameras. This paper describes our measurement equipment and techniques and shows plots of MTF measurements for each of four types of fast-camera elements tested. 6 refs., 9 figs.

  3. Effects of frame rate and image resolution on pulse rate measured using multiple camera imaging photoplethysmography

    NASA Astrophysics Data System (ADS)

    Blackford, Ethan B.; Estepp, Justin R.

    2015-03-01

    Non-contact, imaging photoplethysmography uses cameras to facilitate measurements including pulse rate, pulse rate variability, respiration rate, and blood perfusion by measuring characteristic changes in light absorption at the skin's surface resulting from changes in blood volume in the superficial microvasculature. Several factors may affect the accuracy of the physiological measurement including imager frame rate, resolution, compression, lighting conditions, image background, participant skin tone, and participant motion. Before this method can gain wider use outside basic research settings, its constraints and capabilities must be well understood. Recently, we presented a novel approach utilizing a synchronized, nine-camera, semicircular array backed by measurement of an electrocardiogram and fingertip reflectance photoplethysmogram. Twenty-five individuals participated in six, five-minute, controlled head motion artifact trials in front of a black and dynamic color backdrop. Increasing the input channel space for blind source separation using the camera array was effective in mitigating error from head motion artifact. Herein we present the effects of lower frame rates at 60 and 30 (reduced from 120) frames per second and reduced image resolution at 329x246 pixels (one-quarter of the original 658x492 pixel resolution) using bilinear and zero-order downsampling. This is the first time these factors have been examined for a multiple imager array and align well with previous findings utilizing a single imager. Examining windowed pulse rates, there is little observable difference in mean absolute error or error distributions resulting from reduced frame rates or image resolution, thus lowering requirements for systems measuring pulse rate over sufficient length time windows.

  4. D Hyperspectral Frame Imager Camera Data in Photogrammetric Mosaicking

    NASA Astrophysics Data System (ADS)

    Mäkeläinen, A.; Saari, H.; Hippi, I.; Sarkeala, J.; Soukkamäki, J.

    2013-08-01

    A new 2D hyperspectral frame camera system has been developed by VTT (Technical Research Center of Finland) and Rikola Ltd. It contains frame based and very light camera with RGB-NIR sensor and it is suitable for light weight and cost effective UAV planes. MosaicMill Ltd. has converted the camera data into proper format for photogrammetric processing, and camera's geometrical accuracy and stability are evaluated to guarantee required accuracies for end user applications. MosaicMill Ltd. has also applied its' EnsoMOSAIC technology to process hyperspectral data into orthomosaics. This article describes the main steps and results on applying hyperspectral sensor in orthomosaicking. The most promising results as well as challenges in agriculture and forestry are also described.

  5. Face acquisition camera design using the NV-IPM image generation tool

    NASA Astrophysics Data System (ADS)

    Howell, Christopher L.; Choi, Hee-Sue; Reynolds, Joseph P.

    2015-05-01

    In this paper, we demonstrate the utility of the Night Vision Integrated Performance Model (NV-IPM) image generation tool by using it to create a database of face images with controlled degradations. Available face recognition algorithms can then be used to directly evaluate camera designs using these degraded images. By controlling camera effects such as blur, noise, and sampling, we can analyze algorithm performance and establish a more complete performance standard for face acquisition cameras. The ability to accurately simulate imagery and directly test with algorithms not only improves the system design process but greatly reduces development cost.

  6. The advantages of using a Lucky Imaging camera for observations of microlensing events

    NASA Astrophysics Data System (ADS)

    Sajadian, Sedighe; Rahvar, Sohrab; Dominik, Martin; Hundertmark, Markus

    2016-05-01

    In this work, we study the advantages of using a Lucky Imaging camera for the observations of potential planetary microlensing events. Our aim is to reduce the blending effect and enhance exoplanet signals in binary lensing systems composed of an exoplanet and the corresponding parent star. We simulate planetary microlensing light curves based on present microlensing surveys and follow-up telescopes where one of them is equipped with a Lucky Imaging camera. This camera is used at the Danish 1.54-m follow-up telescope. Using a specific observational strategy, for an Earth-mass planet in the resonance regime, where the detection probability in crowded fields is smaller, Lucky Imaging observations improve the detection efficiency which reaches 2 per cent. Given the difficulty of detecting the signal of an Earth-mass planet in crowded-field imaging even in the resonance regime with conventional cameras, we show that Lucky Imaging can substantially improve the detection efficiency.

  7. Mass movement slope streaks imaged by the Mars Orbiter Camera

    NASA Astrophysics Data System (ADS)

    Sullivan, Robert; Thomas, Peter; Veverka, Joseph; Malin, Michael; Edgett, Kenneth S.

    2001-10-01

    Narrow, fan-shaped dark streaks on steep Martian slopes were originally observed in Viking Orbiter images, but a definitive explanation was not possible because of resolution limitations. Pictures acquired by the Mars Orbiter Camera (MOC) aboard the Mars Global Surveyor (MGS) spacecraft show innumerable examples of dark slope streaks distributed widely, but not uniformly, across the brighter equatorial regions, as well as individual details of these features that were not visible in Viking Orbiter data. Dark slope streaks (as well as much rarer bright slope streaks) represent one of the most widespread and easily recognized styles of mass movement currently affecting the Martian surface. New dark streaks have formed since Viking and even during the MGS mission, confirming earlier suppositions that higher contrast dark streaks are younger, and fade (brighten) with time. The darkest slope streaks represent ~10% contrast with surrounding slope materials. No small outcrops supplying dark material (or bright material, for bright streaks) have been found at streak apexes. Digitate downslope ends indicate slope streak formation involves a ground-hugging flow subject to deflection by minor topographic obstacles. The model we favor explains most dark slope streaks as scars from dust avalanches following oversteepening of air fall deposits. This process is analogous to terrestrial avalanches of oversteepened dry, loose snow which produce shallow avalanche scars with similar morphologies. Low angles of internal friction typically 10-30¡ for terrestrial loess and clay materials suggest that mass movement of (low-cohesion) Martian dusty air fall is possible on a wide range of gradients. Martian gravity, presumed low density of the air fall deposits, and thin (unresolved by MOC) failed layer depths imply extremely low cohesive strength at time of failure, consistent with expectations for an air fall deposit of dust particles. As speed increases during a dust avalanche, a

  8. Imaging Asteroid 4 Vesta Using the Framing Camera

    NASA Technical Reports Server (NTRS)

    Keller, H. Uwe; Nathues, Andreas; Coradini, Angioletta; Jaumann, Ralf; Jorda, Laurent; Li, Jian-Yang; Mittlefehldt, David W.; Mottola, Stefano; Raymond, C. A.; Schroeder, Stefan E.

    2011-01-01

    The Framing Camera (FC) onboard the Dawn spacecraft serves a dual purpose. Next to its central role as a prime science instrument it is also used for the complex navigation of the ion drive spacecraft. The CCD detector with 1024 by 1024 pixels provides the stability for a multiyear mission and its high requirements of photometric accuracy over the wavelength band from 400 to 1000 nm covered by 7 band-pass filters. Vesta will be observed from 3 orbit stages with image scales of 227, 63, and 17 m/px, respectively. The mapping of Vesta s surface with medium resolution will be only completed during the exit phase when the north pole will be illuminated. A detailed pointing strategy will cover the surface at least twice at similar phase angles to provide stereo views for reconstruction of the topography. During approach the phase function of Vesta was determined over a range of angles not accessible from earth. This is the first step in deriving the photometric function of the surface. Combining the topography based on stereo tie points with the photometry in an iterative procedure will disclose details of the surface morphology at considerably smaller scales than the pixel scale. The 7 color filters are well positioned to provide information on the spectral slope in the visible, the depth of the strong pyroxene absorption band, and their variability over the surface. Cross calibration with the VIR spectrometer that extends into the near IR will provide detailed maps of Vesta s surface mineralogy and physical properties. Georeferencing all these observation will result in a coherent and unique data set. During Dawn s approach and capture FC has already demonstrated its performance. The strong variation observed by the Hubble Space Telescope can now be correlated with surface units and features. We will report on results obtained from images taken during survey mode covering the whole illuminated surface. Vesta is a planet-like differentiated body, but its surface

  9. An airborne multispectral imaging system based on two consumer-grade cameras for agricultural remote sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the design and evaluation of an airborne multispectral imaging system based on two identical consumer-grade cameras for agricultural remote sensing. The cameras are equipped with a full-frame complementary metal oxide semiconductor (CMOS) sensor with 5616 × 3744 pixels. One came...

  10. Compact large FoV gamma camera for breast molecular imaging

    NASA Astrophysics Data System (ADS)

    Pani, R.; Cinti, M. N.; Pellegrini, R.; Betti, M.; Devincentis, G.; Bennati, P.; Ridolfi, S.; Iurlaro, G.; Montani, L.; Scafè, R.; Marini, M.; Porfiri, L. M.; Giachetti, G.; Baglini, F.; Salvadori, G.; Madesani, M.; Pieracci, M.; Catarsi, F.; Bigongiari, A.

    2006-12-01

    The very low sensitivity of scintimammography for tumours under 1 cm in diameter, with current nuclear medicine cameras, is the major limitation in recommending this test modality for screening purposes. To improve this diagnostic technique,a new concept of scintillation gamma camera, which fits the best requirements for functional breast imaging has been developed under "Integrated Mammographic Imaging" (IMI) project. This camera consists of a large detection head (6″×7″),very compact sized and with light weight to be easily positioned in the same X-ray geometry. The detection head consists of matrix of 42 photodetector Hamamatsu 1 in 2 square H8520-C12 PSPMTs, which are closely packed and coupled to a NaI(Tl) scintillating array, with individual crystal pixel 2×2×6 mm 3 size. Large FoV camera shows a very good pixel identification in the detection dead zones between tubes allowing an accurate LUT correction of the final image reconstruction. Electronic read-out was especially designed to optimize the intrinsic spatial resolution and camera compactness. With respect to Anger camera, the overall spatial resolution is improved up to 40% while the overall energy resolution values is ˜16% at 140 keV. Large FoV dedicated camera was characterized and tested by phantom studies; and clinical trials are currently performed. For all patients, compression views have been acquiring for both breasts in craniocaudal projections, and are compared with standard gamma camera images.

  11. Comparison of three thermal cameras with canine hip area thermographic images.

    PubMed

    Vainionpää, Mari; Raekallio, Marja; Tuhkalainen, Elina; Hänninen, Hannele; Alhopuro, Noora; Savolainen, Maija; Junnila, Jouni; Hielm-Björkman, Anna; Snellman, Marjatta; Vainio, Outi

    2012-12-01

    The objective of this study was to compare the method of thermography by using three different resolution thermal cameras and basic software for thermographic images, separating the two persons taking the thermographic images (thermographers) from the three persons interpreting the thermographic images (interpreters). This was accomplished by studying the repeatability between thermographers and interpreters. Forty-nine client-owned dogs of 26 breeds were enrolled in the study. The thermal cameras used were of different resolutions-80 × 80, 180 × 180 and 320 × 240 pixels. Two trained thermographers took thermographic images of the hip area in all dogs using all three cameras. A total of six thermographic images per dog were taken. The thermographic images were analyzed using appropriate computer software, FLIR QuickReport 2.1. Three trained interpreters independently evaluated the mean temperatures of hip joint areas of the six thermographic images for each dog. The repeatability between thermographers was >0.975 with the two higher-resolution cameras and 0.927 with the lowest resolution camera. The repeatability between interpreters was >0.97 with each camera. Thus, the between-interpreter variation was small. The repeatability between thermographers and interpreters was considered high enough to encourage further studies with thermographic imaging in dogs. PMID:22785576

  12. Photometric Calibration and Image Stitching for a Large Field of View Multi-Camera System.

    PubMed

    Lu, Yu; Wang, Keyi; Fan, Gongshu

    2016-01-01

    A new compact large field of view (FOV) multi-camera system is introduced. The camera is based on seven tiny complementary metal-oxide-semiconductor sensor modules covering over 160° × 160° FOV. Although image stitching has been studied extensively, sensor and lens differences have not been considered in previous multi-camera devices. In this study, we have calibrated the photometric characteristics of the multi-camera device. Lenses were not mounted on the sensor in the process of radiometric response calibration to eliminate the influence of the focusing effect of uniform light from an integrating sphere. Linearity range of the radiometric response, non-linearity response characteristics, sensitivity, and dark current of the camera response function are presented. The R, G, and B channels have different responses for the same illuminance. Vignetting artifact patterns have been tested. The actual luminance of the object is retrieved by sensor calibration results, and is used to blend images to make panoramas reflect the objective luminance more objectively. This compensates for the limitation of stitching images that are more realistic only through the smoothing method. The dynamic range limitation of can be resolved by using multiple cameras that cover a large field of view instead of a single image sensor with a wide-angle lens. The dynamic range is expanded by 48-fold in this system. We can obtain seven images in one shot with this multi-camera system, at 13 frames per second. PMID:27077857

  13. Photometric Calibration and Image Stitching for a Large Field of View Multi-Camera System

    PubMed Central

    Lu, Yu; Wang, Keyi; Fan, Gongshu

    2016-01-01

    A new compact large field of view (FOV) multi-camera system is introduced. The camera is based on seven tiny complementary metal-oxide-semiconductor sensor modules covering over 160° × 160° FOV. Although image stitching has been studied extensively, sensor and lens differences have not been considered in previous multi-camera devices. In this study, we have calibrated the photometric characteristics of the multi-camera device. Lenses were not mounted on the sensor in the process of radiometric response calibration to eliminate the influence of the focusing effect of uniform light from an integrating sphere. Linearity range of the radiometric response, non-linearity response characteristics, sensitivity, and dark current of the camera response function are presented. The R, G, and B channels have different responses for the same illuminance. Vignetting artifact patterns have been tested. The actual luminance of the object is retrieved by sensor calibration results, and is used to blend images to make panoramas reflect the objective luminance more objectively. This compensates for the limitation of stitching images that are more realistic only through the smoothing method. The dynamic range limitation of can be resolved by using multiple cameras that cover a large field of view instead of a single image sensor with a wide-angle lens. The dynamic range is expanded by 48-fold in this system. We can obtain seven images in one shot with this multi-camera system, at 13 frames per second. PMID:27077857

  14. A Prediction Method of TV Camera Image for Space Manual-control Rendezvous and Docking

    NASA Astrophysics Data System (ADS)

    Zhen, Huang; Qing, Yang; Wenrui, Wu

    Space manual-control rendezvous and docking (RVD) is a key technology for accomplishing the RVD mission in manned space engineering, especially when automatic control system is out of work. The pilot on chase spacecraft manipulates the hand-stick by the image of target spacecraft captured by TV camera. From the TV image, the relative position and attitude of chase and target spacecrafts can be shown. Therefore, the size, the position, the brightness and the shadow of the target on TV camera are key to guarantee the success of manual-control RVD. A method of predicting the on-orbit TV camera image at different relative positions and light conditions during the process of RVD is discussed. Firstly, the basic principle of capturing the image of cross drone on target spacecraft by TV camera is analyzed theoretically, based which the strategy of manual-control RVD is discussed in detail. Secondly, the relationship between the displayed size or position and the real relative distance of chase and target spacecrafts is presented, the brightness and reflection by the target spacecraft at different light conditions are decribed, the shadow on cross drone caused by the chase or target spacecraft is analyzed. Thirdly, a prediction method of on-orbit TV camera images at certain orbit and light condition is provided, and the characteristics of TV camera image during the RVD is analyzed. Finally, the size, the position, the brightness and the shadow of target spacecraft on TV camera image at typical orbit is simulated. The result, by comparing the simulated images with the real images captured by the TV camera on Shenzhou manned spaceship , shows that the prediction method is reasonable

  15. A New Lunar Atlas: Mapping the Moon with the Wide Angle Camera

    NASA Astrophysics Data System (ADS)

    Speyerer, E.; Robinson, M. S.; Boyd, A.; Sato, H.

    2012-12-01

    The Lunar Reconnaissance Orbiter (LRO) spacecraft launched in June 2009 and began systematically mapping the lunar surface and providing a priceless dataset for the planetary science community and future mission planners. From 20 September 2009 to 11 December 2011, the spacecraft was in a nominal 50 km polar orbit, except for two one-month long periods when a series of spacecraft maneuvers enabled low attitude flyovers (as low as 22 km) of key exploration and scientifically interesting targets. One of the instruments, the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) [1], captured nearly continuous synoptic views of the illuminated lunar surface. The WAC is a 7-band (321, 360, 415, 566, 604, 643, 689 nm) push frame imager with field of view of 60° in color mode and 90° in monochrome mode. This broad field of view enables the WAC to reimage nearly 50% (at the equator where the orbit tracks our spaced the furthest) of the terrain it imaged in the previous orbit. The visible bands of map projected WAC images have a pixel scale of 100 m, while UV bands have a pixel scale of 400 m due to 4x4 pixel on-chip binning that increases signal-to-noise. The nearly circular polar orbit and short (two hour) orbital periods enable seamless mosaics of broad areas of the surface with uniform lighting and resolution. In March of 2011, the LROC team released the first version of the global monochrome (643nm) morphologic map [2], which was comprised of 15,000 WAC images collected over three periods. With the over 130,000 WAC images collected while the spacecraft was in the 50 km orbit, a new set of mosaics are being produced by the LROC Team and will be released to the Planetary Data Systems. These new maps include an updated morphologic map with an improved set of images (limiting illumination variations and gores due to off-nadir observation of other instruments) and a new photometric correction derived from the LROC WAC dataset. In addition, a higher sun (lower

  16. No-reference sharpness assessment of camera-shaken images by analysis of spectral structure.

    PubMed

    Oh, Taegeun; Park, Jincheol; Seshadrinathan, Kalpana; Lee, Sanghoon; Bovik, Alan Conrad

    2014-12-01

    The tremendous explosion of image-, video-, and audio-enabled mobile devices, such as tablets and smart-phones in recent years, has led to an associated dramatic increase in the volume of captured and distributed multimedia content. In particular, the number of digital photographs being captured annually is approaching 100 billion in just the U.S. These pictures are increasingly being acquired by inexperienced, casual users under highly diverse conditions leading to a plethora of distortions, including blur induced by camera shake. In order to be able to automatically detect, correct, or cull images impaired by shake-induced blur, it is necessary to develop distortion models specific to and suitable for assessing the sharpness of camera-shaken images. Toward this goal, we have developed a no-reference framework for automatically predicting the perceptual quality of camera-shaken images based on their spectral statistics. Two kinds of features are defined that capture blur induced by camera shake. One is a directional feature, which measures the variation of the image spectrum across orientations. The second feature captures the shape, area, and orientation of the spectral contours of camera shaken images. We demonstrate the performance of an algorithm derived from these features on new and existing databases of images distorted by camera shake. PMID:25350928

  17. Single camera imaging system for color and near-infrared fluorescence image guided surgery

    PubMed Central

    Chen, Zhenyue; Zhu, Nan; Pacheco, Shaun; Wang, Xia; Liang, Rongguang

    2014-01-01

    Near-infrared (NIR) fluorescence imaging systems have been developed for image guided surgery in recent years. However, current systems are typically bulky and work only when surgical light in the operating room (OR) is off. We propose a single camera imaging system that is capable of capturing NIR fluorescence and color images under normal surgical lighting illumination. Using a new RGB-NIR sensor and synchronized NIR excitation illumination, we have demonstrated that the system can acquire both color information and fluorescence signal with high sensitivity under normal surgical lighting illumination. The experimental results show that ICG sample with concentration of 0.13 μM can be detected when the excitation irradiance is 3.92 mW/cm2 at an exposure time of 10 ms. PMID:25136502

  18. Space-variant restoration of images degraded by camera motion blur.

    PubMed

    Sorel, Michal; Flusser, Jan

    2008-02-01

    We examine the problem of restoration from multiple images degraded by camera motion blur. We consider scenes with significant depth variations resulting in space-variant blur. The proposed algorithm can be applied if the camera moves along an arbitrary curve parallel to the image plane, without any rotations. The knowledge of camera trajectory and camera parameters is not necessary. At the input, the user selects a region where depth variations are negligible. The algorithm belongs to the group of variational methods that estimate simultaneously a sharp image and a depth map, based on the minimization of a cost functional. To initialize the minimization, it uses an auxiliary window-based depth estimation algorithm. Feasibility of the algorithm is demonstrated by three experiments with real images. PMID:18270103

  19. New opportunities for quality enhancing of images captured by passive THz camera

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Trofimov, Vladislav V.

    2014-10-01

    As it is well-known, the passive THz camera allows seeing concealed object without contact with a person and this camera is non-dangerous for a person. Obviously, efficiency of using the passive THz camera depends on its temperature resolution. This characteristic specifies possibilities of the detection for concealed object: minimal size of the object; maximal distance of the detection; image quality. Computer processing of the THz image may lead to many times improving of the image quality without any additional engineering efforts. Therefore, developing of modern computer code for its application to THz images is urgent problem. Using appropriate new methods one may expect such temperature resolution which will allow to see banknote in pocket of a person without any real contact. Modern algorithms for computer processing of THz images allow also to see object inside the human body using a temperature trace on the human skin. This circumstance enhances essentially opportunity of passive THz camera applications for counterterrorism problems. We demonstrate opportunities, achieved at present time, for the detection both of concealed objects and of clothes components due to using of computer processing of images captured by passive THz cameras, manufactured by various companies. Another important result discussed in the paper consists in observation of both THz radiation emitted by incandescent lamp and image reflected from ceramic floorplate. We consider images produced by THz passive cameras manufactured by Microsemi Corp., and ThruVision Corp., and Capital Normal University (Beijing, China). All algorithms for computer processing of the THz images under consideration in this paper were developed by Russian part of author list. Keywords: THz wave, passive imaging camera, computer processing, security screening, concealed and forbidden objects, reflected image, hand seeing, banknote seeing, ceramic floorplate, incandescent lamp.

  20. Image Intensifier Modules For Use With Commercially Available Solid State Cameras

    NASA Astrophysics Data System (ADS)

    Murphy, Howard; Tyler, Al; Lake, Donald W.

    1989-04-01

    A modular approach to design has contributed greatly to the success of the family of machine vision video equipment produced by EG&G Reticon during the past several years. Internal modularity allows high-performance area (matrix) and line scan cameras to be assembled with two or three electronic subassemblies with very low labor costs, and permits camera control and interface circuitry to be realized by assemblages of various modules suiting the needs of specific applications. Product modularity benefits equipment users in several ways. Modular matrix and line scan cameras are available in identical enclosures (Fig. 1), which allows enclosure components to be purchased in volume for economies of scale and allows field replacement or exchange of cameras within a customer-designed system to be easily accomplished. The cameras are optically aligned (boresighted) at final test; modularity permits optical adjustments to be made with the same precise test equipment for all camera varieties. The modular cameras contain two, or sometimes three, hybrid microelectronic packages (Fig. 2). These rugged and reliable "submodules" perform all of the electronic operations internal to the camera except for the job of image acquisition performed by the monolithic image sensor. Heat produced by electrical power dissipation in the electronic modules is conducted through low resistance paths to the camera case by the metal plates, which results in a thermally efficient and environmentally tolerant camera with low manufacturing costs. A modular approach has also been followed in design of the camera control, video processor, and computer interface accessory called the Formatter (Fig. 3). This unit can be attached directly onto either a line scan or matrix modular camera to form a self-contained units, or connected via a cable to retain the advantages inherent to a small, light weight, and rugged image sensing component. Available modules permit the bus-structured Formatter to be

  1. Application of single-image camera calibration for ultrasound augmented laparoscopic visualization

    NASA Astrophysics Data System (ADS)

    Liu, Xinyang; Su, He; Kang, Sukryool; Kane, Timothy D.; Shekhar, Raj

    2015-03-01

    Accurate calibration of laparoscopic cameras is essential for enabling many surgical visualization and navigation technologies such as the ultrasound-augmented visualization system that we have developed for laparoscopic surgery. In addition to accuracy and robustness, there is a practical need for a fast and easy camera calibration method that can be performed on demand in the operating room (OR). Conventional camera calibration methods are not suitable for the OR use because they are lengthy and tedious. They require acquisition of multiple images of a target pattern in its entirety to produce satisfactory result. In this work, we evaluated the performance of a single-image camera calibration tool (rdCalib; Percieve3D, Coimbra, Portugal) featuring automatic detection of corner points in the image, whether partial or complete, of a custom target pattern. Intrinsic camera parameters of a 5-mm and a 10-mm standard Stryker® laparoscopes obtained using rdCalib and the well-accepted OpenCV camera calibration method were compared. Target registration error (TRE) as a measure of camera calibration accuracy for our optical tracking-based AR system was also compared between the two calibration methods. Based on our experiments, the single-image camera calibration yields consistent and accurate results (mean TRE = 1.18 ± 0.35 mm for the 5-mm scope and mean TRE = 1.13 ± 0.32 mm for the 10-mm scope), which are comparable to the results obtained using the OpenCV method with 30 images. The new single-image camera calibration method is promising to be applied to our augmented reality visualization system for laparoscopic surgery.

  2. Myocardial Perfusion Imaging with a Solid State Camera: Simulation of a Very Low Dose Imaging Protocol

    PubMed Central

    Nakazato, Ryo; Berman, Daniel S.; Hayes, Sean W.; Fish, Mathews; Padgett, Richard; Xu, Yuan; Lemley, Mark; Baavour, Rafael; Roth, Nathaniel; Slomka, Piotr J.

    2012-01-01

    High sensitivity dedicated cardiac systems cameras provide an opportunity to lower injected doses for SPECT myocardial perfusion imaging (MPI), but the exact limits for lowering doses have not been determined. List mode data acquisition allows for reconstruction of various fractions of acquired counts, allowing a simulation of gradually lower administered dose. We aimed to determine the feasibility of very low dose MPI by exploring the minimal count level in the myocardium for accurate MPI. Methods Seventy nine patients were studied (mean body mass index 30.0 ± 6.6, range 20.2–54.0 kg/m2) who underwent 1-day standard dose 99mTc-sestamibi exercise or adenosine rest/stress MPI for clinical indications employing a Cadmium Zinc Telluride dedicated cardiac camera. Imaging time was 14-min with 803 ± 200 MBq (21.7 ± 5.4mCi) of 99mTc injected at stress. To simulate clinical scans with lower dose at that imaging time, we reframed the list-mode raw data to have count fractions of the original scan. Accordingly, 6 stress equivalent datasets were reconstructed corresponding to each fraction of the original scan. Automated QPS/QGS software was used to quantify total perfusion deficit (TPD) and ejection fraction (EF) for all 553 datasets. Minimal acceptable count was determined based on previous report with repeatability of same-day same-injection Anger camera studies. Pearson correlation coefficients and SD of differences with TPD for all scans were calculated. Results The correlations of quantitative perfusion and function analysis were excellent for both global and regional analysis on all simulated low-counts scans (all r ≥0.95, p<0.0001). Minimal acceptable count was determined to be 1.0 million counts for the left ventricular region. At this count level, SD of differences was 1.7% for TPD and 4.2% for EF. This count level would correspond to a 92.5 MBq (2.5 mCi) injected dose for the 14 min acquisition. Conclusion 1.0 million myocardial count images appear to be

  3. Application of spatial frequency response as a criterion for evaluating thermal imaging camera performance

    NASA Astrophysics Data System (ADS)

    Lock, Andrew; Amon, Francine

    2008-04-01

    Police, firefighters, and emergency medical personnel are examples of first responders that are utilizing thermal imaging cameras in a very practical way every day. However, few performance metrics have been developed to assist first responders in evaluating the performance of thermal imaging technology. This paper describes one possible metric for evaluating spatial resolution using an application of Spatial Frequency Response (SFR) calculations for thermal imaging. According to ISO 12233, the SFR is defined as the integrated area below the Modulation Transfer Function (MTF) curve derived from the discrete Fourier transform of a camera image representing a knife-edge target. This concept is modified slightly for use as a quantitative analysis of the camera's performance by integrating the area between the MTF curve and the camera's characteristic nonuniformity, or noise floor, determined at room temperature. The resulting value, which is termed the Effective SFR, can then be compared with a spatial resolution value obtained from human perception testing of task specific situations to determine the acceptability of the performance of thermal imaging cameras. The testing procedures described herein are being developed as part of a suite of tests for possible inclusion into a performance standard on thermal imaging cameras for first responders.

  4. DEFINITION OF AIRWAY COMPOSITION WITHIN GAMMA CAMERA IMAGES

    EPA Science Inventory

    The efficacies on inhaled pharmacologic drugs in the prophylaxis and treatment if airway diseases could be improved if particles were selectively directed to appropriate Sites. n the medical arena, planar gamma scintillation cameras may be employed to study factors affecting such...

  5. Be Foil "Filter Knee Imaging" NSTX Plasma with Fast Soft X-ray Camera

    SciTech Connect

    B.C. Stratton; S. von Goeler; D. Stutman; K. Tritz; L.E. Zakharov

    2005-08-08

    A fast soft x-ray (SXR) pinhole camera has been implemented on the National Spherical Torus Experiment (NSTX). This paper presents observations and describes the Be foil Filter Knee Imaging (FKI) technique for reconstructions of a m/n=1/1 mode on NSTX. The SXR camera has a wide-angle (28{sup o}) field of view of the plasma. The camera images nearly the entire diameter of the plasma and a comparable region in the vertical direction. SXR photons pass through a beryllium foil and are imaged by a pinhole onto a P47 scintillator deposited on a fiber optic faceplate. An electrostatic image intensifier demagnifies the visible image by 6:1 to match it to the size of the charge-coupled device (CCD) chip. A pair of lenses couples the image to the CCD chip.

  6. An image compression algorithm for a high-resolution digital still camera

    NASA Technical Reports Server (NTRS)

    Nerheim, Rosalee

    1989-01-01

    The Electronic Still Camera (ESC) project will provide for the capture and transmission of high-quality images without the use of film. The image quality will be superior to video and will approach the quality of 35mm film. The camera, which will have the same general shape and handling as a 35mm camera, will be able to send images to earth in near real-time. Images will be stored in computer memory (RAM) in removable cartridges readable by a computer. To save storage space, the image will be compressed and reconstructed at the time of viewing. Both lossless and loss-y image compression algorithms are studied, described, and compared.

  7. Lobate Scarp Modeling with Lunar Reconnaissance Orbiter Camera Digital Terrain Models

    NASA Astrophysics Data System (ADS)

    Williams, N. R.; Watters, T. R.; Pritchard, M. E.; Banks, M. E.; Bell, J. F.; Robinson, M. S.; Tran, T.

    2011-12-01

    Lobate scarps are a type of contractional tectonic landform expressed on the Moon's surface in both highlands and maria. Typically only tens of meters in relief, these linear or curvilinear topographic rises are interpreted to be low-angle thrust fault scarps resulting from global radial contraction. Radial contraction of the Moon can be inferred from shortening across the population of lobate scarps and is estimated at ~100 m. However, the geometry and depth of the underlying faults and mechanical properties of the near-surface lunar crustal materials are not well constrained. The Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Cameras (NACs) acquire 0.5 to 2.0 m/pixel panchromatic images and digital terrain models (DTMs) with spatial resolutions of 2 m are derived from NAC stereo pairs. Topographic data are being used to constrain models of the lobate scarp thrust faults. DTMs are analyzed for relief and morphology of the Slipher (48.3°N, 160.6°E), Racah X-1 (10°S, 178°E), and Simpelius-1 (73.5°S, 13°E) scarps. Profiles are extracted, detrended, and compared along strike. LROC Wide Angle Camera (WAC) 100 m/pixel image mosaics and topography provide regional contexts. Using elastic dislocation modeling, the fault dip angles, depths, slip, and taper are each varied until the predicted surface displacement best fits the DTM profiles for each lobate scarp. Preliminary best-fit dip angles vary from 30-40°, maximum fault depths extend to several hundred meters, and the amount of slip varies from 10 to 30 meters for the three scarps. The modeled maximum depths suggest that the thrust faults are not deeply rooted.

  8. Temperature resolution enhancing of commercially available THz passive cameras due to computer processing of images

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Trofimov, Vladislav V.; Kuchik, Igor E.

    2014-06-01

    As it is well-known, application of the passive THz camera for the security problems is very promising way. It allows seeing concealed object without contact with a person and this camera is non-dangerous for a person. Efficiency of using the passive THz camera depends on its temperature resolution. This characteristic specifies possibilities of the detection of concealed object: minimal size of the object, maximal distance of the detection, image detail. One of probable ways for a quality image enhancing consists in computer processing of image. Using computer processing of the THz image of objects concealed on the human body, one may improve it many times. Consequently, the instrumental resolution of such device may be increased without any additional engineering efforts. We demonstrate new possibilities for seeing the clothes details, which raw images, produced by the THz cameras, do not allow to see. We achieve good quality of the image due to applying various spatial filters with the aim to demonstrate independence of processed images on math operations. This result demonstrates a feasibility of objects seeing. We consider images produced by THz passive cameras manufactured by Microsemi Corp., and ThruVision Corp., and Capital Normal University (Beijing, China).

  9. UCXp camera imaging principle and key technologies of data post-processing

    NASA Astrophysics Data System (ADS)

    Yuan, Fangyan; Li, Guoqing; Zuo, Zhengli; Liu, Jianmin; Wu, Liang; Yu, Xiaoping; Zhao, Haitao

    2014-03-01

    The large format digital aerial camera product UCXp was introduced into the Chinese market in 2008, the image consists of 17310 columns and 11310 rows with a pixel size of 6 mm. The UCXp camera has many advantages compared with the same generation camera, with multiple lenses exposed almost at the same time and no oblique lens. The camera has a complex imaging process whose principle will be detailed in this paper. On the other hand, the UCXp image post-processing method, including data pre-processing and orthophoto production, will be emphasized in this article. Based on the data of new Beichuan County, this paper will describe the data processing and effects.

  10. Super-resolved all-refocused image with a plenoptic camera

    NASA Astrophysics Data System (ADS)

    Wang, Xiang; Li, Lin; Hou, Guangqi

    2015-12-01

    This paper proposes an approach to produce the super-resolution all-refocused images with the plenoptic camera. The plenoptic camera can be produced by putting a micro-lens array between the lens and the sensor in a conventional camera. This kind of camera captures both the angular and spatial information of the scene in one single shot. A sequence of digital refocused images, which are refocused at different depth, can be produced after processing the 4D light field captured by the plenoptic camera. The number of the pixels in the refocused image is the same as that of the micro-lens in the micro-lens array. Limited number of the micro-lens will result in poor low resolution refocused images. Therefore, not enough details will exist in these images. Such lost details, which are often high frequency information, are important for the in-focus part in the refocused image. We decide to super-resolve these in-focus parts. The result of image segmentation method based on random walks, which works on the depth map produced from the 4D light field data, is used to separate the foreground and background in the refocused image. And focusing evaluation function is employed to determine which refocused image owns the clearest foreground part and which one owns the clearest background part. Subsequently, we employ single image super-resolution method based on sparse signal representation to process the focusing parts in these selected refocused images. Eventually, we can obtain the super-resolved all-focus image through merging the focusing background part and the focusing foreground part in the way of digital signal processing. And more spatial details will be kept in these output images. Our method will enhance the resolution of the refocused image, and just the refocused images owning the clearest foreground and background need to be super-resolved.

  11. Matching Images to Models: Camera Calibration for 3-D Surface Reconstruction

    NASA Technical Reports Server (NTRS)

    Morris, Robin D.; Smelyanskiy, Vadim N.; Cheeseman. Peter C.; Norvig, Peter (Technical Monitor)

    2001-01-01

    In a previous paper we described a system which recursively recovers a super-resolved three dimensional surface model from a set of images of the surface. In that paper we assumed that the camera calibration for each image was known. In this paper we solve two problems. Firstly, if an estimate of the surface is already known, the problem is to calibrate a new image relative to the existing surface model. Secondly, if no surface estimate is available, the relative camera calibration between the images in the set must be estimated. This will allow an initial surface model to be estimated. Results of both types of estimation are given.

  12. Evaluation of detector material and radiation source position on Compton camera's ability for multitracer imaging.

    PubMed

    Uche, C Z; Round, W H; Cree, M J

    2012-09-01

    We present a study on the effects of detector material, radionuclide source and source position on the Compton camera aimed at realistic characterization of the camera's performance in multitracer imaging as it relates to brain imaging. The GEANT4 Monte Carlo simulation software was used to model the physics of radiation transport and interactions with matter. Silicon (Si) and germanium (Ge) detectors were evaluated for the scatterer, and cadmium zinc telluride (CZT) and cerium-doped lanthanum bromide (LaBr(3):Ce) were considered for the absorber. Image quality analyses suggest that the use of Si as the scatterer and CZT as the absorber would be preferred. Nevertheless, two simulated Compton camera models (Si/CZT and Si/LaBr(3):Ce Compton cameras) that are considered in this study demonstrated good capabilities for multitracer imaging in that four radiotracers within the nuclear medicine energy range are clearly visualized by the cameras. It is found however that beyond a range difference of about 2 cm for (113m)In and (18)F radiotracers in a brain phantom, there may be a need to rotate the Compton camera for efficient brain imaging. PMID:22829298

  13. In-plane displacement and strain measurements using a camera phone and digital image correlation

    NASA Astrophysics Data System (ADS)

    Yu, Liping; Pan, Bing

    2014-05-01

    In-plane displacement and strain measurements of planar objects by processing the digital images captured by a camera phone using digital image correlation (DIC) are performed in this paper. As a convenient communication tool for everyday use, the principal advantages of a camera phone are its low cost, easy accessibility, and compactness. However, when used as a two-dimensional DIC system for mechanical metrology, the assumed imaging model of a camera phone may be slightly altered during the measurement process due to camera misalignment, imperfect loading, sample deformation, and temperature variations of the camera phone, which can produce appreciable errors in the measured displacements. In order to obtain accurate DIC measurements using a camera phone, the virtual displacements caused by these issues are first identified using an unstrained compensating specimen and then corrected by means of a parametric model. The proposed technique is first verified using in-plane translation and out-of-plane translation tests. Then, it is validated through a determination of the tensile strains and elastic properties of an aluminum specimen. Results of the present study show that accurate DIC measurements can be conducted using a common camera phone provided that an adequate correction is employed.

  14. Advanced camera image data acquisition system for Pi-of-the-Sky

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, Maciej; Kasprowicz, Grzegorz; Pozniak, Krzysztof; Romaniuk, Ryszard; Wrochna, Grzegorz

    2008-11-01

    The paper describes a new generation of high performance, remote control, CCD cameras designed for astronomical applications. A completely new camera PCB was designed, manufactured, tested and commissioned. The CCD chip was positioned in a different way than previously resulting in better performance of the astronomical video data acquisition system. The camera was built using a low-noise, 4Mpixel CCD circuit by STA. The electronic circuit of the camera is highly parameterized and reconfigurable, as well as modular in comparison with the solution of first generation, due to application of open software solutions and FPGA circuit, Altera Cyclone EP1C6. New algorithms were implemented into the FPGA chip. There were used the following advanced electronic circuit in the camera system: microcontroller CY7C68013a (core 8051) by Cypress, image processor AD9826 by Analog Devices, GigEth interface RTL8169s by Realtec, memory SDRAM AT45DB642 by Atmel, CPU typr microprocessor ARM926EJ-S AT91SAM9260 by ARM and Atmel. Software solutions for the camera and its remote control, as well as image data acquisition are based only on the open source platform. There were used the following image interfaces ISI and API V4L2, data bus AMBA, AHB, INDI protocol. The camera will be replicated in 20 pieces and is designed for continuous on-line, wide angle observations of the sky in the research program Pi-of-the-Sky.

  15. A Compton camera prototype for prompt gamma medical imaging

    NASA Astrophysics Data System (ADS)

    Thirolf, P. G.; Aldawood, S.; Böhmer, M.; Bortfeldt, J.; Castelhano, I.; Dedes, G.; Fiedler, F.; Gernhäuser, R.; Golnik, C.; Helmbrecht, S.; Hueso-González, F.; Kolff, H. v. d.; Kormoll, T.; Lang, C.; Liprandi, S.; Lutter, R.; Marinšek, T.; Maier, L.; Pausch, G.; Petzoldt, J.; Römer, K.; Schaart, D.; Parodi, K.

    2016-05-01

    Compton camera prototype for a position-sensitive detection of prompt γ rays from proton-induced nuclear reactions is being developed in Garching. The detector system allows to track the Comptonscattered electrons. The camera consists of a monolithic LaBr3:Ce scintillation absorber crystal, read out by a multi-anode PMT, preceded by a stacked array of 6 double-sided silicon strip detectors acting as scatterers. The LaBr3:Ce crystal has been characterized with radioactive sources. Online commissioning measurements were performed with a pulsed deuteron beam at the Garching Tandem accelerator and with a clinical proton beam at the OncoRay facility in Dresden. The determination of the interaction point of the photons in the monolithic crystal was investigated.

  16. Image dynamic range test and evaluation of Gaofen-2 dual cameras

    NASA Astrophysics Data System (ADS)

    Zhang, Zhenhua; Gan, Fuping; Wei, Dandan

    2015-12-01

    In order to fully understand the dynamic range of Gaofen-2 satellite data and support the data processing, application and next satellites development, in this article, we evaluated the dynamic range by calculating some statistics such as maximum ,minimum, average and stand deviation of four images obtained at the same time by Gaofen-2 dual cameras in Beijing area; then the maximum ,minimum, average and stand deviation of each longitudinal overlap of PMS1,PMS2 were calculated respectively for the evaluation of each camera's dynamic range consistency; and these four statistics of each latitudinal overlap of PMS1,PMS2 were calculated respectively for the evaluation of the dynamic range consistency between PMS1 and PMS2 at last. The results suggest that there is a wide dynamic range of DN value in the image obtained by PMS1 and PMS2 which contains rich information of ground objects; in general, the consistency of dynamic range between the single camera images is in close agreement, but also a little difference, so do the dual cameras. The consistency of dynamic range between the single camera images is better than the dual cameras'.

  17. Hybrid Compton camera/coded aperture imaging system

    DOEpatents

    Mihailescu, Lucian; Vetter, Kai M.

    2012-04-10

    A system in one embodiment includes an array of radiation detectors; and an array of imagers positioned behind the array of detectors relative to an expected trajectory of incoming radiation. A method in another embodiment includes detecting incoming radiation with an array of radiation detectors; detecting the incoming radiation with an array of imagers positioned behind the array of detectors relative to a trajectory of the incoming radiation; and performing at least one of Compton imaging using at least the imagers and coded aperture imaging using at least the imagers. A method in yet another embodiment includes detecting incoming radiation with an array of imagers positioned behind an array of detectors relative to a trajectory of the incoming radiation; and performing Compton imaging using at least the imagers.

  18. Exploring the feasibility of iris recognition for visible spectrum iris images obtained using smartphone camera

    NASA Astrophysics Data System (ADS)

    Trokielewicz, Mateusz; Bartuzi, Ewelina; Michowska, Katarzyna; Andrzejewska, Antonina; Selegrat, Monika

    2015-09-01

    In the age of modern, hyperconnected society that increasingly relies on mobile devices and solutions, implementing a reliable and accurate biometric system employing iris recognition presents new challenges. Typical biometric systems employing iris analysis require expensive and complicated hardware. We therefore explore an alternative way using visible spectrum iris imaging. This paper aims at answering several questions related to applying iris biometrics for images obtained in the visible spectrum using smartphone camera. Can irides be successfully and effortlessly imaged using a smartphone's built-in camera? Can existing iris recognition methods perform well when presented with such images? The main advantage of using near-infrared (NIR) illumination in dedicated iris recognition cameras is good performance almost independent of the iris color and pigmentation. Are the images obtained from smartphone's camera of sufficient quality even for the dark irides? We present experiments incorporating simple image preprocessing to find the best visibility of iris texture, followed by a performance study to assess whether iris recognition methods originally aimed at NIR iris images perform well with visible light images. To our best knowledge this is the first comprehensive analysis of iris recognition performance using a database of high-quality images collected in visible light using the smartphones flashlight together with the application of commercial off-the-shelf (COTS) iris recognition methods.

  19. High-frame-rate intensified fast optically shuttered TV cameras with selected imaging applications

    SciTech Connect

    Yates, G.J.; King, N.S.P.

    1994-08-01

    This invited paper focuses on high speed electronic/electro-optic camera development by the Applied Physics Experiments and Imaging Measurements Group (P-15) of Los Alamos National Laboratory`s Physics Division over the last two decades. The evolution of TV and image intensifier sensors and fast readout fast shuttered cameras are discussed. Their use in nuclear, military, and medical imaging applications are presented. Several salient characteristics and anomalies associated with single-pulse and high repetition rate performance of the cameras/sensors are included from earlier studies to emphasize their effects on radiometric accuracy of electronic framing cameras. The Group`s test and evaluation capabilities for characterization of imaging type electro-optic sensors and sensor components including Focal Plane Arrays, gated Image Intensifiers, microchannel plates, and phosphors are discussed. Two new unique facilities, the High Speed Solid State Imager Test Station (HSTS) and the Electron Gun Vacuum Test Chamber (EGTC) arc described. A summary of the Group`s current and developmental camera designs and R&D initiatives are included.

  20. Design Considerations Of A Compton Camera For Low Energy Medical Imaging

    SciTech Connect

    Harkness, L. J.; Boston, A. J.; Boston, H. C.; Cresswell, J. R.; Grint, A. N.; Judson, D. S.; Nolan, P. J.; Oxley, D. C.; Lazarus, I.; Simpson, J.

    2009-12-02

    Development of a Compton camera for low energy medical imaging applications is underway. The ProSPECTus project aims to utilize position sensitive detectors to generate high quality images using electronic collimation. This method has the potential to significantly increase the imaging efficiency compared with mechanically collimated SPECT systems, a highly desirable improvement on clinical systems. Design considerations encompass the geometrical optimisation and evaluation of image quality from the system which is to be built and assessed.

  1. Robust real time extraction of plane segments from time-of-flight camera images

    NASA Astrophysics Data System (ADS)

    Dalbah, Yosef; Koltermann, Dirk; Wahl, Friedrich M.

    2014-04-01

    We present a method that extracts plane segments from images of a time-of-flight camera. Future driver assistance systems rely on an accurate description of the vehicle's environment. Time-of-flight cameras can be used for environment perception and for the reconstruction of the environment. Since most structures in urban environments are planar, extracted plane segments from single camera images can be used for the creation of a global map. We present a method for real time detection of planar surface structures from time-of-flight camera data. The concept is based on a planar surface segmentation that serves as the fundament for a subsequent global planar surface extraction. The evaluation demonstrates the ability of the described algorithm to detect planar surfaces form depth data of complex scenarios in real time. We compare our methods to state of the art planar surface extraction algorithms.

  2. Perspective Intensity Images for Co-Registration of Terrestrial Laser Scanner and Digital Camera

    NASA Astrophysics Data System (ADS)

    Liang, Yubin; Qiu, Yan; Cui, Tiejun

    2016-06-01

    Co-registration of terrestrial laser scanner and digital camera has been an important topic of research, since reconstruction of visually appealing and measurable models of the scanned objects can be achieved by using both point clouds and digital images. This paper presents an approach for co-registration of terrestrial laser scanner and digital camera. A perspective intensity image of the point cloud is firstly generated by using the collinearity equation. Then corner points are extracted from the generated perspective intensity image and the camera image. The fundamental matrix F is then estimated using several interactively selected tie points and used to obtain more matches with RANSAC. The 3D coordinates of all the matched tie points are directly obtained or estimated using the least squares method. The robustness and effectiveness of the presented methodology is demonstrated by the experimental results. Methods presented in this work may also be used for automatic registration of terrestrial laser scanning point clouds.

  3. The Mast Cameras and Mars Descent Imager (MARDI) for the 2009 Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Malin, M. C.; Bell, J. F.; Cameron, J.; Dietrich, W. E.; Edgett, K. S.; Hallet, B.; Herkenhoff, K. E.; Lemmon, M. T.; Parker, T. J.; Sullivan, R. J.

    2005-01-01

    Based on operational experience gained during the Mars Exploration Rover (MER) mission, we proposed and were selected to conduct two related imaging experiments: (1) an investigation of the geology and short-term atmospheric vertical wind profile local to the Mars Science Laboratory (MSL) landing site using descent imaging, and (2) a broadly-based scientific investigation of the MSL locale employing visible and very near infra-red imaging techniques from a pair of mast-mounted, high resolution cameras. Both instruments share a common electronics design, a design also employed for the MSL Mars Hand Lens Imager (MAHLI) [1]. The primary differences between the cameras are in the nature and number of mechanisms and specific optics tailored to each camera s requirements.

  4. Microchannel plate pinhole camera for 20 to 100 keV x-ray imaging

    SciTech Connect

    Wang, C.L.; Leipelt, G.R.; Nilson, D.G.

    1984-10-03

    We present the design and construction of a sensitive pinhole camera for imaging suprathermal x-rays. Our device is a pinhole camera consisting of four filtered pinholes and microchannel plate electron multiplier for x-ray detection and signal amplification. We report successful imaging of 20, 45, 70, and 100 keV x-ray emissions from the fusion targets at our Novette laser facility. Such imaging reveals features of the transport of hot electrons and provides views deep inside the target.

  5. A Compton camera for spectroscopic imaging from 100 keV to 1 MeV

    SciTech Connect

    Earnhart, J.R.D.

    1998-12-31

    A review of spectroscopic imaging issues, applications, and technology is presented. Compton cameras based on solid state semiconductor detectors stands out as the best system for the nondestructive assay of special nuclear materials. A camera for this application has been designed based on an efficient specific purpose Monte Carlo code developed for this project. Preliminary experiments have been performed which demonstrate the validity of the Compton camera concept and the accuracy of the code. Based on these results, a portable prototype system is in development. Proposed future work is addressed.

  6. A high-resolution airborne four-camera imaging system for agricultural remote sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the design and testing of an airborne multispectral digital imaging system for remote sensing applications. The system consists of four high resolution charge coupled device (CCD) digital cameras and a ruggedized PC equipped with a frame grabber and image acquisition software. T...

  7. Imaging of breast cancer with mid- and long-wave infrared camera.

    PubMed

    Joro, R; Lääperi, A-L; Dastidar, P; Soimakallio, S; Kuukasjärvi, T; Toivonen, T; Saaristo, R; Järvenpää, R

    2008-01-01

    In this novel study the breasts of 15 women with palpable breast cancer were preoperatively imaged with three technically different infrared (IR) cameras - micro bolometer (MB), quantum well (QWIP) and photo voltaic (PV) - to compare their ability to differentiate breast cancer from normal tissue. The IR images were processed, the data for frequency analysis were collected from dynamic IR images by pixel-based analysis and from each image selectively windowed regional analysis was carried out, based on angiogenesis and nitric oxide production of cancer tissue causing vasomotor and cardiogenic frequency differences compared to normal tissue. Our results show that the GaAs QWIP camera and the InSb PV camera demonstrate the frequency difference between normal and cancerous breast tissue; the PV camera more clearly. With selected image processing operations more detailed frequency analyses could be applied to the suspicious area. The MB camera was not suitable for tissue differentiation, as the difference between noise and effective signal was unsatisfactory. PMID:18432466

  8. Constructing a Database from Multiple 2D Images for Camera Pose Estimation and Robot Localization

    NASA Technical Reports Server (NTRS)

    Wolf, Michael; Ansar, Adnan I.; Brennan, Shane; Clouse, Daniel S.; Padgett, Curtis W.

    2012-01-01

    The LMDB (Landmark Database) Builder software identifies persistent image features (landmarks) in a scene viewed multiple times and precisely estimates the landmarks 3D world positions. The software receives as input multiple 2D images of approximately the same scene, along with an initial guess of the camera poses for each image, and a table of features matched pair-wise in each frame. LMDB Builder aggregates landmarks across an arbitrarily large collection of frames with matched features. Range data from stereo vision processing can also be passed to improve the initial guess of the 3D point estimates. The LMDB Builder aggregates feature lists across all frames, manages the process to promote selected features to landmarks, and iteratively calculates the 3D landmark positions using the current camera pose estimations (via an optimal ray projection method), and then improves the camera pose estimates using the 3D landmark positions. Finally, it extracts image patches for each landmark from auto-selected key frames and constructs the landmark database. The landmark database can then be used to estimate future camera poses (and therefore localize a robotic vehicle that may be carrying the cameras) by matching current imagery to landmark database image patches and using the known 3D landmark positions to estimate the current pose.

  9. The Geospectral Camera: a Compact and Geometrically Precise Hyperspectral and High Spatial Resolution Imager

    NASA Astrophysics Data System (ADS)

    Delauré, B.; Michiels, B.; Biesemans, J.; Livens, S.; Van Achteren, T.

    2013-04-01

    Small unmanned aerial vehicles are increasingly being employed for environmental monitoring at local scale, which drives the demand for compact and lightweight spectral imagers. This paper describes the geospectral camera, which is a novel compact imager concept. The camera is built around an innovative detector which has two sensor elements on a single chip and therefore offers the functionality of two cameras within the volume of a single one. The two sensor elements allow the camera to derive both spectral information as well as geometric information (high spatial resolution imagery and a digital surface model) of the scene of interest. A first geospectral camera prototype has been developed. It uses a linear variable optical filter which is installed in front of one of the two sensors of the MEDUSA CMOS imager chip. A accompanying software approach has been developed which exploits the simultaneous information of the two sensors in order to extract an accurate spectral image product. This method has been functionally demonstrated by applying it on image data acquired during an airborne acquisition.

  10. Intial synchroscan streak camera imaging at the A0 photoinjector

    SciTech Connect

    Lumpkin, A.H.; Ruan, J.; /Fermilab

    2008-04-01

    At the Fermilab A0 photoinjector facility, bunch-length measurements of the laser micropulse and the e-beam micropulse have been done in the past with a single-sweep module of the Hamamatsu C5680 streak camera with an intrinsic shot-to-shot trigger jitter of 10 to 20 ps. We have upgraded the camera system with the synchroscan module tuned to 81.25 MHz to provide synchronous summing capability with less than 1.5-ps FWHM trigger jitter and a phase-locked delay box to provide phase stability of {approx}1 ps over 10s of minutes. This allowed us to measure both the UV laser pulse train at 244 nm and the e-beam via optical transition radiation (OTR). Due to the low electron beam energies and OTR signals, we typically summed over 50 micropulses with 1 nC per micropulse. We also did electron beam bunch length vs. micropulse charge measurements to identify a significant e-beam micropulse elongation from 10 to 30 ps (FWHM) for charges from 1 to 4.6 nC. This effect is attributed to space-charge effects in the PC gun as reproduced by ASTRA calculations. Chromatic temporal dispersion effects in the optics were also characterized and will be reported.

  11. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    SciTech Connect

    Medley, S.S.; Dimock, D.L.; Hayes, S.; Long, D.; Lowrance, J.L.; Mastrocola, V.; Renda, G.; Ulrickson, M.; Young, K.M.

    1985-10-01

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect the vacuum vessel internal structures in both the visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diam fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (5/sup 0/, 20/sup 0/, and 60/sup 0/ field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35-mm Nikon F3 still camera, or (5) a 16-mm Locam II movie camera with variable framing rate up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented.

  12. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    SciTech Connect

    Medley, S.S.; Dimock, D.L.; Hayes, S.; Long, D.; Lowrence, J.L.; Mastrocola, V.; Renda, G.; Ulrickson, M.; Young, K.M.

    1985-05-01

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diameter fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (5/sup 0/, 20/sup 0/, and 60/sup 0/ field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35 mm Nikon F3 still camera, or (5) a 16 mm Locam II movie camera with variable framing up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented.

  13. Review of the characteristics of 384x288 pixel THz camera for see-through imaging

    NASA Astrophysics Data System (ADS)

    Marchese, Linda; Terroux, Marc; Genereux, Francis; Tremblay, Bruno; Bolduc, Martin; Bergeron, Alain

    2013-10-01

    Terahertz is a field in constant expansion. Multiple applications are foreseen including see-through imaging. To develop deployable systems, real-time two-dimensional cameras are needed rather than monopixel detectors or linear arrays that require mechanical scanning systems. INO has recently developed a real-time (video rate) 384x288 THz camera exhibiting excellent sensitivity and low noise levels. The core of the THz imager is the 35 μm pitch detector array that is based on INO's uncooled VOx microbolometer technology and fabricated in INO's clean room. A standard ceramic package is used for final packaging. The detector FPA is finally sealed with a high resistivity float zone silicon (HRFZ-Si) window having an anti-reflective coating consisting of thick Parylene, which the thickness of which depends on the required optimization wavelength. The FPA is mounted on an INO IRXCAM core giving a passive THz camera assembly. The additional THz objective consists of a refractive 44 mm focal length F/1 THz lens. In this paper, a review of the characteristics of the THz camera at is performed. The sensitivity of the camera at various THz wavelengths is presented along with examples of the resolution obtained with the IRXCAM-384-THz camera core. See-through imaging results are also presented.

  14. Precise color images a high-speed color video camera system with three intensified sensors

    NASA Astrophysics Data System (ADS)

    Oki, Sachio; Yamakawa, Masafumi; Gohda, Susumu; Etoh, Takeharu G.

    1999-06-01

    High speed imaging systems have been used in a large field of science and engineering. Although the high speed camera systems have been improved to high performance, most of their applications are only to get high speed motion pictures. However, in some fields of science and technology, it is useful to get some other information, such as temperature of combustion flame, thermal plasma and molten materials. Recent digital high speed video imaging technology should be able to get such information from those objects. For this purpose, we have already developed a high speed video camera system with three-intensified-sensors and cubic prism image splitter. The maximum frame rate is 40,500 pps (picture per second) at 64 X 64 pixels and 4,500 pps at 256 X 256 pixels with 256 (8 bit) intensity resolution for each pixel. The camera system can store more than 1,000 pictures continuously in solid state memory. In order to get the precise color images from this camera system, we need to develop a digital technique, which consists of a computer program and ancillary instruments, to adjust displacement of images taken from two or three image sensors and to calibrate relationship between incident light intensity and corresponding digital output signals. In this paper, the digital technique for pixel-based displacement adjustment are proposed. Although the displacement of the corresponding circle was more than 8 pixels in original image, the displacement was adjusted within 0.2 pixels at most by this method.

  15. Demonstration of three-dimensional imaging based on handheld Compton camera

    NASA Astrophysics Data System (ADS)

    Kishimoto, A.; Kataoka, J.; Nishiyama, T.; Taya, T.; Kabuki, S.

    2015-11-01

    Compton cameras are potential detectors that are capable of performing measurements across a wide energy range for medical imaging applications, such as in nuclear medicine and ion beam therapy. In previous work, we developed a handheld Compton camera to identify environmental radiation hotspots. This camera consists of a 3D position-sensitive scintillator array and multi-pixel photon counter arrays. In this work, we reconstructed the 3D image of a source via list-mode maximum likelihood expectation maximization and demonstrated the imaging performance of the handheld Compton camera. Based on both the simulation and the experiments, we confirmed that multi-angle data acquisition of the imaging region significantly improved the spatial resolution of the reconstructed image in the direction vertical to the detector. The experimental spatial resolutions in the X, Y, and Z directions at the center of the imaging region were 6.81 mm ± 0.13 mm, 6.52 mm ± 0.07 mm and 6.71 mm ± 0.11 mm (FWHM), respectively. Results of multi-angle data acquisition show the potential of reconstructing 3D source images.

  16. Enhancing swimming pool safety by the use of range-imaging cameras

    NASA Astrophysics Data System (ADS)

    Geerardyn, D.; Boulanger, S.; Kuijk, M.

    2015-05-01

    Drowning is the cause of death of 372.000 people, each year worldwide, according to the report of November 2014 of the World Health Organization.1 Currently, most swimming pools only use lifeguards to detect drowning people. In some modern swimming pools, camera-based detection systems are nowadays being integrated. However, these systems have to be mounted underwater, mostly as a replacement of the underwater lighting. In contrast, we are interested in range imaging cameras mounted on the ceiling of the swimming pool, allowing to distinguish swimmers at the surface from drowning people underwater, while keeping the large field-of-view and minimizing occlusions. However, we have to take into account that the water surface of a swimming pool is not a flat, but mostly rippled surface, and that the water is transparent for visible light, but less transparent for infrared or ultraviolet light. We investigated the use of different types of 3D cameras to detect objects underwater at different depths and with different amplitudes of surface perturbations. Specifically, we performed measurements with a commercial Time-of-Flight camera, a commercial structured-light depth camera and our own Time-of-Flight system. Our own system uses pulsed Time-of-Flight and emits light of 785 nm. The measured distances between the camera and the object are influenced through the perturbations on the water surface. Due to the timing of our Time-of-Flight camera, our system is theoretically able to minimize the influence of the reflections of a partially-reflecting surface. The combination of a post image-acquisition filter compensating for the perturbations and the use of a light source with shorter wavelengths to enlarge the depth range can improve the current commercial cameras. As a result, we can conclude that low-cost range imagers can increase swimming pool safety, by inserting a post-processing filter and the use of another light source.

  17. Driving micro-optical imaging systems towards miniature camera applications

    NASA Astrophysics Data System (ADS)

    Brückner, Andreas; Duparré, Jacques; Dannberg, Peter; Leitel, Robert; Bräuer, Andreas

    2010-05-01

    Up to now, multi channel imaging systems have been increasingly studied and approached from various directions in the academic domain due to their promising large field of view at small system thickness. However, specific drawbacks of each of the solutions prevented the diffusion into corresponding markets so far. Most severe problems are a low image resolution and a low sensitivity compared to a conventional single aperture lens besides the lack of a cost-efficient method of fabrication and assembly. We propose a microoptical approach to ultra-compact optics for real-time vision systems that are inspired by the compound eyes of insects. The demonstrated modules achieve a VGA resolution with 700x550 pixels within an optical package of 6.8mm x 5.2mm and a total track length of 1.4mm. The partial images that are separately recorded within different optical channels are stitched together to form a final image of the whole field of view by means of image processing. These software tools allow to correct the distortion of the individual partial images so that the final image is also free of distortion. The so-called electronic cluster eyes are realized by state-of-the-art microoptical fabrication techniques and offer a resolution and sensitivity potential that makes them suitable for consumer, machine vision and medical imaging applications.

  18. Geometric Calibration of the Orion Optical Navigation Camera using Star Field Images

    NASA Astrophysics Data System (ADS)

    Christian, John A.; Benhacine, Lylia; Hikes, Jacob; D'Souza, Christopher

    2016-07-01

    The Orion Multi Purpose Crew Vehicle will be capable of autonomously navigating in cislunar space using images of the Earth and Moon. Optical navigation systems, such as the one proposed for Orion, require the ability to precisely relate the observed location of an object in a 2D digital image with the true corresponding line-of-sight direction in the camera's sensor frame. This relationship is governed by the camera's geometric calibration parameters — typically described by a set of five intrinsic parameters and five lens distortion parameters. While pre-flight estimations of these parameters will exist, environmental conditions often necessitate on-orbit recalibration. This calibration will be performed for Orion using an ensemble of star field images. This manuscript provides a detailed treatment of the theory and mathematics that will form the foundation of Orion's on-orbit camera calibration. Numerical results and examples are also presented.

  19. Retinal axial focusing and multi-layer imaging with a liquid crystal adaptive optics camera

    NASA Astrophysics Data System (ADS)

    Liu, Rui-Xue; Zheng, Xian-Liang; Li, Da-Yu; Xia, Ming-Liang; Hu, Li-Fa; Cao, Zhao-Liang; Mu, Quan-Quan; Xuan, Li

    2014-09-01

    With the help of adaptive optics (AO) technology, cellular level imaging of living human retina can be achieved. Aiming to reduce distressing feelings and to avoid potential drug induced diseases, we attempted to image retina with dilated pupil and froze accommodation without drugs. An optimized liquid crystal adaptive optics camera was adopted for retinal imaging. A novel eye stared system was used for stimulating accommodation and fixating imaging area. Illumination sources and imaging camera kept linkage for focusing and imaging different layers. Four subjects with diverse degree of myopia were imaged. Based on the optical properties of the human eye, the eye stared system reduced the defocus to less than the typical ocular depth of focus. In this way, the illumination light can be projected on certain retina layer precisely. Since that the defocus had been compensated by the eye stared system, the adopted 512 × 512 liquid crystal spatial light modulator (LC-SLM) corrector provided the crucial spatial fidelity to fully compensate high-order aberrations. The Strehl ratio of a subject with -8 diopter myopia was improved to 0.78, which was nearly close to diffraction-limited imaging. By finely adjusting the axial displacement of illumination sources and imaging camera, cone photoreceptors, blood vessels and nerve fiber layer were clearly imaged successfully.

  20. Achieving thermography with a thermal security camera using uncooled amorphous silicon microbolometer image sensors

    NASA Astrophysics Data System (ADS)

    Wang, Yu-Wei; Tesdahl, Curtis; Owens, Jim; Dorn, David

    2012-06-01

    Advancements in uncooled microbolometer technology over the last several years have opened up many commercial applications which had been previously cost prohibitive. Thermal technology is no longer limited to the military and government market segments. One type of thermal sensor with low NETD which is available in the commercial market segment is the uncooled amorphous silicon (α-Si) microbolometer image sensor. Typical thermal security cameras focus on providing the best image quality by auto tonemaping (contrast enhancing) the image, which provides the best contrast depending on the temperature range of the scene. While this may provide enough information to detect objects and activities, there are further benefits of being able to estimate the actual object temperatures in a scene. This thermographic ability can provide functionality beyond typical security cameras by being able to monitor processes. Example applications of thermography[2] with thermal camera include: monitoring electrical circuits, industrial machinery, building thermal leaks, oil/gas pipelines, power substations, etc...[3][5] This paper discusses the methodology of estimating object temperatures by characterizing/calibrating different components inside a thermal camera utilizing an uncooled amorphous silicon microbolometer image sensor. Plots of system performance across camera operating temperatures will be shown.

  1. A novel IR polarization imaging system designed by a four-camera array

    NASA Astrophysics Data System (ADS)

    Liu, Fei; Shao, Xiaopeng; Han, Pingli

    2014-05-01

    A novel IR polarization staring imaging system employing a four-camera-array is designed for target detection and recognition, especially man-made targets hidden in complex battle field. The design bases on the existence of the difference in infrared radiation's polarization characteristics, which is particularly remarkable between artificial objects and the natural environment. The system designed employs four cameras simultaneously to capture the00 polarization difference to replace the commonly used systems engaging only one camera. Since both types of systems have to obtain intensity images in four different directions (I0 , I45 , I90 , I-45 ), the four-camera design allows better real-time capability and lower error without the mechanical rotating parts which is essential to one-camera systems. Information extraction and detailed analysis demonstrate that the caught polarization images include valuable polarization information which can effectively increase the images' contrast and make it easier to segment the target even the hidden target from various scenes.

  2. Automatic control of a robot camera for broadcasting and subjective evaluation and analysis of reproduced images

    NASA Astrophysics Data System (ADS)

    Kato, Daiichiro; Ishikawa, Akio; Tsuda, Takao; Shimoda, Shigeru; Fukushima, Hiroshi

    2000-06-01

    We are studying about an intelligent robot camera that can automatically shoot an object and produce images with a powerful sense of reality as if a very skilled cameraman were at work. In this study, we designed a control algorithm based on cameramen's techniques for the control of the robot camera and conducted a series of experiments to understand the effects of camera work on how images look to viewers. The findings were as follows: (1) Evaluation scores are high when actual data by cameraman, especially typical data, are used as the position adjusting velocity curve of the target. (2) Evaluation scores are relatively high for images taken with feedback-feedforward camera control method when the target moves in one direction. (3) When both the direction and velocity of the target change and when the target gets bigger and faster in the view finder, it becomes increasingly difficult to keep the target within the view finder using the control method that imitates the human camera handling. (4) The method with mechanical feedback, on the other hand, is able to cope with rapid changes in the target's direction and velocity, constantly keeping the target within the view finder. Even so, the viewer finds the image rather mechanical than natural.

  3. Vehicle occupancy detection camera position optimization using design of experiments and standard image references

    NASA Astrophysics Data System (ADS)

    Paul, Peter; Hoover, Martin; Rabbani, Mojgan

    2013-03-01

    Camera positioning and orientation is important to applications in domains such as transportation since the objects to be imaged vary greatly in shape and size. In a typical transportation application that requires capturing still images, inductive loops buried in the ground or laser trigger sensors are used when a vehicle reaches the image capture zone to trigger the image capture system. The camera in such a system is in a fixed position pointed at the roadway and at a fixed orientation. Thus the problem is to determine the optimal location and orientation of the camera when capturing images from a wide variety of vehicles. Methods from Design for Six Sigma, including identifying important parameters and noise sources and performing systematically designed experiments (DOE) can be used to determine an effective set of parameter settings for the camera position and orientation under these conditions. In the transportation application of high occupancy vehicle lane enforcement, the number of passengers in the vehicle is to be counted. Past work has described front seat vehicle occupant counting using a camera mounted on an overhead gantry looking through the front windshield in order to capture images of vehicle occupants. However, viewing rear seat passengers is more problematic due to obstructions including the vehicle body frame structures and seats. One approach is to view the rear seats through the side window. In this situation the problem of optimally positioning and orienting the camera to adequately capture the rear seats through the side window can be addressed through a designed experiment. In any automated traffic enforcement system it is necessary for humans to be able to review any automatically captured digital imagery in order to verify detected infractions. Thus for defining an output to be optimized for the designed experiment, a human defined standard image reference (SIR) was used to quantify the quality of the line-of-sight to the rear seats of

  4. Imaging with depth extension: where are the limits in fixed- focus cameras?

    NASA Astrophysics Data System (ADS)

    Bakin, Dmitry; Keelan, Brian

    2008-08-01

    The integration of novel optics designs, miniature CMOS sensors, and powerful digital processing into a single imaging module package is driving progress in handset camera systems in terms of performance, size (thinness) and cost. The miniature cameras incorporating high resolution sensors and fixed-focus Extended Depth of Field (EDOF) optics allow close-range reading of printed material (barcode patterns, business cards), while providing high quality imaging in more traditional applications. These cameras incorporate modified optics and digital processing to recover the soft-focus images and restore sharpness over a wide range of object distances. The effects a variety of parameters of the imaging module on the EDOF range were analyzed for a family of high resolution CMOS modules. The parameters include various optical properties of the imaging lens, and the characteristics of the sensor. The extension factors for the EDOF imaging module were defined in terms of an improved absolute resolution in object space while maintaining focus at infinity. This definition was applied for the purpose of identifying the minimally resolvable object details in mobile cameras with bar-code reading feature.

  5. Brute Force Matching Between Camera Shots and Synthetic Images from Point Clouds

    NASA Astrophysics Data System (ADS)

    Boerner, R.; Kröhnert, M.

    2016-06-01

    3D point clouds, acquired by state-of-the-art terrestrial laser scanning techniques (TLS), provide spatial information about accuracies up to several millimetres. Unfortunately, common TLS data has no spectral information about the covered scene. However, the matching of TLS data with images is important for monoplotting purposes and point cloud colouration. Well-established methods solve this issue by matching of close range images and point cloud data by fitting optical camera systems on top of laser scanners or rather using ground control points. The approach addressed in this paper aims for the matching of 2D image and 3D point cloud data from a freely moving camera within an environment covered by a large 3D point cloud, e.g. a 3D city model. The key advantage of the free movement affects augmented reality applications or real time measurements. Therefore, a so-called real image, captured by a smartphone camera, has to be matched with a so-called synthetic image which consists of reverse projected 3D point cloud data to a synthetic projection centre whose exterior orientation parameters match the parameters of the image, assuming an ideal distortion free camera.

  6. Camera motion tracking of real bronchoscope using epipolar geometry analysis and CT-derived bronchoscopic images

    NASA Astrophysics Data System (ADS)

    Deguchi, Daisuke; Mori, Kensaku; Hasegawa, Jun-ichi; Toriwaki, Jun-ichiro; Takabatake, Hirotsugu; Natori, Hiroshi

    2002-04-01

    This paper describes a method to track camera motion of a real endoscope by using epipolar geometry analysis and CT derived virtual endoscopic images. A navigation system for a flexible endoscope guides medical doctors by providing navigation information during endoscope examinations. This paper tries to estimate the motion from an endoscopic video image based on epipolar geometry analysis and image registration between virtual endoscopic (VE) and real endoscopic (RE) images. The method consists of three parts: (a) direct estimation of camera motion by using epipolar geometry analysis, (b) precise estimation by using image registration, and (c) detection of bubble frames for avoiding miss-registration. First we calculate optical flow patterns from two consecutive frames. The camera motion is computed by substituting the obtained flows into the epipolar equations. Then we find the observation parameter of a virtual endoscopy system that generates the most similar endoscopic view to the current RE frame. We execute these processes for all frames of RE videos except for frames where bubbles appear. We applied the proposed method to RE videos of three patients who have CT images. The experimental results show the method can track camera motion for over 500 frames continuously in the best case.

  7. Geopositioning Precision Analysis of Multiple Image Triangulation Using Lro Nac Lunar Images

    NASA Astrophysics Data System (ADS)

    Di, K.; Xu, B.; Liu, B.; Jia, M.; Liu, Z.

    2016-06-01

    This paper presents an empirical analysis of the geopositioning precision of multiple image triangulation using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images at the Chang'e-3(CE-3) landing site. Nine LROC NAC images are selected for comparative analysis of geopositioning precision. Rigorous sensor models of the images are established based on collinearity equations with interior and exterior orientation elements retrieved from the corresponding SPICE kernels. Rational polynomial coefficients (RPCs) of each image are derived by least squares fitting using vast number of virtual control points generated according to rigorous sensor models. Experiments of different combinations of images are performed for comparisons. The results demonstrate that the plane coordinates can achieve a precision of 0.54 m to 2.54 m, with a height precision of 0.71 m to 8.16 m when only two images are used for three-dimensional triangulation. There is a general trend that the geopositioning precision, especially the height precision, is improved with the convergent angle of the two images increasing from several degrees to about 50°. However, the image matching precision should also be taken into consideration when choosing image pairs for triangulation. The precisions of using all the 9 images are 0.60 m, 0.50 m, 1.23 m in along-track, cross-track, and height directions, which are better than most combinations of two or more images. However, triangulation with selected fewer images could produce better precision than that using all the images.

  8. One high-accuracy camera calibration algorithm based on computer vision images

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Huang, Jianming; Wei, Xiangquan

    2015-12-01

    Camera calibration is the first step of computer vision and one of the most active research fields nowadays. In order to improve the measurement precision, the internal parameters of the camera should be accurately calibrated. So one high-accuracy camera calibration algorithm is proposed based on the images of planar targets or tridimensional targets. By using the algorithm, the internal parameters of the camera are calibrated based on the existing planar target at the vision-based navigation experiment. The experimental results show that the accuracy of the proposed algorithm is obviously improved compared with the conventional linear algorithm, Tsai general algorithm, and Zhang Zhengyou calibration algorithm. The algorithm proposed by the article can satisfy the need of computer vision and provide reference for precise measurement of the relative position and attitude.

  9. Development of a handheld fluorescence imaging camera for intraoperative sentinel lymph node mapping

    NASA Astrophysics Data System (ADS)

    Szyc, Łukasz; Bonifer, Stefanie; Walter, Alfred; Jagemann, Uwe; Grosenick, Dirk; Macdonald, Rainer

    2015-05-01

    We present a compact fluorescence imaging system developed for real-time sentinel lymph node mapping. The device uses two near-infrared wavelengths to record fluorescence and anatomical images with a single charge-coupled device camera. Experiments on lymph node and tissue phantoms confirmed that the amount of dye in superficial lymph nodes can be better estimated due to the absorption correction procedure integrated in our device. Because of the camera head's small size and low weight, all accessible regions of tissue can be reached without the need for any adjustments.

  10. CAMAC interface for digitally recording infrared camera images

    NASA Astrophysics Data System (ADS)

    Dyer, G. R.

    1986-06-01

    An instrument has been built to store the digital signals from a modified imaging infrared scanner directly in a digital memory. This procedure avoids the signal-to-noise degradation and dynamic range limitations associated with successive analog-to-digital and digital-to-analog conversions and the analog recording method normally used to store data from the scanner. This technique also allows digital data processing methods to be applied directly to recorded data and permits processing and image reconstruction to be done using either a mainframe or a microcomputer. If a suitable computer and CAMAC-based data collection system are already available, digital storage of up to 12 scanner images can be implemented for less than 1750 in materials cost. Each image is stored as a frame of 60×80 eight-bit pixels, with an acquisition rate of one frame every 16.7 ms. The number of frames stored is limited only by the available memory. Initially, data processing for this equipment was done on a VAX 11-780, but images may also be displayed on the screen of a microcomputer. Software for setting the displayed gray scale, generating contour plots and false-color displays, and subtracting one image from another (e.g., background suppression) has been developed for IBM-compatible personal computers.

  11. A review of small animal imaging planar and pinhole spect Gamma camera imaging.

    PubMed

    Peremans, Kathelijne; Cornelissen, Bart; Van Den Bossche, Bieke; Audenaert, Kurt; Van de Wiele, Christophe

    2005-01-01

    Scintigraphy (positron emission tomography (PET) or single photon emission computed tomography (SPECT) techniques) allows qualitative and quantitative measurement of physiologic processes as well as alterations secondary to various disease states. With the use of specific radioligands, molecular pathways and pharmaco-kinetic processes can be investigated. Radioligand delivery can be (semi)quantified in the region of interest in cross-sectional and longitudinal examinations, which can be performed under the same conditions or after physiologic or pharmacologic interventions. Most preclinical pharmacokinetic studies on physiological and experimentally altered physiological processes are performed in laboratory animals using high-resolution imaging systems. Single photon emission imaging has the disadvantage of decreased spatial and temporal resolution compared with PET. The advantage of SPECT is that equipment is generally more accessible and commonly used radionuclides have a longer physical half-life allowing for investigations over a longer time interval. This review will focus on single photon emission scintigraphy. An overview of contemporary techniques to measure biodistribution and kinetics of radiopharmaceuticals in small animal in vivo is presented. Theoretical as well as practical aspects of planar gamma camera and SPECT pinhole (PH) imaging are discussed. Current research is focusing on refining PH SPECT methodology, so specific regarding technical aspects and applications of PH SPECT will be reviewed. PMID:15869162

  12. A Fast Visible Camera Divertor-Imaging Diagnostic on DIII-D

    SciTech Connect

    Roquemore, A; Maingi, R; Lasnier, C; Nishino, N; Evans, T; Fenstermacher, M; Nagy, A

    2007-06-19

    In recent campaigns, the Photron Ultima SE fast framing camera has proven to be a powerful diagnostic when applied to imaging divertor phenomena on the National Spherical Torus Experiment (NSTX). Active areas of NSTX divertor research addressed with the fast camera include identification of types of EDGE Localized Modes (ELMs)[1], dust migration, impurity behavior and a number of phenomena related to turbulence. To compare such edge and divertor phenomena in low and high aspect ratio plasmas, a multi-institutional collaboration was developed for fast visible imaging on NSTX and DIII-D. More specifically, the collaboration was proposed to compare the NSTX small type V ELM regime [2] and the residual ELMs observed during Type I ELM suppression with external magnetic perturbations on DIII-D[3]. As part of the collaboration effort, the Photron camera was installed recently on DIII-D with a tangential view similar to the view implemented on NSTX, enabling a direct comparison between the two machines. The rapid implementation was facilitated by utilization of the existing optics that coupled the visible spectral output from the divertor vacuum ultraviolet UVTV system, which has a view similar to the view developed for the divertor tangential TV camera [4]. A remote controlled filter wheel was implemented, as was the radiation shield required for the DIII-D installation. The installation and initial operation of the camera are described in this paper, and the first images from the DIII-D divertor are presented.

  13. Camera sensor arrangement for crop/weed detection accuracy in agronomic images.

    PubMed

    Romeo, Juan; Guerrero, José Miguel; Montalvo, Martín; Emmi, Luis; Guijarro, María; Gonzalez-de-Santos, Pablo; Pajares, Gonzalo

    2013-01-01

    In Precision Agriculture, images coming from camera-based sensors are commonly used for weed identification and crop line detection, either to apply specific treatments or for vehicle guidance purposes. Accuracy of identification and detection is an important issue to be addressed in image processing. There are two main types of parameters affecting the accuracy of the images, namely: (a) extrinsic, related to the sensor's positioning in the tractor; (b) intrinsic, related to the sensor specifications, such as CCD resolution, focal length or iris aperture, among others. Moreover, in agricultural applications, the uncontrolled illumination, existing in outdoor environments, is also an important factor affecting the image accuracy. This paper is exclusively focused on two main issues, always with the goal to achieve the highest image accuracy in Precision Agriculture applications, making the following two main contributions: (a) camera sensor arrangement, to adjust extrinsic parameters and (b) design of strategies for controlling the adverse illumination effects. PMID:23549361

  14. Camera Sensor Arrangement for Crop/Weed Detection Accuracy in Agronomic Images

    PubMed Central

    Romeo, Juan; Guerrero, José Miguel; Montalvo, Martín; Emmi, Luis; Guijarro, María; Gonzalez-de-Santos, Pablo; Pajares, Gonzalo

    2013-01-01

    In Precision Agriculture, images coming from camera-based sensors are commonly used for weed identification and crop line detection, either to apply specific treatments or for vehicle guidance purposes. Accuracy of identification and detection is an important issue to be addressed in image processing. There are two main types of parameters affecting the accuracy of the images, namely: (a) extrinsic, related to the sensor's positioning in the tractor; (b) intrinsic, related to the sensor specifications, such as CCD resolution, focal length or iris aperture, among others. Moreover, in agricultural applications, the uncontrolled illumination, existing in outdoor environments, is also an important factor affecting the image accuracy. This paper is exclusively focused on two main issues, always with the goal to achieve the highest image accuracy in Precision Agriculture applications, making the following two main contributions: (a) camera sensor arrangement, to adjust extrinsic parameters and (b) design of strategies for controlling the adverse illumination effects. PMID:23549361

  15. Binarization method based on evolution equation for document images produced by cameras

    NASA Astrophysics Data System (ADS)

    Wang, Yan; He, Chuanjiang

    2012-04-01

    We present an evolution equation-based binarization method for document images produced by cameras. Unlike the existing thresholding techniques, the idea behind our method is that a family of gradually binarized images is obtained by the solution of an evolution partial differential equation, starting with an original image. In our formulation, the evolution is controlled by a global force and a local force, both of which have opposite sign inside and outside the object of interests in the original image. A simple finite difference scheme with a significantly larger time step is used to solve the evolution equation numerically; the desired binarization is typically obtained after only one or two iterations. Experimental results on 122 camera document images show that our method yields good visual quality and OCR performance.

  16. Acquisition method improvement for Bossa Nova Technologies' full Stokes, passive polarization imaging camera SALSA

    NASA Astrophysics Data System (ADS)

    El Ketara, M.; Vedel, M.; Breugnot, S.

    2016-05-01

    For some applications, the need for fast polarization acquisition is essential (if the scene observed is moving or changing quickly). In this paper, we present a new acquisition method for Bossa Nova Technologies' full Stokes passive polarization imaging camera, the SALSA. This polarization imaging camera is based on "Division of Time polarimetry" architecture. The use of this technique presents the advantage of preserving the full resolution of the image observed all the while reducing the speed acquisition time. The goal of this new acquisition method is to overcome the limitations associated with Division of Time acquisition technique as well as to obtain high-speed polarization imaging while maintaining the image resolution. The efficiency of this new method is demonstrated in this paper through different experiments.

  17. Shading correction of camera captured document image with depth map information

    NASA Astrophysics Data System (ADS)

    Wu, Chyuan-Tyng; Allebach, Jan P.

    2015-01-01

    Camera modules have become more popular in consumer electronics and office products. As a consequence, people have many opportunities to use a camera-based device to record a hardcopy document in their daily lives. However, it is easy to let undesired shading into the captured document image through the camera. Sometimes, this non-uniformity may degrade the readability of the contents. In order to mitigate this artifact, some solutions have been developed. But most of them are only suitable for particular types of documents. In this paper, we introduce a content-independent and shape-independent method that will lessen the shading effects in captured document images. We want to reconstruct the image such that the result will look like a document image captured under a uniform lighting source. Our method utilizes the 3D depth map of the document surface and a look-up table strategy. We will first discuss the model and the assumptions that we used for the approach. Then, the process of creating and utilizing the look-up table will be described in the paper. We implement this algorithm with our prototype 3D scanner, which also uses a camera module to capture a 2D image of the object. Some experimental results will be presented to show the effectiveness of our method. Both flat and curved surface document examples will be included.

  18. GNSS Carrier Phase Integer Ambiguity Resolution with Camera and Satellite images

    NASA Astrophysics Data System (ADS)

    Henkel, Patrick

    2015-04-01

    Ambiguity Resolution is the key to high precision position and attitude determination with GNSS. However, ambiguity resolution of kinematic receivers becomes challenging in environments with substantial multipath, limited satellite availability and erroneous cycle slip corrections. There is a need for other sensors, e.g. inertial sensors that allow an independent prediction of the position. The change of the predicted position over time can then be used for cycle slip detection and correction. In this paper, we provide a method to improve the initial ambiguity resolution for RTK and PPP with vision-based position information. Camera images are correlated with geo-referenced aerial/ satellite images to obtain an independent absolute position information. This absolute position information is then coupled with the GNSS and INS measurements in an extended Kalman filter to estimate the position, velocity, acceleration, attitude, angular rates, code multipath and biases of the accelerometers and gyroscopes. The camera and satellite images are matched based on some characteristic image points (e.g. corners of street markers). We extract these characteristic image points from the camera images by performing the following steps: An inverse mapping (homogenous projection) is applied to transform the camera images from the driver's perspective to bird view. Subsequently, we detect the street markers by performing (a) a color transformation and reduction with adaptive brightness correction to focus on relevant features, (b) a subsequent morphological operation to enhance the structure recognition, (c) an edge and corner detection to extract feature points, and (d) a point matching of the corner points with a template to recognize the street markers. We verified the proposed method with two low-cost u-blox LEA 6T GPS receivers, the MPU9150 from Invensense, the ASCOS RTK corrections and a PointGrey camera. The results show very precise and seamless position and attitude

  19. MTF measurement and imaging quality evaluation of digital camera with slanted-edge method

    NASA Astrophysics Data System (ADS)

    Xiang, Chunchang; Chen, Xinhua; Chen, Yuheng; Zhou, Jiankang; Shen, Weimin

    2010-11-01

    Modulation Transfer Function (MTF) is the spatial frequency response of imaging systems and now develops as an objective merit performance for evaluating both quality of lens and camera. Slanted-edge method and its principle for measuring MTF of digital camera are introduced in this paper. The setup and software for testing digital camera is respectively established and developed. Measurement results with different tilt angle of the knife edge are compared to discuss the influence of the tilt angle. Also carefully denoise of the knife edge image is performed to decrease the noise sensitivity of knife edge measurement. Comparisons have been made between the testing results gained by slanted-edge method and grating target technique, and their deviation is analyzed.

  20. Evaluation of a dual-panel PET camera design to breast cancer imaging.

    PubMed

    Zhang, Jin; Chinn, Gary; Foudray, Angela M K; Habte, Frezghi; Olcott, Peter; Levin, Craig S

    2006-01-01

    We are developing a novel, portable dual-panel positron emission tomography (PET) camera dedicated to breast cancer imaging. With a sensitive area of approximately 150 cm(2), this camera is based on arrays of lutetium oxyorthosilicate (LSO) crystals (1x1x3 mm(3)) coupled to 11x11-mm(2) position-sensitive avalanche photodiodes (PSAPD). GATE open source software was used to perform Monte Carlo simulations to optimize the parameters for the camera design. The noise equivalent counting (NEC) rate, together with the true, scatter, and random counting rates were simulated at different time and energy windows. Focal plane tomography (FPT) was used for visualizing the tumors at different depths between the two detector panels. Attenuation and uniformity corrections were applied to images. PMID:17646005

  1. Low-complexity camera digital signal imaging for video document projection system

    NASA Astrophysics Data System (ADS)

    Hsia, Shih-Chang; Tsai, Po-Shien

    2011-04-01

    We present high-performance and low-complexity algorithms for real-time camera imaging applications. The main functions of the proposed camera digital signal processing (DSP) involve color interpolation, white balance, adaptive binary processing, auto gain control, and edge and color enhancement for video projection systems. A series of simulations demonstrate that the proposed method can achieve good image quality while keeping computation cost and memory requirements low. On the basis of the proposed algorithms, the cost-effective hardware core is developed using Verilog HDL. The prototype chip has been verified with one low-cost programmable device. The real-time camera system can achieve 1270 × 792 resolution with the combination of extra components and can demonstrate each DSP function.

  2. Gamma camera calibration and validation for quantitative SPECT imaging with (177)Lu.

    PubMed

    D'Arienzo, M; Cazzato, M; Cozzella, M L; Cox, M; D'Andrea, M; Fazio, A; Fenwick, A; Iaccarino, G; Johansson, L; Strigari, L; Ungania, S; De Felice, P

    2016-06-01

    Over the last years (177)Lu has received considerable attention from the clinical nuclear medicine community thanks to its wide range of applications in molecular radiotherapy, especially in peptide-receptor radionuclide therapy (PRRT). In addition to short-range beta particles, (177)Lu emits low energy gamma radiation of 113keV and 208keV that allows gamma camera quantitative imaging. Despite quantitative cancer imaging in molecular radiotherapy having been proven to be a key instrument for the assessment of therapeutic response, at present no general clinically accepted quantitative imaging protocol exists and absolute quantification studies are usually based on individual initiatives. The aim of this work was to develop and evaluate an approach to gamma camera calibration for absolute quantification in tomographic imaging with (177)Lu. We assessed the gamma camera calibration factors for a Philips IRIX and Philips AXIS gamma camera system using various reference geometries, both in air and in water. Images were corrected for the major effects that contribute to image degradation, i.e. attenuation, scatter and dead- time. We validated our method in non-reference geometry using an anthropomorphic torso phantom provided with the liver cavity uniformly filled with (177)LuCl3. Our results showed that calibration factors depend on the particular reference condition. In general, acquisitions performed with the IRIX gamma camera provided good results at 208keV, with agreement within 5% for all geometries. The use of a Jaszczak 16mL hollow sphere in water provided calibration factors capable of recovering the activity in anthropomorphic geometry within 1% for the 208keV peak, for both gamma cameras. The point source provided the poorest results, most likely because scatter and attenuation correction are not incorporated in the calibration factor. However, for both gamma cameras all geometries provided calibration factors capable of recovering the activity in

  3. Orientation Modeling for Amateur Cameras by Matching Image Line Features and Building Vector Data

    NASA Astrophysics Data System (ADS)

    Hung, C. H.; Chang, W. C.; Chen, L. C.

    2016-06-01

    With the popularity of geospatial applications, database updating is getting important due to the environmental changes over time. Imagery provides a lower cost and efficient way to update the database. Three dimensional objects can be measured by space intersection using conjugate image points and orientation parameters of cameras. However, precise orientation parameters of light amateur cameras are not always available due to their costliness and heaviness of precision GPS and IMU. To automatize data updating, the correspondence of object vector data and image may be built to improve the accuracy of direct georeferencing. This study contains four major parts, (1) back-projection of object vector data, (2) extraction of image feature lines, (3) object-image feature line matching, and (4) line-based orientation modeling. In order to construct the correspondence of features between an image and a building model, the building vector features were back-projected onto the image using the initial camera orientation from GPS and IMU. Image line features were extracted from the imagery. Afterwards, the matching procedure was done by assessing the similarity between the extracted image features and the back-projected ones. Then, the fourth part utilized line features in orientation modeling. The line-based orientation modeling was performed by the integration of line parametric equations into collinearity condition equations. The experiment data included images with 0.06 m resolution acquired by Canon EOS Mark 5D II camera on a Microdrones MD4-1000 UAV. Experimental results indicate that 2.1 pixel accuracy may be reached, which is equivalent to 0.12 m in the object space.

  4. Retrieving Atmospheric Dust Loading on Mars Using Engineering Cameras and MSL's Mars Hand Lens Imager (MAHLI)

    NASA Astrophysics Data System (ADS)

    Wolfe, C. A.; Lemmon, M. T.

    2015-12-01

    Dust in the Martian atmosphere influences energy deposition, dynamics, and the viability of solar powered exploration vehicles. The Viking, Pathfinder, Spirit, Opportunity, Phoenix, and Curiosity landers and rovers each included the ability to image the Sun with a science camera equipped with a neutral density filter. Direct images of the Sun not only provide the ability to measure extinction by dust and ice in the atmosphere, but also provide a variety of constraints on the Martian dust and water cycles. These observations have been used to characterize dust storms, to provide ground truth sites for orbiter-based global measurements of dust loading, and to help monitor solar panel performance. In the cost-constrained environment of Mars exploration, future missions may omit such cameras, as the solar-powered InSight mission has. We seek to provide a robust capability of determining atmospheric opacity from sky images taken with cameras that have not been designed for solar imaging, such as the engineering cameras onboard Opportunity and the Mars Hand Lens Imager (MAHLI) on Curiosity. Our investigation focuses primarily on the accuracy of a method that determines optical depth values using scattering models that implement the ratio of sky radiance measurements at different elevation angles, but at the same scattering angle. Operational use requires the ability to retrieve optical depth on a timescale useful to mission planning, and with an accuracy and precision sufficient to support both mission planning and validating orbital measurements. We will present a simulation-based assessment of imaging strategies and their error budgets, as well as a validation based on the comparison of direct extinction measurements from archival Navcam, Hazcam, and MAHLI camera data.

  5. The application of camera calibration in range-gated 3D imaging technology

    NASA Astrophysics Data System (ADS)

    Liu, Xiao-quan; Wang, Xian-wei; Zhou, Yan

    2013-09-01

    Range-gated laser imaging technology was proposed in 1966 by LF Gillespiethe in U.S. Army Night Vision Laboratory(NVL). Using pulse laser and intensified charge-coupled device(ICCD) as light source and detector respectively, range-gated laser imaging technology can realize space-slice imaging while restraining the atmospheric backs-catter, and in turn detect the target effectively, by controlling the delay between the laser pulse and strobe. Owing to the constraints of the development of key components such as narrow pulse laser and gated imaging devices, the research has been progressed slowly in the next few decades. Until the beginning of this century, as the hardware technology continues to mature, this technology has developed rapidly in fields such as night vision, underwater imaging, biomedical imaging, three-dimensional imaging, especially range-gated three-dimensional(3-D) laser imaging field purposing of access to target spatial information. 3-D reconstruction is the processing of restoration of 3-D objects visible surface geometric structure from three-dimensional(2-D) image. Range-gated laser imaging technology can achieve gated imaging of slice space to form a slice image, and in turn provide the distance information corresponding to the slice image. But to inverse the information of 3-D space, we need to obtain the imaging visual field of system, that is, the focal length of the system. Then based on the distance information of the space slice, the spatial information of each unit space corresponding to each pixel can be inversed. Camera calibration is an indispensable step in 3-D reconstruction, including analysis of the internal structure of camera parameters and the external parameters . In order to meet the technical requirements of the range-gated 3-D imaging, this paper intends to study the calibration of the zoom lens system. After summarizing the camera calibration technique comprehensively, a classic calibration method based on line is

  6. High image quality sub 100 picosecond gated framing camera development

    SciTech Connect

    Price, R.H.; Wiedwald, J.D.

    1983-11-17

    A major challenge for laser fusion is the study of the symmetry and hydrodynamic stability of imploding fuel capsules. Framed x-radiographs of 10-100 ps duration, excellent image quality, minimum geometrical distortion (< 1%), dynamic range greater than 1000, and more than 200 x 200 pixels are required for this application. Recent progress on a gated proximity focused intensifier which meets these requirements is presented.

  7. The trustworthy digital camera: Restoring credibility to the photographic image

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L.

    1994-01-01

    The increasing sophistication of computers has made digital manipulation of photographic images, as well as other digitally-recorded artifacts such as audio and video, incredibly easy to perform and increasingly difficult to detect. Today, every picture appearing in newspapers and magazines has been digitally altered to some degree, with the severity varying from the trivial (cleaning up 'noise' and removing distracting backgrounds) to the point of deception (articles of clothing removed, heads attached to other people's bodies, and the complete rearrangement of city skylines). As the power, flexibility, and ubiquity of image-altering computers continues to increase, the well-known adage that 'the photography doesn't lie' will continue to become an anachronism. A solution to this problem comes from a concept called digital signatures, which incorporates modern cryptographic techniques to authenticate electronic mail messages. 'Authenticate' in this case means one can be sure that the message has not been altered, and that the sender's identity has not been forged. The technique can serve not only to authenticate images, but also to help the photographer retain and enforce copyright protection when the concept of 'electronic original' is no longer meaningful.

  8. A multiple-plate, multiple-pinhole camera for X-ray gamma-ray imaging

    NASA Technical Reports Server (NTRS)

    Hoover, R. B.

    1971-01-01

    Plates with identical patterns of precisely aligned pinholes constitute lens system which, when rotated about optical axis, produces continuous high resolution image of small energy X-ray or gamma ray source. Camera has applications in radiation treatment and nuclear medicine.

  9. Gamma-ray spectral imaging using a single-shutter radiation camera

    NASA Astrophysics Data System (ADS)

    DeVol, T. A.; Wehe, D. K.; Knoll, G. F.

    1990-12-01

    As part of a program to develop mobile robots for reactor environments, we are developing a radiation-imaging camera capable of operating in medium-intensity (<2 R/h), medium-energy (<8 MeV) gamma-ray fields. A systematic study of available detectors indicated the advisability of a high- Z scintillator. The raster-scanning camera uses a lead-shielded bismuth germanate (BGO) scintillator (1.25 cm×1.25 cm right-circular cylinder) coupled to a photomultiplier tube (PMT) operated in pulse mode. Measurements yielded an angular resolution of 2.5° and energy resolution of 12.9% at 662 keV. The camera motion is totally automated and controlled by stepping motors connected to a remote computer. Several 2D images of radioactive sources have been acquired in fields of up to 400 mR/h and energies up to 2.75 MeV. Some of the images demonstrate the ability of the camera to image a polychromatic field.

  10. Hyperspectral imaging using a color camera and its application for pathogen detection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reports the results of a feasibility study for the development of a hyperspectral image recovery (reconstruction) technique using a RGB color camera and regression analysis in order to detect and classify colonies of foodborne pathogens. The target bacterial pathogens were the six represe...

  11. Geologic Analysis of the Surface Thermal Emission Images Taken by the VMC Camera, Venus Express

    NASA Astrophysics Data System (ADS)

    Basilevsky, A. T.; Shalygin, E. V.; Titov, D. V.; Markiewicz, W. J.; Scholten, F.; Roatsch, Th.; Fiethe, B.; Osterloh, B.; Michalik, H.; Kreslavsky, M. A.; Moroz, L. V.

    2010-03-01

    Analysis of Venus Monitoring Camera 1-µm images and surface emission modeling showed apparent emissivity at Chimon-mana tessera and shows that Tuulikki volcano is higher than that of the adjacent plains; Maat Mons did not show any signature of ongoing volcanism.

  12. Film cameras or digital sensors? The challenge ahead for aerial imaging

    USGS Publications Warehouse

    Light, D.L.

    1996-01-01

    Cartographic aerial cameras continue to play the key role in producing quality products for the aerial photography business, and specifically for the National Aerial Photography Program (NAPP). One NAPP photograph taken with cameras capable of 39 lp/mm system resolution can contain the equivalent of 432 million pixels at 11 ??m spot size, and the cost is less than $75 per photograph to scan and output the pixels on a magnetic storage medium. On the digital side, solid state charge coupled device linear and area arrays can yield quality resolution (7 to 12 ??m detector size) and a broader dynamic range. If linear arrays are to compete with film cameras, they will require precise attitude and positioning of the aircraft so that the lines of pixels can be unscrambled and put into a suitable homogeneous scene that is acceptable to an interpreter. Area arrays need to be much larger than currently available to image scenes competitive in size with film cameras. Analysis of the relative advantages and disadvantages of the two systems show that the analog approach is more economical at present. However, as arrays become larger, attitude sensors become more refined, global positioning system coordinate readouts become commonplace, and storage capacity becomes more affordable, the digital camera may emerge as the imaging system for the future. Several technical challenges must be overcome if digital sensors are to advance to where they can support mapping, charting, and geographic information system applications.

  13. Research on the affect of differential-images technique to the resolution of infrared spatial camera

    NASA Astrophysics Data System (ADS)

    Jin, Guang; An, Yuan; Qi, Yingchun; Hu, Fusheng

    2007-12-01

    The optical system of infrared spatial camera adopts bigger relative aperture and bigger pixel size on focal plane element. These make the system have bulky volume and low resolution. The potential of the optical systems can not be exerted adequately. So, one method for improving resolution of infrared spatial camera based on multi-frame difference-images is introduced in the dissertation. The method uses more than one detectors to acquire several difference images, and then reconstructs a new high-resolution image from these images through the relationship of pixel grey value. The technique of difference-images that uses more than two detectors is researched, and it can improve the resolution 2.5 times in theory. The relationship of pixel grey value between low-resolution difference-images and high-resolution image is found by analyzing the energy of CCD sampling, a general relationship between the enhanced times of the resolution of the detected figure with differential method and the least count of CCD that will be used to detect figure is given. Based on the research of theory, the implementation process of utilizing difference-images technique to improve the resolution of the figure was simulated used Matlab software by taking a personality image as the object, and the software can output the result as an image. The result gotten from the works we have finished proves that the technique is available in high-resolution image reconstruction. The resolution of infrared spatial camera can be improved evidently when holding the size of optical structure or using big size detector by applying for difference image technique. So the technique has a high value in optical remote fields.

  14. Quantitative Evaluation of Surface Color of Tomato Fruits Cultivated in Remote Farm Using Digital Camera Images

    NASA Astrophysics Data System (ADS)

    Hashimoto, Atsushi; Suehara, Ken-Ichiro; Kameoka, Takaharu

    To measure the quantitative surface color information of agricultural products with the ambient information during cultivation, a color calibration method for digital camera images and a remote monitoring system of color imaging using the Web were developed. Single-lens reflex and web digital cameras were used for the image acquisitions. The tomato images through the post-ripening process were taken by the digital camera in both the standard image acquisition system and in the field conditions from the morning to evening. Several kinds of images were acquired with the standard RGB color chart set up just behind the tomato fruit on a black matte, and a color calibration was carried out. The influence of the sunlight could be experimentally eliminated, and the calibrated color information consistently agreed with the standard ones acquired in the system through the post-ripening process. Furthermore, the surface color change of the tomato on the tree in a greenhouse was remotely monitored during maturation using the digital cameras equipped with the Field Server. The acquired digital color images were sent from the Farm Station to the BIFE Laboratory of Mie University via VPN. The time behavior of the tomato surface color change during the maturing process could be measured using the color parameter calculated based on the obtained and calibrated color images along with the ambient atmospheric record. This study is a very important step in developing the surface color analysis for both the simple and rapid evaluation of the crop vigor in the field and to construct an ambient and networked remote monitoring system for food security, precision agriculture, and agricultural research.

  15. The iQID camera: An ionizing-radiation quantum imaging detector

    PubMed Central

    Miller, Brian W.; Gregory, Stephanie J.; Fuller, Erin S.; Barrett, Harrison H.; Barber, H. Bradford; Furenlid, Lars R.

    2015-01-01

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detector’s response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The confirmed response to this broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated by particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. The spatial location and energy of individual particles are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, excellent detection efficiency for charged particles, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discriminate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is real-time, single-particle digital autoradiography. We present the latest results and discuss potential applications. PMID:26166921

  16. The iQID Camera: An Ionizing-Radiation Quantum Imaging Detector

    SciTech Connect

    Miller, Brian W.; Gregory, Stephanie J.; Fuller, Erin S.; Barrett, Harrison H.; Barber, Bradford H.; Furenlid, Lars R.

    2014-06-11

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detectors response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The detector’s response to a broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. Individual particles are identified and their spatial position (to sub-pixel accuracy) and energy are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, high sensitivity, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discrimate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is single-particle, real-time digital autoradiography. In conclusion, we present the latest results and discuss potential applications.

  17. The iQID Camera: An Ionizing-Radiation Quantum Imaging Detector

    DOE PAGESBeta

    Miller, Brian W.; Gregory, Stephanie J.; Fuller, Erin S.; Barrett, Harrison H.; Barber, Bradford H.; Furenlid, Lars R.

    2014-06-11

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detectors response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The detector’s response to a broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated particle interactions is optically amplified by the intensifier andmore » then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. Individual particles are identified and their spatial position (to sub-pixel accuracy) and energy are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, high sensitivity, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discrimate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is single-particle, real-time digital autoradiography. In conclusion, we present the latest results and discuss potential applications.« less

  18. The iQID camera: An ionizing-radiation quantum imaging detector

    NASA Astrophysics Data System (ADS)

    Miller, Brian W.; Gregory, Stephanie J.; Fuller, Erin S.; Barrett, Harrison H.; Bradford Barber, H.; Furenlid, Lars R.

    2014-12-01

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detector's response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The confirmed response to this broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated by particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. The spatial location and energy of individual particles are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, excellent detection efficiency for charged particles, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discriminate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is real-time, single-particle digital autoradiography. We present the latest results and discuss potential applications.

  19. The iQID Camera An Ionizing-Radiation Quantum Imaging Detector

    SciTech Connect

    Miller, Brian W.; Gregory, Stephanie J.; Fuller, Erin S.; Barrett, Harrison H.; Barber, Bradford H.; Furenlid, Lars R.

    2014-06-11

    Abstract We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detectors response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The detector’s response to a broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. Individual particles are identified and their spatial position (to sub-pixel accuracy) and energy are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, high sensitivity, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discrimate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is single-particle, real-time digital autoradiography. We present the latest results and discuss potential applications.

  20. Impact Chronology of the Moon — Results from the Lunar Reconnaissance Orbiter Camera (LROC)

    NASA Astrophysics Data System (ADS)

    Hiesinger, H.; van der Bogert, C. H.; Pasckert, J. H.; Plescia, J. B.; Robinson, M. S.

    2016-05-01

    We present absolute model ages (AMAs) based on crater size-frequency distribution (CSFD) measurements for Copernicus, Tycho, North Ray, Cone, and Autolycus craters to test and possibly improve the lunar cratering chronology.

  1. 3D motion artifact compenstation in CT image with depth camera

    NASA Astrophysics Data System (ADS)

    Ko, Youngjun; Baek, Jongduk; Shim, Hyunjung

    2015-02-01

    Computed tomography (CT) is a medical imaging technology that projects computer-processed X-rays to acquire tomographic images or the slices of specific organ of body. A motion artifact caused by patient motion is a common problem in CT system and may introduce undesirable artifacts in CT images. This paper analyzes the critical problems in motion artifacts and proposes a new CT system for motion artifact compensation. We employ depth cameras to capture the patient motion and account it for the CT image reconstruction. In this way, we achieve the significant improvement in motion artifact compensation, which is not possible by previous techniques.

  2. Improvement of camera arrangement in computer-generated holograms synthesized from multi-view images

    NASA Astrophysics Data System (ADS)

    Hayashi, Noriyuki; Sakamoto, Yuji; Honda, Yasuhiro

    2011-02-01

    Computer-generated hologram (CGH) is a technique that enables recording optical systems for holography by computer simulation, and can reconstruct ideal 3D images. Since CGH requires the model data of objects, it is necessary for creating 3D images of real existing objects to model them precisely. However, it is often difficult to obtain this data. To solve this problem, there has been much research into multi-view projection image based methods that do not require 3D model data. CGH using integral photography and CGH using multi-view projection obtained by lens array are examples of this research. However, these methods have some problems. First, their optical recording systems are complex and expensive, and therefore, realizing these systems is difficult. Another problem is that enormous projections are required to generate a hologram with sufficient pixel size. In the past, a method to generate holograms from multi-view images taken with digital cameras was proposed. Additionally, to generate CGHs using multi-view images from randomly arranged cameras, we proposed a method that uses distance transformations, rotations of light waves, and an algorithm that sets up hologram parameters automatically by using camera arrangement information. In this paper, the results of numerical reconstructions are compared, and both the motion parallax and resolution of the reconstructed images are discussed. The proper number of multi-view projections needed will be derived from this discussion.

  3. Preliminary experience with small animal SPECT imaging on clinical gamma cameras.

    PubMed

    Aguiar, P; Silva-Rodríguez, J; Herranz, M; Ruibal, A

    2014-01-01

    The traditional lack of techniques suitable for in vivo imaging has induced a great interest in molecular imaging for preclinical research. Nevertheless, its use spreads slowly due to the difficulties in justifying the high cost of the current dedicated preclinical scanners. An alternative for lowering the costs is to repurpose old clinical gamma cameras to be used for preclinical imaging. In this paper we assess the performance of a portable device, that is, working coupled to a single-head clinical gamma camera, and we present our preliminary experience in several small animal applications. Our findings, based on phantom experiments and animal studies, provided an image quality, in terms of contrast-noise trade-off, comparable to dedicated preclinical pinhole-based scanners. We feel that our portable device offers an opportunity for recycling the widespread availability of clinical gamma cameras in nuclear medicine departments to be used in small animal SPECT imaging and we hope that it can contribute to spreading the use of preclinical imaging within institutions on tight budgets. PMID:24963478

  4. Real-time full-field photoacoustic imaging using an ultrasonic camera

    NASA Astrophysics Data System (ADS)

    Balogun, Oluwaseyi; Regez, Brad; Zhang, Hao F.; Krishnaswamy, Sridhar

    2010-03-01

    A photoacoustic imaging system that incorporates a commercial ultrasonic camera for real-time imaging of two-dimensional (2-D) projection planes in tissue at video rate (30 Hz) is presented. The system uses a Q-switched frequency-doubled Nd:YAG pulsed laser for photoacoustic generation. The ultrasonic camera consists of a 2-D 12×12 mm CCD chip with 120×120 piezoelectric sensing elements used for detecting the photoacoustic pressure distribution radiated from the target. An ultrasonic lens system is placed in front of the chip to collect the incoming photoacoustic waves, providing the ability for focusing and imaging at different depths. Compared with other existing photoacoustic imaging techniques, the camera-based system is attractive because it is relatively inexpensive and compact, and it can be tailored for real-time clinical imaging applications. Experimental results detailing the real-time photoacoustic imaging of rubber strings and buried absorbing targets in chicken breast tissue are presented, and the spatial resolution of the system is quantified.

  5. High-speed camera with real time processing for frequency domain imaging

    PubMed Central

    Shia, Victor; Watt, David; Faris, Gregory W.

    2011-01-01

    We describe a high-speed camera system for frequency domain imaging suitable for applications such as in vivo diffuse optical imaging and fluorescence lifetime imaging. 14-bit images are acquired at 2 gigapixels per second and analyzed with real-time pipeline processing using field programmable gate arrays (FPGAs). Performance of the camera system has been tested both for RF-modulated laser imaging in combination with a gain-modulated image intensifier and a simpler system based upon an LED light source. System amplitude and phase noise are measured and compared against theoretical expressions in the shot noise limit presented for different frequency domain configurations. We show the camera itself is capable of shot noise limited performance for amplitude and phase in as little as 3 ms, and when used in combination with the intensifier the noise levels are nearly shot noise limited. The best phase noise in a single pixel is 0.04 degrees for a 1 s integration time. PMID:21750770

  6. Wide Field Camera 3: A Powerful New Imager for the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Kimble, Randy

    2008-01-01

    Wide Field Camera 3 (WFC3) is a powerful UV/visible/near-infrared camera in development for installation into the Hubble Space Telescope during upcoming Servicing Mission 4. WFC3 provides two imaging channels. The UVIS channel incorporates a 4096 x 4096 pixel CCD focal plane with sensitivity from 200 to 1000 nm. The IR channel features a 1024 x 1024 pixel HgCdTe focal plane covering 850 to 1700 nm. We report here on the design of the instrument, the performance of its flight detectors, results of the ground test and calibration program, and the plans for the Servicing Mission installation and checkout.

  7. MONICA: a compact, portable dual gamma camera system for mouse whole-body imaging

    SciTech Connect

    Choyke, Peter L; Xia, Wenze; Seidel, Jurgen; Kakareka, John W; Pohida, Thomas J; Milenic, Diane E; Proffitt, James; Majewski, Stan; Weisenberger, Andrew G; Green, Michael V

    2010-04-01

    Introduction We describe a compact, portable dual-gamma camera system (named "MONICA" for MObile Nuclear Imaging CAmeras) for visualizing and analyzing the whole-body biodistribution of putative diagnostic and therapeutic single photon emitting radiotracers in animals the size of mice. Methods Two identical, miniature pixelated NaI(Tl) gamma cameras were fabricated and installed ?looking up? through the tabletop of a compact portable cart. Mice are placed directly on the tabletop for imaging. Camera imaging performance was evaluated with phantoms and field performance was evaluated in a weeklong In-111 imaging study performed in a mouse tumor xenograft model. Results Tc-99m performance measurements, using a photopeak energy window of 140 keV?10%, yielded the following results: spatial resolution (FWHM at 1 cm), 2.2 mm; sensitivity, 149 cps (counts per seconds)/MBq (5.5 cps/μCi); energy resolution (FWHM, full width at half maximum), 10.8%; count rate linearity (count rate vs. activity), r2=0.99 for 0?185 MBq (0?5 mCi) in the field of view (FOV); spatial uniformity, <3% count rate variation across the FOV. Tumor and whole-body distributions of the In-111 agent were well visualized in all animals in 5-min images acquired throughout the 168-h study period. Conclusion Performance measurements indicate that MONICA is well suited to whole-body single photon mouse imaging. The field study suggests that inter-device communications and user-oriented interfaces included in the MONICA design facilitate use of the system in practice. We believe that MONICA may be particularly useful early in the (cancer) drug development cycle where basic whole-body biodistribution data can direct future development of the agent under study and where logistical factors, e.g., limited imaging space, portability and, potentially, cost are important.

  8. Skyline matching based camera orientation from images and mobile mapping point clouds

    NASA Astrophysics Data System (ADS)

    Hofmann, S.; Eggert, D.; Brenner, C.

    2014-05-01

    Mobile Mapping is widely used for collecting large amounts of geo-referenced data. An important role plays sensor fusion, in order to evaluate multiple sensors such as laser scanner and cameras jointly. This requires to determine the relative orientation between sensors. Based on data of a RIEGL VMX-250 mobile mapping system equipped with two laser scanners, four optional cameras, and a highly precise GNSS/IMU system, we propose an approach to improve camera orientations. A manually determined orientation is used as an initial approximation for matching a large number of points in optical images and the corresponding projected scan images. The search space of the point correspondences is reduced to skylines found in both the optical as well as the scan image. The skyline determination is based on alpha shapes, the actual matching is done via an adapted ICP algorithm. The approximate values of the relative orientation are used as starting values for an iterative resection process. Outliers are removed at several stages of the process. Our approach is fully automatic and improves the camera orientation significantly.

  9. Advanced High-Speed Framing Camera Development for Fast, Visible Imaging Experiments

    SciTech Connect

    Amy Lewis, Stuart Baker, Brian Cox, Abel Diaz, David Glass, Matthew Martin

    2011-05-11

    The advances in high-voltage switching developed in this project allow a camera user to rapidly vary the number of output frames from 1 to 25. A high-voltage, variable-amplitude pulse train shifts the deflection location to the new frame location during the interlude between frames, making multiple frame counts and locations possible. The final deflection circuit deflects to five different frame positions per axis, including the center position, making for a total of 25 frames. To create the preset voltages, electronically adjustable {+-}500 V power supplies were chosen. Digital-to-analog converters provide digital control of the supplies. The power supplies are clamped to {+-}400 V so as not to exceed the voltage ratings of the transistors. A field-programmable gated array (FPGA) receives the trigger signal and calculates the combination of plate voltages for each frame. The interframe time and number of frames are specified by the user, but are limited by the camera electronics. The variable-frame circuit shifts the plate voltages of the first frame to those of the second frame during the user-specified interframe time. Designed around an electrostatic image tube, a framing camera images the light present during each frame (at the photocathode) onto the tube’s phosphor. The phosphor persistence allows the camera to display multiple frames on the phosphor at one time. During this persistence, a CCD camera is triggered and the analog image is collected digitally. The tube functions by converting photons to electrons at the negatively charged photocathode. The electrons move quickly toward the more positive charge of the phosphor. Two sets of deflection plates skew the electron’s path in horizontal and vertical (x axis and y axis, respectively) directions. Hence, each frame’s electrons bombard the phosphor surface at a controlled location defined by the voltages on the deflection plates. To prevent the phosphor from being exposed between frames, the image tube

  10. Validation of spectral sky radiance derived from all-sky camera images - a case study

    NASA Astrophysics Data System (ADS)

    Tohsing, K.; Schrempf, M.; Riechelmann, S.; Seckmeyer, G.

    2014-07-01

    Spectral sky radiance (380-760 nm) is derived from measurements with a hemispherical sky imager (HSI) system. The HSI consists of a commercial compact CCD (charge coupled device) camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue. To obtain the spectral sky radiance from these images, non-linear regression functions for various sky conditions have been derived. The camera-based spectral sky radiance was validated using spectral sky radiance measured with a CCD spectroradiometer. The spectral sky radiance for complete distribution over the hemisphere between both instruments deviates by less than 20% at 500 nm for all sky conditions and for zenith angles less than 80°. The reconstructed spectra of the wavelengths 380-760 nm between both instruments at various directions deviate by less than 20% for all sky conditions.

  11. Validation of spectral sky radiance derived from all-sky camera images - a case study

    NASA Astrophysics Data System (ADS)

    Tohsing, K.; Schrempf, M.; Riechelmann, S.; Seckmeyer, G.

    2014-01-01

    Spectral sky radiance (380-760 nm) is derived from measurements with a Hemispherical Sky Imager (HSI) system. The HSI consists of a commercial compact CCD (charge coupled device) camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue. To obtain the spectral sky radiance from these images non-linear regression functions for various sky conditions have been derived. The camera-based spectral sky radiance was validated by spectral sky radiance measured with a CCD spectroradiometer. The spectral sky radiance for complete distribution over the hemisphere between both instruments deviates by less than 20% at 500 nm for all sky conditions and for zenith angles less than 80°. The reconstructed spectra of the wavelength 380 nm to 760 nm between both instruments at various directions deviate by less then 20% for all sky conditions.

  12. Single Image Camera Calibration in Close Range Photogrammetry for Solder Joint Analysis

    NASA Astrophysics Data System (ADS)

    Heinemann, D.; Knabner, S.; Baumgarten, D.

    2016-06-01

    Printed Circuit Boards (PCB) play an important role in the manufacturing of electronic devices. To ensure a correct function of the PCBs a certain amount of solder paste is needed during the placement of components. The aim of the current research is to develop an real-time, closed-loop solution for the analysis of the printing process where solder is printed onto PCBs. Close range photogrammetry allows for determination of the solder volume and a subsequent correction if necessary. Photogrammetry is an image based method for three dimensional reconstruction from two dimensional image data of an object. A precise camera calibration is indispensable for an accurate reconstruction. In our certain application it is not possible to use calibration methods with two dimensional calibration targets. Therefore a special calibration target was developed and manufactured, which allows for single image camera calibration.

  13. Measuring the image quality of digital-camera sensors by a ping-pong ball

    NASA Astrophysics Data System (ADS)

    Pozo, Antonio M.; Rubiño, Manuel; Castro, José J.; Salas, Carlos; Pérez-Ocón, Francisco

    2014-07-01

    In this work, we present a low-cost experimental setup to evaluate the image quality of digital-camera sensors, which can be implemented in undergraduate and postgraduate teaching. The method consists of evaluating the modulation transfer function (MTF) of digital-camera sensors by speckle patterns using a ping-pong ball as a diffuser, with two handmade circular apertures acting as input and output ports, respectively. To specify the spatial-frequency content of the speckle pattern, it is necessary to use an aperture; for this, we made a slit in a piece of black cardboard. First, the MTF of a digital-camera sensor was calculated using the ping-pong ball and the handmade slit, and then the MTF was calculated using an integrating sphere and a high-quality steel slit. Finally, the results achieved with both experimental setups were compared, showing a similar MTF in both cases.

  14. Stereo Imaging Velocimetry Technique Using Standard Off-the-Shelf CCD Cameras

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2004-01-01

    Stereo imaging velocimetry is a fluid physics technique for measuring three-dimensional (3D) velocities at a plurality of points. This technique provides full-field 3D analysis of any optically clear fluid or gas experiment seeded with tracer particles. Unlike current 3D particle imaging velocimetry systems that rely primarily on laser-based systems, stereo imaging velocimetry uses standard off-the-shelf charge-coupled device (CCD) cameras to provide accurate and reproducible 3D velocity profiles for experiments that require 3D analysis. Using two cameras aligned orthogonally, we present a closed mathematical solution resulting in an accurate 3D approximation of the observation volume. The stereo imaging velocimetry technique is divided into four phases: 3D camera calibration, particle overlap decomposition, particle tracking, and stereo matching. Each phase is explained in detail. In addition to being utilized for space shuttle experiments, stereo imaging velocimetry has been applied to the fields of fluid physics, bioscience, and colloidal microscopy.

  15. Camera-Based Lock-in and Heterodyne Carrierographic Photoluminescence Imaging of Crystalline Silicon Wafers

    NASA Astrophysics Data System (ADS)

    Sun, Q. M.; Melnikov, A.; Mandelis, A.

    2015-06-01

    Carrierographic (spectrally gated photoluminescence) imaging of a crystalline silicon wafer using an InGaAs camera and two spread super-bandgap illumination laser beams is introduced in both low-frequency lock-in and high-frequency heterodyne modes. Lock-in carrierographic images of the wafer up to 400 Hz modulation frequency are presented. To overcome the frame rate and exposure time limitations of the camera, a heterodyne method is employed for high-frequency carrierographic imaging which results in high-resolution near-subsurface information. The feasibility of the method is guaranteed by the typical superlinearity behavior of photoluminescence, which allows one to construct a slow enough beat frequency component from nonlinear mixing of two high frequencies. Intensity-scan measurements were carried out with a conventional single-element InGaAs detector photocarrier radiometry system, and the nonlinearity exponent of the wafer was found to be around 1.7. Heterodyne images of the wafer up to 4 kHz have been obtained and qualitatively analyzed. With the help of the complementary lock-in and heterodyne modes, camera-based carrierographic imaging in a wide frequency range has been realized for fundamental research and industrial applications toward in-line nondestructive testing of semiconductor materials and devices.

  16. Synthesizing wide-angle and arbitrary view-point images from a circular camera array

    NASA Astrophysics Data System (ADS)

    Fukushima, Norishige; Yendo, Tomohiro; Fujii, Toshiaki; Tanimoto, Masayuki

    2006-02-01

    We propose a technique of Imaged-Based Rendering(IBR) using a circular camera array. By the result of having recorded the scene as surrounding the surroundings, we can synthesize a more dynamic arbitrary viewpoint images and a wide angle images like a panorama . This method is based on Ray- Space, one of the image-based rendering, like Light Field. Ray-Space is described by the position (x, y) and a direction (θ, φ) of the ray's parameter which passes a reference plane. All over this space, when the camera has been arranged circularly, the orbit of the point equivalent to an Epipor Plane Image(EPI) at the time of straight line arrangement draws a sin curve. Although described in a very clear form, in case a rendering is performed, pixel of which position of which camera being used and the work for which it asks become complicated. Therefore, the position (u, v) of the position (s, t) pixel of a camera like Light Filed redescribes space expression. It makes the position of a camera a polar-coordinates system (r, theta), and is making it close to description of Ray-Space. Thereby, although the orbit of a point serves as a complicated periodic function of periodic 2pi, the handling of a rendering becomes easy. From such space, the same as straight line arrangement, arbitrary viewpoint picture synthesizing is performed only due to a geometric relationship between cameras. Moreover, taking advantage of the characteristic of concentrating on one circular point, we propose the technique of generating a wide-angle picture like a panorama. When synthesizing a viewpoint, since it is overlapped and is recording the ray of all the directions of the same position, this becomes possible. Having stated until now is the case where it is a time of the camera fully having been arranged and a plenoptic sampling being filled. The discrete thing which does not fill a sampling is described from here. When arranging a camera in a straight line and compounding a picture, in spite of

  17. Image restoration of hybrid time delay and integration camera system with residual motion

    NASA Astrophysics Data System (ADS)

    Zheng, Zhenzhen; Wu, Jiagu; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2011-06-01

    In this paper, we present a hybrid system for time delay and integration (TDI) image restoration. Images are degraded by residual motion, which distorts and blurs the TDI images during exposures and excludes the along-track scanning motion. The motion trajectory is estimated from the image sequence captured by an auxiliary high-speed camera. In order to make the estimated results less sensitive to the imaging conditions and noise, a new method based on cross-correlation is introduced for motion estimation. Then geometric distortion of the TDI image is removed by choosing the correct blurred block according to the central of the corresponding motion trajectory and the final image is restored row by row with the Richardson-Lucy algorithm. Simulated and experimental results are given to prove the effectiveness of our system.

  18. Note: In vivo pH imaging system using luminescent indicator and color camera

    NASA Astrophysics Data System (ADS)

    Sakaue, Hirotaka; Dan, Risako; Shimizu, Megumi; Kazama, Haruko

    2012-07-01

    Microscopic in vivo pH imaging system is developed that can capture the luminescent- and color-imaging. The former gives a quantitative measurement of a pH distribution in vivo. The latter captures the structural information that can be overlaid to the pH distribution for correlating the structure of a specimen and its pH distribution. By using a digital color camera, a luminescent image as well as a color image is obtained. The system uses HPTS (8-hydroxypyrene-1,3,6-trisulfonate) as a luminescent pH indicator for the luminescent imaging. Filter units are mounted in the microscope, which extract two luminescent images for using the excitation-ratio method. A ratio of the two images is converted to a pH distribution through a priori pH calibration. An application of the system to epidermal cells of Lactuca Sativa L is shown.

  19. A Compton camera for low energy gamma ray imaging in nuclear medicine applications

    NASA Astrophysics Data System (ADS)

    Leblanc, James Walter

    C-SPRINT is a prototype electronically-collimated imaging system that has been built using pixellated, low-noise, position-sensitive silicon as the first detector, and a sodium iodide scintillation detector ring as the second detector. The camera was intended to characterize potential performance gains of Compton cameras in nuclear medicine applications. The system consists of a single 4.5 x 1.5 x 0.03 cm3 silicon pad detector module with 2 keV energy resolution centered at the front face of a 50 cm diameter, 12 cm long NaI detector annulus. Calculations of the Uniform Cramer-Rao lower bound show that a "design Compton camera" based on our prototype can challenge existing mechanically-collimated systems at low to medium energies (˜140.5 - 400 keV) despite the deleterious effects of Doppler broadening. Measurements with our current system have yielded system sensitivity and spatial resolution estimates using 99mTc and 131I isotopes. Results showed an absolute efficiency of 1.8 x 10 -7 for 99mTc and 1.2 x 10-6 for 131I. The 99mTc value is an order of magnitude lower than predicted because of a combination of worse than expected silicon detector triggering performance, timing resolution issues, and system dead time effects. After correcting for these, efficiency predictions based on Monte Carlo analysis fall within 10% of the measured values. Spatial resolution estimates are also within 10% of analytical predictions. Measured resolution for the 99mTc point source was 15 min FWHM while in the 131I case, resolution improved to 8 mm FWHM. Extended source imaging was performed to characterize system performance under more challenging conditions. Images obtained were compared with measurements using a clinically-available mechanically collimated Anger camera. A resolution-variance study was also conducted for both isotopes. The results showed that the C-SPRINT camera performance on a per-detected photon basis was worse than the Anger camera for 99mTc but was similar for

  20. SU-E-E-06: Teaching About the Gamma Camera and Ultrasound Imaging

    SciTech Connect

    Lowe, M; Spiro, A; Vogel, R; Donaldson, N; Gosselin, C

    2015-06-15

    Purpose: Instructional modules on applications of physics in medicine are being developed. The target audience consists of students who have had an introductory undergraduate physics course. This presentation will concentrate on an active learning approach to teach the principles of the gamma camera. There will also be a description of an apparatus to teach ultrasound imaging. Methods: Since a real gamma camera is not feasible in the undergraduate classroom, we have developed two types of optical apparatus that teach the main principles. To understand the collimator, LEDS mimic gamma emitters in the body, and the photons pass through an array of tubes. The distance, spacing, diameter, and length of the tubes can be varied to understand the effect upon the resolution of the image. To determine the positions of the gamma emitters, a second apparatus uses a movable green laser, fluorescent plastic in lieu of the scintillation crystal, acrylic rods that mimic the PMTs, and a photodetector to measure the intensity. The position of the laser is calculated with a centroid algorithm.To teach the principles of ultrasound imaging, we are using the sound head and pulser box of an educational product, variable gain amplifier, rotation table, digital oscilloscope, Matlab software, and phantoms. Results: Gamma camera curriculum materials have been implemented in the classroom at Loyola in 2014 and 2015. Written work shows good knowledge retention and a more complete understanding of the material. Preliminary ultrasound imaging materials were run in 2015. Conclusion: Active learning methods add another dimension to descriptions in textbooks and are effective in keeping the students engaged during class time. The teaching apparatus for the gamma camera and ultrasound imaging can be expanded to include more cases, and could potentially improve students’ understanding of artifacts and distortions in the images.

  1. [The hyperspectral camera side-scan geometric imaging in any direction considering the spectral mixing].

    PubMed

    Wang, Shu-Min; Zhang, Ai-Wu; Hu, Shao-Xing; Sun, Wei-Dong

    2014-07-01

    In order to correct the image distortion in the hyperspectral camera side-scan geometric Imaging, the image pixel geo-referenced algorithm was deduced in detail in the present paper, which is suitable to the linear push-broom camera side-scan imaging on the ground in any direction. It takes the orientation of objects in the navigation coordinates system into account. Combined with the ground sampling distance of geo-referenced image and the area of push broom imaging, the general process of geo-referenced image divided into grids is also presented. The new image rows and columns will be got through the geo-referenced image area dividing the ground sampling distance. Considering the error produced by round rule in the pixel grids generated progress, and the spectral mixing problem caused by traditional direct spectral sampling method in the process of image correction, the improved spectral sampling method based on the weighted fusion method was proposed. It takes the area proportion of adjacent pixels in the new generated pixel as coefficient and then the coefficients are normalized to avoid the spectral overflow. So the new generated pixel is combined with the geo-referenced adjacent pixels spectral. Finally the amounts of push-broom imaging experiments were taken on the ground, and the distortion images were corrected according to the algorithm proposed above. The results show that the linear image distortion correction algorithm is valid and robust. At the same time, multiple samples were selected in the corrected images to verify the spectral data. The results indicate that the improved spectral sampling method is better than the direct spectral sampling algorithm. It provides reference for the application of similar productions on the ground. PMID:25269321

  2. Automatic Generation of Passer-by Record Images using Internet Camera

    NASA Astrophysics Data System (ADS)

    Terada, Kenji; Atsuta, Koji

    Recently, many brutal crimes have shocked us. On the other hand, we have seen a decline in the number of solved crimes. Therefore, the importance of security and self-defense has increased more and more. As an example of self-defense, many surveillance cameras are set up in the buildings, homes and offices. But even if we want to detect a suspicious person, we cannot check the surveillance videos immediately so that huge number of image sequences is stored in each video system. In this paper, we propose an automatic method of generating passer-by record images by using internet camera. In first step, the process of recognizing passer-by is carried out using an image sequence obtained from the internet camera. Our method classifies the subject region into each person by using the space-time image. In addition, we obtain the information of the time, direction and number of passey-by persons from this space-time image. Next, the present method detects five characteristics: the gravity of center, the position of person's head, the brightness, the size, and the shape of person. Finaly, an image of each person is selected among the image sequence by integrating five characteristics, and is added into the passer-by record image. Some experimental results using a simple experimental system are also reported, which indicate effectiveness of the proposed method. In most scenes, the every persons was able to be detected by the proposed method and the passer-by record image was generated.

  3. Hyperspectral imaging using a color camera and its application for pathogen detection

    NASA Astrophysics Data System (ADS)

    Yoon, Seung-Chul; Shin, Tae-Sung; Heitschmidt, Gerald W.; Lawrence, Kurt C.; Park, Bosoon; Gamble, Gary

    2015-02-01

    This paper reports the results of a feasibility study for the development of a hyperspectral image recovery (reconstruction) technique using a RGB color camera and regression analysis in order to detect and classify colonies of foodborne pathogens. The target bacterial pathogens were the six representative non-O157 Shiga-toxin producing Escherichia coli (STEC) serogroups (O26, O45, O103, O111, O121, and O145) grown in Petri dishes of Rainbow agar. The purpose of the feasibility study was to evaluate whether a DSLR camera (Nikon D700) could be used to predict hyperspectral images in the wavelength range from 400 to 1,000 nm and even to predict the types of pathogens using a hyperspectral STEC classification algorithm that was previously developed. Unlike many other studies using color charts with known and noise-free spectra for training reconstruction models, this work used hyperspectral and color images, separately measured by a hyperspectral imaging spectrometer and the DSLR color camera. The color images were calibrated (i.e. normalized) to relative reflectance, subsampled and spatially registered to match with counterpart pixels in hyperspectral images that were also calibrated to relative reflectance. Polynomial multivariate least-squares regression (PMLR) was previously developed with simulated color images. In this study, partial least squares regression (PLSR) was also evaluated as a spectral recovery technique to minimize multicollinearity and overfitting. The two spectral recovery models (PMLR and PLSR) and their parameters were evaluated by cross-validation. The QR decomposition was used to find a numerically more stable solution of the regression equation. The preliminary results showed that PLSR was more effective especially with higher order polynomial regressions than PMLR. The best classification accuracy measured with an independent test set was about 90%. The results suggest the potential of cost-effective color imaging using hyperspectral image

  4. Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging

    SciTech Connect

    Andreozzi, Jacqueline M. Glaser, Adam K.; Zhang, Rongxiao; Jarvis, Lesley A.; Gladstone, David J.; Pogue, Brian W.

    2015-02-15

    Purpose: To identify achievable camera performance and hardware needs in a clinical Cherenkov imaging system for real-time, in vivo monitoring of the surface beam profile on patients, as novel visual information, documentation, and possible treatment verification for clinicians. Methods: Complementary metal-oxide-semiconductor (CMOS), charge-coupled device (CCD), intensified charge-coupled device (ICCD), and electron multiplying-intensified charge coupled device (EM-ICCD) cameras were investigated to determine Cherenkov imaging performance in a clinical radiotherapy setting, with one emphasis on the maximum supportable frame rate. Where possible, the image intensifier was synchronized using a pulse signal from the Linac in order to image with room lighting conditions comparable to patient treatment scenarios. A solid water phantom irradiated with a 6 MV photon beam was imaged by the cameras to evaluate the maximum frame rate for adequate Cherenkov detection. Adequate detection was defined as an average electron count in the background-subtracted Cherenkov image region of interest in excess of 0.5% (327 counts) of the 16-bit maximum electron count value. Additionally, an ICCD and an EM-ICCD were each used clinically to image two patients undergoing whole-breast radiotherapy to compare clinical advantages and limitations of each system. Results: Intensifier-coupled cameras were required for imaging Cherenkov emission on the phantom surface with ambient room lighting; standalone CMOS and CCD cameras were not viable. The EM-ICCD was able to collect images from a single Linac pulse delivering less than 0.05 cGy of dose at 30 frames/s (fps) and pixel resolution of 512 × 512, compared to an ICCD which was limited to 4.7 fps at 1024 × 1024 resolution. An intensifier with higher quantum efficiency at the entrance photocathode in the red wavelengths [30% quantum efficiency (QE) vs previous 19%] promises at least 8.6 fps at a resolution of 1024 × 1024 and lower monetary

  5. Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging

    PubMed Central

    Andreozzi, Jacqueline M.; Zhang, Rongxiao; Glaser, Adam K.; Jarvis, Lesley A.; Pogue, Brian W.; Gladstone, David J.

    2015-01-01

    Purpose: To identify achievable camera performance and hardware needs in a clinical Cherenkov imaging system for real-time, in vivo monitoring of the surface beam profile on patients, as novel visual information, documentation, and possible treatment verification for clinicians. Methods: Complementary metal-oxide-semiconductor (CMOS), charge-coupled device (CCD), intensified charge-coupled device (ICCD), and electron multiplying-intensified charge coupled device (EM-ICCD) cameras were investigated to determine Cherenkov imaging performance in a clinical radiotherapy setting, with one emphasis on the maximum supportable frame rate. Where possible, the image intensifier was synchronized using a pulse signal from the Linac in order to image with room lighting conditions comparable to patient treatment scenarios. A solid water phantom irradiated with a 6 MV photon beam was imaged by the cameras to evaluate the maximum frame rate for adequate Cherenkov detection. Adequate detection was defined as an average electron count in the background-subtracted Cherenkov image region of interest in excess of 0.5% (327 counts) of the 16-bit maximum electron count value. Additionally, an ICCD and an EM-ICCD were each used clinically to image two patients undergoing whole-breast radiotherapy to compare clinical advantages and limitations of each system. Results: Intensifier-coupled cameras were required for imaging Cherenkov emission on the phantom surface with ambient room lighting; standalone CMOS and CCD cameras were not viable. The EM-ICCD was able to collect images from a single Linac pulse delivering less than 0.05 cGy of dose at 30 frames/s (fps) and pixel resolution of 512 × 512, compared to an ICCD which was limited to 4.7 fps at 1024 × 1024 resolution. An intensifier with higher quantum efficiency at the entrance photocathode in the red wavelengths [30% quantum efficiency (QE) vs previous 19%] promises at least 8.6 fps at a resolution of 1024 × 1024 and lower monetary

  6. Skin hydration imaging using a long-wavelength near-infrared digital camera

    NASA Astrophysics Data System (ADS)

    Attas, E. Michael; Posthumus, Trevor B.; Schattka, Bernhard J.; Sowa, Michael G.; Mantsch, Henry H.; Zhang, Shuliang L.

    2001-07-01

    Skin hydration is a key factor in skin health. Hydration measurements can provide diagnostic information on the condition of skin and can indicate the integrity of the skin barrier function. Near-infrared spectroscopy measures the water content of living tissue by its effect on tissue reflectance at a particular wavelength. Imaging has the important advantage of showing the degree of hydration as a function of location. Short-wavelength (650-1050 nm) near infrared spectroscopic reflectance imaging has previously been used in-vivo to determine the relative water content of skin under carefully controlled laboratory conditions. We have recently developed a novel spectroscopic imaging system to acquire image sets in the long-wavelength region of the near infrared (960 to 1700 nm), where the water absorption bands are more intense. The LW-NIR systems uses a liquid- crystal tunable filter in front of the objective lens and incorporates a 12-bit digital camera with a 320-by-240-pixel indium-gallium arsenide array sensor. Custom software controls the camera and tunable filter, allowing image sets to be acquired and displayed in near-real time. Forearm skin hydration was measured in a clinical context using the long- wavelength imaging system, a short-wavelength imaging system, and non-imaging instrumentation. Among these, the LW-NIR system appears to be the most sensitive at measuring dehydration of skin.

  7. Single camera system for multi-wavelength fluorescent imaging in the heart.

    PubMed

    Yamanaka, Takeshi; Arafune, Tatsuhiko; Shibata, Nitaro; Honjo, Haruo; Kamiya, Kaichiro; Kodama, Itsuo; Sakuma, Ichiro

    2012-01-01

    Optical mapping has been a powerful method to measure the cardiac electrophysiological phenomenon such as membrane potential(V(m)), intracellular calcium(Ca(2+)), and the other electrophysiological parameters. To measure two parameters simultaneously, the dual mapping system using two cameras is often used. However, the method to measure more than three parameters does not exist. To exploit the full potential of fluorescence imaging, an innovative method to measure multiple, more than three parameters is needed. In this study, we present a new optical mapping system which records multiple parameters using a single camera. Our system consists of one camera, custom-made optical lens units, and a custom-made filter wheel. The optical lens units is designed to focus the fluorescence light at filter position, and form an image on camera's sensor. To obtain optical signals with high quality, efficiency of light collection was carefully discussed in designing the optical system. The developed optical system has object space numerical aperture(NA) 0.1, and image space NA 0.23. The filter wheel was rotated by a motor, which allows filter switching corresponding with needed fluorescence wavelength. The camera exposure and filter switching were synchronized by phase locked loop, which allow this system to record multiple fluorescent signals frame by frame alternately. To validate the performance of this system, we performed experiments to observe V(m) and Ca(2+) dynamics simultaneously (frame rate: 125fps) with Langendorff perfused rabbit heart. Firstly, we applied basic stimuli to the heart base (cycle length: 500ms), and observed planer wave. The waveforms of V(m) and Ca(2+) show the same upstroke synchronized with cycle length of pacing. In addition, we recorded V(m) and Ca(2+) signals during ventricular fibrillation induced by burst pacing. According to these experiments, we showed the efficacy and availability of our method for cardiac electrophysiological research. PMID

  8. Real-time analysis of laser beams by simultaneous imaging on a single camera chip

    NASA Astrophysics Data System (ADS)

    Piehler, S.; Boley, M.; Abdou Ahmed, M.; Graf, T.

    2015-03-01

    The fundamental parameters of a laser beam, such as the exact position and size of the focus or the beam quality factor M² yield vital information both for laser developers and end-users. However, each of these parameters can significantly change on a short time scale due to thermally induced effects in the processing optics or in the laser source itself, leading to process instabilities and non-reproducible results. In order to monitor the transient behavior of these effects, we have developed a camera-based measurement system, which enables full laser beam characterization in online. A novel monolithic beam splitter has been designed which generates a 2D array of images on a single camera chip, each of which corresponds to an intensity cross section of the beam along the propagation axis separated by a well-defined spacing. Thus, using the full area of the camera chip, a large number of measurement planes is achieved, leading to a measurement range sufficient for a full beam characterization conforming to ISO 11146 for a broad range of beam parameters of the incoming beam. The exact beam diameters in each plane are derived by calculation of the 2nd order intensity moments of the individual intensity slices. The processing time needed to carry out both the background filtering and the image processing operations for the full analysis of a single camera image is in the range of a few milliseconds. Hence, the measurement frequency of our system is mainly limited by the frame-rate of the camera.

  9. IR camera temperature resolution enhancing using computer processing of IR image

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Trofimov, Vladislav V.

    2016-05-01

    As it is well-known, application of the IR camera for the security problems is very promising way. In previous papers, we demonstrate new possibility of the passive THz camera using for a temperature difference observing on the human skin if this difference is caused by different temperatures inside the body. For proof of validity of our statement we make the similar physical experiment using the IR camera. We show a possility of viewing the temperature trace on a human body skin, caused by temperature changing inside the human body due to water drinking. We use new approach, based on usung a correlation function, for computer processing of IR images. Its application results in a temperature resolution enhancing of cameras. We analyze IR images of a person, which drinks water. We follow a temperature trace on human body skin, caused by changing of temperature inside the human body. Some experiments were made with measurements of a body temperature covered by shirt. We try to see a human body temperature changing in physical experiments under consideration. Shown phenomena are very important for the detection of forbidden objects, cancelled under clothes or inside the human body, by using non-destructive control without using X-rays.

  10. Portable, stand-off spectral imaging camera for detection of effluents and residues

    NASA Astrophysics Data System (ADS)

    Goldstein, Neil; St. Peter, Benjamin; Grot, Jonathan; Kogan, Michael; Fox, Marsha; Vujkovic-Cvijin, Pajo; Penny, Ryan; Cline, Jason

    2015-06-01

    A new, compact and portable spectral imaging camera, employing a MEMs-based encoded imaging approach, has been built and demonstrated for detection of hazardous contaminants including gaseous effluents and solid-liquid residues on surfaces. The camera is called the Thermal infrared Reconfigurable Analysis Camera for Effluents and Residues (TRACER). TRACER operates in the long wave infrared and has the potential to detect a wide variety of materials with characteristic spectral signatures in that region. The 30 lb. camera is tripod mounted and battery powered. A touch screen control panel provides a simple user interface for most operations. The MEMS spatial light modulator is a Texas Instruments Digital Microarray Array with custom electronics and firmware control. Simultaneous 1D-spatial and 1Dspectral dimensions are collected, with the second spatial dimension obtained by scanning the internal spectrometer slit. The sensor can be configured to collect data in several modes including full hyperspectral imagery using Hadamard multiplexing, panchromatic thermal imagery, and chemical-specific contrast imagery, switched with simple user commands. Matched filters and other analog filters can be generated internally on-the-fly and applied in hardware, substantially reducing detection time and improving SNR over HSI software processing, while reducing storage requirements. Results of preliminary instrument evaluation and measurements of flame exhaust are presented.

  11. Optimal design of anger camera for bremsstrahlung imaging: monte carlo evaluation.

    PubMed

    Walrand, Stephan; Hesse, Michel; Wojcik, Randy; Lhommel, Renaud; Jamar, François

    2014-01-01

    A conventional Anger camera is not adapted to bremsstrahlung imaging and, as a result, even using a reduced energy acquisition window, geometric x-rays represent <15% of the recorded events. This increases noise, limits the contrast, and reduces the quantification accuracy. Monte Carlo (MC) simulations of energy spectra showed that a camera based on a 30-mm-thick BGO crystal and equipped with a high energy pinhole collimator is well-adapted to bremsstrahlung imaging. The total scatter contamination is reduced by a factor 10 versus a conventional NaI camera equipped with a high energy parallel hole collimator enabling acquisition using an extended energy window ranging from 50 to 350 keV. By using the recorded event energy in the reconstruction method, shorter acquisition time and reduced orbit range will be usable allowing the design of a simplified mobile gantry. This is more convenient for use in a busy catheterization room. After injecting a safe activity, a fast single photon emission computed tomography could be performed without moving the catheter tip in order to assess the liver dosimetry and estimate the additional safe activity that could still be injected. Further long running time MC simulations of realistic acquisitions will allow assessing the quantification capability of such system. Simultaneously, a dedicated bremsstrahlung prototype camera reusing PMT-BGO blocks coming from a retired PET system is currently under design for further evaluation. PMID:24982849

  12. Optimal Design of Anger Camera for Bremsstrahlung Imaging: Monte Carlo Evaluation

    PubMed Central

    Walrand, Stephan; Hesse, Michel; Wojcik, Randy; Lhommel, Renaud; Jamar, François

    2014-01-01

    A conventional Anger camera is not adapted to bremsstrahlung imaging and, as a result, even using a reduced energy acquisition window, geometric x-rays represent <15% of the recorded events. This increases noise, limits the contrast, and reduces the quantification accuracy. Monte Carlo (MC) simulations of energy spectra showed that a camera based on a 30-mm-thick BGO crystal and equipped with a high energy pinhole collimator is well-adapted to bremsstrahlung imaging. The total scatter contamination is reduced by a factor 10 versus a conventional NaI camera equipped with a high energy parallel hole collimator enabling acquisition using an extended energy window ranging from 50 to 350 keV. By using the recorded event energy in the reconstruction method, shorter acquisition time and reduced orbit range will be usable allowing the design of a simplified mobile gantry. This is more convenient for use in a busy catheterization room. After injecting a safe activity, a fast single photon emission computed tomography could be performed without moving the catheter tip in order to assess the liver dosimetry and estimate the additional safe activity that could still be injected. Further long running time MC simulations of realistic acquisitions will allow assessing the quantification capability of such system. Simultaneously, a dedicated bremsstrahlung prototype camera reusing PMT–BGO blocks coming from a retired PET system is currently under design for further evaluation. PMID:24982849

  13. Influence of electron dose rate on electron counting images recorded with the K2 camera

    PubMed Central

    Li, Xueming; Zheng, Shawn Q.; Egami, Kiyoshi; Agard, David A.; Cheng, Yifan

    2013-01-01

    A recent technological breakthrough in electron cryomicroscopy (cryoEM) is the development of direct electron detection cameras for data acquisition. By bypassing the traditional phosphor scintillator and fiber optic coupling, these cameras have greatly enhanced sensitivity and detective quantum efficiency (DQE). Of the three currently available commercial cameras, the Gatan K2 Summit was designed specifically for counting individual electron events. Counting further enhances the DQE, allows for practical doubling of detector resolution and eliminates noise arising from the variable deposition of energy by each primary electron. While counting has many advantages, undercounting of electrons happens when more than one electron strikes the same area of the detector within the analog readout period (coincidence loss), which influences image quality. In this work, we characterized the K2 Summit in electron counting mode, and studied the relationship of dose rate and coincidence loss and its influence on the quality of counted images. We found that coincidence loss reduces low frequency amplitudes but has no significant influence on the signal-to-noise ratio of the recorded image. It also has little influence on high frequency signals. Images of frozen hydrated archaeal 20S proteasome (~700 kDa, D7 symmetry) recorded at the optimal dose rate retained both high-resolution signal and low-resolution contrast and enabled calculating a 3.6 Å three-dimensional reconstruction from only 10,000 particles. PMID:23968652

  14. Real-time depth controllable integral imaging pickup and reconstruction method with a light field camera.

    PubMed

    Jeong, Youngmo; Kim, Jonghyun; Yeom, Jiwoon; Lee, Chang-Kun; Lee, Byoungho

    2015-12-10

    In this paper, we develop a real-time depth controllable integral imaging system. With a high-frame-rate camera and a focus controllable lens, light fields from various depth ranges can be captured. According to the image plane of the light field camera, the objects in virtual and real space are recorded simultaneously. The captured light field information is converted to the elemental image in real time without pseudoscopic problems. In addition, we derive characteristics and limitations of the light field camera as a 3D broadcasting capturing device with precise geometry optics. With further analysis, the implemented system provides more accurate light fields than existing devices without depth distortion. We adapt an f-number matching method at the capture and display stage to record a more exact light field and solve depth distortion, respectively. The algorithm allows the users to adjust the pixel mapping structure of the reconstructed 3D image in real time. The proposed method presents a possibility of a handheld real-time 3D broadcasting system in a cheaper and more applicable way as compared to the previous methods. PMID:26836855

  15. Heart imaging by cadmium telluride gamma cameraEuropean Program ``BIOMED'' consortium

    NASA Astrophysics Data System (ADS)

    Scheiber, Ch.; Eclancher, B.; Chambron, J.; Prat, V.; Kazandjan, A.; Jahnke, A.; Matz, R.; Thomas, S.; Warren, S.; Hage-Hali, M.; Regal, R.; Siffert, P.; Karman, M.

    1999-06-01

    Cadmium telluride semiconductor detectors (CdTe) operating at room temperature are attractive for medical imaging because of their good energy resolution providing excellent spatial and contrast resolution. The compactness of the detection system allows the building of small light camera heads which can be used for bedside imaging. A mobile pixellated gamma camera based on 2304 CdTe (pixel size: 3×3 mm, field of view: 15 cm×15 cm) has been designed for cardiac imaging. A dedicated 16-channel integrated circuit has also been designed. The acquisition hardware is fully programmable (DSP card, personal computer-based system). Analytical calculations have shown that a commercial parrallel hole collimator will fit the efficiency/resolution requirements for cardiac applications. Monte-Carlo simulations predict that the Moire effect can be reduced by a 15° tilt of the collimator with respect to the detector grid. A 16×16 CdTe module has been built for the preliminary physical tests. The energy resolution was 6.16±0.6 keV (mean ± standard deviation, n=30). Uniformity was ±10%, improving to ±1% when using a correction table. Test objects (emission data: letters 1.8 mm in width) and cold rods in scatter medium have been acquired. The CdTe images have been compared to those acquired with a conventionnal gamma camera.

  16. New design of a gamma camera detector with reduced edge effect for breast imaging

    NASA Astrophysics Data System (ADS)

    Yeon Hwang, Ji; Lee, Seung-Jae; Baek, Cheol-Ha; Hyun Kim, Kwang; Hyun Chung, Yong

    2011-05-01

    In recent years, there has been a growing interest in developing small gamma cameras dedicated to breast imaging. We designed a new detector with trapezoidal shape to expand the field of view (FOV) of camera without increasing its dimensions. To find optimal parameters, images of point sources at the edge area as functions of the angle and optical treatment of crystal side surface were simulated by using a DETECT2000. Our detector employs monolithic CsI(Tl) with dimensions of 48.0×48.0×6.0 mm coupled to an array of photo-sensors. Side surfaces of crystal were treated with three different surface finishes: black absorber, metal reflector and white reflector. The trapezoidal angle varied from 45° to 90° in steps of 15°. Gamma events were generated on 15 evenly spaced points with 1.0 mm spacing in the X-axis starting 1.0 mm away from the side surface. Ten thousand gamma events were simulated at each location and images were formed by calculating the Anger-logic. The results demonstrated that all the 15 points could be identified only for the crystal with trapezoidal shape having 45° angle and white reflector on the side surface. In conclusion, our new detector proved to be a reliable design to expand the FOV of small gamma camera for breast imaging.

  17. First responder thermal imaging cameras: establishment of representative performance testing conditions

    NASA Astrophysics Data System (ADS)

    Amon, Francine; Hamins, Anthony; Rowe, Justin

    2006-04-01

    Thermal imaging cameras are rapidly becoming integral equipment for first responders for use in structure fires and other emergencies. Currently there are no standardized performance metrics or test methods available to the users and manufacturers of these instruments. The Building and Fire Research Laboratory (BFRL) at the National Institute of Standards and Technology is conducting research to establish test conditions that best represent the environment in which these cameras are used. First responders may use thermal imagers for field operations ranging from fire attack and search/rescue in burning structures, to hot spot detection in overhaul activities, to detecting the location of hazardous materials. In order to develop standardized performance metrics and test methods that capture the harsh environment in which these cameras may be used, information has been collected from the literature, and from full-scale tests that have been conducted at BFRL. Initial experimental work has focused on temperature extremes and the presence of obscuring media such as smoke. In full-scale tests, thermal imagers viewed a target through smoke, dust, and steam, with and without flames in the field of view. The fuels tested were hydrocarbons (methanol, heptane, propylene, toluene), wood, upholstered cushions, and carpeting with padding. Gas temperatures, CO, CO II, and O II volume fraction, emission spectra, and smoke concentrations were measured. Simple thermal bar targets and a heated mannequin fitted in firefighter gear were used as targets. The imagers were placed at three distances from the targets, ranging from 3 m to 12 m.

  18. High-resolution image digitizing through 12x3-bit RGB-filtered CCD camera

    NASA Astrophysics Data System (ADS)

    Cheng, Andrew Y. S.; Pau, Michael C. Y.

    1996-09-01

    A high resolution computer-controlled CCD image capturing system is developed by using a 12 bits 1024 by 1024 pixels CCD camera and motorized RGB filters to grasp an image with color depth up to 36 bits. The filters distinguish the major components of color and collect them separately while the CCD camera maintains the spatial resolution and detector filling factor. The color separation can be done optically rather than electronically. The operation is simply by placing the capturing objects like color photos, slides and even x-ray transparencies under the camera system, the necessary parameters such as integration time, mixing level and light intensity are automatically adjusted by an on-line expert system. This greatly reduces the restrictions of the capturing species. This unique approach can save considerable time for adjusting the quality of image, give much more flexibility of manipulating captured object even if it is a 3D object with minimal setup fixers. In addition, cross sectional dimension of a 3D capturing object can be analyzed by adapting a fiber optic ring light source. It is particularly useful in non-contact metrology of a 3D structure. The digitized information can be stored in an easily transferable format. Users can also perform a special LUT mapping automatically or manually. Applications of the system include medical images archiving, printing quality control, 3D machine vision, and etc.

  19. Estimating information from image colors: an application to digital cameras and natural scenes.

    PubMed

    Marín-Franch, Iván; Foster, David H

    2013-01-01

    The colors present in an image of a scene provide information about its constituent elements. But the amount of information depends on the imaging conditions and on how information is calculated. This work had two aims. The first was to derive explicitly estimators of the information available and the information retrieved from the color values at each point in images of a scene under different illuminations. The second was to apply these estimators to simulations of images obtained with five sets of sensors used in digital cameras and with the cone photoreceptors of the human eye. Estimates were obtained for 50 hyperspectral images of natural scenes under daylight illuminants with correlated color temperatures 4,000, 6,500, and 25,000 K. Depending on the sensor set, the mean estimated information available across images with the largest illumination difference varied from 15.5 to 18.0 bits and the mean estimated information retrieved after optimal linear processing varied from 13.2 to 15.5 bits (each about 85 percent of the corresponding information available). With the best sensor set, 390 percent more points could be identified per scene than with the worst. Capturing scene information from image colors depends crucially on the choice of camera sensors. PMID:22450817

  20. Real Time Speed Estimation of Moving Vehicles from Side View Images from an Uncalibrated Video Camera

    PubMed Central

    Doğan, Sedat; Temiz, Mahir Serhan; Külür, Sıtkı

    2010-01-01

    In order to estimate the speed of a moving vehicle with side view camera images, velocity vectors of a sufficient number of reference points identified on the vehicle must be found using frame images. This procedure involves two main steps. In the first step, a sufficient number of points from the vehicle is selected, and these points must be accurately tracked on at least two successive video frames. In the second step, by using the displacement vectors of the tracked points and passed time, the velocity vectors of those points are computed. Computed velocity vectors are defined in the video image coordinate system and displacement vectors are measured by the means of pixel units. Then the magnitudes of the computed vectors in image space should be transformed to the object space to find the absolute values of these magnitudes. This transformation requires an image to object space information in a mathematical sense that is achieved by means of the calibration and orientation parameters of the video frame images. This paper presents proposed solutions for the problems of using side view camera images mentioned here. PMID:22399909

  1. Technique for improving the quality of images from digital cameras using ink-jet printers and smoothed RGB transfer curves

    NASA Astrophysics Data System (ADS)

    Sampat, Nitin; Grim, John F.; O'Hara, James E.

    1998-04-01

    The digital camera market is growing at an explosive rate. At the same time, the quality of photographs printed on ink- jet printers continues to improve. Most of the consumer cameras are designed with the monitor as the target output device and ont the printer. When a user is printing his images from a camera, he/she needs to optimize the camera and printer combination in order to maximize image quality. We describe the details of one such method for improving image quality using a AGFA digital camera and an ink jet printer combination. Using Adobe PhotoShop, we generated optimum red, green and blue transfer curves that match the scene content to the printers output capabilities. Application of these curves to the original digital image resulted in a print with more shadow detail, no loss of highlight detail, a smoother tone scale, and more saturated colors. The image also exhibited an improved tonal scale and visually more pleasing images than those captured and printed without any 'correction'. While we report the results for one camera-printer combination we tested this technique on numbers digital cameras and printer combinations and in each case produced a better looking image. We also discuss the problems we encountered in implementing this technique.

  2. A curve fitting method for extrinsic camera calibration from a single image of a cylindrical object

    NASA Astrophysics Data System (ADS)

    Winkler, A. W.; Zagar, B. G.

    2013-08-01

    An important step in the process of optical steel coil quality assurance is to measure the proportions of width and radius of steel coils as well as the relative position and orientation of the camera. This work attempts to estimate these extrinsic parameters from single images by using the cylindrical coil itself as the calibration target. Therefore, an adaptive least-squares algorithm is applied to fit parametrized curves to the detected true coil outline in the acquisition. The employed model allows for strictly separating the intrinsic and the extrinsic parameters. Thus, the intrinsic camera parameters can be calibrated beforehand using available calibration software. Furthermore, a way to segment the true coil outline in the acquired images is motivated. The proposed optimization method yields highly accurate results and can be generalized even to measure other solids which cannot be characterized by the identification of simple geometric primitives.

  3. Visible–infrared achromatic imaging by wavefront coding with wide-angle automobile camera

    NASA Astrophysics Data System (ADS)

    Ohta, Mitsuhiko; Sakita, Koichi; Shimano, Takeshi; Sugiyama, Takashi; Shibasaki, Susumu

    2016-09-01

    We perform an experiment of achromatic imaging with wavefront coding (WFC) using a wide-angle automobile lens. Our original annular phase mask for WFC was inserted to the lens, for which the difference between the focal positions at 400 nm and at 950 nm is 0.10 mm. We acquired images of objects using a WFC camera with this lens under the conditions of visible and infrared light. As a result, the effect of the removal of the chromatic aberration of the WFC system was successfully determined. Moreover, we fabricated a demonstration set assuming the use of a night vision camera in an automobile and showed the effect of the WFC system.

  4. Optical character recognition of camera-captured images based on phase features

    NASA Astrophysics Data System (ADS)

    Diaz-Escobar, Julia; Kober, Vitaly

    2015-09-01

    Nowadays most of digital information is obtained using mobile devices specially smartphones. In particular, it brings the opportunity for optical character recognition in camera-captured images. For this reason many recognition applications have been recently developed such as recognition of license plates, business cards, receipts and street signal; document classification, augmented reality, language translator and so on. Camera-captured images are usually affected by geometric distortions, nonuniform illumination, shadow, noise, which make difficult the recognition task with existing systems. It is well known that the Fourier phase contains a lot of important information regardless of the Fourier magnitude. So, in this work we propose a phase-based recognition system exploiting phase-congruency features for illumination/scale invariance. The performance of the proposed system is tested in terms of miss classifications and false alarms with the help of computer simulation.

  5. Portable retinal imaging for eye disease screening using a consumer-grade digital camera

    NASA Astrophysics Data System (ADS)

    Barriga, Simon; Larichev, Andrey; Zamora, Gilberto; Soliz, Peter

    2012-03-01

    The development of affordable means to image the retina is an important step toward the implementation of eye disease screening programs. In this paper we present the i-RxCam, a low-cost, hand-held, retinal camera for widespread applications such as tele-retinal screening for eye diseases like diabetic retinopathy (DR), glaucoma, and age-related ocular diseases. Existing portable retinal imagers do not meet the requirements of a low-cost camera with sufficient technical capabilities (field of view, image quality, portability, battery power, and ease-of-use) to be distributed widely to low volume clinics, such as the offices of single primary care physicians serving rural communities. The i-RxCam uses a Nikon D3100 digital camera body. The camera has a CMOS sensor with 14.8 million pixels. We use a 50mm focal lens that gives a retinal field of view of 45 degrees. The internal autofocus can compensate for about 2D (diopters) of focusing error. The light source is an LED produced by Philips with a linear emitting area that is transformed using a light pipe to the optimal shape at the eye pupil, an annulus. To eliminate corneal reflex we use a polarization technique in which the light passes through a nano-wire polarizer plate. This is a novel type of polarizer featuring high polarization separation (contrast ratio of more than 1000) and very large acceptance angle (>45 degrees). The i-RxCam approach will yield a significantly more economical retinal imaging device that would allow mass screening of the at-risk population.

  6. Star-field identification algorithm. [for implementation on CCD-based imaging camera

    NASA Technical Reports Server (NTRS)

    Scholl, M. S.

    1993-01-01

    A description of a new star-field identification algorithm that is suitable for implementation on CCD-based imaging cameras is presented. The minimum identifiable star pattern element consists of an oriented star triplet defined by three stars, their celestial coordinates, and their visual magnitudes. The algorithm incorporates tolerance to faulty input data, errors in the reference catalog, and instrument-induced systematic errors.

  7. Volcano geodesy at Santiaguito using ground-based cameras and particle image velocimetry

    NASA Astrophysics Data System (ADS)

    Johnson, J.; Andrews, B. J.; Anderson, J.; Lyons, J. J.; Lees, J. M.

    2012-12-01

    The active Santiaguito dome in Guatemala is an exceptional field site for ground-based optical observations owing to the bird's-eye viewing perspective from neighboring Santa Maria Volcano. From the summit of Santa Maria the frequent (1 per hour) explosions and continuous lava flow effusion may be observed from a vantage point, which is at a ~30 degree elevation angle, 1200 m above and 2700 m distant from the active vent. At these distances both video cameras and SLR cameras fitted with high-power lenses can effectively track blocky features translating and uplifting on the surface of Santiaguito's dome. We employ particle image velocimetry in the spatial frequency domain to map movements of ~10x10 m^2 surface patches with better than 10 cm displacement resolution. During three field campaigns to Santiaguito in 2007, 2009, and 2012 we have used cameras to measure dome surface movements for a range of time scales. In 2007 and 2009 we used video cameras recording at 30 fps to track repeated rapid dome uplift (more than 1 m within 2 s) of the 30,000 m^2 dome associated with the onset of eruptive activity. We inferred that the these uplift events were responsible for both a seismic long period response and an infrasound bimodal pulse. In 2012 we returned to Santiaguito to quantify dome surface movements over hour-to-day-long time scales by recording time lapse imagery at one minute intervals. These longer time scales reveal dynamic structure to the uplift and subsidence trends, effusion rate, and surface flow patterns that are related to internal conduit pressurization. In 2012 we performed particle image velocimetry with multiple cameras spatially separated in order to reconstruct 3-dimensional surface movements.

  8. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    NASA Astrophysics Data System (ADS)

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-François; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-07-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  9. Intercomparison of SO2 camera systems for imaging volcanic gas plumes

    USGS Publications Warehouse

    Kern, Christoph; Lübcke, Peter; Bobrowski, Nicole; Campion, Robin; Mori, Toshiya; Smekens, Jean-Francois; Stebel, Kerstin; Tamburello, Giancarlo; Burton, Mike; Platt, Ulrich; Prata, Fred

    2015-01-01

    SO2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO2 cameras. In the first part of the experiment, the various technical designs are compared and the advantages and drawbacks of individual design options are considered. Though the ideal design was found to be dependent on the specific application, a number of general recommendations are made. Next, a time series of images recorded by all instruments at Stromboli Volcano (Italy) is compared. All instruments were easily able to capture SO2 clouds emitted from the summit vents. Quantitative comparison of the SO2 load in an individual cloud yielded an intra-instrument precision of about 12%. From the imagery, emission rates were then derived according to each group's standard retrieval process. A daily average SO2 emission rate of 61 ± 10 t/d was calculated. Due to differences in spatial integration methods and plume velocity determination, the time-dependent progression of SO2 emissions varied significantly among the individual systems. However, integration over distinct degassing events yielded comparable SO2 masses. Based on the intercomparison data, we find an approximate 1-sigma precision of 20% for the emission rates derived from the various SO2 cameras. Though it may still be improved in the future, this is currently within the typical accuracy of the measurement and is considered sufficient for most applications.

  10. Camera model and calibration process for high-accuracy digital image metrology of inspection planes

    NASA Astrophysics Data System (ADS)

    Correia, Bento A. B.; Dinis, Joao

    1998-10-01

    High accuracy digital image based metrology must rely on an integrated model of image generation that is able to consider simultaneously the geometry of the camera vs. object positioning, and the conversion of the optical image on the sensor into an electronic digital format. In applications of automated visual inspection involving the analysis of approximately plane objects these models are generally simplified in order to facilitate the process of camera calibration. In this context, the lack of rigor in the determination of the intrinsic parameters in such models is particularly relevant. Aiming at the high accuracy metrology of contours of objects lying on an analysis plane, and involving sub-pixel measurements, this paper presents a three-stage camera model that includes an extrinsic component of perspective distortion and the intrinsic components of radial lens distortion and sensor misalignment. The later two factors are crucial in applications of machine vision that rely on the use of low cost optical components. A polynomial model for the negative radial lens distortion of wide field of view CCTV lenses is also established.

  11. Validity and repeatability of a depth camera-based surface imaging system for thigh volume measurement.

    PubMed

    Bullas, Alice M; Choppin, Simon; Heller, Ben; Wheat, Jon

    2016-10-01

    Complex anthropometrics such as area and volume, can identify changes in body size and shape that are not detectable with traditional anthropometrics of lengths, breadths, skinfolds and girths. However, taking these complex with manual techniques (tape measurement and water displacement) is often unsuitable. Three-dimensional (3D) surface imaging systems are quick and accurate alternatives to manual techniques but their use is restricted by cost, complexity and limited access. We have developed a novel low-cost, accessible and portable 3D surface imaging system based on consumer depth cameras. The aim of this study was to determine the validity and repeatability of the system in the measurement of thigh volume. The thigh volumes of 36 participants were measured with the depth camera system and a high precision commercially available 3D surface imaging system (3dMD). The depth camera system used within this study is highly repeatable (technical error of measurement (TEM) of <1.0% intra-calibration and ~2.0% inter-calibration) but systematically overestimates (~6%) thigh volume when compared to the 3dMD system. This suggests poor agreement yet a close relationship, which once corrected can yield a usable thigh volume measurement. PMID:26928458

  12. Range camera calibration based on image sequences and dense comprehensive error statistics

    NASA Astrophysics Data System (ADS)

    Karel, Wilfried; Pfeifer, Norbert

    2009-01-01

    This article concentrates on the integrated self-calibration of both the interior orientation and the distance measurement system of a time-of-flght range camera (photonic mixer device). Unlike other approaches that investigate individual distortion factors separately, in the presented approach all calculations are based on the same data set that is captured without auxiliary devices serving as high-order reference, but with the camera being guided by hand. Flat, circular targets stuck on a planar whiteboard and with known positions are automatically tracked throughout the amplitude layer of long image sequences. These image observations are introduced into a bundle block adjustment, which on the one hand results in the determination of the interior orientation. Capitalizing the known planarity of the imaged board, the reconstructed exterior orientations furthermore allow for the derivation of reference values of the actual distance observations. Eased by the automatic reconstruction of the cameras trajectory and attitude, comprehensive statistics are generated, which are accumulated into a 5-dimensional matrix in order to be manageable. The marginal distributions of this matrix are inspected for the purpose of system identification, whereupon its elements are introduced into another least-squares adjustment, finally leading to clear range correction models and parameters.

  13. Digital image georeferencing from a multiple camera system by GPS/INS

    NASA Astrophysics Data System (ADS)

    Mostafa, Mohamed M. R.; Schwarz, Klaus-Peter

    In this paper, the development and testing of an airborne fully digital multi-sensor system for digital mapping data acquisition is presented. The system acquires two streams of data, namely, navigation (georeferencing) data and imaging data. The navigation data are obtained by integrating an accurate strapdown inertial navigation system with a differential GPS system (DGPS). The imaging data are acquired by two low-cost digital cameras, configured in such a way so as to reduce their geometric limitations. The two cameras capture strips of overlapping nadir and oblique images. The GPS/INS-derived trajectory contains the full translational and rotational motion of the carrier aircraft. Thus, image exterior orientation information is extracted from the trajectory, during post-processing. This approach eliminates the need for ground control (GCP) when computing 3D positions of objects that appear in the field of view of the system imaging component. Two approaches for calibrating the system are presented, namely, terrestrial calibration and in-flight calibration. Test flights were conducted over the campus of The University of Calgary. Testing the system showed that best ground point positioning accuracy at 1:12,000 average image scale is 0.2 m (RMS) in easting and northing and 0.3 m (RMS) in height. Preliminary results indicate that major applications of such a system in the future are in the field of digital mapping, at scales of 1:5000 and smaller, and in the generation of digital elevation models for engineering applications.

  14. Georeferencing airborne images from a multiple digital camera system by GPS/INS

    NASA Astrophysics Data System (ADS)

    Mostafa, Mohamed Mohamed Rashad

    2000-10-01

    In this thesis, the development and testing of an airborne fully digital multi-sensor system for kinematic mapping is presented. The system acquires two streams of data, namely navigation data and imaging data. The navigation data are obtained by integrating an accurate strapdown Inertial Navigation System with two GPS receivers. The imaging data are acquired by two digital cameras, configured in such a way so as to reduce their geometric limitations. The two digital cameras capture strips of overlapping nadir and oblique images. The INS/GPS-derived trajectory contains the full translational and rotational motion of the carrier aircraft. Thus, image exterior orientation information is extracted from the trajectory, during postprocessing. This approach eliminates the need for ground control when computing 3D positions of objects that appear in the field of view of the system imaging component. Test flights were conducted over the campus of The University of Calgary. Two approaches for calibrating the system are presented, namely pre-mission calibration and in-flight calibration. Testing the system in flight showed that best ground point positioning accuracy at 1:12000 average image scale is 0.2 m (RMS) in easting and northing and 0.3 m (RMS) in height. Preliminary results indicate that major applications of such a system in the future are in the field of digital mapping, at scales of 1:10000 and smaller, and the generation of digital elevation models for engineering applications.

  15. Imaging microscopic structures in pathological retinas using a flood-illumination adaptive optics retinal camera

    NASA Astrophysics Data System (ADS)

    Viard, Clément; Nakashima, Kiyoko; Lamory, Barbara; Pâques, Michel; Levecq, Xavier; Château, Nicolas

    2011-03-01

    This research is aimed at characterizing in vivo differences between healthy and pathological retinal tissues at the microscopic scale using a compact adaptive optics (AO) retinal camera. Tests were performed in 120 healthy eyes and 180 eyes suffering from 19 different pathological conditions, including age-related maculopathy (ARM), glaucoma and rare diseases such as inherited retinal dystrophies. Each patient was first examined using SD-OCT and infrared SLO. Retinal areas of 4°x4° were imaged using an AO flood-illumination retinal camera based on a large-stroke deformable mirror. Contrast was finally enhanced by registering and averaging rough images using classical algorithms. Cellular-resolution images could be obtained in most cases. In ARM, AO images revealed granular contents in drusen, which were invisible in SLO or OCT images, and allowed the observation of the cone mosaic between drusen. In glaucoma cases, visual field was correlated to changes in cone visibility. In inherited retinal dystrophies, AO helped to evaluate cone loss across the retina. Other microstructures, slightly larger in size than cones, were also visible in several retinas. AO provided potentially useful diagnostic and prognostic information in various diseases. In addition to cones, other microscopic structures revealed by AO images may also be of interest in monitoring retinal diseases.

  16. COMPACT CdZnTe-BASED GAMMA CAMERA FOR PROSTATE CANCER IMAGING

    SciTech Connect

    CUI, Y.; LALL, T.; TSUI, B.; YU, J.; MAHLER, G.; BOLOTNIKOV, A.; VASKA, P.; DeGERONIMO, G.; O'CONNOR, P.; MEINKEN, G.; JOYAL, J.; BARRETT, J.; CAMARDA, G.; HOSSAIN, A.; KIM, K.H.; YANG, G.; POMPER, M.; CHO, S.; WEISMAN, K.; SEO, Y.; BABICH, J.; LaFRANCE, N.; AND JAMES, R.B.

    2011-10-23

    In this paper, we discuss the design of a compact gamma camera for high-resolution prostate cancer imaging using Cadmium Zinc Telluride (CdZnTe or CZT) radiation detectors. Prostate cancer is a common disease in men. Nowadays, a blood test measuring the level of prostate specific antigen (PSA) is widely used for screening for the disease in males over 50, followed by (ultrasound) imaging-guided biopsy. However, PSA tests have a high false-positive rate and ultrasound-guided biopsy has a high likelihood of missing small cancerous tissues. Commercial methods of nuclear medical imaging, e.g. PET and SPECT, can functionally image the organs, and potentially find cancer tissues at early stages, but their applications in diagnosing prostate cancer has been limited by the smallness of the prostate gland and the long working distance between the organ and the detectors comprising these imaging systems. CZT is a semiconductor material with wide band-gap and relatively high electron mobility, and thus can operate at room temperature without additional cooling. CZT detectors are photon-electron direct-conversion devices, thus offering high energy-resolution in detecting gamma rays, enabling energy-resolved imaging, and reducing the background of Compton-scattering events. In addition, CZT material has high stopping power for gamma rays; for medical imaging, a few-mm-thick CZT material provides adequate detection efficiency for many SPECT radiotracers. Because of these advantages, CZT detectors are becoming popular for several SPECT medical-imaging applications. Most recently, we designed a compact gamma camera using CZT detectors coupled to an application-specific-integrated-circuit (ASIC). This camera functions as a trans-rectal probe to image the prostate gland from a distance of only 1-5 cm, thus offering higher detection efficiency and higher spatial resolution. Hence, it potentially can detect prostate cancers at their early stages. The performance tests of this camera

  17. Compact CdZnTe-based gamma camera for prostate cancer imaging

    NASA Astrophysics Data System (ADS)

    Cui, Yonggang; Lall, Terry; Tsui, Benjamin; Yu, Jianhua; Mahler, George; Bolotnikov, Aleksey; Vaska, Paul; De Geronimo, Gianluigi; O'Connor, Paul; Meinken, George; Joyal, John; Barrett, John; Camarda, Giuseppe; Hossain, Anwar; Kim, Ki Hyun; Yang, Ge; Pomper, Marty; Cho, Steve; Weisman, Ken; Seo, Youngho; Babich, John; LaFrance, Norman; James, Ralph B.

    2011-06-01

    In this paper, we discuss the design of a compact gamma camera for high-resolution prostate cancer imaging using Cadmium Zinc Telluride (CdZnTe or CZT) radiation detectors. Prostate cancer is a common disease in men. Nowadays, a blood test measuring the level of prostate specific antigen (PSA) is widely used for screening for the disease in males over 50, followed by (ultrasound) imaging-guided biopsy. However, PSA tests have a high falsepositive rate and ultrasound-guided biopsy has a high likelihood of missing small cancerous tissues. Commercial methods of nuclear medical imaging, e.g. PET and SPECT, can functionally image the organs, and potentially find cancer tissues at early stages, but their applications in diagnosing prostate cancer has been limited by the smallness of the prostate gland and the long working distance between the organ and the detectors comprising these imaging systems. CZT is a semiconductor material with wide band-gap and relatively high electron mobility, and thus can operate at room temperature without additional cooling. CZT detectors are photon-electron direct-conversion devices, thus offering high energy-resolution in detecting gamma rays, enabling energy-resolved imaging, and reducing the background of Compton-scattering events. In addition, CZT material has high stopping power for gamma rays; for medical imaging, a few-mm-thick CZT material provides adequate detection efficiency for many SPECT radiotracers. Because of these advantages, CZT detectors are becoming popular for several SPECT medical-imaging applications. Most recently, we designed a compact gamma camera using CZT detectors coupled to an application-specific-integratedcircuit (ASIC). This camera functions as a trans-rectal probe to image the prostate gland from a distance of only 1-5 cm, thus offering higher detection efficiency and higher spatial resolution. Hence, it potentially can detect prostate cancers at their early stages. The performance tests of this camera

  18. Diffuse reflection imaging of sub-epidermal tissue haematocrit using a simple RGB camera

    NASA Astrophysics Data System (ADS)

    Leahy, Martin J.; O'Doherty, Jim; McNamara, Paul; Henricson, Joakim; Nilsson, Gert E.; Anderson, Chris; Sjoberg, Folke

    2007-05-01

    This paper describes the design and evaluation of a novel easy to use, tissue viability imaging system (TiVi). The system is based on the methods of diffuse reflectance spectroscopy and polarization spectroscopy. The technique has been developed as an alternative to current imaging technology in the area of microcirculation imaging, most notably optical coherence tomography (OCT) and laser Doppler perfusion imaging (LDPI). The system is based on standard digital camera technology, and is sensitive to red blood cells (RBCs) in the microcirculation. Lack of clinical acceptance of both OCT and LDPI fuels the need for an objective, simple, reproducible and portable imaging method that can provide accurate measurements related to stimulus vasoactivity in the microvasculature. The limitations of these technologies are discussed in this paper. Uses of the Tissue Viability system include skin care products, drug development, and assessment spatial and temporal aspects of vasodilation (erythema) and vasoconstriction (blanching).

  19. Can We Trust the Use of Smartphone Cameras in Clinical Practice? Laypeople Assessment of Their Image Quality

    PubMed Central

    Boissin, Constance; Fleming, Julian; Wallis, Lee; Hasselberg, Marie

    2015-01-01

    Abstract Background: Smartphone cameras are rapidly being introduced in medical practice, among other devices for image-based teleconsultation. Little is known, however, about the actual quality of the images taken, which is the object of this study. Materials and Methods: A series of nonclinical objects (from three broad categories) were photographed by a professional photographer using three smartphones (iPhone® 4 [Apple, Cupertino, CA], Samsung [Suwon, Korea] Galaxy S2, and BlackBerry® 9800 [BlackBerry Ltd., Waterloo, ON, Canada]) and a digital camera (Canon [Tokyo, Japan] Mark II). In a Web survey a convenience sample of 60 laypeople “blind” to the types of camera assessed the quality of the photographs, individually and best overall. We then measured how each camera scored by object category and as a whole and whether a camera ranked best using a Mann–Whitney U test for 2×2 comparisons. Results: There were wide variations between and within categories in the quality assessments for all four cameras. The iPhone had the highest proportion of images individually evaluated as good, and it also ranked best for more objects compared with other cameras, including the digital one. The ratings of the Samsung or the BlackBerry smartphone did not significantly differ from those of the digital camera. Conclusions: Whereas one smartphone camera ranked best more often, all three smartphones obtained results at least as good as those of the digital camera. Smartphone cameras can be a substitute for digital cameras for the purposes of medical teleconsulation. PMID:26076033

  20. Development of a high-speed CT imaging system using EMCCD camera

    NASA Astrophysics Data System (ADS)

    Thacker, Samta C.; Yang, Kai; Packard, Nathan; Gaysinskiy, Valeriy; Burkett, George; Miller, Stuart; Boone, John M.; Nagarkar, Vivek

    2009-02-01

    The limitations of current CCD-based microCT X-ray imaging systems arise from two important factors. First, readout speeds are curtailed in order to minimize system read noise, which increases significantly with increasing readout rates. Second, the afterglow associated with commercial scintillator films can introduce image lag, leading to substantial artifacts in reconstructed images, especially when the detector is operated at several hundred frames/second (fps). For high speed imaging systems, high-speed readout electronics and fast scintillator films are required. This paper presents an approach to developing a high-speed CT detector based on a novel, back-thinned electron-multiplying CCD (EMCCD) coupled to various bright, high resolution, low afterglow films. The EMCCD camera, when operated in its binned mode, is capable of acquiring data at up to 300 fps with reduced imaging area. CsI:Tl,Eu and ZnSe:Te films, recently fabricated at RMD, apart from being bright, showed very good afterglow properties, favorable for high-speed imaging. Since ZnSe:Te films were brighter than CsI:Tl,Eu films, for preliminary experiments a ZnSe:Te film was coupled to an EMCCD camera at UC Davis Medical Center. A high-throughput tungsten anode X-ray generator was used, as the X-ray fluence from a mini- or micro-focus source would be insufficient to achieve high-speed imaging. A euthanized mouse held in a glass tube was rotated 360 degrees in less than 3 seconds, while radiographic images were recorded at various readout rates (up to 300 fps); images were reconstructed using a conventional Feldkamp cone-beam reconstruction algorithm. We have found that this system allows volumetric CT imaging of small animals in approximately two seconds at ~110 to 190 μm resolution, compared to several minutes at 160 μm resolution needed for the best current systems.

  1. Intraoperative Imaging Guidance for Sentinel Node Biopsy in Melanoma Using a Mobile Gamma Camera

    SciTech Connect

    Dengel, Lynn T; Judy, Patricia G; Petroni, Gina R; Smolkin, Mark E; Rehm, Patrice K; Majewski, Stan; Williams, Mark B

    2011-04-01

    The objective is to evaluate the sensitivity and clinical utility of intraoperative mobile gamma camera (MGC) imaging in sentinel lymph node biopsy (SLNB) in melanoma. The false-negative rate for SLNB for melanoma is approximately 17%, for which failure to identify the sentinel lymph node (SLN) is a major cause. Intraoperative imaging may aid in detection of SLN near the primary site, in ambiguous locations, and after excision of each SLN. The present pilot study reports outcomes with a prototype MGC designed for rapid intraoperative image acquisition. We hypothesized that intraoperative use of the MGC would be feasible and that sensitivity would be at least 90%. From April to September 2008, 20 patients underwent Tc99 sulfur colloid lymphoscintigraphy, and SLNB was performed with use of a conventional fixed gamma camera (FGC), and gamma probe followed by intraoperative MGC imaging. Sensitivity was calculated for each detection method. Intraoperative logistical challenges were scored. Cases in which MGC provided clinical benefit were recorded. Sensitivity for detecting SLN basins was 97% for the FGC and 90% for the MGC. A total of 46 SLN were identified: 32 (70%) were identified as distinct hot spots by preoperative FGC imaging, 31 (67%) by preoperative MGC imaging, and 43 (93%) by MGC imaging pre- or intraoperatively. The gamma probe identified 44 (96%) independent of MGC imaging. The MGC provided defined clinical benefit as an addition to standard practice in 5 (25%) of 20 patients. Mean score for MGC logistic feasibility was 2 on a scale of 1-9 (1 = best). Intraoperative MGC imaging provides additional information when standard techniques fail or are ambiguous. Sensitivity is 90% and can be increased. This pilot study has identified ways to improve the usefulness of an MGC for intraoperative imaging, which holds promise for reducing false negatives of SLNB for melanoma.

  2. Application of real-time single camera SLAM technology for image-guided targeting in neurosurgery

    NASA Astrophysics Data System (ADS)

    Chang, Yau-Zen; Hou, Jung-Fu; Tsao, Yi Hsiang; Lee, Shih-Tseng

    2012-10-01

    In this paper, we propose an application of augmented reality technology for targeting tumors or anatomical structures inside the skull. The application is a combination of the technologies of MonoSLAM (Single Camera Simultaneous Localization and Mapping) and computer graphics. A stereo vision system is developed to construct geometric data of human face for registration with CT images. Reliability and accuracy of the application is enhanced by the use of fiduciary markers fixed to the skull. The MonoSLAM keeps track of the current location of the camera with respect to an augmented reality (AR) marker using the extended Kalman filter. The fiduciary markers provide reference when the AR marker is invisible to the camera. Relationship between the markers on the face and the augmented reality marker is obtained by a registration procedure by the stereo vision system and is updated on-line. A commercially available Android based tablet PC equipped with a 320×240 front-facing camera was used for implementation. The system is able to provide a live view of the patient overlaid by the solid models of tumors or anatomical structures, as well as the missing part of the tool inside the skull.

  3. ROSA: A High-cadence, Synchronized Multi-camera Solar Imaging System

    NASA Astrophysics Data System (ADS)

    Christian, Damian Joseph; Jess, D. B.; Mahtioudakis, M.; Keenan, F. P.

    2011-05-01

    The Rapid Oscillations in the Solar Atmosphere (ROSA) instrument is a synchronized, six-camera high-cadence solar imaging instrument developed by Queen's University Belfast and recently commissioned at the Dunn Solar Telescope at the National Solar Observatory in Sunspot, New Mexico, USA, as a common-user instrument. Consisting of six 1k x 1k Peltier-cooled frame-transfer CCD cameras with very low noise (0.02 - 15 e/pixel/s), each ROSA camera is capable of full-chip readout speeds in excess of 30 Hz, and up to 200 Hz when the CCD is windowed. ROSA will allow for multi-wavelength studies of the solar atmosphere at a high temporal resolution. We will present the current instrument set-up and parameters, observing modes, and future plans, including a new high QE camera allowing 15 Hz for Halpha. Interested parties should see https://habu.pst.qub.ac.uk/groups/arcresearch/wiki/de502/ROSA.html

  4. Electron-tracking Compton gamma-ray camera for small animal and phantom imaging

    NASA Astrophysics Data System (ADS)

    Kabuki, Shigeto; Kimura, Hiroyuki; Amano, Hiroo; Nakamoto, Yuji; Kubo, Hidetoshi; Miuchi, Kentaro; Kurosawa, Shunsuke; Takahashi, Michiaki; Kawashima, Hidekazu; Ueda, Masashi; Okada, Tomohisa; Kubo, Atsushi; Kunieda, Etuso; Nakahara, Tadaki; Kohara, Ryota; Miyazaki, Osamu; Nakazawa, Tetsuo; Shirahata, Takashi; Yamamoto, Etsuji; Ogawa, Koichi; Togashi, Kaori; Saji, Hideo; Tanimori, Toru

    2010-11-01

    We have developed an electron-tracking Compton camera (ETCC) for medical use. Our ETCC has a wide energy dynamic range (200-1300 keV) and wide field of view (3 sr), and thus has potential for advanced medical use. To evaluate the ETCC, we imaged the head (brain) and bladder of mice that had been administered with F-18-FDG. We also imaged the head and thyroid gland of mice using double tracers of F-18-FDG and I-131 ions.

  5. Fast calculation of bokeh image structure in camera lenses with multiple aspheric surfaces

    NASA Astrophysics Data System (ADS)

    Sivokon, V. P.; Thorpe, M. D.

    2014-12-01

    Three different approaches to calculation of internal structure of bokeh image in camera lenses with two aspheric surfaces are analyzed and compared - the transfer function approach, the beam propagation approach and direct raytracing in an optical design software. The transfer function approach is the fastest and provides accurate results when peak-to-valley of mid-spatial frequency phase modulation induced at the lens exit pupil is below λ/10. Aspheric surfaces are shown to contribute to the bokeh structure differently increasing the complexity of bokeh image especially for offaxis bokeh.

  6. The core of the nearby S0 galaxy NGC 7457 imaged with the HST planetary camera

    NASA Technical Reports Server (NTRS)

    Lauer, Tod R.; Faber, S. M.; Holtzman, Jon A.; Baum, William A.; Currie, Douglas G.; Ewald, S. P.; Groth, Edward J.; Hester, J. Jeff; Kelsall, T.

    1991-01-01

    A brief analysis is presented of images of the nearby S0 galaxy NGC 7457 obtained with the HST Planetary Camera. While the galaxy remains unresolved with the HST, the images reveal that any core most likely has r(c) less than 0.052 arcsec. The light distribution is consistent with a gamma = -1.0 power law inward to the resolution limit, with a possible stellar nucleus with luminosity of 10 million solar. This result represents the first observation outside the Local Group of a galaxy nucleus at this spatial resolution, and it suggests that such small, high surface brightness cores may be common.

  7. ROPtool analysis of images acquired using a noncontact handheld fundus camera (Pictor)--a pilot study.

    PubMed

    Vickers, Laura A; Freedman, Sharon F; Wallace, David K; Prakalapakorn, S Grace

    2015-12-01

    The presence of plus disease is the primary indication for treatment of retinopathy of prematurity (ROP), but its diagnosis is subjective and prone to error. ROPtool is a semiautomated computer program that quantifies vascular tortuosity and dilation. Pictor is an FDA-approved, noncontact, handheld digital fundus camera. This pilot study evaluated ROPtool's ability to analyze high-quality Pictor images of premature infants and its accuracy in diagnosing plus disease compared to clinical examination. In our small sample of images, ROPtool could trace and identify the presence of plus disease with high accuracy. PMID:26691046

  8. The measurement of astronomical parallaxes with CCD imaging cameras on small telescopes

    SciTech Connect

    Ratcliff, S.J. ); Balonek, T.J. ); Marschall, L.A. ); DuPuy, D.L. ); Pennypacker, C.R. ); Verma, R. ); Alexov, A. ); Bonney, V. )

    1993-03-01

    Small telescopes equipped with charge-coupled device (CCD) imaging cameras are well suited to introductory laboratory exercises in positional astronomy (astrometry). An elegant example is the determination of the parallax of extraterrestrial objects, such as asteroids. For laboratory exercises suitable for introductory students, the astronomical hardware needs are relatively modest, and, under the best circumstances, the analysis requires little more than arithmetic and a microcomputer with image display capabilities. Results from the first such coordinated parallax observations of asteroids ever made are presented. In addition, procedures for several related experiments, involving single-site observations and/or parallaxes of earth-orbiting artificial satellites, are outlined.

  9. Digital Camera Calibration Using Images Taken from AN Unmanned Aerial Vehicle

    NASA Astrophysics Data System (ADS)

    Pérez, M.; Agüera, F.; Carvajal, F.

    2011-09-01

    For calibrating the camera, an accurate determination of the interior orientation parameters is needed. For more accurate results, the calibration images should be taken under conditions that are similar to the field samples. The aim of this work is the establishment of an efficient and accurate digital camera calibration method to be used in particular working conditions, as it can be found with our UAV (Unmanned Aerial Vehicle) photogrammetric projects. The UAV used in this work was md4-200 modelled by Microdrones. The microdrone is also equipped with a standard digital non- metric camera, the Pentax Optio A40 camera. To find out the interior orientation parameters of the digital camera, two calibration methods were done. A lab calibration based on a flat pattern and a field calibration were fulfilled. To carry out the calibration, Photomodeler Scanner software was used in both cases. The lab calibration process was completely automatic using a calibration grid. The focal length was fixed at widest angle and the network included a total of twelve images with± 90º roll angles. In order to develop the field calibration, a flight plan was programmed including a total of twelve images. In the same way as in the lab calibration, the focal length was fixed at widest angle. The field test used in the study was a flat surface located on the University of Almería campus and a set of 67 target points were placed. The calibration field area was 25 × 25 m approximately and the altitude flight over ground was 50 m. After the software processing, the camera calibration parameter values were obtained. The paper presents the process, the results and the accuracy of these calibration methods. The field calibration method reduced the final total error obtained in the previous lab calibration. Furthermore the overall RMSs obtained from both methods are similar. Therefore we will apply the field calibration results to all our photogrammetric projects in which the flight high

  10. Multi-acoustic lens design methodology for a low cost C-scan photoacoustic imaging camera

    NASA Astrophysics Data System (ADS)

    Chinni, Bhargava; Han, Zichao; Brown, Nicholas; Vallejo, Pedro; Jacobs, Tess; Knox, Wayne; Dogra, Vikram; Rao, Navalgund

    2016-03-01

    We have designed and implemented a novel acoustic lens based focusing technology into a prototype photoacoustic imaging camera. All photoacoustically generated waves from laser exposed absorbers within a small volume get focused simultaneously by the lens onto an image plane. We use a multi-element ultrasound transducer array to capture the focused photoacoustic signals. Acoustic lens eliminates the need for expensive data acquisition hardware systems, is faster compared to electronic focusing and enables real-time image reconstruction. Using this photoacoustic imaging camera, we have imaged more than 150 several centimeter size ex-vivo human prostate, kidney and thyroid specimens with a millimeter resolution for cancer detection. In this paper, we share our lens design strategy and how we evaluate the resulting quality metrics (on and off axis point spread function, depth of field and modulation transfer function) through simulation. An advanced toolbox in MATLAB was adapted and used for simulating a two-dimensional gridded model that incorporates realistic photoacoustic signal generation and acoustic wave propagation through the lens with medium properties defined on each grid point. Two dimensional point spread functions have been generated and compared with experiments to demonstrate the utility of our design strategy. Finally we present results from work in progress on the use of two lens system aimed at further improving some of the quality metrics of our system.

  11. Development of a Portable 3CCD Camera System for Multispectral Imaging of Biological Samples

    PubMed Central

    Lee, Hoyoung; Park, Soo Hyun; Noh, Sang Ha; Lim, Jongguk; Kim, Moon S.

    2014-01-01

    Recent studies have suggested the need for imaging devices capable of multispectral imaging beyond the visible region, to allow for quality and safety evaluations of agricultural commodities. Conventional multispectral imaging devices lack flexibility in spectral waveband selectivity for such applications. In this paper, a recently developed portable 3CCD camera with significant improvements over existing imaging devices is presented. A beam-splitter prism assembly for 3CCD was designed to accommodate three interference filters that can be easily changed for application-specific multispectral waveband selection in the 400 to 1000 nm region. We also designed and integrated electronic components on printed circuit boards with firmware programming, enabling parallel processing, synchronization, and independent control of the three CCD sensors, to ensure the transfer of data without significant delay or data loss due to buffering. The system can stream 30 frames (3-waveband images in each frame) per second. The potential utility of the 3CCD camera system was demonstrated in the laboratory for detecting defect spots on apples. PMID:25350510

  12. Development of a portable 3CCD camera system for multispectral imaging of biological samples.

    PubMed

    Lee, Hoyoung; Park, Soo Hyun; Noh, Sang Ha; Lim, Jongguk; Kim, Moon S

    2014-01-01

    Recent studies have suggested the need for imaging devices capable of multispectral imaging beyond the visible region, to allow for quality and safety evaluations of agricultural commodities. Conventional multispectral imaging devices lack flexibility in spectral waveband selectivity for such applications. In this paper, a recently developed portable 3CCD camera with significant improvements over existing imaging devices is presented. A beam-splitter prism assembly for 3CCD was designed to accommodate three interference filters that can be easily changed for application-specific multispectral waveband selection in the 400 to 1000 nm region. We also designed and integrated electronic components on printed circuit boards with firmware programming, enabling parallel processing, synchronization, and independent control of the three CCD sensors, to ensure the transfer of data without significant delay or data loss due to buffering. The system can stream 30 frames (3-waveband images in each frame) per second. The potential utility of the 3CCD camera system was demonstrated in the laboratory for detecting defect spots on apples. PMID:25350510

  13. Improvement of a snapshot spectroscopic retinal multi-aperture imaging camera

    NASA Astrophysics Data System (ADS)

    Lemaillet, Paul; Lompado, Art; Ramella-Roman, Jessica C.

    2009-02-01

    Measurement of oxygen saturation has proved to give important information about the eye health and the onset of eye pathologies such as Diabetic Retinopathy. Recently, we have presented a multi-aperture system enabling snapshot acquisition of human fundus images at six different wavelengths. In our setup a commercial fundus ophthalmoscope was interfaced with the multi-aperture system to acquire spectroscopic sensitive images of the retina vessel, thus enabling assessment of the oxygen saturation in the retina. Snapshot spectroscopic acquisition is meant to minimize the effects of eye movements. Higher measurement accuracy can be achieved by increasing the number of wavelengths at which the fundus images are taken. In this study we present an improvement of our setup by introducing an other multi-aperture camera that enables us to take snapshot images of the fundus at nine different wavelengths. Careful consideration is taken to improve image transfer by measuring the optical properties of the fundus camera used in the setup and modeling the optical train in Zemax.

  14. Evaluating the capability of time-of-flight cameras for accurately imaging a cyclically loaded beam

    NASA Astrophysics Data System (ADS)

    Lahamy, Hervé; Lichti, Derek; El-Badry, Mamdouh; Qi, Xiaojuan; Detchev, Ivan; Steward, Jeremy; Moravvej, Mohammad

    2015-05-01

    Time-of-flight cameras are used for diverse applications ranging from human-machine interfaces and gaming to robotics and earth topography. This paper aims at evaluating the capability of the Mesa Imaging SR4000 and the Microsoft Kinect 2.0 time-of-flight cameras for accurately imaging the top surface of a concrete beam subjected to fatigue loading in laboratory conditions. Whereas previous work has demonstrated the success of such sensors for measuring the response at point locations, the aim here is to measure the entire beam surface in support of the overall objective of evaluating the effectiveness of concrete beam reinforcement with steel fibre reinforced polymer sheets. After applying corrections for lens distortions to the data and differencing images over time to remove systematic errors due to internal scattering, the periodic deflections experienced by the beam have been estimated for the entire top surface of the beam and at witness plates attached. The results have been assessed by comparison with measurements from highly-accurate laser displacement transducers. This study concludes that both the Microsoft Kinect 2.0 and the Mesa Imaging SR4000s are capable of sensing a moving surface with sub-millimeter accuracy once the image distortions have been modeled and removed.

  15. Performance of CID camera X-ray imagers at NIF in a harsh neutron environment

    SciTech Connect

    Palmer, N. E.; Schneider, M. B.; Bell, P. M.; Piston, K. W.; Moody, J. D.; James, D. L.; Ness, R. A.; Haugh, M. J.; Lee, J. J.; Romano, E. D.

    2013-09-01

    Charge-injection devices (CIDs) are solid-state 2D imaging sensors similar to CCDs, but their distinct architecture makes CIDs more resistant to ionizing radiation.1–3 CID cameras have been used extensively for X-ray imaging at the OMEGA Laser Facility4,5 with neutron fluences at the sensor approaching 109 n/cm2 (DT, 14 MeV). A CID Camera X-ray Imager (CCXI) system has been designed and implemented at NIF that can be used as a rad-hard electronic-readout alternative for time-integrated X-ray imaging. This paper describes the design and implementation of the system, calibration of the sensor for X-rays in the 3 – 14 keV energy range, and preliminary data acquired on NIF shots over a range of neutron yields. The upper limit of neutron fluence at which CCXI can acquire useable images is ~ 108 n/cm2 and there are noise problems that need further improvement, but the sensor has proven to be very robust in surviving high yield shots (~ 1014 DT neutrons) with minimal damage.

  16. Determining 3D Flow Fields via Multi-camera Light Field Imaging

    PubMed Central

    Truscott, Tadd T.; Belden, Jesse; Nielson, Joseph R.; Daily, David J.; Thomson, Scott L.

    2013-01-01

    In the field of fluid mechanics, the resolution of computational schemes has outpaced experimental methods and widened the gap between predicted and observed phenomena in fluid flows. Thus, a need exists for an accessible method capable of resolving three-dimensional (3D) data sets for a range of problems. We present a novel technique for performing quantitative 3D imaging of many types of flow fields. The 3D technique enables investigation of complicated velocity fields and bubbly flows. Measurements of these types present a variety of challenges to the instrument. For instance, optically dense bubbly multiphase flows cannot be readily imaged by traditional, non-invasive flow measurement techniques due to the bubbles occluding optical access to the interior regions of the volume of interest. By using Light Field Imaging we are able to reparameterize images captured by an array of cameras to reconstruct a 3D volumetric map for every time instance, despite partial occlusions in the volume. The technique makes use of an algorithm known as synthetic aperture (SA) refocusing, whereby a 3D focal stack is generated by combining images from several cameras post-capture 1. Light Field Imaging allows for the capture of angular as well as spatial information about the light rays, and hence enables 3D scene reconstruction. Quantitative information can then be extracted from the 3D reconstructions using a variety of processing algorithms. In particular, we have developed measurement methods based on Light Field Imaging for performing 3D particle image velocimetry (PIV), extracting bubbles in a 3D field and tracking the boundary of a flickering flame. We present the fundamentals of the Light Field Imaging methodology in the context of our setup for performing 3DPIV of the airflow passing over a set of synthetic vocal folds, and show representative results from application of the technique to a bubble-entraining plunging jet. PMID:23486112

  17. Application of adaptive optics in retinal imaging: a quantitative and clinical comparison with standard cameras

    NASA Astrophysics Data System (ADS)

    Barriga, E. S.; Erry, G.; Yang, S.; Russell, S.; Raman, B.; Soliz, P.

    2005-04-01

    Aim: The objective of this project was to evaluate high resolution images from an adaptive optics retinal imager through comparisons with standard film-based and standard digital fundus imagers. Methods: A clinical prototype adaptive optics fundus imager (AOFI) was used to collect retinal images from subjects with various forms of retinopathy to determine whether improved visibility into the disease could be provided to the clinician. The AOFI achieves low-order correction of aberrations through a closed-loop wavefront sensor and an adaptive optics system. The remaining high-order aberrations are removed by direct deconvolution using the point spread function (PSF) or by blind deconvolution when the PSF is not available. An ophthalmologist compared the AOFI images with standard fundus images and provided a clinical evaluation of all the modalities and processing techniques. All images were also analyzed using a quantitative image quality index. Results: This system has been tested on three human subjects (one normal and two with retinopathy). In the diabetic patient vascular abnormalities were detected with the AOFI that cannot be resolved with the standard fundus camera. Very small features, such as the fine vascular structures on the optic disc and the individual nerve fiber bundles are easily resolved by the AOFI. Conclusion: This project demonstrated that adaptive optic images have great potential in providing clinically significant detail of anatomical and pathological structures to the ophthalmologist.

  18. 200 ps FWHM and 100 MHz repetition rate ultrafast gated camera for optical medical functional imaging

    NASA Astrophysics Data System (ADS)

    Uhring, Wilfried; Poulet, Patrick; Hanselmann, Walter; Glazenborg, René; Zint, Virginie; Nouizi, Farouk; Dubois, Benoit; Hirschi, Werner

    2012-04-01

    The paper describes the realization of a complete optical imaging device to clinical applications like brain functional imaging by time-resolved, spectroscopic diffuse optical tomography. The entire instrument is assembled in a unique setup that includes a light source, an ultrafast time-gated intensified camera and all the electronic control units. The light source is composed of four near infrared laser diodes driven by a nanosecond electrical pulse generator working in a sequential mode at a repetition rate of 100 MHz. The resulting light pulses, at four wavelengths, are less than 80 ps FWHM. They are injected in a four-furcated optical fiber ended with a frontal light distributor to obtain a uniform illumination spot directed towards the head of the patient. Photons back-scattered by the subject are detected by the intensified CCD camera; there are resolved according to their time of flight inside the head. The very core of the intensified camera system is the image intensifier tube and its associated electrical pulse generator. The ultrafast generator produces 50 V pulses, at a repetition rate of 100 MHz and a width corresponding to the 200 ps requested gate. The photocathode and the Micro-Channel-Plate of the intensifier have been specially designed to enhance the electromagnetic wave propagation and reduce the power loss and heat that are prejudicial to the quality of the image. The whole instrumentation system is controlled by an FPGA based module. The timing of the light pulses and the photocathode gating is precisely adjustable with a step of 9 ps. All the acquisition parameters are configurable via software through an USB plug and the image data are transferred to a PC via an Ethernet link. The compactness of the device makes it a perfect device for bedside clinical applications.

  19. Linearisation of RGB Camera Responses for Quantitative Image Analysis of Visible and UV Photography: A Comparison of Two Techniques

    PubMed Central

    Garcia, Jair E.; Dyer, Adrian G.; Greentree, Andrew D.; Spring, Gale; Wilksch, Philip A.

    2013-01-01

    Linear camera responses are required for recovering the total amount of incident irradiance, quantitative image analysis, spectral reconstruction from camera responses and characterisation of spectral sensitivity curves. Two commercially-available digital cameras equipped with Bayer filter arrays and sensitive to visible and near-UV radiation were characterised using biexponential and Bézier curves. Both methods successfully fitted the entire characteristic curve of the tested devices, allowing for an accurate recovery of linear camera responses, particularly those corresponding to the middle of the exposure range. Nevertheless the two methods differ in the nature of the required input parameters and the uncertainty associated with the recovered linear camera responses obtained at the extreme ends of the exposure range. Here we demonstrate the use of both methods for retrieving information about scene irradiance, describing and quantifying the uncertainty involved in the estimation of linear camera responses. PMID:24260244

  20. Spartan infrared camera: high-resolution imaging for the SOAR Telescope

    NASA Astrophysics Data System (ADS)

    Loh, Edwin D.; Biel, Jason D.; Chen, Jian-Jun; Davis, Michael; Laporte, Rene; Loh, Owen Y.

    2004-09-01

    The Spartan Infrared Camera provides tip-tilt corrected imaging for the SOAR Telescope in the 1-2.5μm spectral range with four 2048x2048 HAWAII2 detectors. The median image size is expected to be less than 0.25 arcsec (FWHM), and in the H and K bands a significant amount of the light is expected to be in a core having the diffraction-limited width. The camera has two plate scales: 0.04 arcsec/pixel (f/21) for diffraction-limited sampling in the H and K bands and 0.07 arcsec/pixel (f/12) to cover a 5×5 arcmin2 field, over which tip-tilt correction is substantial. Except for CaF2 field-flattening lenses, the optics is all reflective to achieve the large field size and achromaticity, and all aluminum to match thermally the aluminum cryogenic-optical box in which the optics mount. The Strehl ratio of the camera itself is 0.95-1.00 for the f/21 channel. The optics (including the off-axis aspherical mirrors) will be aligned with precise metrology rather than adjusted using interferometry.

  1. Algorithm design for automated transportation photo enforcement camera image and video quality diagnostic check modules

    NASA Astrophysics Data System (ADS)

    Raghavan, Ajay; Saha, Bhaskar

    2013-03-01

    Photo enforcement devices for traffic rules such as red lights, toll, stops, and speed limits are increasingly being deployed in cities and counties around the world to ensure smooth traffic flow and public safety. These are typically unattended fielded systems, and so it is important to periodically check them for potential image/video quality problems that might interfere with their intended functionality. There is interest in automating such checks to reduce the operational overhead and human error involved in manually checking large camera device fleets. Examples of problems affecting such camera devices include exposure issues, focus drifts, obstructions, misalignment, download errors, and motion blur. Furthermore, in some cases, in addition to the sub-algorithms for individual problems, one also has to carefully design the overall algorithm and logic to check for and accurately classifying these individual problems. Some of these issues can occur in tandem or have the potential to be confused for each other by automated algorithms. Examples include camera misalignment that can cause some scene elements to go out of focus for wide-area scenes or download errors that can be misinterpreted as an obstruction. Therefore, the sequence in which the sub-algorithms are utilized is also important. This paper presents an overview of these problems along with no-reference and reduced reference image and video quality solutions to detect and classify such faults.

  2. A Gaseous Compton Camera using a 2D-sensitive gaseous photomultiplier for Nuclear Medical Imaging

    NASA Astrophysics Data System (ADS)

    Azevedo, C. D. R.; Pereira, F. A.; Lopes, T.; Correia, P. M. M.; Silva, A. L. M.; Carramate, L. F. N. D.; Covita, D. S.; Veloso, J. F. C. A.

    2013-12-01

    A new Compton Camera (CC) concept based on a High Pressure Scintillation Chamber coupled to a position-sensitive Gaseous PhotoMultiplier for Nuclear Medical Imaging applications is proposed. The main goal of this work is to describe the development of a ϕ25×12 cm3 cylindrical prototype, which will be suitable for scintimammography and for small-animal imaging applications. The possibility to scale it to an useful human size device is also in study. The idea is to develop a device capable to compete with the standard Anger Camera. Despite the large success of the Anger Camera, it still presents some limitations, such as: low position resolution and fair energy resolutions for 140 keV. The CC arises a different solution as it provides information about the incoming photon direction, avoiding the use of a collimator, which is responsible for a huge reduction (10-4) of the sensitivity. The main problem of the CC's is related with the Doppler Broadening which is responsible for the loss of angular resolution. In this work, calculations for the Doppler Broadening in Xe, Ar, Ne and their mixtures are presented. Simulations of the detector performance together with discussion about the gas choice are also included .

  3. An energy-subtraction Compton scatter camera design for in vivo medical imaging of radiopharmaceuticals

    SciTech Connect

    Rohe, R.C.; Valentine, J.D.

    1996-12-01

    A Compton scatter camera (CSC) design is proposed for imaging radioisotopes used as biotracers. A clinical version may increase sensitivity by a factor of over 100, while maintaining or improving spatial resolution, as compared with existing Anger cameras that use lead collimators. This novel approach is based on using energy subtraction ({Delta}E = E{sub 0} {minus} E{sub SC}, where E{sub 0}, {Delta}E, and E{sub SC} are the energy of the emitted gamma ray, the energy deposited by the initial Compton scatter, and the energy of the Compton scattered photon) to determine the amount of energy deposited in the primary system. The energy subtraction approach allows the requirement of high energy resolution to be placed on a secondary detector system instead of the primary detector system. Requiring primary system high energy resolution has significantly limited previous CSC designs for medical imaging applications. Furthermore, this approach is dependent on optimizing the camera design for data acquisition of gamma rays that undergo only one Compton scatter in a low-Z primary detector system followed by a total absorption of the Compton scattered photon in a high-Z secondary detector system. The proposed approach allows for a more compact primary detector system, a more simplified pulse processing interface, and a much less complicated detector cooling scheme as compared with previous CSC designs. Analytical calculations and Monte Carlo simulation results for some specific detector materials and geometries are presented.

  4. Line-based camera calibration with lens distortion correction from a single image

    NASA Astrophysics Data System (ADS)

    Zhou, Fuqiang; Cui, Yi; Gao, He; Wang, Yexin

    2013-12-01

    Camera calibration is a fundamental and important step in many machine vision applications. For some practical situations, computing camera parameters from merely a single image is becoming increasingly feasible and significant. However, the existing single view based calibration methods have various disadvantages such as ignoring lens distortion, requiring some prior knowledge or special calibration environment, and so on. To address these issues, we propose a line-based camera calibration method with lens distortion correction from a single image using three squares with unknown length. Initially, the radial distortion coefficients are obtained through a non-linear optimization process which is isolated from the pin-hole model calibration, and the detected distorted lines of all the squares are corrected simultaneously. Subsequently, the corresponding lines used for homography estimation are normalized to avoid the specific unstable case, and the intrinsic parameters are calculated from the sufficient restrictions provided by vectors of homography matrix. To evaluate the performance of the proposed method, both simulative and real experiments have been carried out and the results show that the proposed method is robust under general conditions and it achieves comparable measurement accuracy in contrast with the traditional multiple view based calibration method using 2D chessboard target.

  5. Optical streak camera images of wire-array z-pinches on the 1-MA COBRA pulsed power generator

    NASA Astrophysics Data System (ADS)

    McBride, Ryan; Pikuz, Sergei; Blesener, Isaac; Zhao, Yu Tao; Greenly, John; Hammer, David; Kusse, Bruce

    2006-10-01

    Initial optical streak camera imaging experiments of wire array z-pinches on the 1 MA COBRA pulsed power generator are presented. The imaging system makes use of a Hamamatsu C7700 streak unit, which is coupled to a V7669-06 image intensifier with an MCP, and a C4742-98 CCD camera. A long focal length optical system is employed to relay the z-pinch produced light from the experiment chamber to the input slit of the streak camera -- a total transmission distance of approximately 14 m. The optical streak camera images produced, along with data from other supporting diagnostics, are presented for z-pinch implosions of various wire array geometries and materials.

  6. Characterization of digital cameras for reflected ultraviolet photography; implications for qualitative and quantitative image analysis during forensic examination.

    PubMed

    Garcia, Jair E; Wilksch, Philip A; Spring, Gale; Philp, Peta; Dyer, Adrian

    2014-01-01

    Reflected ultraviolet imaging techniques allow for the visualization of evidence normally outside the human visible spectrum. Specialized digital cameras possessing extended sensitivity can be used for recording reflected ultraviolet radiation. Currently, there is a lack of standardized methods for ultraviolet image recording and processing using digital cameras, potentially limiting the implementation and interpretation. A methodology is presented for processing ultraviolet images based on linear responses and the sensitivity of the respective color channels. The methodology is applied to a FujiS3 UVIR camera, and a modified Nikon D70s camera, to reconstruct their respective spectral sensitivity curves between 320 and 400 nm. This method results in images with low noise and high contrast, suitable for qualitative and/or quantitative analysis. The application of this methodology is demonstrated in the recording of latent fingerprints. PMID:24117678

  7. Image Capture with Synchronized Multiple-Cameras for Extraction of Accurate Geometries

    NASA Astrophysics Data System (ADS)

    Koehl, M.; Delacourt, T.; Boutry, C.

    2016-06-01

    This paper presents a project of recording and modelling tunnels, traffic circles and roads from multiple sensors. The aim is the representation and the accurate 3D modelling of a selection of road infrastructures as dense point clouds in order to extract profiles and metrics from it. Indeed, these models will be used for the sizing of infrastructures in order to simulate exceptional convoy truck routes. The objective is to extract directly from the point clouds the heights, widths and lengths of bridges and tunnels, the diameter of gyrating and to highlight potential obstacles for a convoy. Light, mobile and fast acquisition approaches based on images and videos from a set of synchronized sensors have been tested in order to obtain useable point clouds. The presented solution is based on a combination of multiple low-cost cameras designed on an on-boarded device allowing dynamic captures. The experimental device containing GoPro Hero4 cameras has been set up and used for tests in static or mobile acquisitions. That way, various configurations have been tested by using multiple synchronized cameras. These configurations are discussed in order to highlight the best operational configuration according to the shape of the acquired objects. As the precise calibration of each sensor and its optics are major factors in the process of creation of accurate dense point clouds, and in order to reach the best quality available from such cameras, the estimation of the internal parameters of fisheye lenses of the cameras has been processed. Reference measures were also realized by using a 3D TLS (Faro Focus 3D) to allow the accuracy assessment.

  8. Measuring SO2 ship emissions with an ultra-violet imaging camera

    NASA Astrophysics Data System (ADS)

    Prata, A. J.

    2013-11-01

    Over the last few years fast-sampling ultra-violet (UV) imaging cameras have been developed for use in measuring SO2 emissions from industrial sources (e.g. power plants; typical fluxes ~1-10 kg s-1) and natural sources (e.g. volcanoes; typical fluxes ~10-100 kg s-1). Generally, measurements have been made from sources rich in SO2 with high concentrations and fluxes. In this work, for the first time, a UV camera has been used to measure the much lower concentrations and fluxes of SO2 (typical fluxes ~0.01-0.1 kg s-1) in the plumes from moving and stationary ships. Some innovations and trade-offs have been made so that estimates of the fluxes and path concentrations can be retrieved in real-time. Field experiments were conducted at Kongsfjord in Ny Ålesund, Svalbard, where emissions from cruise ships were made, and at the port of Rotterdam, Netherlands, measuring emissions from more than 10 different container and cargo ships. In all cases SO2 path concentrations could be estimated and fluxes determined by measuring ship plume speeds simultaneously using the camera, or by using surface wind speed data from an independent source. Accuracies were compromised in some cases because of the presence of particulates in some ship emissions and the restriction of single-filter UV imagery, a requirement for fast-sampling (>10 Hz) from a single camera. Typical accuracies ranged from 10-30% in path concentration and 10-40% in flux estimation. Despite the ease of use and ability to determine SO2 fluxes from the UV camera system, the limitation in accuracy and precision suggest that the system may only be used under rather ideal circumstances and that currently the technology needs further development to serve as a method to monitor ship emissions for regulatory purposes.

  9. Non-contact imaging of venous compliance in humans using an RGB camera

    NASA Astrophysics Data System (ADS)

    Nakano, Kazuya; Satoh, Ryota; Hoshi, Akira; Matsuda, Ryohei; Suzuki, Hiroyuki; Nishidate, Izumi

    2015-04-01

    We propose a technique for non-contact imaging of venous compliance that uses the red, green, and blue (RGB) camera. Any change in blood concentration is estimated from an RGB image of the skin, and a regression formula is calculated from that change. Venous compliance is obtained from a differential form of the regression formula. In vivo experiments with human subjects confirmed that the proposed method does differentiate the venous compliances among individuals. In addition, the image of venous compliance is obtained by performing the above procedures for each pixel. Thus, we can measure venous compliance without physical contact with sensors and, from the resulting images, observe the spatial distribution of venous compliance, which correlates with the distribution of veins.

  10. High performance gel imaging with a commercial single lens reflex camera

    NASA Astrophysics Data System (ADS)

    Slobodan, J.; Corbett, R.; Wye, N.; Schein, J. E.; Marra, M. A.; Coope, R. J. N.

    2011-03-01

    A high performance gel imaging system was constructed using a digital single lens reflex camera with epi-illumination to image 19 × 23 cm agarose gels with up to 10,000 DNA bands each. It was found to give equivalent performance to a laser scanner in this high throughput DNA fingerprinting application using the fluorophore SYBR Green®. The specificity and sensitivity of the imager and scanner were within 1% using the same band identification software. Low and high cost color filters were also compared and it was found that with care, good results could be obtained with inexpensive dyed acrylic filters in combination with more costly dielectric interference filters, but that very poor combinations were also possible. Methods for determining resolution, dynamic range, and optical efficiency for imagers are also proposed to facilitate comparison between systems.

  11. Design and realization of an image mosaic system on the CCD aerial camera

    NASA Astrophysics Data System (ADS)

    Liu, Hai ying; Wang, Peng; Zhu, Hai bin; Li, Yan; Zhang, Shao jun

    2015-08-01

    It has long been difficulties in aerial photograph to stitch multi-route images into a panoramic image in real time for multi-route flight framing CCD camera with very large amount of data, and high accuracy requirements. An automatic aerial image mosaic system based on GPU development platform is described in this paper. Parallel computing of SIFT feature extraction and matching algorithm module is achieved by using CUDA technology for motion model parameter estimation on the platform, which makes it's possible to stitch multiple CCD images in real-time. Aerial tests proved that the mosaic system meets the user's requirements with 99% accuracy and 30 to 50 times' speed improvement of the normal mosaic system.

  12. WFC3RED: A HST Wide Field Camera 3 Image Processing Pipeline

    NASA Astrophysics Data System (ADS)

    Magee, D. K.; Bouwens, R. J.; Illingworth, G. D.

    2011-07-01

    WFC3RED is a pipeline for automatically processing imaging data taken with the Wide Field Camera 3 instrument on the Hubble Space Telescope (HST). The pipeline currently supports processing of imaging data from both the IR and UVIS channels and is written in Python and C. The automated processing steps include cosmic-ray removal (UVIS), super-sky subtraction, user defined artifact masking, robust alignment and registration for large mosaics, weight map generation, and drizzling onto a final image mosaic. WFC3RED can combined data across different HST observations, visits and proposals without the need for any pre-defined associations. WFC3RED can create imaging products with a signal-to-noise ratio that matches the most careful step-by-step manual WFC3 reductions.

  13. Imaging and radiometric performance simulation for a new high-performance dual-band airborne reconnaissance camera

    NASA Astrophysics Data System (ADS)

    Seong, Sehyun; Yu, Jinhee; Ryu, Dongok; Hong, Jinsuk; Yoon, Jee-Yeon; Kim, Sug-Whan; Lee, Jun-Ho; Shin, Myung-Jin

    2009-05-01

    In recent years, high performance visible and IR cameras have been used widely for tactical airborne reconnaissance. The process improvement for efficient discrimination and analysis of complex target information from active battlefields requires for simultaneous multi-band measurement from airborne platforms at various altitudes. We report a new dual band airborne camera designed for simultaneous registration of both visible and IR imagery from mid-altitude ranges. The camera design uses a common front end optical telescope of around 0.3m in entrance aperture and several relay optical sub-systems capable of delivering both high spatial resolution visible and IR images to the detectors. The camera design is benefited from the use of several optical channels packaged in a compact space and the associated freedom to choose between wide (~3 degrees) and narrow (~1 degree) field of view. In order to investigate both imaging and radiometric performances of the camera, we generated an array of target scenes with optical properties such as reflection, refraction, scattering, transmission and emission. We then combined the target scenes and the camera optical system into the integrated ray tracing simulation environment utilizing Monte Carlo computation technique. Taking realistic atmospheric radiative transfer characteristics into account, both imaging and radiometric performances were then investigated. The simulation results demonstrate successfully that the camera design satisfies NIIRS 7 detection criterion. The camera concept, details of performance simulation computation, the resulting performances are discussed together with future development plan.

  14. Experiences Supporting the Lunar Reconnaissance Orbiter Camera: the Devops Model

    NASA Astrophysics Data System (ADS)

    Licht, A.; Estes, N. M.; Bowman-Cisnesros, E.; Hanger, C. D.

    2013-12-01

    Introduction: The Lunar Reconnaissance Orbiter Camera (LROC) Science Operations Center (SOC) is responsible for instrument targeting, product processing, and archiving [1]. The LROC SOC maintains over 1,000,000 observations with over 300 TB of released data. Processing challenges compound with the acquisition of over 400 Gbits of observations daily creating the need for a robust, efficient, and reliable suite of specialized software. Development Environment: The LROC SOC's software development methodology has evolved over time. Today, the development team operates in close cooperation with the systems administration team in a model known in the IT industry as DevOps. The DevOps model enables a highly productive development environment that facilitates accomplishment of key goals within tight schedules[2]. The LROC SOC DevOps model incorporates industry best practices including prototyping, continuous integration, unit testing, code coverage analysis, version control, and utilizing existing open source software. Scientists and researchers at LROC often prototype algorithms and scripts in a high-level language such as MATLAB or IDL. After the prototype is functionally complete the solution is implemented as production ready software by the developers. Following this process ensures that all controls and requirements set by the LROC SOC DevOps team are met. The LROC SOC also strives to enhance the efficiency of the operations staff by way of weekly presentations and informal mentoring. Many small scripting tasks are assigned to the cognizant operations personnel (end users), allowing for the DevOps team to focus on more complex and mission critical tasks. In addition to leveraging open source software the LROC SOC has also contributed to the open source community by releasing Lunaserv [3]. Findings: The DevOps software model very efficiently provides smooth software releases and maintains team momentum. Scientists prototyping their work has proven to be very efficient

  15. Digital image measurement of specimen deformation based on CCD cameras and Image J software: an application to human pelvic biomechanics

    NASA Astrophysics Data System (ADS)

    Jia, Yongwei; Cheng, Liming; Yu, Guangrong; Lou, Yongjian; Yu, Yan; Chen, Bo; Ding, Zuquan

    2008-03-01

    A method of digital image measurement of specimen deformation based on CCD cameras and Image J software was developed. This method was used to measure the biomechanics behavior of human pelvis. Six cadaveric specimens from the third lumbar vertebra to the proximal 1/3 part of femur were tested. The specimens without any structural abnormalities were dissected of all soft tissue, sparing the hip joint capsules and the ligaments of the pelvic ring and floor. Markers with black dot on white background were affixed to the key regions of the pelvis. Axial loading from the proximal lumbar was applied by MTS in the gradient of 0N to 500N, which simulated the double feet standing stance. The anterior and lateral images of the specimen were obtained through two CCD cameras. Based on Image J software, digital image processing software, which can be freely downloaded from the National Institutes of Health, digital 8-bit images were processed. The procedure includes the recognition of digital marker, image invert, sub-pixel reconstruction, image segmentation, center of mass algorithm based on weighted average of pixel gray values. Vertical displacements of S1 (the first sacral vertebrae) in front view and micro-angular rotation of sacroiliac joint in lateral view were calculated according to the marker movement. The results of digital image measurement showed as following: marker image correlation before and after deformation was excellent. The average correlation coefficient was about 0.983. According to the 768 × 576 pixels image (pixel size 0.68mm × 0.68mm), the precision of the displacement detected in our experiment was about 0.018 pixels and the comparatively error could achieve 1.11\\perthou. The average vertical displacement of S1 of the pelvis was 0.8356+/-0.2830mm under vertical load of 500 Newtons and the average micro-angular rotation of sacroiliac joint in lateral view was 0.584+/-0.221°. The load-displacement curves obtained from our optical measure system

  16. A pnCCD-based, fast direct single electron imaging camera for TEM and STEM

    NASA Astrophysics Data System (ADS)

    Ryll, H.; Simson, M.; Hartmann, R.; Holl, P.; Huth, M.; Ihle, S.; Kondo, Y.; Kotula, P.; Liebel, A.; Müller-Caspary, K.; Rosenauer, A.; Sagawa, R.; Schmidt, J.; Soltau, H.; Strüder, L.

    2016-04-01

    We report on a new camera that is based on a pnCCD sensor for applications in scanning transmission electron microscopy. Emerging new microscopy techniques demand improved detectors with regards to readout rate, sensitivity and radiation hardness, especially in scanning mode. The pnCCD is a 2D imaging sensor that meets these requirements. Its intrinsic radiation hardness permits direct detection of electrons. The pnCCD is read out at a rate of 1,150 frames per second with an image area of 264 x 264 pixel. In binning or windowing modes, the readout rate is increased almost linearly, for example to 4000 frames per second at 4× binning (264 x 66 pixel). Single electrons with energies from 300 keV down to 5 keV can be distinguished due to the high sensitivity of the detector. Three applications in scanning transmission electron microscopy are highlighted to demonstrate that the pnCCD satisfies experimental requirements, especially fast recording of 2D images. In the first application, 65536 2D diffraction patterns were recorded in 70 s. STEM images corresponding to intensities of various diffraction peaks were reconstructed. For the second application, the microscope was operated in a Lorentz-like mode. Magnetic domains were imaged in an area of 256 x 256 sample points in less than 37 seconds for a total of 65536 images each with 264 x 132 pixels. Due to information provided by the two-dimensional images, not only the amplitude but also the direction of the magnetic field could be determined. In the third application, millisecond images of a semiconductor nanostructure were recorded to determine the lattice strain in the sample. A speed-up in measurement time by a factor of 200 could be achieved compared to a previously used camera system.

  17. A Method to Solve Interior and Exterior Camera Calibration Parameters for Image Resection

    NASA Technical Reports Server (NTRS)

    Samtaney, Ravi

    1999-01-01

    An iterative method is presented to solve the internal and external camera calibration parameters, given model target points and their images from one or more camera locations. The direct linear transform formulation was used to obtain a guess for the iterative method, and herein lies one of the strengths of the present method. In all test cases, the method converged to the correct solution. In general, an overdetermined system of nonlinear equations is solved in the least-squares sense. The iterative method presented is based on Newton-Raphson for solving systems of nonlinear algebraic equations. The Jacobian is analytically derived and the pseudo-inverse of the Jacobian is obtained by singular value decomposition.

  18. Background and imaging simulations for the hard X-ray camera of the MIRAX mission

    NASA Astrophysics Data System (ADS)

    Castro, M.; Braga, J.; Penacchioni, A.; D'Amico, F.; Sacahui, R.

    2016-07-01

    We report the results of detailed Monte Carlo simulations of the performance expected both at balloon altitudes and at the probable satellite orbit of a hard X-ray coded-aperture camera being developed for the Monitor e Imageador de RAios X (MIRAX) mission. Based on a thorough mass model of the instrument and detailed specifications of the spectra and angular dependence of the various relevant radiation fields at both the stratospheric and orbital environments, we have used the well-known package GEANT4 to simulate the instrumental background of the camera. We also show simulated images of source fields to be observed and calculated the detailed sensitivity of the instrument in both situations. The results reported here are especially important to researchers in this field considering that we provide important information, not easily found in the literature, on how to prepare input files and calculate crucial instrumental parameters to perform GEANT4 simulations for high-energy astrophysics space experiments.

  19. Conceptual design of a camera system for neutron imaging in low fusion power tokamaks

    NASA Astrophysics Data System (ADS)

    Xie, X.; Yuan, X.; Zhang, X.; Nocente, M.; Chen, Z.; Peng, X.; Cui, Z.; Du, T.; Hu, Z.; Li, T.; Fan, T.; Chen, J.; Li, X.; Zhang, G.; Yuan, G.; Yang, J.; Yang, Q.

    2016-02-01

    The basic principles for designing a camera system for neutron imaging in low fusion power tokamaks are illustrated for the case of the HL-2A tokamak device. HL-2A has an approximately circular cross section, with total neutron yields of about 1012 n/s under 1 MW neutral beam injection (NBI) heating. The accuracy in determining the width of the neutron emission profile and the plasma vertical position are chosen as relevant parameters for design optimization. Typical neutron emission profiles and neutron energy spectra are calculated by Monte Carlo method. A reference design is assumed, for which the direct and scattered neutron fluences are assessed and the neutron count profile of the neutron camera is obtained. Three other designs are presented for comparison. The reference design is found to have the best performance for assessing the width of peaked to broadened neutron emission profiles. It also performs well for the assessment of the vertical position.

  20. A new sensor alignment method for an 8k x 4k-pixel ultrahigh definition camera with four imagers

    NASA Astrophysics Data System (ADS)

    Yamashita, Takayuki; Mitani, Kohji; Shimamoto, Hiroshi; Shirakawa, Miho; Okano, Fumio

    2004-06-01

    We describe a precise alignment method of attaching imagers to a prism to produce an ultra-high definition color camera system. We have already developed a prototype camera with 4-k scanning lines using this alignment method. To increase its spatial resolution, this camera has four 8-megapixel imagers (GGBR), which are attached to a prism with a half-pixel pitch offset so that their pixel arrangement is equivalent to that of a single-chip color-imaging sensor with a Bayer-pattern color filter. The precision of their positioning influences the resolution of the reproduced images. The small pixels in the latest imager make it more difficult to maintain precise imager positions. A precise alignment method for attaching imagers to prism is therefore essential for developing a camera system with high resolution. We propose a method with high detectivity using a sinusoidal pattern chart that easily reproduced by one imager, and a signal process. Images from this camera can attain a limiting resolution of more than 3200 TV lines.

  1. Megapixel imaging camera for expanded H{sup {minus}} beam measurements

    SciTech Connect

    Simmons, J.E.; Lillberg, J.W.; McKee, R.J.; Slice, R.W.; Torrez, J.H.; McCurnin, T.W.; Sanchez, P.G.

    1994-02-01

    A charge coupled device (CCD) imaging camera system has been developed as part of the Ground Test Accelerator project at the Los Alamos National Laboratory to measure the properties of a large diameter, neutral particle beam. The camera is designed to operate in the accelerator vacuum system for extended periods of time. It would normally be cooled to reduce dark current. The CCD contains 1024 {times} 1024 pixels with pixel size of 19 {times} 19 {mu}m{sup 2} and with four phase parallel clocking and two phase serial clocking. The serial clock rate is 2.5{times}10{sup 5} pixels per second. Clock sequence and timing are controlled by an external logic-word generator. The DC bias voltages are likewise located externally. The camera contains circuitry to generate the analog clocks for the CCD and also contains the output video signal amplifier. Reset switching noise is removed by an external signal processor that employs delay elements to provide noise suppression by the method of double-correlated sampling. The video signal is digitized to 12 bits in an analog to digital converter (ADC) module controlled by a central processor module. Both modules are located in a VME-type computer crate that communicates via ethernet with a separate workstation where overall control is exercised and image processing occurs. Under cooled conditions the camera shows good linearity with dynamic range of 2000 and with dark noise fluctuations of about {plus_minus}1/2 ADC count. Full well capacity is about 5{times}10{sup 5} electron charges.

  2. Full 3-D cluster-based iterative image reconstruction tool for a small animal PET camera

    NASA Astrophysics Data System (ADS)

    Valastyán, I.; Imrek, J.; Molnár, J.; Novák, D.; Balkay, L.; Emri, M.; Trón, L.; Bükki, T.; Kerek, A.

    2007-02-01

    Iterative reconstruction methods are commonly used to obtain images with high resolution and good signal-to-noise ratio in nuclear imaging. The aim of this work was to develop a scalable, fast, cluster based, fully 3-D iterative image reconstruction package for our small animal PET camera, the miniPET. The reconstruction package is developed to determine the 3-D radioactivity distribution from list mode type of data sets and it can also simulate noise-free projections of digital phantoms. We separated the system matrix generation and the fully 3-D iterative reconstruction process. As the detector geometry is fixed for a given camera, the system matrix describing this geometry is calculated only once and used for every image reconstruction, making the process much faster. The Poisson and the random noise sensitivity of the ML-EM iterative algorithm were studied for our small animal PET system with the help of the simulation and reconstruction tool. The reconstruction tool has also been tested with data collected by the miniPET from a line and a cylinder shaped phantom and also a rat.

  3. Loop closure detection by algorithmic information theory: implemented on range and camera image data.

    PubMed

    Ravari, Alireza Norouzzadeh; Taghirad, Hamid D

    2014-10-01

    In this paper the problem of loop closing from depth or camera image information in an unknown environment is investigated. A sparse model is constructed from a parametric dictionary for every range or camera image as mobile robot observations. In contrast to high-dimensional feature-based representations, in this model, the dimension of the sensor measurements' representations is reduced. Considering the loop closure detection as a clustering problem in high-dimensional space, little attention has been paid to the curse of dimensionality in the existing state-of-the-art algorithms. In this paper, a representation is developed from a sparse model of images, with a lower dimension than original sensor observations. Exploiting the algorithmic information theory, the representation is developed such that it has the geometrically transformation invariant property in the sense of Kolmogorov complexity. A universal normalized metric is used for comparison of complexity based representations of image models. Finally, a distinctive property of normalized compression distance is exploited for detecting similar places and rejecting incorrect loop closure candidates. Experimental results show efficiency and accuracy of the proposed method in comparison to the state-of-the-art algorithms and some recently proposed methods. PMID:24968363

  4. Tomographic Small-Animal Imaging Using a High-Resolution Semiconductor Camera

    PubMed Central

    Kastis, GA; Wu, MC; Balzer, SJ; Wilson, DW; Furenlid, LR; Stevenson, G; Barber, HB; Barrett, HH; Woolfenden, JM; Kelly, P; Appleby, M

    2015-01-01

    We have developed a high-resolution, compact semiconductor camera for nuclear medicine applications. The modular unit has been used to obtain tomographic images of phantoms and mice. The system consists of a 64 x 64 CdZnTe detector array and a parallel-hole tungsten collimator mounted inside a 17 cm x 5.3 cm x 3.7 cm tungsten-aluminum housing. The detector is a 2.5 cm x 2.5 cm x 0.15 cm slab of CdZnTe connected to a 64 x 64 multiplexer readout via indium-bump bonding. The collimator is 7 mm thick, with a 0.38 mm pitch that matches the detector pixel pitch. We obtained a series of projections by rotating the object in front of the camera. The axis of rotation was vertical and about 1.5 cm away from the collimator face. Mouse holders were made out of acrylic plastic tubing to facilitate rotation and the administration of gas anesthetic. Acquisition times were varied from 60 sec to 90 sec per image for a total of 60 projections at an equal spacing of 6 degrees between projections. We present tomographic images of a line phantom and mouse bone scan and assess the properties of the system. The reconstructed images demonstrate spatial resolution on the order of 1–2 mm. PMID:26568676

  5. Real-Time On-Board Processing Validation of MSPI Ground Camera Images

    NASA Technical Reports Server (NTRS)

    Pingree, Paula J.; Werne, Thomas A.; Bekker, Dmitriy L.

    2010-01-01

    The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA's Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA including PowerPC440 processors we have implemented a least squares fitting algorithm that extracts intensity and polarimetric parameters in real-time, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information.

  6. Superresolution imaging system on innovative localization microscopy technique with commonly using dyes and CMOS camera

    NASA Astrophysics Data System (ADS)

    Dudenkova, V.; Zakharov, Yu.

    2015-05-01

    Optical methods for study biological tissue and cell at micro- and nanoscale level step now over diffraction limit. Really it is single molecule localization techniques that achieve the highest spatial resolution. One of those techniques, called bleaching/blinking assisted localization microscopy (BaLM) relies on the intrinsic bleaching and blinking behavior characteristic of commonly used fluorescent probes. This feature is the base of BaLM image series acquisition and data analysis. In our work blinking of single fluorescent spot against a background of others comes to light by subtraction of time series successive frames. Then digital estimation gives the center of the spot as a point of fluorescent molecule presence, which transfers to other image with higher resolution according to accuracy of the center localization. It is a part of image with improved resolution. This approach allows overlapping fluorophores and not requires single photon sensitivity, so we use 8,8 megapixel CMOS camera with smallest (1.55 um) pixel size. This instrumentation on the base of Zeiss Axioscope 2 FS MOT allows image transmission from object plane to matrix on a scale less than 100 nm/pixel using 20x-objective, thereafter the same resolution and 5 times more field of view as compared to EMCCD camera with 6 um pixel size. To optimize excitation light power, frame rate and gain of camera we have made appropriate estimations taking into account fluorophores behaviors features and equipment characteristics. Finely we have clearly distinguishable details of the sample in the processed field of view.

  7. An evaluation of a fluorescent screen-isocon camera system for x-ray imaging in radiology.

    PubMed

    Nelson, R S; Barbaric, Z L; Gomes, A S; Moler, C L; Deckard, M E

    1982-01-01

    A large field format imaging system which utilizes a flat fluorescent screen rather than the traditional image intensifier as the primary x-ray detector is discussed in this paper. A low light level image isocon camera is optically coupled to a rare-earth screen. An overview of the isocon camera and its return beam mode of operation is included. Theoretical limitations to this approach to real time radiographic imaging are discussed in terms of system efficiency and signal-to-noise ratio (SNR) requirements. The viability of this concept for radiographic imaging is considered with respect to the image intensifier-camera unit. The merits of employing a CsI:Na screen as the primary detector and an isocon tube with an improved SNR are presented as potential areas for further investigation. PMID:7155082

  8. Temperature dependent operation of PSAPD-based compact gamma camera for SPECT imaging.

    PubMed

    Kim, Sangtaek; McClish, Mickel; Alhassen, Fares; Seo, Youngho; Shah, Kanai S; Gould, Robert G

    2011-10-10

    We investigated the dependence of image quality on the temperature of a position sensitive avalanche photodiode (PSAPD)-based small animal single photon emission computed tomography (SPECT) gamma camera with a CsI:Tl scintillator. Currently, nitrogen gas cooling is preferred to operate PSAPDs in order to minimize the dark current shot noise. Being able to operate a PSAPD at a relatively high temperature (e.g., 5 °C) would allow a more compact and simple cooling system for the PSAPD. In our investigation, the temperature of the PSAPD was controlled by varying the flow of cold nitrogen gas through the PSAPD module and varied from -40 °C to 20 °C. Three experiments were performed to demonstrate the performance variation over this temperature range. The point spread function (PSF) of the gamma camera was measured at various temperatures, showing variation of full-width-half-maximum (FWHM) of the PSF. In addition, a (99m)Tc-pertechnetate (140 keV) flood source was imaged and the visibility of the scintillator segmentation (16×16 array, 8 mm × 8 mm area, 400 μm pixel size) at different temperatures was evaluated. Comparison of image quality was made at -25 °C and 5 °C using a mouse heart phantom filled with an aqueous solution of (99m)Tc-pertechnetate and imaged using a 0.5 mm pinhole collimator made of tungsten. The reconstructed image quality of the mouse heart phantom at 5 °C degraded in comparision to the reconstructed image quality at -25 °C. However, the defect and structure of the mouse heart phantom were clearly observed, showing the feasibility of operating PSAPDs for SPECT imaging at 5 °C, a temperature that would not need the nitrogen cooling. All PSAPD evaluations were conducted with an applied bias voltage that allowed the highest gain at a given temperature. PMID:24465051

  9. Temperature dependent operation of PSAPD-based compact gamma camera for SPECT imaging

    PubMed Central

    Kim, Sangtaek; McClish, Mickel; Alhassen, Fares; Seo, Youngho; Shah, Kanai S.; Gould, Robert G.

    2011-01-01

    We investigated the dependence of image quality on the temperature of a position sensitive avalanche photodiode (PSAPD)-based small animal single photon emission computed tomography (SPECT) gamma camera with a CsI:Tl scintillator. Currently, nitrogen gas cooling is preferred to operate PSAPDs in order to minimize the dark current shot noise. Being able to operate a PSAPD at a relatively high temperature (e.g., 5 °C) would allow a more compact and simple cooling system for the PSAPD. In our investigation, the temperature of the PSAPD was controlled by varying the flow of cold nitrogen gas through the PSAPD module and varied from −40 °C to 20 °C. Three experiments were performed to demonstrate the performance variation over this temperature range. The point spread function (PSF) of the gamma camera was measured at various temperatures, showing variation of full-width-half-maximum (FWHM) of the PSF. In addition, a 99mTc-pertechnetate (140 keV) flood source was imaged and the visibility of the scintillator segmentation (16×16 array, 8 mm × 8 mm area, 400 μm pixel size) at different temperatures was evaluated. Comparison of image quality was made at −25 °C and 5 °C using a mouse heart phantom filled with an aqueous solution of 99mTc-pertechnetate and imaged using a 0.5 mm pinhole collimator made of tungsten. The reconstructed image quality of the mouse heart phantom at 5 °C degraded in comparision to the reconstructed image quality at −25 °C. However, the defect and structure of the mouse heart phantom were clearly observed, showing the feasibility of operating PSAPDs for SPECT imaging at 5 °C, a temperature that would not need the nitrogen cooling. All PSAPD evaluations were conducted with an applied bias voltage that allowed the highest gain at a given temperature. PMID:24465051

  10. Development of proton CT imaging system using plastic scintillator and CCD camera.

    PubMed

    Tanaka, Sodai; Nishio, Teiji; Matsushita, Keiichiro; Tsuneda, Masato; Kabuki, Shigeto; Uesaka, Mitsuru

    2016-06-01

    A proton computed tomography (pCT) imaging system was constructed for evaluation of the error of an x-ray CT (xCT)-to-WEL (water-equivalent length) conversion in treatment planning for proton therapy. In this system, the scintillation light integrated along the beam direction is obtained by photography using the CCD camera, which enables fast and easy data acquisition. The light intensity is converted to the range of the proton beam using a light-to-range conversion table made beforehand, and a pCT image is reconstructed. An experiment for demonstration of the pCT system was performed using a 70 MeV proton beam provided by the AVF930 cyclotron at the National Institute of Radiological Sciences. Three-dimensional pCT images were reconstructed from the experimental data. A thin structure of approximately 1 mm was clearly observed, with spatial resolution of pCT images at the same level as that of xCT images. The pCT images of various substances were reconstructed to evaluate the pixel value of pCT images. The image quality was investigated with regard to deterioration including multiple Coulomb scattering. PMID:27191962

  11. The Large Binocular Camera image simulator: predicting the performances of LBC

    NASA Astrophysics Data System (ADS)

    Grazian, Andrea; Fontana, Adriano; De Santis, Cristian; Gallozzi, Stefano; Giallongo, Emanuele

    2004-09-01

    The LBC (Large Binocular Camera) Image Simulator is a package for generating artificial images in the typical FITS format. It operates on real or artificial images, simulating the expected performances of real instruments including several observing conditions (filters, air-mass, flat-field, exposure time) and creating images with the LBC instrumental artifacts (optical deformations, noise, CCD architectures). This simulator can be used also to produce artificial images for other existing and future telescopes, since it is very flexible on its structure. The main aim of LBCSIM is to support the development of pipeline and data analysis procedure able to cope with wide field imaging and fast reduction of huge amount of photometric data. The software consists of three stand alone programs written in C language, using IRAF and running under Linux OS. The LBC Image Simulator is built with particular attention to the Virtual Observatory and Data Grid applications. In this paper, we first describe the software, the performances and several tests carried out before the public release and some examples for the users. In particular, we compared the Hubble Deep Field South (HDFS) as seen by FORS1 with a simulated image and found that the agreement is good. Then, we use this software to predict the expected performances of the LBC instrument by means of realistic simulations of deep field observations with the LBT telescope.

  12. Development of proton CT imaging system using plastic scintillator and CCD camera

    NASA Astrophysics Data System (ADS)

    Tanaka, Sodai; Nishio, Teiji; Matsushita, Keiichiro; Tsuneda, Masato; Kabuki, Shigeto; Uesaka, Mitsuru

    2016-06-01

    A proton computed tomography (pCT) imaging system was constructed for evaluation of the error of an x-ray CT (xCT)-to-WEL (water-equivalent length) conversion in treatment planning for proton therapy. In this system, the scintillation light integrated along the beam direction is obtained by photography using the CCD camera, which enables fast and easy data acquisition. The light intensity is converted to the range of the proton beam using a light-to-range conversion table made beforehand, and a pCT image is reconstructed. An experiment for demonstration of the pCT system was performed using a 70 MeV proton beam provided by the AVF930 cyclotron at the National Institute of Radiological Sciences. Three-dimensional pCT images were reconstructed from the experimental data. A thin structure of approximately 1 mm was clearly observed, with spatial resolution of pCT images at the same level as that of xCT images. The pCT images of various substances were reconstructed to evaluate the pixel value of pCT images. The image quality was investigated with regard to deterioration including multiple Coulomb scattering.

  13. Estimate of DTM Degradation due to Image Compression for the Stereo Camera of the Bepicolombo Mission

    NASA Astrophysics Data System (ADS)

    Re, C.; Simioni, E.; Cremonese, G.; Roncella, R.; Forlani, G.; Langevin, Y.; Da Deppo, V.; Naletto, G.; Salemi, G.

    2016-06-01

    The great amount of data that will be produced during the imaging of Mercury by the stereo camera (STC) of the BepiColombo mission needs a compromise with the restrictions imposed by the band downlink that could drastically reduce the duration and frequency of the observations. The implementation of an on-board real time data compression strategy preserving as much information as possible is therefore mandatory. The degradation that image compression might cause to the DTM accuracy is worth to be investigated. During the stereo-validation procedure of the innovative STC imaging system, several image pairs of an anorthosite sample and a modelled piece of concrete have been acquired under different illumination angles. This set of images has been used to test the effects of the compression algorithm (Langevin and Forni, 2000) on the accuracy of the DTM produced by dense image matching. Different configurations taking in account at the same time both the illumination of the surface and the compression ratio, have been considered. The accuracy of the DTMs is evaluated by comparison with a high resolution laser-scan acquisition of the same targets. The error assessment included also an analysis on the image plane indicating the influence of the compression procedure on the image measurements.

  14. Airborne imaging for heritage documentation using the Fotokite tethered flying camera

    NASA Astrophysics Data System (ADS)

    Verhoeven, Geert; Lupashin, Sergei; Briese, Christian; Doneus, Michael

    2014-05-01

    Since the beginning of aerial photography, researchers used all kinds of devices (from pigeons, kites, poles, and balloons to rockets) to take still cameras aloft and remotely gather aerial imagery. To date, many of these unmanned devices are still used for what has been referred to as Low-Altitude Aerial Photography or LAAP. In addition to these more traditional camera platforms, radio-controlled (multi-)copter platforms have recently added a new aspect to LAAP. Although model airplanes have been around for several decades, the decreasing cost, increasing functionality and stability of ready-to-fly multi-copter systems has proliferated their use among non-hobbyists. As such, they became a very popular tool for aerial imaging. The overwhelming amount of currently available brands and types (heli-, dual-, tri-, quad-, hexa-, octo-, dodeca-, deca-hexa and deca-octocopters), together with the wide variety of navigation options (e.g. altitude and position hold, waypoint flight) and camera mounts indicate that these platforms are here to stay for some time. Given the multitude of still camera types and the image quality they are currently capable of, endless combinations of low- and high-cost LAAP solutions are available. In addition, LAAP allows for the exploitation of new imaging techniques, as it is often only a matter of lifting the appropriate device (e.g. video cameras, thermal frame imagers, hyperspectral line sensors). Archaeologists were among the first to adopt this technology, as it provided them with a means to easily acquire essential data from a unique point of view, whether for simple illustration purposes of standing historic structures or to compute three-dimensional (3D) models and orthophotographs from excavation areas. However, even very cheap multi-copters models require certain skills to pilot them safely. Additionally, malfunction or overconfidence might lift these devices to altitudes where they can interfere with manned aircrafts. As such, the

  15. Design of a smartphone-camera-based fluorescence imaging system for the detection of oral cancer

    NASA Astrophysics Data System (ADS)

    Uthoff, Ross

    Shown is the design of the Smartphone Oral Cancer Detection System (SOCeeDS). The SOCeeDS attaches to a smartphone and utilizes its embedded imaging optics and sensors to capture images of the oral cavity to detect oral cancer. Violet illumination sources excite the oral tissues to induce fluorescence. Images are captured with the smartphone's onboard camera. Areas where the tissues of the oral cavity are darkened signify an absence of fluorescence signal, indicating breakdown in tissue structure brought by precancerous or cancerous conditions. With this data the patient can seek further testing and diagnosis as needed. Proliferation of this device will allow communities with limited access to healthcare professionals a tool to detect cancer in its early stages, increasing the likelihood of cancer reversal.

  16. First experience DaTSCAN imaging using cadmium-zinc-telluride gamma camera SPECT.

    PubMed

    Farid, Karim; Queneau, Mathieu; Guernou, Mohamed; Lussato, David; Poullias, Xavier; Petras, Slavomir; Caillat-Vigneron, Nadine; Songy, Bernard

    2012-08-01

    We report our first experience of brain DaTSCAN SPECT imaging using cadmium-zinc-telluride gamma camera (CZT-GC) in 2 cases: a 64-year-old patient suffering from essential tremor and a 73-year-old patient presenting with atypical bilateral extrapyramidal syndrome. In both cases, 2 different acquisitions were performed and compared, using a double-head Anger-GC, followed immediately by a second acquisition on CZT-GC. There were no significant visual differences between images generated by different GC. Our first result suggests that DaTSCAN SPECT is feasible on CZT-GC, allowing both injected dose and acquisition time reductions without compromising image quality. This experience needs to be evaluated in larger series. PMID:22785531

  17. Toward Real-time quantum imaging with a single pixel camera

    SciTech Connect

    Lawrie, Benjamin J; Pooser, Raphael C

    2013-01-01

    We present a workbench for the study of real-time quantum imaging by measuring the frame-by-frame quantum noise reduction of multi-spatial-mode twin beams generated by four wave mixing in Rb vapor. Exploiting the multiple spatial modes of this squeezed light source, we utilize spatial light modulators to selectively transmit macropixels of quantum correlated modes from each of the twin beams to a high quantum efficiency balanced detector. In low-light-level imaging applications, the ability to measure the quantum correlations between individual spatial modes and macropixels of spatial modes with a single pixel camera will facilitate compressive quantum imaging with sensitivity below the photon shot noise limit.

  18. Gamma camera imaging for studying intestinal absorption and whole-body distribution of selenomethionine.

    PubMed

    Madsen, Jan L; Sjögreen-Gleisner, Katarina; Elema, Dennis R; Søndergaard, Lasse R; Rasmussen, Palle; Fuglsang, Stefan; Ljungberg, Michael; Damgaard, Morten

    2014-02-01

    Se metabolism in humans is not well characterised. Currently, the estimates of Se absorption, whole-body retention and excretion are being obtained from balance and tracer studies. In the present study, we used gamma camera imaging to evaluate the whole-body retention and distribution of radiolabelled selenomethionine (SeMet), the predominant form of Se present in foods. A total of eight healthy young men participated in the study. After consumption of a meal containing 4 MBq [⁷⁵Se]L-SeMet ([⁷⁵Se]SeMet), whole-body gamma camera scanning was performed for 45 min every hour over a 6 h period, every second hour for the next 18 h and once on each of the subsequent 6 d. Blood, urine and faecal samples were collected to determine the plasma content of [⁷⁵Se]SeMet as well as its excretion in urine and faeces. Imaging showed that 87·9 (sd 3·3)% of the administered activity of [⁷⁵Se]SeMet was retained within the body after 7 d. In contrast, the measured excretion in urine and faeces for the 7 d period was 8·2 (sd 1·1)% of the activity. Time-activity curves were generated for the whole body, stomach, liver, abdomen (other than the stomach and the liver), brain and femoral muscles. Gamma camera imaging allows for the assessment of the postprandial absorption of SeMet. This technique may also permit concurrent studies of organ turnover of SeMet. PMID:23930999

  19. ELOp EO/IR LOROP camera: image stabilization for dual-band whiskbroom scanning photography

    NASA Astrophysics Data System (ADS)

    Petrushevsky, Vladimir; Karklinsky, Yehoshua; Chernobrov, Arie

    2003-01-01

    The ELOP dual band LOROP camera was designed as a payload of a 300 gal reconnaissance pod capable of being carried by a single-engineerd fighter aircrat like F-16. The optical arrangement provides coincidence of the IR and EO optical axes, as well as equality of the fields-of-view. These features allow the same sacn coverage to be achieved, and the same gimbals control software to be used for the visible-light-only, IR-only and simultaneous dual band photography. Because of intensive, broadband vibration existing in teh pod environment, special attention was given to image stabilization system. Nevertheless, residual vibraiton still exists in a wide frequency range spreading from zero frequency to the detector integration rate and beyond it. Hence, evaluation of the camera performance could not rely on the well-known analytical solutions for MTFMOTION. The image motion is deinfed in terms of the Power Spectral Density throughout the whole frequency range of interest. The expected MTFMOTION is calculated numerically using a statistical approach. Aspects of the staggered-structure IR detecotr application in oblique photography are discussed. Particuarly, the ground footprint of the IR detector is much wider along-scan than one of the EO detector, requiring considerations to be implemented in order to prevent IR image deformation.

  20. Precise Trajectory Reconstruction of CE-3 Hovering Stage By Landing Camera Images

    NASA Astrophysics Data System (ADS)

    Yan, W.; Liu, J.; Li, C.; Ren, X.; Mu, L.; Gao, X.; Zeng, X.

    2014-12-01

    Chang'E-3 (CE-3) is part of the second phase of the Chinese Lunar Exploration Program, incorporating a lander and China's first lunar rover. It was landed on 14 December, 2013 successfully. Hovering and obstacle avoidance stages are essential for CE-3 safety soft landing so that precise spacecraft trajectory in these stages are of great significance to verify orbital control strategy, to optimize orbital design, to accurately determine the landing site of CE-3, and to analyze the geological background of the landing site. Because the time consumption of these stages is just 25s, it is difficult to present spacecraft's subtle movement by Measurement and Control System or by radio observations. Under this background, the trajectory reconstruction based on landing camera images can be used to obtain the trajectory of CE-3 because of its technical advantages such as unaffecting by lunar gravity field spacecraft kinetic model, high resolution, high frame rate, and so on. In this paper, the trajectory of CE-3 before and after entering hovering stage was reconstructed by landing camera images from frame 3092 to frame 3180, which lasted about 9s, under Single Image Space Resection (SISR). The results show that CE-3's subtle changes during hovering stage can be emerged by the reconstructed trajectory. The horizontal accuracy of spacecraft position was up to 1.4m while vertical accuracy was up to 0.76m. The results can be used for orbital control strategy analysis and some other application fields.

  1. The development of a subsea holographic camera for the imaging and analysis of marine organisms

    NASA Astrophysics Data System (ADS)

    Watson, John

    2004-06-01

    In this overview of the entire HoloMar system, we describe the design, development and field deployment of the fully-functioning, prototype, underwater holographic camera (HoloCam) followed by the dedicated replay facility (HoloScan) and the associated image processing and extraction of data from the holograms. The HoloCam consists of a laser and power supply, holographic recording optics and holographic plate holders, a water-tight housing and a support frame. It incorporates two basic holographic geometries, in-line and off-axis such that a wide range of species, sizes and concentrations can be recorded. After holograms have been recorded and processed thay are reconstructed in full three-dimensional detail in air in a dedicated replay facility. A computer controlled microscope, using video cameras to record the image at a given depth, is used to digitize the scene. Specially developed software extracts a binarized image of an object in its true focal plane and is classified using a neural network. The HoloCam was deployed on separate cruises in a Scottish sea loch (Loch Etive) to a depth of 100 m and over 300 holograms recorded.

  2. Static laser speckle contrast analysis for noninvasive burn diagnosis using a camera-phone imager.

    PubMed

    Ragol, Sigal; Remer, Itay; Shoham, Yaron; Hazan, Sivan; Willenz, Udi; Sinelnikov, Igor; Dronov, Vladimir; Rosenberg, Lior; Bilenca, Alberto

    2015-08-01

    Laser speckle contrast analysis (LASCA) is an established optical technique for accurate widefield visualization of relative blood perfusion when no or minimal scattering from static tissue elements is present, as demonstrated, for example, in LASCA imaging of the exposed cortex. However, when LASCA is applied to diagnosis of burn wounds, light is backscattered from both moving blood and static burn scatterers, and thus the spatial speckle contrast includes both perfusion and nonperfusion components and cannot be straightforwardly associated to blood flow. We extract from speckle contrast images of burn wounds the nonperfusion (static) component and discover that it conveys useful information on the ratio of static-to-dynamic scattering composition of the wound, enabling identification of burns of different depth in a porcine model in vivo within the first 48 h postburn. Our findings suggest that relative changes in the static-to-dynamic scattering composition of burns can dominate relative changes in blood flow for burns of different severity. Unlike conventional LASCA systems that employ scientific or industrial-grade cameras, our LASCA system is realized here using a camera phone, showing the potential to enable LASCA-based burn diagnosis with a simple imager. PMID:26271055

  3. Intensified array camera imaging of solid surface combustion aboard the NASA Learjet

    NASA Technical Reports Server (NTRS)

    Weiland, Karen J.

    1992-01-01

    An intensified array camera was used to image weakly luminous flames spreading over thermally thin paper samples in a low gravity environment aboard the NASA-Lewis Learjet. The aircraft offers 10 to 20 sec of reduced gravity during execution of a Keplerian trajectory and allows the use of instrumentation that is delicate or requires higher electrical power than is available in drop towers. The intensified array camera is a charge intensified device type that responds to light between 400 and 900 nm and has a minimum sensitivity of 10(exp 6) footcandles. The paper sample, either ashless filter paper or a lab wiper, burns inside a sealed chamber which is filled with 21, 18, or 15 pct. oxygen in nitrogen at one atmosphere. The camera views the edge of the paper and its output is recorded on videotape. Flame positions are measured every 0.1 sec to calculate flame spread rates. Comparisons with drop tower data indicate that the flame shapes and spread rates are affected by the residual g level in the aircraft.

  4. Synchroscan streak camera imaging at a 15-MeV photoinjector with emittance exchange

    NASA Astrophysics Data System (ADS)

    Lumpkin, A. H.; Ruan, J.; Thurman-Keup, R.

    2012-09-01

    At the Fermilab A0 photoinjector facility, bunch-length measurements of the laser micropulse and the e-beam micropulse have been done in the past with a fast single-sweep module of the Hamamatsu C5680 streak camera with an intrinsic shot-to-shot trigger jitter of 10-20 ps. We have upgraded the camera system with the synchroscan module tuned to 81.25 MHz to provide synchronous summing capability with less than 1.5 ps FWHM trigger jitter and a phase-locked delay box to provide phase stability of ˜1 ps over 10 s of minutes. These steps allowed us to measure both the UV laser pulse train at 263 nm and the e-beam via optical transition radiation (OTR). Due to the low electron beam energies and OTR signals, we typically summed over 50 micropulses with 0.25-1 nC per micropulse. The phase-locked delay box allowed us to assess chromatic temporal effects and instigated another upgrade to an all-mirror input optics barrel. In addition, we added a slow sweep horizontal deflection plug-in unit to provide dual-sweep capability for the streak camera. We report on a series of measurements made during the commissioning of these upgrades including bunch-length and phase effects using the emittance exchange beamline and simultaneous imaging of a UV drive laser component, OTR, and the 800 nm diagnostics laser.

  5. The Effect of Light Conditions on Photoplethysmographic Image Acquisition Using a Commercial Camera

    PubMed Central

    Liu, He; Wang, Yadong

    2014-01-01

    Cameras embedded in consumer devices have previously been used as physiological information sensors. The waveform of the photoplethysmographic image (PPGi) signals may be significantly affected by the light spectra and intensity. The purpose of this paper is to evaluate the performance of PPGi waveform acquisition in the red, green, and blue channels using a commercial camera in different light conditions. The system, developed for this paper, comprises of a commercial camera and light sources with varied spectra and intensities. Signals were acquired from the fingertips of 12 healthy subjects. Extensive experiments, using different wavelength lights and white light with variation light intensities, respectively, reported in this paper, showed that almost all light spectra can acquire acceptable pulse rates, but only 470-, 490-, 505-, 590-, 600-, 610-, 625-, and 660-nm wavelength lights showed better performance in PPGi waveform compared with gold standard. With lower light intensity, the light spectra >600 nm still showed better performance. The change in pulse amplitude (ac) and dc amplitude was also investigated with the different light intensity and light spectra. With increasing light intensity, the dc amplitude increased, whereas ac component showed an initial increase followed by a decrease. Most of the subjects achieved their maximum averaging ac output when averaging dc output was in the range from 180 to 220 pixel values (8 b, 255 maximum pixel value). The results suggested that an adaptive solution could be developed to optimize the design of PPGi-based physiological signal acquisition devices in different light conditions. PMID:27170870

  6. Physical Activity Recognition Based on Motion in Images Acquired by a Wearable Camera

    PubMed Central

    Zhang, Hong; Li, Lu; Jia, Wenyan; Fernstrom, John D.; Sclabassi, Robert J.; Mao, Zhi-Hong; Sun, Mingui

    2011-01-01

    A new technique to extract and evaluate physical activity patterns from image sequences captured by a wearable camera is presented in this paper. Unlike standard activity recognition schemes, the video data captured by our device do not include the wearer him/herself. The physical activity of the wearer, such as walking or exercising, is analyzed indirectly through the camera motion extracted from the acquired video frames. Two key tasks, pixel correspondence identification and motion feature extraction, are studied to recognize activity patterns. We utilize a multiscale approach to identify pixel correspondences. When compared with the existing methods such as the Good Features detector and the Speed-up Robust Feature (SURF) detector, our technique is more accurate and computationally efficient. Once the pixel correspondences are determined which define representative motion vectors, we build a set of activity pattern features based on motion statistics in each frame. Finally, the physical activity of the person wearing a camera is determined according to the global motion distribution in the video. Our algorithms are tested using different machine learning techniques such as the K-Nearest Neighbor (KNN), Naive Bayesian and Support Vector Machine (SVM). The results show that many types of physical activities can be recognized from field acquired real-world video. Our results also indicate that, with a design of specific motion features in the input vectors, different classifiers can be used successfully with similar performances. PMID:21779142

  7. Camera Image Transformation and Registration for Safe Spacecraft Landing and Hazard Avoidance

    NASA Technical Reports Server (NTRS)

    Jones, Brandon M.

    2005-01-01

    Inherent geographical hazards of Martian terrain may impede a safe landing for science exploration spacecraft. Surface visualization software for hazard detection and avoidance may accordingly be applied in vehicles such as the Mars Exploration Rover (MER) to induce an autonomous and intelligent descent upon entering the planetary atmosphere. The focus of this project is to develop an image transformation algorithm for coordinate system matching between consecutive frames of terrain imagery taken throughout descent. The methodology involves integrating computer vision and graphics techniques, including affine transformation and projective geometry of an object, with the intrinsic parameters governing spacecraft dynamic motion and camera calibration.

  8. Planetary Camera imaging of the counter-rotating core galaxy NGC 4365

    NASA Technical Reports Server (NTRS)

    Forbes, Duncan A.

    1994-01-01

    We analyze F555W(V) band Planetary Camera images of NGC 4365, for which ground-based spectroscopy has revealed a misaligned, counter-rotating core. Line profile analysis by Surma indicates that the counter-rotating component has a disk structure. After deconvolution and galaxy modeling, we find photometric evidence, at small radii to support this claim. There is no indication of a central point source or dust lane. The surface brightness profile reveals a steep outer profile and shallow, by not flat, inner profile with the inflection radius occurring at 1.8 sec. The inner profile is consistent with a cusp.

  9. Evaluation of a large format image tube camera for the shuttle sortie mission

    NASA Technical Reports Server (NTRS)

    Tifft, W. C.

    1976-01-01

    A large format image tube camera of a type under consideration for use on the Space Shuttle Sortie Missions is evaluated. The evaluation covers the following subjects: (1) resolving power of the system (2) geometrical characteristics of the system (distortion etc.) (3) shear characteristics of the fiber optic coupling (4) background effects in the tube (5) uniformity of response of the tube (as a function of wavelength) (6) detective quantum efficiency of the system (7) astronomical applications of the system. It must be noted that many of these characteristics are quantitatively unique to the particular tube under discussion and serve primarily to suggest what is possible with this type of tube.

  10. Plume Imaging Using an IR Camera to Estimate Sulphur Dioxide Flux on Volcanoes of Northern Chile

    NASA Astrophysics Data System (ADS)

    Rosas Sotomayor, F.; Amigo, A.

    2014-12-01

    Remote sensing is a fast and safe method to obtain gas abundances in volcanic plumes, in particular when the access to the vent is difficult or during volcanic crisis. In recent years, a ground-based infrared camera (NicAir) has been developed by Nicarnica Aviation, which quantifies SO2 and ash on volcanic plumes, based on the infrared radiance at specific wavelengths through the application of filters. NicAir cameras have been acquired by the Geological Survey of Chile in order to study degassing of active volcanoes. This contribution focuses on series of measurements done in December 2013 in volcanoes of northern Chile, in particular Láscar, Irruputuncu and Ollagüe, which are characterized by persistent quiescent degassing. During fieldwork, plumes from all three volcanoes showed regular behavior and the atmospheric conditions were very favorable (cloud-free and dry air). Four, two and one sets of measurements, up to 100 images each, were taken for Láscar, Irruputuncu and Ollagüe volcano, respectively. Matlab software was used for image visualizing and processing of the raw data. For instance, data visualization is performed through Matlab IPT functions imshow() and imcontrast(), and one algorithm was created for extracting necessary metadata. Image processing considers radiation at 8.6 and 10 μm wavelengths, due to differential SO2 and water vapor absorption. Calibration was performed in the laboratory through a detector correlation between digital numbers (raw data in image pixel values) and spectral radiance, and also in the field considering the camera self-emissions of infrared radiation. A gradient between the plume core and plume rim is expected, due to quick reaction of sulphur dioxide with water vapor, therefore a flux underestimate is also expected. Results will be compared with other SO2 remote sensing instruments such as DOAS and UV-camera. The implementation of this novel technique in Chilean volcanoes will be a major advance in our

  11. Using the Standard Deviation of a Region of Interest in an Image to Estimate Camera to Emitter Distance

    PubMed Central

    Cano-García, Angel E.; Lazaro, José Luis; Infante, Arturo; Fernández, Pedro; Pompa-Chacón, Yamilet; Espinoza, Felipe

    2012-01-01

    In this study, a camera to infrared diode (IRED) distance estimation problem was analyzed. The main objective was to define an alternative to measures depth only using the information extracted from pixel grey levels of the IRED image to estimate the distance between the camera and the IRED. In this paper, the standard deviation of the pixel grey level in the region of interest containing the IRED image is proposed as an empirical parameter to define a model for estimating camera to emitter distance. This model includes the camera exposure time, IRED radiant intensity and the distance between the camera and the IRED. An expression for the standard deviation model related to these magnitudes was also derived and calibrated using different images taken under different conditions. From this analysis, we determined the optimum parameters to ensure the best accuracy provided by this alternative. Once the model calibration had been carried out, a differential method to estimate the distance between the camera and the IRED was defined and applied, considering that the camera was aligned with the IRED. The results indicate that this method represents a useful alternative for determining the depth information. PMID:22778608

  12. Correlating objective and subjective evaluation of texture appearance with applications to camera phone imaging

    NASA Astrophysics Data System (ADS)

    Phillips, Jonathan B.; Coppola, Stephen M.; Jin, Elaine W.; Chen, Ying; Clark, James H.; Mauer, Timothy A.

    2009-01-01

    Texture appearance is an important component of photographic image quality as well as object recognition. Noise cleaning algorithms are used to decrease sensor noise of digital images, but can hinder texture elements in the process. The Camera Phone Image Quality (CPIQ) initiative of the International Imaging Industry Association (I3A) is developing metrics to quantify texture appearance. Objective and subjective experimental results of the texture metric development are presented in this paper. Eight levels of noise cleaning were applied to ten photographic scenes that included texture elements such as faces, landscapes, architecture, and foliage. Four companies (Aptina Imaging, LLC, Hewlett-Packard, Eastman Kodak Company, and Vista Point Technologies) have performed psychophysical evaluations of overall image quality using one of two methods of evaluation. Both methods presented paired comparisons of images on thin film transistor liquid crystal displays (TFT-LCD), but the display pixel pitch and viewing distance differed. CPIQ has also been developing objective texture metrics and targets that were used to analyze the same eight levels of noise cleaning. The correlation of the subjective and objective test results indicates that texture perception can be modeled with an objective metric. The two methods of psychophysical evaluation exhibited high correlation despite the differences in methodology.

  13. Image disparity in cross-spectral face recognition: mitigating camera and atmospheric effects

    NASA Astrophysics Data System (ADS)

    Cao, Zhicheng; Schmid, Natalia A.; Li, Xin

    2016-05-01

    Matching facial images acquired in different electromagnetic spectral bands remains a challenge. An example of this type of comparison is matching active or passive infrared (IR) against a gallery of visible face images. When combined with cross-distance, this problem becomes even more challenging due to deteriorated quality of the IR data. As an example, we consider a scenario where visible light images are acquired at a short standoff distance while IR images are long range data. To address the difference in image quality due to atmospheric and camera effects, typical degrading factors observed in long range data, we propose two approaches that allow to coordinate image quality of visible and IR face images. The first approach involves Gaussian-based smoothing functions applied to images acquired at a short distance (visible light images in the case we analyze). The second approach involves denoising and enhancement applied to low quality IR face images. A quality measure tool called Adaptive Sharpness Measure is utilized as guidance for the quality parity process, which is an improvement of the famous Tenengrad method. For recognition algorithm, a composite operator combining Gabor filters, Local Binary Patterns (LBP), generalized LBP and Weber Local Descriptor (WLD) is used. The composite operator encodes both magnitude and phase responses of the Gabor filters. The combining of LBP and WLD utilizes both the orientation and intensity information of edges. Different IR bands, short-wave infrared (SWIR) and near-infrared (NIR), and different long standoff distances are considered. The experimental results show that in all cases the proposed technique of image quality parity (both approaches) benefits the final recognition performance.

  14. New Mars Camera's First Image of Mars from Mapping Orbit (Full Frame)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The high resolution camera on NASA's Mars Reconnaissance Orbiter captured its first image of Mars in the mapping orbit, demonstrating the full resolution capability, on Sept. 29, 2006. The High Resolution Imaging Science Experiment (HiRISE) acquired this first image at 8:16 AM (Pacific Time). With the spacecraft at an altitude of 280 kilometers (174 miles), the image scale is 25 centimeters per pixel (10 inches per pixel). If a person were located on this part of Mars, he or she would just barely be visible in this image.

    The image covers a small portion of the floor of Ius Chasma, one branch of the giant Valles Marineris system of canyons. The image illustrates a variety of processes that have shaped the Martian surface. There are bedrock exposures of layered materials, which could be sedimentary rocks deposited in water or from the air. Some of the bedrock has been faulted and folded, perhaps the result of large-scale forces in the crust or from a giant landslide. The image resolves rocks as small as small as 90 centimeters (3 feet) in diameter. It includes many dunes or ridges of windblown sand.

    This image (TRA_000823_1720) was taken by the High Resolution Imaging Science Experiment camera onboard the Mars Reconnaissance Orbiter spacecraft on Sept. 29, 2006. Shown here is the full image, centered at minus 7.8 degrees latitude, 279.5 degrees east longitude. The image is oriented such that north is to the top. The range to the target site was 297 kilometers (185.6 miles). At this distance the image scale is 25 centimeters (10 inches) per pixel (with one-by-one binning) so objects about 75 centimeters (30 inches) across are resolved. The image was taken at a local Mars time of 3:30 PM and the scene is illuminated from the west with a solar incidence angle of 59.7 degrees, thus the sun was about 30.3 degrees above the horizon. The season on Mars is northern winter, southern summer.

    [Photojournal note: Due to the large sizes of the high

  15. System for photometric calibration of optoelectronic imaging devices especially streak cameras

    DOEpatents

    Boni, Robert; Jaanimagi, Paul

    2003-11-04

    A system for the photometric calibration of streak cameras and similar imaging devices provides a precise knowledge of the camera's flat-field response as well as a mapping of the geometric distortions. The system provides the flat-field response, representing the spatial variations in the sensitivity of the recorded output, with a signal-to-noise ratio (SNR) greater than can be achieved in a single submicrosecond streak record. The measurement of the flat-field response is carried out by illuminating the input slit of the streak camera with a signal that is uniform in space and constant in time. This signal is generated by passing a continuous wave source through an optical homogenizer made up of a light pipe or pipes in which the illumination typically makes several bounces before exiting as a spatially uniform source field. The rectangular cross-section of the homogenizer is matched to the usable photocathode area of the streak tube. The flat-field data set is obtained by using a slow streak ramp that may have a period from one millisecond (ms) to ten seconds (s), but may be nominally one second in duration. The system also provides a mapping of the geometric distortions, by spatially and temporarily modulating the output of the homogenizer and obtaining a data set using the slow streak ramps. All data sets are acquired using a CCD camera and stored on a computer, which is used to calculate all relevant corrections to the signal data sets. The signal and flat-field data sets are both corrected for geometric distortions prior to applying the flat-field correction. Absolute photometric calibration is obtained by measuring the output fluence of the homogenizer with a "standard-traceable" meter and relating that to the CCD pixel values for a self-corrected flat-field data set.

  16. Minimal camera networks for 3D image based modeling of cultural heritage objects.

    PubMed

    Alsadik, Bashar; Gerke, Markus; Vosselman, George; Daham, Afrah; Jasim, Luma

    2014-01-01

    3D modeling of cultural heritage objects like artifacts, statues and buildings is nowadays an important tool for virtual museums, preservation and restoration. In this paper, we introduce a method to automatically design a minimal imaging network for the 3D modeling of cultural heritage objects. This becomes important for reducing the image capture time and processing when documenting large and complex sites. Moreover, such a minimal camera network design is desirable for imaging non-digitally documented artifacts in museums and other archeological sites to avoid disturbing the visitors for a long time and/or moving delicate precious objects to complete the documentation task. The developed method is tested on the Iraqi famous statue "Lamassu". Lamassu is a human-headed winged bull of over 4.25 m in height from the era of Ashurnasirpal II (883-859 BC). Close-range photogrammetry is used for the 3D modeling task where a dense ordered imaging network of 45 high resolution images were captured around Lamassu with an object sample distance of 1 mm. These images constitute a dense network and the aim of our study was to apply our method to reduce the number of images for the 3D modeling and at the same time preserve pre-defined point accuracy. Temporary control points were fixed evenly on the body of Lamassu and measured by using a total station for the external validation and scaling purpose. Two network filtering methods are implemented and three different software packages are used to investigate the efficiency of the image orientation and modeling of the statue in the filtered (reduced) image networks. Internal and external validation results prove that minimal image networks can provide highly accurate records and efficiency in terms of visualization, completeness, processing time (>60% reduction) and the final accuracy of 1 mm. PMID:24670718

  17. Minimal Camera Networks for 3D Image Based Modeling of Cultural Heritage Objects

    PubMed Central

    Alsadik, Bashar; Gerke, Markus; Vosselman, George; Daham, Afrah; Jasim, Luma

    2014-01-01

    3D modeling of cultural heritage objects like artifacts, statues and buildings is nowadays an important tool for virtual museums, preservation and restoration. In this paper, we introduce a method to automatically design a minimal imaging network for the 3D modeling of cultural heritage objects. This becomes important for reducing the image capture time and processing when documenting large and complex sites. Moreover, such a minimal camera network design is desirable for imaging non-digitally documented artifacts in museums and other archeological sites to avoid disturbing the visitors for a long time and/or moving delicate precious objects to complete the documentation task. The developed method is tested on the Iraqi famous statue “Lamassu”. Lamassu is a human-headed winged bull of over 4.25 m in height from the era of Ashurnasirpal II (883–859 BC). Close-range photogrammetry is used for the 3D modeling task where a dense ordered imaging network of 45 high resolution images were captured around Lamassu with an object sample distance of 1 mm. These images constitute a dense network and the aim of our study was to apply our method to reduce the number of images for the 3D modeling and at the same time preserve pre-defined point accuracy. Temporary control points were fixed evenly on the body of Lamassu and measured by using a total station for the external validation and scaling purpose. Two network filtering methods are implemented and three different software packages are used to investigate the efficiency of the image orientation and modeling of the statue in the filtered (reduced) image networks. Internal and external validation results prove that minimal image networks can provide highly accurate records and efficiency in terms of visualization, completeness, processing time (>60% reduction) and the final accuracy of 1 mm. PMID:24670718

  18. Efficient Smart CMOS Camera Based on FPGAs Oriented to Embedded Image Processing

    PubMed Central

    Bravo, Ignacio; Baliñas, Javier; Gardel, Alfredo; Lázaro, José L.; Espinosa, Felipe; García, Jorge

    2011-01-01

    This article describes an image processing system based on an intelligent ad-hoc camera, whose two principle elements are a high speed 1.2 megapixel Complementary Metal Oxide Semiconductor (CMOS) sensor and a Field Programmable Gate Array (FPGA). The latter is used to control the various sensor parameter configurations and, where desired, to receive and process the images captured by the CMOS sensor. The flexibility and versatility offered by the new FPGA families makes it possible to incorporate microprocessors into these reconfigurable devices, and these are normally used for highly sequential tasks unsuitable for parallelization in hardware. For the present study, we used a Xilinx XC4VFX12 FPGA, which contains an internal Power PC (PPC) microprocessor. In turn, this contains a standalone system which manages the FPGA image processing hardware and endows the system with multiple software options for processing the images captured by the CMOS sensor. The system also incorporates an Ethernet channel for sending processed and unprocessed images from the FPGA to a remote node. Consequently, it is possible to visualize and configure system operation and captured and/or processed images remotely. PMID:22163739

  19. Efficient smart CMOS camera based on FPGAs oriented to embedded image processing.

    PubMed

    Bravo, Ignacio; Baliñas, Javier; Gardel, Alfredo; Lázaro, José L; Espinosa, Felipe; García, Jorge

    2011-01-01

    This article describes an image processing system based on an intelligent ad-hoc camera, whose two principle elements are a high speed 1.2 megapixel Complementary Metal Oxide Semiconductor (CMOS) sensor and a Field Programmable Gate Array (FPGA). The latter is used to control the various sensor parameter configurations and, where desired, to receive and process the images captured by the CMOS sensor. The flexibility and versatility offered by the new FPGA families makes it possible to incorporate microprocessors into these reconfigurable devices, and these are normally used for highly sequential tasks unsuitable for parallelization in hardware. For the present study, we used a Xilinx XC4VFX12 FPGA, which contains an internal Power PC (PPC) microprocessor. In turn, this contains a standalone system which manages the FPGA image processing hardware and endows the system with multiple software options for processing the images captured by the CMOS sensor. The system also incorporates an Ethernet channel for sending processed and unprocessed images from the FPGA to a remote node. Consequently, it is possible to visualize and configure system operation and captured and/or processed images remotely. PMID:22163739

  20. Human Detection Based on the Generation of a Background Image and Fuzzy System by Using a Thermal Camera

    PubMed Central

    Jeon, Eun Som; Kim, Jong Hyun; Hong, Hyung Gil; Batchuluun, Ganbayar; Park, Kang Ryoung

    2016-01-01

    Recently, human detection has been used in various applications. Although visible light cameras are usually employed for this purpose, human detection based on visible light cameras has limitations due to darkness, shadows, sunlight, etc. An approach using a thermal (far infrared light) camera has been studied as an alternative for human detection, however, the performance of human detection by thermal cameras is degraded in case of low temperature differences between humans and background. To overcome these drawbacks, we propose a new method for human detection by using thermal camera images. The main contribution of our research is that the thresholds for creating the binarized difference image between the input and background (reference) images can be adaptively determined based on fuzzy systems by using the information derived from the background image and difference values between background and input image. By using our method, human area can be correctly detected irrespective of the various conditions of input and background (reference) images. For the performance evaluation of the proposed method, experiments were performed with the 15 datasets captured under different weather and light conditions. In addition, the experiments with an open database were also performed. The experimental results confirm that the proposed method can robustly detect human shapes in various environments. PMID:27043564

  1. Human Detection Based on the Generation of a Background Image and Fuzzy System by Using a Thermal Camera.

    PubMed

    Jeon, Eun Som; Kim, Jong Hyun; Hong, Hyung Gil; Batchuluun, Ganbayar; Park, Kang Ryoung

    2016-01-01

    Recently, human detection has been used in various applications. Although visible light cameras are usually employed for this purpose, human detection based on visible light cameras has limitations due to darkness, shadows, sunlight, etc. An approach using a thermal (far infrared light) camera has been studied as an alternative for human detection, however, the performance of human detection by thermal cameras is degraded in case of low temperature differences between humans and background. To overcome these drawbacks, we propose a new method for human detection by using thermal camera images. The main contribution of our research is that the thresholds for creating the binarized difference image between the input and background (reference) images can be adaptively determined based on fuzzy systems by using the information derived from the background image and difference values between background and input image. By using our method, human area can be correctly detected irrespective of the various conditions of input and background (reference) images. For the performance evaluation of the proposed method, experiments were performed with the 15 datasets captured under different weather and light conditions. In addition, the experiments with an open database were also performed. The experimental results confirm that the proposed method can robustly detect human shapes in various environments. PMID:27043564

  2. Breast Imaging Utilizing Dedicated Gamma Camera and (99m)Tc-MIBI: Experience at the Tel Aviv Medical Center and Review of the Literature Breast Imaging.

    PubMed

    Even-Sapir, Einat; Golan, Orit; Menes, Tehillah; Weinstein, Yuliana; Lerman, Hedva

    2016-07-01

    The scope of the current article is the clinical role of gamma cameras dedicated for breast imaging and (99m)Tc-MIBI tumor-seeking tracer, as both a screening modality among a healthy population and as a diagnostic modality in patients with breast cancer. Such cameras are now commercially available. The technology utilizing a camera composed of a NaI (Tl) detector is termed breast-specific gamma imaging. The technology of dual-headed camera composed of semiconductor cadmium zinc telluride detectors that directly converts gamma-ray energy into electronic signals is termed molecular breast imaging. Molecular breast imaging system has been installed at the Department of Nuclear medicine at the Tel Aviv Sourasky Medical Center, Tel Aviv in 2009. The article reviews the literature well as our own experience. PMID:27237439

  3. Control design for image tracking with an inertially stabilized airborne camera platform

    NASA Astrophysics Data System (ADS)

    Hurák, Zdenek; Rezáč, Martin

    2010-04-01

    The paper reports on a few control engineering issues related to design and implementation of an image-based pointing and tracking system for an inertially stabilized airborne camera platform. A medium-sized platform has been developed by the authors and a few more team members within a joint governmental project coordinated by Czech Air Force Research Institute. The resulting experimental platform is based on a common double gimbal configuration with two direct drive motors and off-the-shelf MEMS gyros. Automatic vision-based tracking system is built on top of the inertial stabilization. Choice of a suitable control configuration is discussed first, because the decoupled structure for the inner inertial rate controllers does not extend easily to the outer imagebased pointing and tracking loop. It appears that the pointing and tracking controller can benefit much from availability of measurements of an inertial rate of the camera around its optical axis. The proposed pointing and tracking controller relies on feedback linearization well known in image-based visual servoing. Simple compensation of a one sample delay introduced into the (slow) visual pointing and tracking loop by the computer vision system is proposed. It relies on a simple modification of the well-known Smith predictor scheme where the prediction takes advantage of availability of the (fast and undelayed) inertial rate measurements.

  4. Demonstration of near-infrared thermography with silicon image sensor cameras

    NASA Astrophysics Data System (ADS)

    Rotrou, Yann; Sentenac, Thierry; Le Maoult, Yannick; Magnan, Pierre; Farre, Jean A.

    2005-03-01

    This paper presents a thermal measurement system based on a Silicon image sensor camera operating in the Near Infrared spectral band (0.7-1.1 μm). The goal of the study is to develop a low-cost imaging system which provides an accurate measurement of temperature. A radiometric model is proposed to characterize the camera response by using physical parameters considering the specific spectral band used. After a calibration procedure of the model, measurements of black body temperatures ranging from 300 to 1000°C has been performed. The Noise Equivalent Temperature Difference (NETD) is lower than +/- 0.18°C at a black body temperature of 600°C. Accurate measurements are provided over the whole temperature range by introducing an automatic exposure time control. The exposure time is adjusted for each frame along the evolution of temperature in order to optimize the temperature sensitivity and the signal-to-noise ratio. The paper also describes the conversion process of the apparent black body temperature to the real temperature of the observed object using its emissivity and surface geometry. The overall method is depicted and the influence of each parameter is analyzed by computing the resulting temperature uncertainty. Finally, preliminary experimental results are presented for monitoring real temperature of moulds in a Super Forming Process (SPF).

  5. High-resolution imaging of the Pluto-Charon system with the Faint Object Camera of the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Albrecht, R.; Barbieri, C.; Adorf, H.-M.; Corrain, G.; Gemmo, A.; Greenfield, P.; Hainaut, O.; Hook, R. N.; Tholen, D. J.; Blades, J. C.

    1994-01-01

    Images of the Pluto-Charon system were obtained with the Faint Object Camera (FOC) of the Hubble Space Telescope (HST) after the refurbishment of the telescope. The images are of superb quality, allowing the determination of radii, fluxes, and albedos. Attempts were made to improve the resolution of the already diffraction limited images by image restoration. These yielded indications of surface albedo distributions qualitatively consistent with models derived from observations of Pluto-Charon mutual eclipses.

  6. Color video camera capable of 1,000,000 fps with triple ultrahigh-speed image sensors

    NASA Astrophysics Data System (ADS)

    Maruyama, Hirotaka; Ohtake, Hiroshi; Hayashida, Tetsuya; Yamada, Masato; Kitamura, Kazuya; Arai, Toshiki; Tanioka, Kenkichi; Etoh, Takeharu G.; Namiki, Jun; Yoshida, Tetsuo; Maruno, Hiromasa; Kondo, Yasushi; Ozaki, Takao; Kanayama, Shigehiro

    2005-03-01

    We developed an ultrahigh-speed, high-sensitivity, color camera that captures moving images of phenomena too fast to be perceived by the human eye. The camera operates well even under restricted lighting conditions. It incorporates a special CCD device that is capable of ultrahigh-speed shots while retaining its high sensitivity. Its ultrahigh-speed shooting capability is made possible by directly connecting CCD storages, which record video images, to photodiodes of individual pixels. Its large photodiode area together with the low-noise characteristic of the CCD contributes to its high sensitivity. The camera can clearly capture events even under poor light conditions, such as during a baseball game at night. Our camera can record the very moment the bat hits the ball.

  7. Charon's Color: A view from New Horizon Ralph/Multispectral Visible Imaging Camera

    NASA Astrophysics Data System (ADS)

    Olkin, C.; Howett, C.; Grundy, W. M.; Parker, A. H.; Ennico Smith, K.; Stern, S. A.; Binzel, R. P.; Cook, J. C.; Cruikshank, D. P.; Dalle Ore, C.; Earle, A. M.; Jennings, D. E.; Linscott, I.; Lunsford, A.; Parker, J. W.; Protopapa, S.; Reuter, D.; Singer, K. N.; Spencer, J. R.; Tsang, C.; Verbiscer, A.; Weaver, H. A., Jr.; Young, L. A.

    2015-12-01

    The Multispectral Visible Imaging Camera (MVIC; Reuter et al., 2008) is part of Ralph, an instrument on NASA's New Horizons spacecraft. MVIC is the color 'eyes' of New Horizons, observing objects using five bands from blue to infrared wavelengths. MVIC's images of Charon show it to be an intriguing place, a far cry from the grey heavily cratered world once postulated. Rather Charon is observed to have large surface areas free of craters, and a northern polar region that is much redder than its surroundings. This talk will describe these initial results in more detail, along with Charon's global geological color variations to put these results into their wider context. Finally possible surface coloration mechanisms due to global processes and/or seasonal cycles will be discussed.

  8. Position-sensitive detection of ultracold neutrons with an imaging camera and its implications to spectroscopy

    NASA Astrophysics Data System (ADS)

    Wei, Wanchun; Broussard, L. J.; Hoffbauer, M. A.; Makela, M.; Morris, C. L.; Tang, Z.; Adamek, E. R.; Callahan, N. B.; Clayton, S. M.; Cude-Woods, C.; Currie, S.; Dees, E. B.; Ding, X.; Geltenbort, P.; Hickerson, K. P.; Holley, A. T.; Ito, T. M.; Leung, K. K.; Liu, C.-Y.; Morley, D. J.; Ortiz, Jose D.; Pattie, R. W.; Ramsey, J. C.; Saunders, A.; Seestrom, S. J.; Sharapov, E. I.; Sjue, S. K.; Wexler, J.; Womack, T. L.; Young, A. R.; Zeck, B. A.; Wang, Zhehui

    2016-09-01

    Position-sensitive detection of ultracold neutrons (UCNs) is demonstrated using an imaging charge-coupled device (CCD) camera. A spatial resolution less than 15 μm has been achieved, which is equivalent to a UCN energy resolution below 2 pico-electron-volts through the relation δE =m0 gδx. Here, the symbols δE, δx, m0 and g are the energy resolution, the spatial resolution, the neutron rest mass and the gravitational acceleration, respectively. A multilayer surface convertor described previously is used to capture UCNs and then emits visible light for CCD imaging. Particle identification and noise rejection are discussed through the use of light intensity profile analysis. This method allows different types of UCN spectroscopy and other applications.

  9. The postcollapse core of M15 imaged with the HST planetary camera

    NASA Technical Reports Server (NTRS)

    Lauer, Tod R.; Holtzman, Jon A.; Faber, S. M.; Baum, William A.; Currie, Douglas G.; Ewald, S. P.; Groth, Edward J.; Hester, J. Jeff; Kelsall, T.

    1991-01-01

    It is shown here that, despite the severe spherical aberration present in the HST, the Wide Field/Planetary Camera (WFPC) images still present useful high-resolution information on M15, the classic candidate for a cluster with a collapsed core. The stars in M15 have been resolved down to the main-sequence turnoff and have been subtracted from the images. The remaining faint, unresolved stars form a diffuse background with a surprisingly large core with r(c) = 0.13 pc. The existence of a large core interior to the power-law cusp may imply that M15 has evolved well past maximum core collapse and may rule out the presence of a massive central black hole as well.

  10. Design and fabrication of MEMS-based thermally-actuated image stabilizer for cell phone camera

    NASA Astrophysics Data System (ADS)

    Lin, Chun-Ying; Chiou, Jin-Chern

    2012-11-01

    A micro-electro-mechanical system (MEMS)-based image stabilizer is proposed to counteracting shaking in cell phone cameras. The proposed stabilizer (dimensions, 8.8 × 8.8 × 0.2 mm3) includes a two-axis decoupling XY stage and has sufficient strength to suspend an image sensor (IS) used for anti-shaking function. The XY stage is designed to send electrical signals from the suspended IS by using eight signal springs and 24 signal outputs. The maximum actuating distance of the stage is larger than 25 μm, which is sufficient to resolve the shaking problem. Accordingly, the applied voltage for the 25 μm moving distance is lower than 20 V; the dynamic resonant frequency of the actuating device is 4485 Hz, and the rising time is 21 ms.

  11. Satellite Detection in AdvancedCamera for Surveys/Wide Field Channel Images

    NASA Astrophysics Data System (ADS)

    Borncamp, D.; Lim, Pey-Lian

    2016-01-01

    This document explains the process by which satellite trails can be found within individual chips of an Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) image. Since satellites are transient and sporadic events, we used the Hubble Frontier Fields (HFF) dataset which is manually checked for satellite trails has been used as a truth set to verify that the method in this document does a complete job without a high false positive rate. This document also details the process of producing a mask that will update data quality information to inform users where the trail traverses the image and properly account for the affected pixels. Along with this document, the Python source code used to detect and mask satellite trails will be released to users with as a stand-alone product within the STSDAS acstools package.

  12. A two camera video imaging system with application to parafoil angle of attack measurements

    NASA Astrophysics Data System (ADS)

    Meyn, Larry A.; Bennett, Mark S.

    1991-01-01

    This paper describes the development of a two-camera, video imaging system for the determination of three-dimensional spatial coordinates from stereo images. This system successfully measured angle of attack at several span-wise locations for large-scale parafoils tested in the NASA Ames 80- by 120-Foot Wind Tunnel. Measurement uncertainty for angle of attack was less than 0.6 deg. The stereo ranging system was the primary source for angle of attack measurements since inclinometers sewn into the fabric ribs of the parafoils had unknown angle offsets acquired during installation. This paper includes discussions of the basic theory and operation of the stereo ranging system, system measurement uncertainty, experimental set-up, calibration results, and test results. Planned improvements and enhancements to the system are also discussed.

  13. High-resolution Ceres High Altitude Mapping Orbit atlas derived from Dawn Framing Camera images

    NASA Astrophysics Data System (ADS)

    Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

    2016-09-01

    The Dawn spacecraft Framing Camera (FC) acquired over 2400 clear filter images of Ceres with a resolution of about 140 m/pixel during the six cycles in the High Altitude Mapping Orbit (HAMO) phase between August 18 and October 21, 2015. We ortho-rectified the images from the first cycle and produced a global, high-resolution, controlled photomosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 15 tiles mapped at a scale of 1:750,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The full atlas is available to the public through the Dawn Geographical Information System (GIS) web page

  14. Firefly: A HOT camera core for thermal imagers with enhanced functionality

    NASA Astrophysics Data System (ADS)

    Pillans, Luke; Harmer, Jack; Edwards, Tim

    2015-06-01

    Raising the operating temperature of mercury cadmium telluride infrared detectors from 80K to above 160K creates new applications for high performance infrared imagers by vastly reducing the size, weight and power consumption of the integrated cryogenic cooler. Realizing the benefits of Higher Operating Temperature (HOT) requires a new kind of infrared camera core with the flexibility to address emerging applications in handheld, weapon mounted and UAV markets. This paper discusses the Firefly core developed to address these needs by Selex ES in Southampton UK. Firefly represents a fundamental redesign of the infrared signal chain reducing power consumption and providing compatibility with low cost, low power Commercial Off-The-Shelf (COTS) computing technology. This paper describes key innovations in this signal chain: a ROIC purpose built to minimize power consumption in the proximity electronics, GPU based image processing of infrared video, and a software customisable infrared core which can communicate wirelessly with other Battlespace systems.

  15. Body-Based Gender Recognition Using Images from Visible and Thermal Cameras

    PubMed Central

    Nguyen, Dat Tien; Park, Kang Ryoung

    2016-01-01

    Gender information has many useful applications in computer vision systems, such as surveillance systems, counting the number of males and females in a shopping mall, accessing control systems in restricted areas, or any human-computer interaction system. In most previous studies, researchers attempted to recognize gender by using visible light images of the human face or body. However, shadow, illumination, and time of day greatly affect the performance of these methods. To overcome this problem, we propose a new gender recognition method based on the combination of visible light and thermal camera images of the human body. Experimental results, through various kinds of feature extraction and fusion methods, show that our approach is efficient for gender recognition through a comparison of recognition rates with conventional systems. PMID:26828487

  16. Real time plume and laser spot recognition in IR camera images

    SciTech Connect

    Moore, K.R.; Caffrey, M.P.; Nemzek, R.J.; Salazar, A.A.; Jeffs, J.; Andes, D.K.; Witham, J.C.

    1997-08-01

    It is desirable to automatically guide the laser spot onto the effluent plume for maximum IR DIAL system sensitivity. This requires the use of a 2D focal plane array. The authors have demonstrated that a wavelength-filtered IR camera is capable of 2D imaging of both the plume and the laser spot. In order to identify the centers of the plume and the laser spot, it is first necessary to segment these features from the background. They report a demonstration of real time plume segmentation based on velocity estimation. They also present results of laser spot segmentation using simple thresholding. Finally, they describe current research on both advanced segmentation and recognition algorithms and on reconfigurable real time image processing hardware based on field programmable gate array technology.

  17. Imaging system for cardiac planar imaging using a dedicated dual-head gamma camera

    SciTech Connect

    Majewski, Stanislaw; Umeno, Marc M.

    2011-09-13

    A cardiac imaging system employing dual gamma imaging heads co-registered with one another to provide two dynamic simultaneous views of the heart sector of a patient torso. A first gamma imaging head is positioned in a first orientation with respect to the heart sector and a second gamma imaging head is positioned in a second orientation with respect to the heart sector. An adjustment arrangement is capable of adjusting the distance between the separate imaging heads and the angle between the heads. With the angle between the imaging heads set to 180 degrees and operating in a range of 140-159 keV and at a rate of up to 500kHz, the imaging heads are co-registered to produce simultaneous dynamic recording of two stereotactic views of the heart. The use of co-registered imaging heads maximizes the uniformity of detection sensitivity of blood flow in and around the heart over the whole heart volume and minimizes radiation absorption effects. A normalization/image fusion technique is implemented pixel-by-corresponding pixel to increase signal for any cardiac region viewed in two images obtained from the two opposed detector heads for the same time bin. The imaging system is capable of producing enhanced first pass studies, bloodpool studies including planar, gated and non-gated EKG studies, planar EKG perfusion studies, and planar hot spot imaging.

  18. A methodology to extract dimensional information from steel bars using a magnetic field imaging camera (mFIC)

    NASA Astrophysics Data System (ADS)

    Heathcote, L.; Gaydecki, P.

    2010-07-01

    A methodology to estimate the depth and diameter of steel rebars is presented using information obtained from scans generated by a magnetic field imaging camera (mFIC). A raw image of the steel rebars is obtained from the camera. The methodology makes use of the properties of an image produced using the magnetic field generated by a large stationary square coil. The methodology has been used to write a Labview program showing bar location and arrangement. It has generated accurate dimensional information to a depth of 10 cm, including from bars not used as data to develop the method. Additionally, the method does not appear to show degradation with increasing bar depth.

  19. A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M

    SciTech Connect

    von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W.; Jones, S.; Paoletti, F.; Petravich, G.; Rimini, F.

    1993-05-01

    During lower hybrid current drive (LHCD), suprathermal electrons are generated that emit hard X-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 {times} 128 pixel images of the bremsstrahlung with a 3 ms time resolution. This camera has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. The detector is a 9in. dia. intensifier. A detailed account of the construction of the Hard X-ray Camera, its operation, and its performance is given.

  20. A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M

    SciTech Connect

    von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W. . Plasma Physics Lab.); Jones, S.; Paoletti, F. . Plasma Fusion Center); Petravich, G. . Central Research Inst. for Physics); Rimini,

    1993-05-01

    During lower hybrid current drive (LHCD), suprathermal electrons are generated that emit hard X-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 [times] 128 pixel images of the bremsstrahlung with a 3 ms time resolution. This camera has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. The detector is a 9in. dia. intensifier. A detailed account of the construction of the Hard X-ray Camera, its operation, and its performance is given.

  1. Applications and Imaging Techniques of a Si/CdTe Compton Gamma-Ray Camera

    NASA Astrophysics Data System (ADS)

    Takeda, Shin'ichiro; Ichinohe, Yuto; Hagino, Kouichi; Odaka, Hirokazu; Yuasa, Takayuki; Ishikawa, Shin-nosuke; Fukuyama, Taro; Saito, Shinya; Sato, Tamotsu; Sato, Goro; Watanabe, Shin; Kokubun, Motohide; Takahashi, Tadayuki; Yamaguchi, Mitsutaka; Tajima, Hiroyasu; Tanaka, Takaaki; Nakazawa, Kazuhiro; Fukazawa, Yasushi; Nakano, Takashi

    By using a new Compton camera consisting of a silicon double-sided strip detector (Si-DSD) and a CdTe doublesided strip detector (CdTe-DSD), originally developed for the ASTRO-H satellite mission, an experiment involving imaging radioisotopes was conducted to study their feasibility for hotspot monitoring. In addition to the hotspot imaging already provided by commercial imaging systems, identification of various radioisotopes is possible thanks to the good energy resolution obtained by the semiconductor detectors. Three radioisotopes of 133Ba (356 keV), 22Na (511 keV) and 137Cs (662 keV) were individually imaged by applying event selection in the energy window and the gamma-ray images were correctly overlapped by an optical picture. Detection efficiency of 1.68 ×10-4 (effective area: 1.7×10-3 cm2) and angular resolution of 3.8 degrees were obtained by stacking five detector modules for a 662 keV gamma ray. The higher detection efficiency required in specific use can be achieved by stacking more detector modules.

  2. Performance of the Aspect Camera Assembly for the Advanced X-Ray Astrophysics Facility: Imaging

    NASA Technical Reports Server (NTRS)

    Michaels, Dan

    1998-01-01

    The Aspect Camera Assembly (ACA) is a "state-of-the-art" star tracker that provides real-time attitude information to the Advanced X-Ray Astrophysics Facility - Imaging (AXAF-I), and provides imaging data for "post-facto" ground processing. The ACA consists of a telescope with a CCD focal plane, associated focal plane read-out electronics, and an on-board processor that processes the focal plane data to produce star image location reports. On-board star image locations are resolved to 0.8 arcsec, and post-facto algorithms yield 0.2 arcsec star location accuracies (at end of life). The protoflight ACA has been built, along with a high accuracy vacuum test facility. Image position determination has been verified to < 0.2 arcsec accuracies. This paper is a follow-on paper to one presented by the author at the AeroSense '95 conference. This paper presents the "as built" configuration, the tested performance, and the test facility's design and demonstrated accuracy. The ACA has been delivered in anticipation of a August, 1998 shuttle launch.

  3. A Compton scatter camera for spectral imaging of 0.5 to 3.0 MeV gamma rays

    SciTech Connect

    Martin, J.B.

    1994-12-31

    A prototype Compton scatter camera for imaging gamma rays has been built and tested. This camera addresses unique aspects of gamma-ray imaging at nuclear industrial sites, including gamma-ray energies in the 0.5 to 3.0 MeV range and polychromatic fields. Analytic models of camera efficiency, resolution and contaminating events are developed. The response of the camera bears strong similarity to emission computed tomography devices used in nuclear medicine. A direct Fourier based algorithm is developed to reconstruct two-dimensional images of measured gamma-ray fields. Iterative ART and MLE algorithms are also investigated. The point response of the camera to gamma rays of energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms are also investigated. The point response of the camera to gamma rays energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms and produces images that are, in general, of the same quality. Measured images of several phantoms are shown. Important results include angular resolutions as low as 4.4{degrees}, reproduction of phantom size and position within 7%, and contrast recovery of 84% or better. Spectral imaging is demonstrated with independent images from a multi-energy phantom consisting of two sources imaged simultaneously.

  4. Improved Digitization of Lunar Mare Ridges with LROC Derived Products

    NASA Astrophysics Data System (ADS)

    Crowell, J. M.; Robinson, M. S.; Watters, T. R.; Bowman-Cisneros, E.; Enns, A. C.; Lawrence, S.

    2011-12-01

    Lunar wrinkle ridges (mare ridges) are positive-relief structures formed from compressional stress in basin-filling flood basalt deposits [1]. Previous workers have measured wrinkle ridge orientations and lengths to investigate their spatial distribution and infer basin-localized stress fields [2,3]. Although these plots include the most prominent mare ridges and their general trends, they may not have fully captured all of the ridges, particularly the smaller-scale ridges. Using Lunar Reconnaissance Orbiter Wide Angle Camera (WAC) global mosaics and derived topography (100m pixel scale) [4], we systematically remapped wrinkle ridges in Mare Serenitatis. By comparing two WAC mosaics with different lighting geometry, and shaded relief maps made from a WAC digital elevation model (DEM) [5], we observed that some ridge segments and some smaller ridges are not visible in previous structure maps [2,3]. In the past, mapping efforts were limited by a fixed Sun direction [6,7]. For systematic mapping we created three shaded relief maps from the WAC DEM with solar azimuth angles of 0°, 45°, and 90°, and a fourth map was created by combining the three shaded reliefs into one, using a simple averaging scheme. Along with the original WAC mosaic and the WAC DEM, these four datasets were imported into ArcGIS, and the mare ridges of Imbrium, Serenitatis, and Tranquillitatis were digitized from each of the six maps. Since the mare ridges are often divided into many ridge segments [8], each major component was digitized separately, as opposed to the ridge as a whole. This strategy enhanced our ability to analyze the lengths, orientations, and abundances of these ridges. After the initial mapping was completed, the six products were viewed together to identify and resolve discrepancies in order to produce a final wrinkle ridge map. Comparing this new mare ridge map with past lunar tectonic maps, we found that many mare ridges were not recorded in the previous works. It was noted

  5. Implementing PET-guided biopsy: integrating functional imaging data with digital x-ray mammography cameras

    NASA Astrophysics Data System (ADS)

    Weinberg, Irving N.; Zawarzin, Valera; Pani, Roberto; Williams, Rodney C.; Freimanis, Rita L.; Lesko, Nadia M.; Levine, E. A.; Perrier, N.; Berg, Wendie A.; Adler, Lee P.

    2001-05-01

    Purpose: Phantom trials using the PET data for localization of hot spots have demonstrated positional accuracies in the millimeter range. We wanted to perform biopsy based on information from both anatomic and functional imaging modalities, however we had a communication challenge. Despite the digital nature of DSM stereotactic X-ray mammography devices, and the large number of such devices in Radiology Departments (approximately 1600 in the US alone), we are not aware of any methods of connecting stereo units to other computers in the Radiology department. Methods: We implemented a local network between an external IBM PC (running Linux) and the Lorad Stereotactic Digital Spot Mammography PC (running DOS). The application used IP protocol on the parallel port, and could be run in the background on the LORAD PC without disrupting important clinical activities such as image acquisition or archiving. With this software application, users of the external PC could pull x-ray images on demand form the Load DSM computer. Results: X-ray images took about a minute to ship to the external PC for analysis or forwarding to other computers on the University's network. Using image fusion techniques we were able to designate locations of functional imaging features as the additional targets on the anatomic x-rays. These pseudo-features could then potentially be used to guide biopsy using the stereotactic gun stage on the Lorad camera. New Work to be Presented: A method of transferring and processing stereotactic x-ray mammography images to a functional PET workstation for implementing image-guided biopsy.

  6. SU-C-18A-02: Image-Based Camera Tracking: Towards Registration of Endoscopic Video to CT

    SciTech Connect

    Ingram, S; Rao, A; Wendt, R; Castillo, R; Court, L; Yang, J; Beadle, B

    2014-06-01

    Purpose: Endoscopic examinations are routinely performed on head and neck and esophageal cancer patients. However, these images are underutilized for radiation therapy because there is currently no way to register them to a CT of the patient. The purpose of this work is to develop a method to track the motion of an endoscope within a structure using images from standard clinical equipment. This method will be incorporated into a broader endoscopy/CT registration framework. Methods: We developed a software algorithm to track the motion of an endoscope within an arbitrary structure. We computed frame-to-frame rotation and translation of the camera by tracking surface points across the video sequence and utilizing two-camera epipolar geometry. The resulting 3D camera path was used to recover the surrounding structure via triangulation methods. We tested this algorithm on a rigid cylindrical phantom with a pattern spray-painted on the inside. We did not constrain the motion of the endoscope while recording, and we did not constrain our measurements using the known structure of the phantom. Results: Our software algorithm can successfully track the general motion of the endoscope as it moves through the phantom. However, our preliminary data do not show a high degree of accuracy in the triangulation of 3D point locations. More rigorous data will be presented at the annual meeting. Conclusion: Image-based camera tracking is a promising method for endoscopy/CT image registration, and it requires only standard clinical equipment. It is one of two major components needed to achieve endoscopy/CT registration, the second of which is tying the camera path to absolute patient geometry. In addition to this second component, future work will focus on validating our camera tracking algorithm in the presence of clinical imaging features such as patient motion, erratic camera motion, and dynamic scene illumination.