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1

LROC - Lunar Reconnaissance Orbiter Camera  

NASA Astrophysics Data System (ADS)

The Lunar Reconnaissance Orbiter Camera (LROC) is designed to address two of the prime LRO measurement requirements. 1) Assess meter and smaller-scale features to facilitate safety analysis for potential lunar landing sites near polar resources, and elsewhere on the Moon. 2) Acquire multi-temporal synoptic imaging of the poles every orbit 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. The LROC consists of two narrow-angle camera components (NACs) to provide 0.5-m scale panchromatic images over a 5-km swath, a wide-angle camera component (WAC) to provide images at a scale of 100 and 400 m in seven color bands over a 100-km swath, and a common Sequence and Compressor System (SCS). In addition to acquiring the two LRO prime measurement sets, LROC will return six other high-value datasets that support LRO goals, the Robotic Lunar Exploration Program (RLEP), and basic lunar science. These additional datasets include: 3) meter-scale mapping of regions of permanent or near-permanent illumination of polar massifs; 4) multiple co-registered observations of portions of potential landing sites and elsewhere for derivation of high-resolution topography through stereogrammetric and photometric stereo analyses; 5) a global multispectral map in 7 wavelengths (300-680 nm) to characterize lunar resources, in particular ilmenite; 6) a global 100-m/pixel basemap with incidence angles (60-80°) favorable for morphologic interpretations; 7) sub-meter imaging of a variety of geologic units to characterize physical properties, variability of the regolith, and key science questions; and 8) meter-scale coverage overlapping with Apollo era Panoramic images (1-2 m/pixel) to document the number of small impacts since 1971-1972, to ascertain hazards for future surface operations and interplanetary travel.

Robinson, M. S.; Bowman-Cisneros, E.; Brylow, S. M.; Eliason, E.; Hiesinger, H.; Jolliff, B. L.; McEwen, A. S.; Malin, M. C.; Roberts, D.; Thomas, P. C.; Turtle, E.

2006-12-01

2

NASA's Lunar Reconnaissance Orbiter Cameras (LROC)  

NASA Astrophysics Data System (ADS)

The Lunar Reconnaissance Orbiter LRO mission is scheduled to launch in the fall of 2008 as part of NASA s Robotic Lunar Exploration Program and is the first spacecraft to be built as part of NASA s Vision for Space Exploration The orbiter will be equipped with seven scientific instrument packages one of which is LROC The Lunar Reconnaissance Orbiter Camera LROC has been designed to address two of LRO s primary measurement objectives landing site certification and monitoring of polar illumination In order to examine potential landing sites high-resolution images 0 5 m pixel will be used to assess meter-scale features near the pole and other regions on the lunar surface The LROC will also acquire 100 m pixel images of the polar regions of the Moon during each orbit for a year to identify areas of permanent shadow and permanent or near-permanent illumination In addition to these two main objectives the LROC team also plans to conduct meter-scale monitoring of polar regions under varying illumination angles acquire overlapping observations to enable derivation of meter-scale topography acquire global multispectral imaging to map ilmenite and other minerals derive a global morphology base map characterize regolith properties and determine current impact hazards by re-imaging areas covered by Apollo images to search for newly-formed impact craters The LROC is a modified version of the Mars Reconnaissance Orbiter s Context Camera and Mars Color Imager The LROC will be made up of four optical elements two identical narrow-angle telescopes

Robinson, M.; McEwen, A.; Eliason, E.; Joliff, B.; Hiesinger, H.; Malin, M.; Thomas, P.; Turtle, E.; Brylow, S.

3

Lunar Reconnaissance Orbiter Camera (LROC) Instrument Overview  

Microsoft Academic Search

The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NACs) are on the NASA Lunar\\u000a Reconnaissance Orbiter (LRO). The WAC is a 7-color push-frame camera (100 and 400 m\\/pixel visible and UV, respectively), while\\u000a the two NACs are monochrome narrow-angle linescan imagers (0.5 m\\/pixel). The primary mission of LRO is to obtain measurements\\u000a of the Moon that

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

2010-01-01

4

Photometric normalization of LROC WAC images  

Microsoft Academic Search

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

H. Sato; B. Denevi; M. S. Robinson; B. W. Hapke; A. S. McEwen

2010-01-01

5

NASA's Lunar Reconnaissance Orbiter Cameras (LROC)  

Microsoft Academic Search

The Lunar Reconnaissance Orbiter LRO mission is scheduled to launch in the fall of 2008 as part of NASA s Robotic Lunar Exploration Program and is the first spacecraft to be built as part of NASA s Vision for Space Exploration The orbiter will be equipped with seven scientific instrument packages one of which is LROC The Lunar Reconnaissance Orbiter

M. Robinson; A. McEwen; E. Eliason; B. Joliff; H. Hiesinger; M. Malin; P. Thomas; E. Turtle; S. Brylow

2006-01-01

6

Photometric normalization of LROC WAC images  

NASA Astrophysics Data System (ADS)

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 variability of the regolith from region to region. As the fitting area increases, the accuracy of curve fitting decreases due to the larger variety of albedo, topography, and composition. Thus we have adopted an albedo-dependent photometric normalization routine. Phase curves are derived for discreet bins of preliminary normalized reflectance calculated from Clementine global mosaic in a fitting area that is composed of predominantly mare in Oceanus Procellarum. The global WAC mosaic was then corrected pixel-by-pixel according to its preliminary reflectance map with satisfactory results. We observed that the phase curves per normalized-reflectance bins become steeper as the reflectance value increases. Further filtering by using FeO, TiO2, or optical maturity [5] for parameter calculations may help elucidate the effects of surface composition and maturity on photometric properties of the surface. [1] Hapke, B.W. (1993) Theory of Reflectance and Emittance Spectroscopy, Cambridge Univ. Press. [2] Schoenberg (1925) Ada. Soc. Febb., vol. 50. [3] Hillier et al. (1999) Icarus 141, 205-225. [4] McEwen (1991) Icarus 92, 298-311. [5] Lucey et al. (2000) JGR, v105, no E8, p20377-20386.

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

2010-12-01

7

Preliminary Mapping of Permanently Shadowed and Sunlit Regions Using the Lunar Reconnaissance Orbiter Camera (LROC)  

NASA Astrophysics Data System (ADS)

The spin axis of the Moon is tilted by only 1.5° (compared with the Earth's 23.5°), leaving some areas near the poles in permanent shadow while other nearby regions remain sunlit for a majority of the year. Theory, radar data, neutron measurements, and Lunar CRater Observation and Sensing Satellite (LCROSS) observations suggest that volatiles may be present in the cold traps created inside these permanently shadowed regions. While areas of near permanent illumination are prime locations for future lunar outposts due to benign thermal conditions and near constant solar power. The Lunar Reconnaissance Orbiter (LRO) has two imaging systems that provide medium and high resolution views of the poles. During almost every orbit the LROC Wide Angle Camera (WAC) acquires images at 100 m/pixel of the polar region (80° to 90° north and south latitude). In addition, the LROC Narrow Angle Camera (NAC) targets selected regions of interest at 0.7 to 1.5 m/pixel [Robinson et al., 2010]. During the first 11 months of the nominal mission, LROC acquired almost 6,000 WAC images and over 7,300 NAC images of the polar region (i.e., within 2° of pole). By analyzing this time series of WAC and NAC images, regions of permanent shadow and permanent, or near-permanent illumination can be quantified. The LROC Team is producing several reduced data products that graphically illustrate the illumination conditions of the polar regions. Illumination movie sequences are being produced that show how the lighting conditions change over a calendar year. Each frame of the movie sequence is a polar stereographic projected WAC image showing the lighting conditions at that moment. With the WAC’s wide field of view (~100 km at an altitude of 50 km), each frame has repeat coverage between 88° and 90° at each pole. The same WAC images are also being used to develop multi-temporal illumination maps that show the percent each 100 m × 100 m area is illuminated over a period of time. These maps are derived by stacking all the WAC frames, selecting a threshold to determine if the surface is illuminated, and summing the resulting binary images. In addition, mosaics of NAC images are also being produced for regions of interest at a scale of 0.7 to 1.5 m/pixel. The mosaics produced so far have revealed small illuminated surfaces on the tens of meters scale that were previously thought to be shadowed during that time. The LROC dataset of the polar regions complements previous illumination analysis of Clementine images [Bussey et al., 1999], Kaguya topography [Bussey et al., 2010], and the current efforts underway by the Lunar Orbiter Laser Altimeter (LOLA) Team [Mazarico et al., 2010] and provide an important new dataset for science and exploration. References: Bussey et al. (1999), Illumination conditions at the lunar south pole, Geophysical Research Letters, 26(9), 1187-1190. Bussey et al. (2010), Illumination conditions of the south pole of the Moon derived from Kaguya topography, Icarus, 208, 558-564. Mazarico et al. (2010), Illumination of the lunar poles from the Lunar Orbiter Laser Altimeter (LOLA) Topography Data, paper presented at 41st LPSC, Houston, TX. Robinson et al. (2010), Lunar Reconnaissance Orbiter Camera (LROC) Instrument Overview, Space Sci Rev, 150, 81-124.

Speyerer, E.; Koeber, S.; Robinson, M. S.

2010-12-01

8

Characterization of Previously Unidentified Lunar Pyroclastic Deposits using Lunar Reconnaissance Orbiter Camera (LROC) Data  

NASA Astrophysics Data System (ADS)

We used a Lunar Reconnaissance Orbiter Cameras (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, 13 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. A significant new finding is the discovery of localized pyroclastic deposits within floor-fractured craters Anderson E & F on the lunar farside, isolated from other known similar deposits. These appear to be Alphonsus-type deposits erupted from a series of small vents aligned with the fracture system, suggesting their origin in volatile-rich vulcanian-style eruptions containing relatively small amounts of juvenile material. The presence of such volcanic features on the lunar farside outside of the major basins such as Moscoviense, Orientale, and South Pole - Aitken indicates that magma ascent and eruption have occurred even in the central farside highlands, despite the thicker farside crust. However, this is the only such occurrence that we have located, and it appears to represent an endpoint in the continuum of eruption styles where the eruption was just barely able to reach the surface but could not transport enough magma to the surface to form an effusive deposit. Many of the 47 potential locations screened were eliminated from consideration based on inconclusive evidence regarding their mode of emplacement. Additional optical imaging, or analyses of other data sets such as radar, imaging spectroscopy, or thermal inertia, could result in identification of additional pyroclastic deposits, especially lighter-toned deposits. However, our search also confirms that most major regional and localized pyroclastic deposits have likely been identified on the Moon down to ~100 m/pix resolution, and that additional newly identified pyroclastic deposits are likely to be either isolated small deposits or additional portions of discontinuous, patchy deposits. Based on the locations where we identified previously unidentified pyroclastic deposits, the greatest potential for identification of additional pyroclastic deposits is likely to be in regions with other volcanic constructs associated with mare deposits, highland locations along the margins of maria, and smaller floor-fractured craters that have not yet been thoroughly imaged at higher resolution, particularly on the farside (such as Anderson E & F).

Gustafson, O.; Bell, J. F.; Gaddis, L. R.; Hawke, B. R.; Giguere, T.

2011-12-01

9

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

NASA Astrophysics Data System (ADS)

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 the number of small impacts since 1971-1972. LROC allows us to determine the recent impact rate of bolides in the size range of 0.5 to 10 meters, which is currently not well known. Determining the impact rate at these sizes enables engineering remediation measures for future surface operations and interplanetary travel. The WAC has imaged nearly the entire Moon in seven wavelengths. A preliminary global WAC stereo-based topographic model is in preparation [1] and global color processing is underway [2]. As the mission progresses repeat global coverage will be obtained as lighting conditions change providing a robust photometric dataset. The NACs are revealing a wealth of morpho-logic features at the meter scale providing the engineering and science constraints needed to support future lunar exploration. All of the Apollo landing sites have been imaged, as well as the majority of robotic landing and impact sites. Through the use of off-nadir slews a collection of stereo pairs is being acquired that enable 5-m scale topographic mapping [3-7]. Impact mor-phologies (terraces, impact melt, rays, etc) are preserved in exquisite detail at all Copernican craters and are enabling new studies of impact mechanics and crater size-frequency distribution measurements [8-12]. Other topical studies including, for example, lunar pyroclastics, domes, and tectonics are underway [e.g., 10-17]. The first PDS data release of LROC data will be in March 2010, and will include all images from the commissioning phase and the first 3 months of the mapping phase. [1] Scholten et al. (2010) 41st LPSC, #2111; [2] Denevi et al. (2010a) 41st LPSC, #2263; [3] Beyer et al. (2010) 41st LPSC, #2678; [4] Archinal et al. (2010) 41st LPSC, #2609; [5] Mattson et al. (2010) 41st LPSC, #1871; [6] Tran et al. (2010) 41st LPSC, #2515; [7] Oberst et al. (2010) 41st LPSC, #2051; [8] Bray et al. (2010) 41st LPSC, #2371; [9] Denevi et al. (2010b) 41st LPSC, #2582; [10] Hiesinger et al. (2010a) 41st LPSC, #2278; [11] Hiesinger et al. (2010b) 41st LPSC, #2304; [12] van der Bogert et al. (2010) 41st LPSC, #2165;

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

10

LROC Stereo Observations  

NASA Astrophysics Data System (ADS)

The Lunar Reconnaissance Orbiter Camera (LROC) will obtain two types of multiple overlapping coverage to derive terrain models of the lunar surface. LROC has two Narrow Angle Cameras (NACs), working jointly to provide a wider (in the cross-track direction) field of view, as well as a Wide Angle Camera (WAC). LRO's orbit precesses, and the same target can be viewed at different solar azimuth and incidence angles providing the opportunity to acquire `photometric stereo' in addition to traditional `geometric stereo' data. Geometric stereo refers to images acquired by LROC with two observations at different times. They must have different emission angles to provide a stereo convergence angle such that the resultant images have enough parallax for a reasonable stereo solution. The lighting at the target must not be radically different. If shadows move substantially between observations, it is very difficult to correlate the images. The majority of NAC geometric stereo will be acquired with one nadir and one off-pointed image (20 degree roll). Alternatively, pairs can be obtained with two spacecraft rolls (one to the left and one to the right) providing a stereo convergence angle up to 40 degrees. Overlapping WAC images from adjacent orbits can be used to generate topography of near-global coverage at kilometer-scale effective spatial resolution. Photometric stereo refers to multiple-look observations of the same target under different lighting conditions. LROC will acquire at least three (ideally five) observations of a target. These observations should have near identical emission angles, but with varying solar azimuth and incidence angles. These types of images can be processed via various methods to derive single pixel resolution topography and surface albedo. The LROC team will produce some topographic models, but stereo data collection is focused on acquiring the highest quality data so that such models can be generated later.

Beyer, Ross A.; Archinal, B.; Li, R.; Mattson, S.; Moratto, Z.; McEwen, A.; Oberst, J.; Robinson, M.

2009-09-01

11

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

Microsoft Academic Search

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

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

2006-01-01

12

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

NASA Astrophysics Data System (ADS)

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.

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

2012-03-01

13

Nonparametric ROC and LROC analysis  

SciTech Connect

In this paper we review several results of the nonparametric receiver operating characteristic (ROC) analysis and present an extension to the nonparametric localization ROC (LROC) analysis. Equations for the estimation of the area under the characteristic curve and for the variance calculations are derived. Expressions for the choice of the optimal ratio between the number of signal-absent and signal-present image samples are also presented. The results can be applied both with continuous or discrete scoring scales. The simulation studies carried out validate the theoretical derivations and show that the LROC analysis is considerably more sensitive than the ROC analysis.

Popescu, Lucretiu M. [University of Pennsylvania, Department of Radiology, 423 Guardian Drive, 4th floor Blockley Hall, Philadelphia, PA 19104-6021 (United States)

2007-05-15

14

Stardust Imaging Camera  

Microsoft Academic Search

The Stardust spacecraft is carrying an Imaging Camera, primarily for 81P\\/Wild 2 approach navigation, but the camera also will provide valuable data for P\\/Wild 2 nucleus characterization and about its activity. During an engineering readiness test, the camera already has provided useful scientific data about an asteroid, 5535 Annefrank. The camera utilizes spare parts from Cassini and Voyager as well

Ray L. Newburn Jr; Shyam Bhaskaran; Thomas C. Duxbury; George Fraschetti; Tom Radey; Mark Schwochert

2003-01-01

15

Exploring the Moon with LROC-NAC Stereo Anaglyphs  

NASA Astrophysics Data System (ADS)

The Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) operating on the Lunar Reconnaissance Orbiter (LRO), has returned over 500,000 high resolution images of the surface of the Moon since 2009 [1]. The NAC acquires geometric stereo image pairs of the same surface target on subsequent orbits by rolling the spacecraft off-nadir to achieve stereo convergence. Stereo pairs are generally acquired close in time (2 to 4 hrs), to minimize photometric differences. An anaglyph is a qualitative stereo visualization product formed by putting one image from the stereo pair in the red channel, and the other image in the blue and green channels, so that together the pair can be viewed in 3D using red-blue or red-cyan glasses. LROC NAC anaglyphs are produced automatically, so the stereo information is readily interpretable, in a qualitative sense, without the need for intensive computational and personnel resources, such as is required to make digital terrain models (DTM).

Mattson, S.; McEwen, A. S.; Robinson, M. S.; Speyerer, E.; Archinal, B.

2012-09-01

16

Mapping the Apollo 17 Astronauts' Positions Based on LROC Data and Apollo Surface Photography  

NASA Astrophysics Data System (ADS)

The positions from where the Apollo 17 astronauts recorded panoramic image series, e.g. at the so-called "traverse stations", were precisely determined using ortho-images (0.5 m/pxl) as well as Digital Terrain Models (DTM) (1.5 m/pxl and 100 m/pxl) derived from Lunar Reconnaissance Orbiter Camera (LROC) data. Features imaged in the Apollo panoramas were identified in LROC ortho-images. Least-squares techniques were applied to angles measured in the panoramas to determine the astronaut's position to within the ortho-image pixel. The result of our investigation of Traverse Station 1 in the north-west of Steno Crater is presented.

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

2011-10-01

17

Combined collimator/reconstruction optimization for myocardial perfusion SPECT imaging using polar map-based LROC numerical observer  

NASA Astrophysics Data System (ADS)

Polar maps have been used to assist clinicians diagnose coronary artery diseases (CAD) in single photon emission computed tomography (SPECT) myocardial perfusion imaging. Herein, we investigate the optimization of collimator design for perfusion defect detection in SPECT imaging when reconstruction includes modeling of the collimator. The optimization employs an LROC clinical model observer (CMO), which emulates the clinical task of polar map detection of CAD. By utilizing a CMO, which better mimics the clinical perfusion-defect detection task than previous SKE based observers, our objective is to optimize collimator design for SPECT myocardial perfusion imaging when reconstruction includes compensation for collimator spatial resolution. Comparison of lesion detection accuracy will then be employed to determine if a lower spatial resolution hence higher sensitivity collimator design than currently recommended could be utilized to reduce the radiation dose to the patient, imaging time, or a combination of both. As the first step in this investigation, we report herein on the optimization of the three-dimensional (3D) post-reconstruction Gaussian filtering of and the number of iterations used to reconstruct the SPECT slices of projections acquired by a low-energy generalpurpose (LEGP) collimator. The optimization was in terms of detection accuracy as determined by our CMO and four human observers. Both the human and all four CMO variants agreed that the optimal post-filtering was with sigma of the Gaussian in the range of 0.75 to 1.0 pixels. In terms of number of iterations, the human observers showed a preference for 5 iterations; however, only one of the variants of the CMO agreed with this selection. The others showed a preference for 15 iterations. We shall thus proceed to optimize the reconstruction parameters for even higher sensitivity collimators using this CMO, and then do the final comparison between collimators using their individually optimized parameters with human observers and three times the test images to reduce the statistical variation seen in our present results.

Konate, Souleymane; Pretorius, P. Hendrik; Gifford, Howard C.; O'Connor, J. Michael; Konik, Arda; Shazeeb, Mohammed Salman; King, Michael A.

2012-02-01

18

Neutron imaging camera  

NASA Astrophysics Data System (ADS)

The Neutron Imaging Camera (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, ~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 3He(n,p)3H interactions in the 3-DTI volume. The performance of the NIC from laboratory is presented.

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

2008-05-01

19

LROC Observations of Geologic Features in the Marius Hills  

NASA Astrophysics Data System (ADS)

Lunar volcanic cones, domes, and their associated geologic features are important objects of study for the LROC science team because they represent possible volcanic endmembers that may yield important insights into the history of lunar volcanism and are potential sources of lunar resources. Several hundred domes, cones, and associated volcanic features are currently targeted for high-resolution LROC Narrow Angle Camera [NAC] imagery[1]. The Marius Hills, located in Oceanus Procellarum (centered at ~13.4°N, -55.4°W), represent the largest concentration of these volcanic features on the Moon including sinuous rilles, volcanic cones, domes, and depressions [e.g., 2-7]. The Marius region is thus a high priority for future human lunar exploration, as signified by its inclusion in the Project Constellation list of notional future human lunar exploration sites [8], and will be an intense focus of interest for LROC science investigations. Previous studies of the Marius Hills have utilized telescopic, Lunar Orbiter, Apollo, and Clementine imagery to study the morphology and composition of the volcanic features in the region. Complementary LROC studies of the Marius region will focus on high-resolution NAC images of specific features for studies of morphology (including flow fronts, dome/cone structure, and possible layering) and topography (using stereo imagery). Preliminary studies of the new high-resolution images of the Marius Hills region reveal small-scale features in the sinuous rilles including possible outcrops of bedrock and lobate lava flows from the domes. The observed Marius Hills are characterized by rough surface textures, including the presence of large boulders at the summits (~3-5m diameter), which is consistent with the radar-derived conclusions of [9]. Future investigations will involve analysis of LROC stereo photoclinometric products and coordinating NAC images with the multispectral images collected by the LROC WAC, especially the ultraviolet data, to enable measurements of color variations within and amongst deposits and provide possible compositional insights, including the location of possibly related pyroclastic deposits. References: [1] J. D. Stopar et al. (2009), LRO Science Targeting Meeting, Abs. 6039 [2] Greeley R (1971) Moon, 3, 289-314 [3] Guest J. E. (1971) Geol. and Phys. of the Moon, p. 41-53. [4] McCauley J. F. (1967) USGS Geologic Atlas of the Moon, Sheet I-491 [5] Weitz C. M. and Head J. W. (1999) JGR, 104, 18933-18956 [6] Heather D. J. et al. (2003) JGR, doi:10.1029/2002JE001938 [7] Whitford-Stark, J. L., and J. W. Head (1977) Proc. LSC 8th, 2705-2724 [8] Gruener J. and Joosten B. K. (2009) LRO Science Targeting Meeting, Abs. 6036 [9] Campbell B. A. et al. (2009) JGR, doi:10.1029/2008JE003253.

Lawrence, S.; Stopar, J. D.; Hawke, R. B.; Denevi, B. W.; Robinson, M. S.; Giguere, T.; Jolliff, B. L.

2009-12-01

20

LRO Camera Imaging of Constellation Sites  

NASA Astrophysics Data System (ADS)

One of the top priorities for Lunar Reconnaissance Orbiter Camera (LROC) imaging during the "exploration" phase of the mission is thorough coverage of 50 sites selected to represent a wide variety of terrain types and geologic features that are of interest for human exploration. These sites, which are broadly distributed around the Moon and include locations at or near both poles, will provide the Constellation Program with data for a set of targets that represent a diversity of scientific and resource opportunities, thus forming a basis for planning for scientific exploration, resource development, and mission operations including traverse and habitation zone planning. Identification of the Constellation targets is not intended to be a site-selection activity. Sites include volcanic terrains (surfaces with young and old basalt flows, pyroclastic deposits, vents, fissures, domes, low shields, rilles, wrinkle ridges, and lava tubes), impact craters and basins (crater floors, central peaks, terraces and walls; impact-melt and ejecta deposits, basin ring structures; and antipodal terrain), and contacts of geologic features in areas of complex geology. Sites at the poles represent different lighting conditions and include craters with areas of permanent shadow. Sites were also chosen that represent typical feldspathic highlands terrain, areas in the highlands with anomalous compositions, and unusual features such as magnetic anomalies. These sites were reviewed by the Lunar Exploration Analysis Group (LEAG). These sites all have considerable scientific and exploration interest and were derived from previous studies of potential lunar landing sites, supplemented with areas that capitalize on discoveries from recent orbital missions. Each site consists of nested regions of interest (ROI), including 10×10 km, 20×20 km, and 40×40 km areas. Within the 10×10 and 20×20 ROIs, the goal is to compile a set of narrow-angle-camera (NAC) observations for a controlled mosaic, photometric and geometric stereo, and images taken at low and high sun to enhance morphology and albedo, respectively. These data will provide the basis for topographic maps, digital elevation models, and slope and boulder hazard maps that could be used to establish landing or habitation zones. Within the 40×40 ROIs, images will be taken to achieve the best possible high-resolution mosaics. All ROIs will have wide-angle-camera context images covering the sites and surrounding areas. At the time of writing (prior to the end of the LRO commissioning phase), over 500 individual NAC frames have been acquired for 47 of the 50 sites. Because of the polar orbit, the majority of repeat coverage occurs for the polar and high latitude sites. Analysis of the environment for several representative Constellation site ROIs will be presented.

Gruener, J.; Jolliff, B. L.; Lawrence, S.; Robinson, M. S.; Plescia, J. B.; Wiseman, S. M.; Li, R.; Archinal, B. A.; Howington-Kraus, A. E.

2009-12-01

21

Insights into Pyroclastic Volcanism on the Moon with LROC Data  

NASA Astrophysics Data System (ADS)

Lunar pyroclastic deposits are high-priority targets for the Lunar Reconnaissance Orbiter Camera. Images from the Narrow Angle Camera (NAC; 0.5 m/pixel) and Wide Angle Camera (WAC; 7 bands, 100 m/p visible, 400 m/p ultraviolet) are being acquired. Studies of pyroclastic deposits with LRO data have the potential to resolve major questions concerning their distribution, composition, volume, eruptive styles, and role in early lunar volcanism. Analyses of LROC Commissioning and early Exploration Phase data focus on preliminary assessment of morphology and compositional variation among lunar pyroclastic deposits. At sites such as Rima Bode, Sulpicius Gallus, Aristarchus plateau, and Humorum, Alphonsus and Oppenheimer craters, LROC data are being used to search for evidence that may allow us to identify separate eruptive episodes from the same vent, pulses of magma intrusions and/or crustal dikes, and possible changes in composition and volatility of source materials with time. Preliminary observations of NAC data for possible pyroclastic vents reveal typically smooth, dark surfaces with variations in surface texture, roughness, and apparent albedo that may be related to differences in eruption mechanism and/or duration. Evidence of layering at some sites suggest low-volume eruptions or multiple events. Further analyses of LROC data will allow identification of intra-deposit compositional variations, possible juvenile components, and evaluation of the distributions and relative amounts of juvenile vs. host-rock components. Combined NAC and WAC data also will enable us to characterize spatial extents, distributions, and compositions of pyroclastic deposits and relate them to other sampled glass types and possibly to their associated basalts. WAC color data will be used to characterize titanium contents of pyroclastic deposits, to map the diversity of effusive and pyroclastic units with variable titanium contents that are currently not recognized, and to identify which pyroclastic deposits are the best sources of titanium and associated volatile elements. Using NAC stereo data, meter-scale topographic models of the surface will allow us to better constrain emplacement and distribution of possible juvenile materials, the geometry of small pyroclastic eruptions, and models of their eruption.

Gaddis, L. R.; Robinson, M. S.; Hawke, B. R.; Giguere, T.; Gustafson, O.; Keszthelyi, L. P.; Lawrence, S.; Stopar, J.; Jolliff, B. L.; Bell, J. F.; Garry, W. B.

2009-12-01

22

Impact melt volume estimates in small-to-medium sized craters on the Moon from the Lunar Orbiter Laser Altimeter (LOLA) and Lunar Reconnaissance Orbiter Camera (LROC)  

NASA Astrophysics Data System (ADS)

Direct measurements of the volume of melt generated during cratering have only been possible using data acquired at terrestrial craters. These measurements are usually the result of areal mapping efforts, drill core investigations, and assessments of the amount of erosion a crater and its melt sheet might have undergone. Good data for melt volume are needed to further test and validate both analytical and numerical models of melt generation on terrestrial planets, whose results can vary by as much as a factor of 10 for identical impact conditions. Such models are used to provide estimates of the depth of origin of surface features (e.g., central peaks and rings) seen within craters and could influence the interpretations of their diameter-to-depth relationships. For example, high velocity impacts (>30km/s) on Mercury are expected to produce significant melt volumes, which could influence crater aspect ratio. The Lunar Reconnaissance Orbiter has now returned a wealth of new data, including those from small-to-medium sized fresh craters on the Moon (1kmLROC observations and LOLA altimetry (spatial sampling ~56m, vertical precision =10cm) are of such good quality that additional new melt volume estimates can be obtained for many of these craters. Using geological maps from the Apollo era, we have identified over 100 fresh crater candidates for investigation. Preliminary results indicate that melt volumes can vary significantly for given crater sizes, sometimes even exceeding estimates from current numerical and analytical models in the literature for impacts on the Moon. The broad range of observed melt volumes might be due to local variations in the target properties (including density, composition and porosity), projectile speeds and possibly projectile properties, the range of which the theoretical models do not typically consider.

Barnouin, O. S.; Seelos, K. D.; McGovern, A.; Denevi, B. W.; Zuber, M. T.; Smith, D. E.; Robinson, M. S.; Neumann, G. A.; Mazarico, E.; Torrence, M. H.

2010-12-01

23

Binarising Camera Images for OCR  

Microsoft Academic Search

In this paper we describe a new binarisation method de- signed specifically for OCR of low quality camera images: Background Surface Thresholding or BST. This method is robust to lighting variations and produces images with very little noise and consistent stroke width. BST computes a \\

Mauritius Seeger; Christopher R. Dance

2001-01-01

24

LROC WAC Ultraviolet Reflectance of the Moon  

NASA Astrophysics Data System (ADS)

Earth-based color filter photography, first acquired in the 1960s, showed color differences related to morphologic boundaries on the Moon [1]. These color units were interpreted to indicate compositional differences, thought to be the result of variations in titanium content [1]. Later it was shown that iron abundance (FeO) also plays a dominant role in controlling color in lunar soils [2]. Equally important is the maturity of a lunar soil in terms of its reflectance properties (albedo and color) [3]. Maturity is a measure of the state of alteration of surface materials due to sputtering and high velocity micrometeorite impacts over time [3]. The Clementine (CL) spacecraft provided the first global and digital visible through infrared observations of the Moon [4]. This pioneering dataset allowed significant advances in our understanding of compositional (FeO and TiO2) and maturation differences across the Moon [5,6]. Later, the Lunar Prospector (LP) gamma ray and neutron experiments provided the first global, albeit low resolution, elemental maps [7]. Newly acquired Moon Mineralogic Mapper hyperspectral measurements are now providing the means to better characterize mineralogic variations on a global scale [8]. Our knowledge of ultraviolet color differences between geologic units is limited to low resolution (km scale) nearside telescopic observations, and high resolution Hubble Space Telescope images of three small areas [9], and laboratory analyses of lunar materials [10,11]. These previous studies detailed color differences in the UV (100 to 400 nm) related to composition and physical state. HST UV (250 nm) and visible (502 nm) color differences were found to correlate with TiO2, and were relatively insensitive to maturity effects seen in visible ratios (CL) [9]. These two results led to the conclusion that improvements in TiO2 estimation accuracy over existing methods may be possible through a simple UV/visible ratio [9]. The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) provides the first global lunar ultraviolet through visible (321 nm to 689 nm) multispectral observations [12]. The WAC is a sevencolor push-frame imager with nominal resolutions of 400 m (321, 360 nm) and 100 m (415, 566, 604, 643, 689 nm). Due to its wide field-of-view (60° in color mode) the phase angle within a single line varies ±30°, thus requiring the derivation of a precise photometric characterization [13] before any interpretations of lunar reflectance properties can be made. The current WAC photometric correction relies on multiple WAC observations of the same area over a broad range of phase angles and typically results in relative corrections good to a few percent [13].

Robinson, M. S.; Denevi, B. W.; Sato, H.; Hapke, B. W.; Hawke, B. R.

2011-10-01

25

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

NASA Astrophysics Data System (ADS)

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).

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

2011-10-01

26

Full Stokes polarization imaging camera  

NASA Astrophysics Data System (ADS)

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.

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

2011-09-01

27

Marius Hills: Surface Roughness from LROC and Mini-RF  

NASA Astrophysics Data System (ADS)

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 blocks are between 9-12 m in diameter. These blocks are not associated with impact craters and have at most a thin layer of regolith. There is minimal visible evidence for downslope movement. Relatively high block abundances are also seen on the summits of steep-sided asymmetrical positive relief features (“cones”) atop low-sided domes. Digitization efforts will continue as we study the block populations of different geologic features in the Marius Hills region and correlate the results with Mini-RF data, which will provide new information about the emplacement of volcanic features in the region. [1] J.D. Stopar et al., LPI Contribution 1483 (2009) 93-94. [2] S.J. Lawrence et al. (2010) LPSC 41 #1906. [2] S.J. Lawrence et al. (2010) LPSC 41 # 2689. [3] C. Coombs & B.R. Hawke (1992) 2nd Proc. Lun. Bases & Space Act. 21st Cent pp. 219-229. [4]J.Gruener and B. Joosten (2009) LPI Contributions 1483 50-51. [5] D.B.J. Bussey et al. (2010) LPSC 41 # 2319. [6] B.A. Campbell et al. (2009) JGR-Planets, 114, 01001. [7] S.W. Anderson et al. (1998) GSA Bull, 110, 1258-1267.

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

2010-12-01

28

LROC and Other Remote Sensing Studies of Pyroclastic Deposits in the Mare Humorum Region  

NASA Astrophysics Data System (ADS)

The two large regional pyroclastic deposits are dominated by pyroclastic glasses. LROC NAC images show that the thickest portion of the SWH deposit is dark, flat, smooth, and deficient in blocks >1m across.

Hawke, B. R.; Giguere, T. A.; Lawrence, S. J.; Campbell, B. A.; Gaddis, L. R.; Gustafson, J. O.; Hagerty, J. J.; Peterson, C. A.; Robinson, M. S.; Lroc Team

2010-03-01

29

Intelligent thermal imaging camera with network interface  

NASA Astrophysics Data System (ADS)

In recent years, a significant increase in usage of thermal imagining cameras can be observed in both public and commercial sector, due to the lower cost and expanding availability of uncooled microbolometer infrared radiation detectors. Devices present on the market vary in their parameters and output interfaces. However, all these thermographic cameras are only a source of an image, which is then analyzed in external image processing unit. There is no possibility to run users dedicated image processing algorithms by thermal imaging camera itself. This paper presents a concept of realization, architecture and hardware implementation of "Intelligent thermal imaging camera with network interface" utilizing modern technologies, standards and approach in one single device.

Sielewicz, Krzysztof M.; Kasprowicz, Grzegorz; Po?niak, Krzysztof T.; Romaniuk, R. S.

2011-06-01

30

Morphology and Composition of Localized Lunar Dark Mantle Deposits With LROC Data  

NASA Astrophysics Data System (ADS)

Clementine color (ultraviolet, visible or UVVIS) and Lunar Reconnaissance Orbiter (LRO) Wide Angle (WAC) and Narrow Angle (NAC) camera data provide the means to investigate localized lunar dark-mantle deposits (DMDs) of potential pyroclastic origin. Our goals are to (1) examine the morphology and physical characteristics of these deposits with LROC WAC and NAC data; (2) extend methods used in earlier studies of lunar DMDs with Clementine spectral reflectance (CSR) data; (3) use LRO WAC multispectral data to complement and extend the CSR data for compositional analyses; and (4) apply these results to identify the likely mode of emplacement and study the diversity of compositions among these deposits. Pyroclastic deposits have been recognized all across the Moon, identified by their low albedo, smooth texture, and mantling relationship to underlying features. Gaddis et al. (2003) presented a compositional analysis of 75 potential lunar pyroclastic deposits (LPDs) based on CSR measurements. New LRO camera (LROC) data permit more extensive analyses of such deposits than previously possible. Our study began with six sites on the southeastern limb of the Moon that contain nine of the cataloged 75 potential pyroclastic deposits: Humboldt (4 deposits), Petavius, Barnard, Abel B, Abel C, and Titius. Our analysis found that some of the DMDs exhibit qualities characteristic of fluid emplacement, such as flat surfaces, sharp margins, embaying relationships, and flow textures. We conclude that the localized DMDs are a complex class of features, many of which may have formed by a combination of effusive and pyroclastic emplacement mechanisms. We have extended this analysis to include additional localized DMDs from the catalog of 75 potential pyroclastic deposits. We have examined high resolution (up to 0.5 m/p) NAC images as they become available to assess the mode of emplacement of the deposits, locate potential volcanic vents, and assess physical characteristics of the DMDs such as thickness, roughness, and rock abundance. Within and around each DMD, the Clementine UVVIS multispectral mosaic (100 m/p, 5 bands at 415, 750, 900, 950, and 1000 nm) and LROC WAC multispectral image cubes (75 to 400 m/p, 7 bands at 320, 360, 415, 565, 605, 645, and 690 nm) have been used to extract spectral reflectance data. Spectral ratio plots were prepared to compare deposits and draw conclusions regarding compositional differences, such as mafic mineral or titanium content and distribution, both within and between DMDs. The result of the study will be an improved classification of these deposits in terms of emplacement mechanisms and composition, including identifying compositional affinities among DMDs and between DMDs and other volcanic deposits.

Gustafson, O.; Bell, J. F.; Gaddis, L. R.; Hawke, B. R.; Robinson, M. S.; LROC Science Team

2010-12-01

31

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

NASA Astrophysics Data System (ADS)

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. We will show examples of LROC data including those for Constellation sites on the SPA rim and interior, a site between Bose and Alder Craters, sites east of Bhabha Crater, and sites on and near the “Mafic Mound” [see Pieters et al., this conference]. Together the LROC data and complementary products provide essential information for ensuring identification of safe landing and sampling sites within SPA basin that has never before been available for a planetary mission.

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

32

Digital image processing of metric camera imagery  

Microsoft Academic Search

The use of digitized Spacelab metric camera imagery for map updating is demonstrated for an area of Germany featuring agricultural and industrial areas, and a region of the White Nile. LANDSAT and Spacelab images were combined, and digital image processing techniques used for image enhancement. Updating was achieved by semiautomatic techniques, but for many applications manual editing may be feasible.

P. Lohmann

1985-01-01

33

Development of gamma ray imaging cameras  

NASA Astrophysics Data System (ADS)

In January 1990, the Department of Energy initiated this project with the objective to develop the technology for general purpose, portable gamma ray imaging cameras useful to the nuclear industry. The ultimate goal of this R&D initiative is to develop the analog to the color television camera where the camera would respond to gamma rays instead of visible photons. The two-dimensional real-time image would be displayed and indicate the geometric location of the radiation relative to the camera's orientation, while the brightness and 'color' would indicate the intensity and energy of the radiation and, hence, identify the emitting isotope. There is a strong motivation for developing such a device for applications within the nuclear industry, for both high- and low-level waste repositories, for environmental restoration problems, and for space and fusion applications. At present, there are no general purpose radiation cameras capable of producing spectral images for such practical applications. At the time of this writing, work on this project has been underway for almost 18 months. Substantial progress has been made in the project's two primary areas: mechanically-collimated (MCC) and electronically-collimated camera (ECC) designs. We present developments covering the mechanically-collimated design, and then discuss the efforts on the electronically-collimated camera. The renewal proposal addresses the continuing R&D efforts for the third year effort.

Wehe, D. K.; Knoll, G. F.

1992-05-01

34

Development of gamma ray imaging cameras  

SciTech Connect

In January 1990, the Department of Energy initiated this project with the objective to develop the technology for general purpose, portable gamma ray imaging cameras useful to the nuclear industry. The ultimate goal of this R D initiative is to develop the analog to the color television camera where the camera would respond to gamma rays instead of visible photons. The two-dimensional real-time image would be displayed would indicate the geometric location of the radiation relative to the camera's orientation, while the brightness and color'' would indicate the intensity and energy of the radiation (and hence identify the emitting isotope). There is a strong motivation for developing such a device for applications within the nuclear industry, for both high- and low-level waste repositories, for environmental restoration problems, and for space and fusion applications. At present, there are no general purpose radiation cameras capable of producing spectral images for such practical applications. At the time of this writing, work on this project has been underway for almost 18 months. Substantial progress has been made in the project's two primary areas: mechanically-collimated (MCC) and electronically-collimated camera (ECC) designs. We present developments covering the mechanically-collimated design, and then discuss the efforts on the electronically-collimated camera. The renewal proposal addresses the continuing R D efforts for the third year effort. 8 refs.

Wehe, D.K.; Knoll, G.F.

1992-05-28

35

Ultrasound Image Transmission via Camera Phones  

Microsoft Academic Search

Ultrasound is a modern imaging technique, which delivers no radiation and does not require injection of any chemicals to enhance\\u000a visualization. Unlike other imaging modalities, it can reach locations that are inaccessible to plain X-rays, computed tomography,\\u000a and magnetic resonance imaging. Ultrasound image transmission through camera phones can be useful in scenarios like remote\\u000a locations, disaster scenes, battlefields, cruise ships,

Michael Blaivas

36

Classroom multispectral imaging using inexpensive digital cameras.  

NASA Astrophysics Data System (ADS)

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.

Fortes, A. D.

2007-12-01

37

Development of CCD Imaging Block for Single Chip Color Camera  

Microsoft Academic Search

In recent years, the home use portable color camera and the camera recorder (VTR equipped with camera) market is getting larger. This kind of camera requires to be more compact and light-weighted, and to have a higher quality picture. CCD Image Sensor allows the camera to be small-sized and light-weighted, providing many advantages, such as low image lag, low image

Yoshiteru Ogawa; Yasuo Nakada; Hiromichi Yasui; Shigeyuki Ochi

1985-01-01

38

Simulating images captured by superposition lens cameras  

Microsoft Academic Search

As the demand for reduction in the thickness of cameras rises, so too does the interest in thinner lens designs. One such radical approach toward developing a thin lens is obtained from nature's superposition principle as used in the eyes of many insects. But generally the images obtained from those lenses are fuzzy, and require reconstruction algorithms to complete the

Ashok Samraj Thangarajan; Ramakrishna Kakarala

2011-01-01

39

Color image processing in Canon's digital camera  

Microsoft Academic Search

A new TTL white balance method is studied to get a good white balance for a wide variety of illumination in digital camera system. Parameters of white balance are decided only by analyzing a single shot of images in this method. A locus of a white point under various illumination is plotted in a certain 2D color space, and the

Yoshiro Udagawa

1996-01-01

40

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...

41

A non-intuitive aspect of Swensson's LROC model  

NASA Astrophysics Data System (ADS)

If the locations of abnormalities (targets) in an image are unknown, the evaluation of human observers' detection performance can be complex. Richard Swensson in 1996 developed a model that unified the various analysis approaches to this problem. For the LROC experiment, the model assumed that a false-positive report-arises from the latent decision variable of the most suspicious non-target location of the target stimuli. The localization scoring was based on the same latent decision variable, i.e., when the latent decision variable at the non-target location was greater than latent decision variable at the target location the response was scored as a miss. Human observer reports vary, i.e., different locations have been identified during replications. A Monte Carlo model was developed to investigate this variation and identified a non-intuitive aspect of Swensson's LROC model. When the number of potentially suspicious locations was 1, the model performance was greater than apparently possible. For example, assume that target expected latent decision variable is 1.0. Both target and non-target standard deviations were assumed to be 1.0. The model predicts the area-under-the-ROC is 0.815, which implies da=1.27. If the target latent decision variable was 0.0, then da=0.61. The reason was the number latent decision variables in the model for the non-target stimuli is one, while the number latent decision variables for the target stimuli is the maximum of 2. The simulation indicated that the parameters of a LROC fit, when the number of suspicious locations is small or the observer performance is low, does not have the same intuitive meaning as ROC parameters of a SKE task.

Judy, Philip F.

2007-03-01

42

Preprocessing of a Fingerprint Image Captured with a Mobile Camera  

Microsoft Academic Search

Abstract— In this paper, we introduce the recognition of finger- print images captured with a mobile camera. The corresponding image preprocessing algorithms are also discussed. Some char- acteristics of fingerprint images captured with mobile cameras are quite different from those obtained by conventional touch- based sensors. For example, mobile camera images are colored while conventional touch-based sensors produce only black

Chulhan Lee; Sanghoon Lee; Jaihie Kim; Sung-jae Kim

2006-01-01

43

Imaging of gamma emitters using scintillation cameras  

NASA Astrophysics Data System (ADS)

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.

Ricard, Marcel

2004-07-01

44

Speckle Camera Imaging of the Planet Pluto  

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

45

High-Speed Camera for Frequency Domain Imaging  

Microsoft Academic Search

We describe a high-speed camera system for performing frequency domain imaging with applications to photon migration imaging or fluorescence lifetime imaging. Field programmable gate arrays allow processing images up to 2 gigapixels per second.

Abneesh Srivastava; David Watt; Gregory W. Faris

2007-01-01

46

Cervical SPECT Camera for Parathyroid Imaging  

SciTech Connect

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.

None

2012-08-31

47

New insight into lunar impact melt mobility from the LRO camera  

USGS Publications Warehouse

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.

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

48

New insight into lunar impact melt mobility from the LRO camera  

NASA Astrophysics Data System (ADS)

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.

Bray, V. J.; Tornabene, L. L.; Keszthelyi, L. P.; McEwen, A. S.; Hawke, B. R.; Giguere, T. A.; Kattenhorn, S. A.; Garry, W. B.; Rizk, B.; Caudill, C. M.; Gaddis, L. R.; van der Bogert, C. H.

2010-11-01

49

Methods for identification of images acquired with digital cameras  

NASA Astrophysics Data System (ADS)

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.

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

2001-02-01

50

GLD100 - Lunar topography from LROC WAC stereo  

NASA Astrophysics Data System (ADS)

The LROC WAC instrument of the LRO mission comprises substantial stereo image data from adjacent orbits. Multiple coverage of the entire surface of the Moon at a mean ground scale of 75 m/pxl has already been achieved within the first two years of the mission. We applied photogrammetric stereo processing methods for the derivation of a 100 m raster DTM (digital terrain model), called GLD100, from several tens of thousands stereo models. The GLD100 covers the lunar surface between 80° northern and southern latitude. Polar regions are excluded because of poor illumination and stereo conditions. Vertical differences of the GLD100 to altimetry data from the LRO LOLA instrument are small, the mean deviation is typically about 20 m, without systematic lateral or vertical offsets.

Scholten, F.; Oberst, J.; Robinson, M. S.

2011-10-01

51

The European Photon Imaging Camera on XMM-Newton: The MOS cameras : The MOS cameras  

NASA Astrophysics Data System (ADS)

The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain seven MOS CCDs, while the third uses twelve PN CCDs, defining a circular field of view of 30' diameter in each case. The CCDs were specially developed for EPIC, and combine high quality imaging with spectral resolution close to the Fano limit. A filter wheel carrying three kinds of X-ray transparent light blocking filter, a fully closed, and a fully open position, is fitted to each EPIC instrument. The CCDs are cooled passively and are under full closed loop thermal control. A radio-active source is fitted for internal calibration. Data are processed on-board to save telemetry by removing cosmic ray tracks, and generating X-ray event files; a variety of different instrument modes are available to increase the dynamic range of the instrument and to enable fast timing. The instruments were calibrated using laboratory X-ray beams, and synchrotron generated monochromatic X-ray beams before launch; in-orbit calibration makes use of a variety of celestial X-ray targets. The current calibration is better than 10% over the entire energy range of 0.2 to 10 keV. All three instruments survived launch and are performing nominally in orbit. In particular full field-of-view coverage is available, all electronic modes work, and the energy resolution is close to pre-launch values. Radiation damage is well within pre-launch predictions and does not yet impact on the energy resolution. The scientific results from EPIC amply fulfil pre-launch expectations.

Turner, M. J. L.; Abbey, A.; Arnaud, M.; Balasini, M.; Barbera, M.; Belsole, E.; Bennie, P. J.; Bernard, J. P.; Bignami, G. F.; Boer, M.; Briel, U.; Butler, I.; Cara, C.; Chabaud, C.; Cole, R.; Collura, A.; Conte, M.; Cros, A.; Denby, M.; Dhez, P.; Di Coco, G.; Dowson, J.; Ferrando, P.; Ghizzardi, S.; Gianotti, F.; Goodall, C. V.; Gretton, L.; Griffiths, R. G.; Hainaut, O.; Hochedez, J. F.; Holland, A. D.; Jourdain, E.; Kendziorra, E.; Lagostina, A.; Laine, R.; La Palombara, N.; Lortholary, M.; Lumb, D.; Marty, P.; Molendi, S.; Pigot, C.; Poindron, E.; Pounds, K. A.; Reeves, J. N.; Reppin, C.; Rothenflug, R.; Salvetat, P.; Sauvageot, J. L.; Schmitt, D.; Sembay, S.; Short, A. D. T.; Spragg, J.; Stephen, J.; Strüder, L.; Tiengo, A.; Trifoglio, M.; Trümper, J.; Vercellone, S.; Vigroux, L.; Villa, G.; Ward, M. J.; Whitehead, S.; Zonca, E.

2001-01-01

52

Establishing imaging sensor specifications for digital still cameras  

Microsoft Academic Search

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

Michael A. Kriss

2007-01-01

53

A Survey on Digital Camera Image Forensic Methods  

Microsoft Academic Search

There are two main interests in Digital Camera Image Forensics, namely source identification and forgery detection. In this paper, we first briefly provide an introduction to the major processing stages inside a digital camera and then review several methods for source digital camera identification and forgery detection. Existing methods for source identification explore the various processing stages inside a digital

Tran Van Lanh; Kai-sen Chong; Sabu Emmanuel; Mohan S. Kankanhalli

2007-01-01

54

Rapid Optimization of SPECT Scatter Correction Using Model LROC Observers  

PubMed Central

The problem we address is the optimization and comparison of window-based scatter correction (SC) methods in SPECT for maximum a posteriori reconstructions. While sophisticated reconstruction-based SC methods are available, the commonly used window-based SC methods are fast, easy to use, and perform reasonably well. Rather than subtracting a scatter estimate from the measured sinogram and then reconstructing, we use an ensemble approach and model the mean scatter sinogram in the likelihood function. This mean scatter sinogram estimate, computed from satellite window data, is itself inexact (noisy). Therefore two sources of noise, that due to Poisson noise of unscattered photons and that due to the model error in the scatter estimate, are propagated into the reconstruction. The optimization and comparison is driven by a figure of merit, the area under the LROC curve (ALROC) that gauges performance in a signal detection plus localization task. We use model observers to perform the task. This usually entails laborious generation of many sample reconstructions, but in this work, we instead develop a theoretical approach that allows one to rapidly compute ALROC given known information about the imaging system and the scatter correction scheme. A critical step in the theory approach is to predict additional (above that due to to the propagated Poisson noise of the primary photons) contributions to the reconstructed image covariance due to scatter (model error) noise. Simulations show that our theory method yields, for a range of search tolerances, LROC curves and ALROC values in close agreement to that obtained using model observer responses obtained from sample reconstruction methods. This opens the door to rapid comparison of different window-based SC methods and to optimizing the parameters (including window placement and size, scatter sinogram smoothing kernel) of the SC method.

Kulkarni, Santosh; Khurd, Parmeshwar; Zhou, Lili; Gindi, Gene

2010-01-01

55

Simulating images captured by superposition lens cameras  

NASA Astrophysics Data System (ADS)

As the demand for reduction in the thickness of cameras rises, so too does the interest in thinner lens designs. One such radical approach toward developing a thin lens is obtained from nature's superposition principle as used in the eyes of many insects. But generally the images obtained from those lenses are fuzzy, and require reconstruction algorithms to complete the imaging process. A hurdle to developing such algorithms is that the existing literature does not provide realistic test images, aside from using commercial ray-tracing software which is costly. A solution for that problem is presented in this paper. Here a Gabor Super Lens (GSL), which is based on the superposition principle, is simulated using the public-domain ray-tracing software POV-Ray. The image obtained is of a grating surface as viewed through an actual GSL, which can be used to test reconstruction algorithms. The large computational time in rendering such images requires further optimization, and methods to do so are discussed.

Thangarajan, Ashok Samraj; Kakarala, Ramakrishna

2011-02-01

56

Measurement of the nonuniformity of first responder thermal imaging cameras  

Microsoft Academic Search

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 the nonuniformity of thermal imaging cameras. Several commercially available

Andrew Lock; Francine Amon

2008-01-01

57

2000-fps digital imager for replacing 16-mm film cameras  

NASA Astrophysics Data System (ADS)

For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne weapon testing, range tracking, and other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost-effective solution. Film-based cameras still produce the best resolving capability. However, film development time, chemical disposal, non-optimal lighting conditions, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new imager from Kodak that has been designed to replace 16 mm high-speed film cameras. Also included is a detailed configuration, operational scenario, and cost analysis of Kodak's imager for airborne applications. The KODAK EKTAPRO HG Imager, Model 2000 is a high-resolution color or monochrome CCD Camera especially designed for replacement of rugged high-speed film cameras. The HG Imager is a self-contained camera. It features a high-resolution [512 X 384], light-sensitive CCD sensor with an electronic shutter. This shutter provides blooming protection that prevents 'smearing' of bright light sources, e.g., camera looking into a bright sun reflection. The HG Imager is a very rugged camera packaged in a highly integrated housing. This imager operates from +22 to 42 VDC. The HG Imager has a similar interface and form factor as that of high-speed film cameras, e.g., Photosonics 1B. However, the HG also has the digital interfaces such as 100-Base-T Ethernet and RS-485 that enable control and image transfer. The HG Imager is designed to replace 16 mm film cameras that support rugged testing applications.

Balch, Kris S.

1999-06-01

58

Image responses to x-ray radiation in ICCD camera  

NASA Astrophysics Data System (ADS)

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.

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

2013-08-01

59

Fast Camera Imaging of Hall Thruster Ignition  

SciTech Connect

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 ?s. The cathode introduces azimuthal asymmetry, which persists for about 30 ?s 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

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

2011-02-24

60

Image Alignment for Multiple Camera High Dynamic Range Microscopy.  

PubMed

This paper investigates the problem of image alignment for multiple camera high dynamic range (HDR) imaging. HDR imaging combines information from images taken with different exposure settings. Combining information from multiple cameras requires an alignment process that is robust to the intensity differences in the images. HDR applications that use a limited number of component images require an alignment technique that is robust to large exposure differences. We evaluate the suitability for HDR alignment of three exposure-robust techniques. We conclude that image alignment based on matching feature descriptors extracted from radiant power images from calibrated cameras yields the most accurate and robust solution. We demonstrate the use of this alignment technique in a high dynamic range video microscope that enables live specimen imaging with a greater level of detail than can be captured with a single camera. PMID:22545028

Eastwood, Brian S; Childs, Elisabeth C

2012-01-01

61

CCD CAMERA CALIBRATION BASED ON THE SUN'S IMAGES  

Microsoft Academic Search

A Nikon D70s Digital camera with resolution of 6M, equipped with a narrow angle Nikkor 85 mm f\\/1.8D lens and suitable filters; was calibrated successfully, by two sets of the sun's images. Each set was taken while the camera's orientation was held unchanged for more than a hour. During this time the sun's image cross the camera's field of view

U. Ethrog

2006-01-01

62

Low cost millimetre wave camera imaging up to 140GHz  

Microsoft Academic Search

A millimetre wave (nun-wave) camera that combines a novel mechanical scanning method with a sparse array of receivers has been demonstrated. The camera provides frequency independent, near real-time raster images with high efficiency and can be used with either active illumination or in a passive mode. Working with 77GH2, 94GHz and 140GHz receivers, the camera has provided high-quality, fast-capture images.

R. Doyle; B. Lyons; J. Walshe; P. Curtin; A. H. Lettington; T. McEnroe; J. McNaboe

2004-01-01

63

Determining the Camera Response from Images: What Is Knowable?  

Microsoft Academic Search

An image acquired by a camera consists of measured intensity values which are related to scene radiance by a function called the camera response function. Knowledge of this response is necessary for computer vision algorithms which depend on scene radiance. One way the response has been determined is by establishing a mapping of intensity values between images taken with different

Michael D. Grossberg; Shree K. Nayar

2003-01-01

64

Factors affecting the accuracy of thermal imaging cameras in volcanology  

Microsoft Academic Search

Volcano observatories and researchers are recognizing the potential usefulness of thermal imaging cameras both before and during volcanic eruptions. Obvious applications include measurements of the surface temperatures of active lava domes and lava flows to determine the location of the most active parts of these potentially hazardous features. If appropriate precautions are taken, the new generation of thermal imaging cameras

M. Ball; H. Pinkerton

2006-01-01

65

Camera system for autostereoscopic display using floating real image  

NASA Astrophysics Data System (ADS)

The present paper proposes a 3D camera system for teleoperation using autostereoscopic display based on floating real image. To present the operator 3-D images which correspond to his viewpoint, the image has to be updated in accordance with the motion of the operator's head. The proposed method combines camera motion control, which keeps on taking the proper texture for the viewpoint, and the image transformation software, which copes with the fast motion of the viewer the camera motion cannot follow. With this technology, presentation of robust 3-D image is realized.

Matsuda, Isamu; Kakeya, Hideki

2004-05-01

66

Relative orientation of videos from range imaging cameras  

NASA Astrophysics Data System (ADS)

In this paper we investigate the determination of camera relative orientation in videos from time of flight (ToF) range imaging camera. The task of estimating the relative orientation is realized by fusion of range flow and optical flow constraints, which integrates the range and the intensity channels in a single framework. We demonstrate our approach on videos from a ToF camera involving camera translation and rotational motion and compare it with the ground truth data. Furthermore we distinguish camera motion from an independently moving object using a robust adjustment.

Ghuffar, Sajid; Ressl, Camillo; Pfeifer, Norbert

2013-04-01

67

Imaging Characteristics of Three Cameras Using the Scheimpflug Principle  

Microsoft Academic Search

We studied the handling and the potentials of three different cameras operating according to the Scheimpflug principle and which currently are commercially available. The examinations were performed with the cameras Topcon SL-45, Topcon SL-6E with cataract attachment and Zeiss SLC system. Pigmented Brown-Norway rats with ultraviolet-B-induced cataract were used as the examination model. The image characteristics of the three cameras

Masami Kojima; Alfred Wegener; Otto Hockwin

1990-01-01

68

TWICE-IMAGING AIRBORNE CAMERA SYSTEM WITH DISTRIBUTED SENSORS  

Microsoft Academic Search

Digital airborne cameras play a significant role for aerial Photogramm etry development from analog to full-digital age. Because of the gap between digital sensor performance and Photogrammetry request, digital airborne also becomes the bottleneck of full-digital approach. In this paper, we present a design of twice-imaging airborne camera system with distributed sensors based on film camera, and carry out optical

S. H. Zhao; L. Yanb; X. H. Duan; Y. K. Wu; T. T. Shen; M. D. Su

69

Mars Imaging Camera (MIC) on board PLANET-B  

Microsoft Academic Search

Mars Imaging Camera (MIC) on board PLANET-B, Japanese Mars mission, is a small, compact and lightweight imager. It features three-color linear CCD aligned with the spacecraft's spin axis and is designed to take two-dimensional images of Mars and its satellites using the spacecraft's spin.The total field of view (FOV) of the camera is 360 degree (around the spin axis) ×

Keiken Ninomiya; Tatsuaki Hashimoto; Akikom Nakamura; Tadashi Mukai; Masato Nakamura; Masahiro Ogasawara; Naoki Yoshizawa; Juro Ishida; Yasuhiko Mizushima; Hiroto Hosoda; Masayo Takano

1999-01-01

70

Ultrafast x-ray imaging with sliced sampling streak cameras  

SciTech Connect

The ultrafast imaging methods in sliced sampling streak cameras are investigated. It is shown that the sampling-image x-ray streak camera has potential advantages in highly time-resolved and space-resolved imaging for imploded core plasmas. An optimized sampling method is presented to acquire two-dimensional spatial resolutions {<=}10 {mu}m and temporal resolution {approx}10 ps, within a field of view {approx}100 {mu}m and a time range {approx}100 ps.

Huang, T.X.; Nakai, M.; Shiraga, H.; Azechi, H.; Huang, T.X.; Ding, Y.K.; Zheng, Z.J. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Research Center of Laser Fusion, Mianyang 621900 (China)

2006-02-15

71

Imaging camera of spectrum-UV: a status report  

Microsoft Academic Search

The status of the imaging camera for the spectrum UV space telescope (a 170 cm UV telescope to be built by the space agencies of Canada, Germany, Italy, Russia and Ukraina) is briefly reported. The concept of this camera is to have a double focal length choice on the same detector. This is accomplished via a single flat mirror for

Andrea Baruffolo; Riccardo U. Claudi; R. Falomo; Roberto Ragazzoni

1994-01-01

72

An Easy Camera Pose Method from Fisheye Image  

Microsoft Academic Search

We present an easy technique to estimate fisheye camera pose using two vertical lines and one horizontal line on a space plane under a single fisheye view in this paper. If fisheye camera is calibrated, fisheye image points should be mapped on the unit sphere, we may first fit two vertical projected planes and one horizontal projected plane from fisheye

Haijiang Zhu; Shigang Li

2009-01-01

73

Imaging Emission Spectra with Handheld and Cellphone Cameras  

ERIC Educational Resources Information Center

|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…

Sitar, David

2012-01-01

74

Imaging Emission Spectra with Handheld and Cellphone Cameras  

ERIC Educational Resources Information Center

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…

Sitar, David

2012-01-01

75

Extraction of cloud statistics from whole sky imaging cameras  

SciTech Connect

Computer codes have been developed to extract basic cloud statistics from whole sky imaging (WSI) cameras. This report documents, on an algorithmic level, the steps and processes underlying these codes. Appendices comment on code details and on how to adapt to future changes in either the source camera or the host computer.

Kegelmeyer, W.P. Jr.

1994-03-01

76

Imaging Emission Spectra with Handheld and Cellphone Cameras  

NASA Astrophysics Data System (ADS)

As point-and-shoot digital camera technology advances it is becoming easier to image spectra in a laboralory setting on a shoestring budget and get immediale 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 point-and-shoot auto focusing camera and two different cellphone cameras: one at 6.1 MP and the other at 5.1 MP.

Sitar, David

2012-12-01

77

Recording Images Using a Simple Pinhole Camera  

NSDL National Science Digital Library

In this lesson, students develop and expand their observational skills and technological understanding by building and operating a pinhole camera. The interdisciplinary connections are in the realm of application in this motivating activity. The lesson pr

Eichinger, John

2009-05-30

78

Camera Image Synchronisation in Multiple Camera Real-Time 3D Reconstruction of Moving Humans  

Microsoft Academic Search

We present an analysis of the requirement for input synchronisation in a multi-camera 3D reconstruction system for real-time applications such as telepresence. Synchro- nisation of the cameras at the acquisition stage is universally used to ensure the images feeding the reconstruction algorithm were taken at the same time. However, this requirement adds delays to the reconstruction pipeline, therefore increasing the

Tobias Duckworth; David J. Roberts

2011-01-01

79

Extraction of cloud statistics from whole sky imaging cameras.  

National Technical Information Service (NTIS)

Computer codes have been developed to extract basic cloud statistics from whole sky imaging (WSI) cameras. This report documents, on an algorithmic level, the steps and processes underlying these codes. Appendices comment on code details and on how to ada...

W. P. Kegelmeyer

1994-01-01

80

Modal-Based Camera Correction for Large Pitch Stereo Imaging  

Microsoft Academic Search

\\u000a Stereo imaging is typically performed using two cameras that have been calibrated to account for lens-induced distortion and\\u000a pointing errors, resulting in rectified images that are processed to obtain distance information. The accuracy of a 3-D map\\u000a obtained from stereopsis is closely tied to the calibration data, and so relative motion between the cameras must be kept\\u000a small. In order

Prather Lanier; Nathan Short; Kevin Kochersberger; Lynn Abbott

81

Progress in Camera-Based Document Image Analysis  

Microsoft Academic Search

The increasing availability of high performance, low priced, portable digital imaging devices has created a tremendous opportunity for supplementing traditional scanning for document image acquisition. Digital cameras attached to cellular phones, PDAs, or as standalone still or video devices are highly mobile and easy to use; they can capture images of any kind of document including very thick books, historical

David S. Doermann; Jian Liang; Huiping Li

2003-01-01

82

Imaging Colorimetry Using a Digital Camera  

Microsoft Academic Search

In this work, we investigate the use of a digital camera for colorimetry. Our system consists of a measurement device and a corresponding calibration mapping. The goal is to design a system that will accurately assess the color of a sample. We develop two colorimetry systems by applying model-based and regression-based techniques. For both systems, the measurement device is formed

Wencheng Wu; Jan P. Allebach; Mostafa Analoui

1999-01-01

83

The WEBERSAT camera - An inexpensive earth imaging system  

NASA Astrophysics Data System (ADS)

WEBERSAT is a 27 pound LEO satellite launched in 1990 into a 500 mile polar orbit. One of its payloads is a low cost CCD color camera system developed by engineering students at Weber State University. The camera is a modified Canon CI-10 with a 25 mm lens, automatic iris, and 780 x 490 pixel resolution. The iris range control potentiometer was made programmable; a 10.7 MHz digitization clock, fixed focus support, and solid tantalum capacitors were added. Camera output signals, composite video, red, green, blue, and the digitization clock are fed to a flash digitizer, where they are processed for storage in RAM. Camera control commands are stored and executed via the onboard computer. The CCD camera has successfully imaged meteorological features of the earth, land masses, and a number of astronomical objects.

Jackson, Stephen; Raetzke, Jeffrey

84

Multiple range imaging camera operation with minimal performance impact  

NASA Astrophysics Data System (ADS)

Time-of-flight range imaging cameras operate by illuminating a scene with amplitude modulated light and measuring the phase shift of the modulation envelope between the emitted and reflected light. Object distance can then be calculated from this phase measurement. This approach does not work in multiple camera environments as the measured phase is corrupted by the illumination from other cameras. To minimize inaccuracies in multiple camera environments, replacing the traditional cyclic modulation with pseudo-noise amplitude modulation has been previously demonstrated. However, this technique effectively reduced the modulation frequency, therefore decreasing the distance measurement precision (which has a proportional relationship with the modulation frequency). A new modulation scheme using maximum length pseudo-random sequences binary phase encoded onto the existing cyclic amplitude modulation, is presented. The effective modulation frequency therefore remains unchanged, providing range measurements with high precision. The effectiveness of the new modulation scheme was verified using a custom time-of-flight camera based on the PMD19-K2 range imaging sensor. The new pseudo-noise modulation has no significant performance decrease in a single camera environment. In a two camera environment, the precision is only reduced by the increased photon shot noise from the second illumination source.

Whyte, Refael Z.; Payne, Andrew D.; Dorrington, Adrian A.; Cree, Michael J.

2010-02-01

85

Multiview: a novel multispectral IR imaging camera  

Microsoft Academic Search

The Surveillance Sciences Directorate of the Northrop Grumman Advanced Systems and Technology organization is developing a novel Multispectral IR camera known as Multiview. This prototype system is capable of simultaneously acquiring 4-color SWIR\\/MWIR 2D imagery that is both spatially and temporally registered utilizing a single 2562 HgCdTe snapshot IR FPA capable of frame rates in excess of 240 Hz. The

Michael A. Soel; Stanley Rudman; Robert Ryan; Nils J. Fonneland; Steve Milano

1997-01-01

86

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...

87

Spectral Imaging with a CID Camera.  

National Technical Information Service (NTIS)

This report describes a program of spectral imaging observations of the solar atmosphere using the Sacromento Peak Vacuum Tower Telescope. The observations were obtained with Lockheed instruments including: an active tilt mirror for image motion compensat...

T. D. Tarbell

1985-01-01

88

Laser speckle imaging using a consumer-grade color camera.  

PubMed

Laser speckle imaging (LSI) is a noninvasive optical imaging technique able to provide wide-field two-dimensional maps of moving particles. Raw laser speckle images are typically taken with a scientific-grade monochrome camera. We demonstrate that a digital single-lens reflex (dSLR) camera with a Bayer filter is able to provide similar sensitivity despite taking information only from a specific pixel color. Here we demonstrate the effect of changing three primary dSLR exposure settings (i.e., aperture, exposure time/shutter speed, and gain/sensitivity (ISO)) on speckle contrast. In addition, we present data from an in vivo reactive hyperemia experiment that demonstrates the qualitative similarity in blood-flow dynamics visualized with a color dSLR and a scientific-grade monochrome camera. PMID:23027244

Yang, Owen; Choi, Bernard

2012-10-01

89

Mars Global Surveyor Mars Orbiter Camera Image Gallery  

NSDL National Science Digital Library

This site from Malin Space Science Systems provides access to all of the images acquired by the Mars Orbiter Camera (MOC) during the Mars Global Surveyor mission through March 2005. MOC consists of several cameras: A narrow angle system that provides grayscale high resolution views of the planet's surface (typically, 1.5 to 12 meters/pixel), and red and blue wide angle cameras that provide daily global weather monitoring, context images to determine where the narrow angle views were actually acquired, and regional coverage to monitor variable surface features such as polar frost and wind streaks. Ancillary data for each image is provided and instructions regarding gallery usage are also available on the site.

Systems, Malin S.

90

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

PubMed Central

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.

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

2011-01-01

91

Scintillation camera imaging with I-123.  

PubMed

Iodine-123 produced from three different nuclear targets (Te-122, Te-124, and I-127) was evaluated for spatial resolution and sensitivity with an Anger scintillation camera. Te-122 targets generated a substantial amount of I-130, which necessitated use of a medium-energy collimator. Te-124 targets produced solutions with significant amounts of I-124. Shortly after the end of bombardment, a 4,000-hole (4KH) collimator was satisfactory; at 30 hours, a medium-energy collimator was required. High-purity I-123 from an I-127 target gave excellent spatial resolution when the 4KH collimator was used, but low-energy "foil" collimators were not adequate. PMID:760172

Graham, L S; Zielinski, F W

1979-02-01

92

Air Pollution Determination Using a Surveillance Internet Protocol Camera Images  

NASA Astrophysics Data System (ADS)

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

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

93

CCD camera response to diffraction patterns simulating particle images.  

PubMed

We present a statistical study of CCD (or CMOS) camera response to small images. Diffraction patterns simulating particle images of a size around 2-3 pixels were experimentally generated and characterized using three-point Gaussian peak fitting, currently used in particle image velocimetry (PIV) for accurate location estimation. Based on this peak-fitting technique, the bias and RMS error between locations of simulated and real images were accurately calculated by using a homemade program. The influence of the intensity variation of the simulated particle images on the response of the CCD camera was studied. The experimental results show that the accuracy of the position determination is very good and brings attention to superresolution PIV algorithms. Some tracks are proposed in the conclusion to enlarge and improve the study. PMID:23842270

Stanislas, M; Abdelsalam, D G; Coudert, S

2013-07-01

94

Establishing imaging sensor specifications for digital still cameras  

NASA Astrophysics Data System (ADS)

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.

Kriss, Michael A.

2007-03-01

95

Human Body Postures from Trinocular Camera Images  

Microsoft Academic Search

This paper proposes a new real-time method for estimating human postures in 3D from trinocular images. In this method, an upper body orientation detection and a heuristic contour analysis are performed on the human silhouettes extracted from the trinocular images so that representative points such as the top of the head can be located. The major joint positions are estimated

Shoichiro Iwasawa; Jun Ohya; Kazuhiko Takahashi; Tatsumi Sakaguchi; Shigeo Morishima; Kazuyuki Ebihara

2000-01-01

96

Snapshot hyperspectral imaging: the hyperpixel array camera  

Microsoft Academic Search

Hyperspectral imaging has important benefits in remote sensing and material identification. This paper describes a class of hyperspectral imaging systems which utilize a novel optical processor that provides video-rate hyperspectral datacubes. These systems have no moving parts and do not operate by scanning in either the spatial or spectral dimension. They are capable of recording a full three-dimensional (two spatial,

Andrew Bodkin; A. Sheinis; A. Norton; J. Daly; S. Beaven; J. Weinheimer

2009-01-01

97

The research of relay lens coupling in image intensified camera  

NASA Astrophysics Data System (ADS)

Image Intensified CCD (ICCD) camera is widely used in the field of low-light-level image detection. The crucial part of ICCD, coupling component, which realizes the image transmitting between the image intensifier and detector, affects the final performance of the ICCD camera significantly. There are two means of coupling: relay lens and optical fiber taper (OFT). OFT has the merits of small volume and relatively high coupling efficiency, therefore it is commonly used in the portable devices or applications with less precision demands. However, relay lens turns out to be a better solution other than OFT for the applications with no volume and weight restrictions, since it provides higher resolution, perfect image plane uniformity and manufacture flexibility. In this paper, we discuss a methodology of high performance relay lens design and based on the method a solid design is proposed. There are three major merits of the lens design. Firstly, the lens has large object space numerical aperture and thus the coupling efficiency reaches 5% at the magnification of 0.25. Secondly, the lens is telecentric in both sides of object space and image space, this feature guarantees uniform light collection over the field of view and uniform light receiving on the detector plane. Finally, the design can be conveniently optimized to meet the needs of different type of image intensifier. Moreover, the paper presents a prototype ICCD camera and a series of imaging experiment as well. The experiment results prove the validity of the foregoing analysis and optical design.

Sun, Xin; Hu, Bing-liang; Zou, Chun-bo; Bai, Qing-lan; Wang, Le

2013-08-01

98

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

NASA Astrophysics Data System (ADS)

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.

Friedman, Gary L.

1993-11-01

99

Mining Images in Publicly-Available Cameras for Homeland Security  

Microsoft Academic Search

A dramatic increase or decrease in the number of people appearing at a location can be an indicator that something has happened that may be of interest to law-enforcement, public health, or security. This work demonstrates how low quality camera images can be used to automatically alert when an unusual number of people are absent or present at a location.

Latanya Sweeney; Ralph Gross

100

Hyperspectral low-light camera for imaging of biological samples  

Microsoft Academic Search

The capability of acquiring hyperspectral information in low light conditions is potentially important for a variety of applications, ranging from remote sensing to biomedical fluorescence imaging. Particularly interesting is its use in optical analysis of biological samples in which the light level should be kept low to prevent tissue damage. For this purpose a low-light hyperspectral camera has been developed

J. Hernandez-Palacios; L. L. Randeberg; I. Baarstad; T. Loke; T. Skauli

2010-01-01

101

Snapshot hyperspectral imaging: the hyperpixel array camera  

NASA Astrophysics Data System (ADS)

Hyperspectral imaging has important benefits in remote sensing and material identification. This paper describes a class of hyperspectral imaging systems which utilize a novel optical processor that provides video-rate hyperspectral datacubes. These systems have no moving parts and do not operate by scanning in either the spatial or spectral dimension. They are capable of recording a full three-dimensional (two spatial, one spectral) hyperspectral datacube with each video frame, ideal for recording data on transient events, or from unstabilized platforms. We will present the results of laboratory and field-tests for several of these imagers operating in the visible, near-infrared, mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) regions.

Bodkin, Andrew; Sheinis, A.; Norton, A.; Daly, J.; Beaven, S.; Weinheimer, J.

2009-05-01

102

Performance evaluation of digital still camera image processing pipelines  

NASA Astrophysics Data System (ADS)

Although its lens and image sensor fundamentally limit a digital still camera's imaging performance, image processing can significantly improve the perceived quality of the output images. A well-designed processing pipeline achieves a good balance between the available processing power and the image yield (the fraction of images that meet a minimum quality criterion). This paper describes the use of subjective and objective measurements to establish a methodology for evaluating the image quality of processing pipelines. The test suite contains images both of analytical test targets for objective measurements, and of scenes for subjective evaluations that cover the photospace for the intended application. Objective image quality metrics correlating with perceived sharpness, noise, and color reproduction were used to evaluate the analytical images. An image quality model estimated the loss in image quality for each metric, and the individual metrics were combined to estimate the overall image quality. The model was trained with the subjective image quality data. The test images were processed through different pipelines, and the overall objective and subjective data was assessed to identify those image quality metrics that exhibit significant correlation with the perception of image quality. This methodology offers designers guidelines for effectively optimizing image quality.

Hertel, Dirk; Chang, Edward; Shih, Loren; Sproul, Jason

2007-01-01

103

The high resolution gamma imager (HRGI): a CCD based camera for medical imaging  

Microsoft Academic Search

We describe the High Resolution Gamma Imager (HRGI): a Charge Coupled Device (CCD) based camera for imaging small volumes of radionuclide uptake in tissues. The HRGI is a collimated, scintillator-coated, low cost, high performance imager using low noise CCDs that will complement whole-body imaging Gamma Cameras in nuclear medicine. Using 59.5keV radiation from a 241Am source we have measured the

John. E. Lees; George. W. Fraser; Adam Keay; David Bassford; Robert Ott; William Ryder

2003-01-01

104

A novel SPECT camera for molecular imaging of the prostate  

NASA Astrophysics Data System (ADS)

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.

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

2011-09-01

105

Influence of Digital Camera Errors on the Photogrammetric Image Processing  

NASA Astrophysics Data System (ADS)

The paper deals with the calibration of digital camera Canon EOS 350D, often used for the photogrammetric 3D digitalisation and measurements of industrial and construction site objects. During the calibration data on the optical and electronic parameters, influencing the distortion of images, such as correction of the principal point, focal length of the objective, radial symmetrical and non-symmetrical distortions were obtained. The calibration was performed by means of the Tcc software implementing the polynomial of Chebichev and using a special test-field with the marks, coordinates of which are precisely known. The main task of the research - to determine how parameters of the camera calibration influence the processing of images, i. e. the creation of geometric model, the results of triangulation calculations and stereo-digitalisation. Two photogrammetric projects were created for this task. In first project the non-corrected and in the second the corrected ones, considering the optical errors of the camera obtained during the calibration, images were used. The results of analysis of the images processing is shown in the images and tables. The conclusions are given.

Sužiedelyt?-Visockien?, J?rat?; Bru?as, Domantas

2009-01-01

106

Sub-100g uncooled thermal imaging camera design  

NASA Astrophysics Data System (ADS)

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.

Brown, Alistair

2008-10-01

107

Innovative Camera and Image Processing System to Characterize Cryospheric Changes  

NASA Astrophysics Data System (ADS)

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 performed by the Applanix navigation system. Our new method enables a 3D reconstruction of ice sheet surface with high accuracy and unprecedented details, as it is demonstrated by examples from the Antarctic Peninsula, acquired by the IceBridge mission. Repeat digital imaging also provides data for determining surface elevation changes and velocities that are critical parameters for ice sheet models. Although these methods work well, there are known problems with satellite images and the traditional area-based matching, especially over rapidly changing outlet glaciers. To take full advantage of the high resolution, repeat stereo imaging we have developed a new method. The processing starts with the generation of a DEM from geo-referenced stereo images of the first time epoch. The next step is concerned with extracting and matching interest points in object space. Since an interest point moves its spatial position between two time epochs, such points are only radiometrically conjugate but not geometrically. In fact, the geometric displacement of two identical points, together with the time difference, renders velocities. We computed the evolution of the velocity field and surface topography on the floating tongue of the Jakobshavn glacier from historical stereo aerial photographs to illustrate the approach.

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

2010-12-01

108

ARNICA, the NICMOS 3 imaging camera of TIRGO.  

NASA Astrophysics Data System (ADS)

ARNICA (ARcetri Near Infrared CAmera) is the imaging camera for the near infrared bands between 1.0 and 2.5 ?m that Arcetri Observatory has designed and built as a general facility for the TIRGO telescope (1.5 m diameter, f/20) located at Gornergrat (Switzerland). The scale is 1?per pixel, with sky coverage of more than 4 min×4 min on the NICMOS 3 (256×256 pixels, 40 ?m side) detector array. The camera is remotely controlled by a PC 486, connected to the array control electronics via a fiber-optics link. A C-language package, running under MS-DOS on the PC 486, acquires and stores the frames, and controls the timing of the array. The camera is intended for imaging of large extra-galactic and Galactic fields; a large effort has been dedicated to explore the possibility of achieving precise photometric measurements in the J, H, K astronomical bands, with very promising results.

Lisi, F.; Baffa, C.; Hunt, L.; Stanga, R.

109

A four-step camera calibration procedure with implicit image correction  

Microsoft Academic Search

In geometrical camera calibration the objective is to determine a set of camera parameters that describe the mapping between 3-D reference coordinates and 2-D image coordinates. Various methods for camera calibration can be found from the literature. However surprisingly little attention has been paid to the whole calibration procedure, i.e., control point extraction from images, model fitting, image correction, and

Janne Heikkila; O. Silven

1997-01-01

110

Virtual color image synthesis for depth camera using depth-image-based rendering  

Microsoft Academic Search

For each view, the color and depth information are essential to consitute the elements of 3DTV. But in real situations, not all the depth cameras can provide color information. Therefore, propagating color information from reference view to the view of depth camera is important. Depth-Image-Based Rendering (DIBR) has been considered as a crucial technology to create virtual view. However, it

Lu Wang; Ju Liu; Jiande Sun; Wei Liu; Fengli Yu

2011-01-01

111

A parallel image compression system for high-speed cameras  

Microsoft Academic Search

In this paper, we propose a parallel image compression system for high-speed cameras. The proposed compression circuits are based on a 4×4-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

Y. Nishikawa; S. Kawahito; T. Inoue

2005-01-01

112

Parallel image compression circuit for high-speed cameras  

Microsoft Academic Search

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

Yukinari Nishikawa; Shoji Kawahito; Toru Inoue

2005-01-01

113

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

NASA Astrophysics Data System (ADS)

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.

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

2005-02-01

114

Reducing flicker due to ambient illumination in camera captured images  

NASA Astrophysics Data System (ADS)

The flicker artifact dealt with in this paper is the scanning distortion arising when an image is captured by a digital camera using a CMOS imaging sensor with an electronic rolling shutter under strong ambient light sources powered by AC. This type of camera scans a target line-by-line in a frame. Therefore, time differences exist between the lines. This mechanism causes a captured image to be corrupted by the change of illumination. This phenomenon is called the flicker artifact. The non-content area of the captured image is used to estimate a flicker signal that is a key to being able to compensate the flicker artifact. The average signal of the non-content area taken along the scan direction has local extrema where the peaks of flicker exist. The locations of the extrema are very useful information to estimate the desired distribution of pixel intensities assuming that the flicker artifact does not exist. The flicker-reduced images compensated by our approach clearly demonstrate the reduced flicker artifact, based on visual observation.

Kim, Minwoong; Bengtson, Kurt; Li, Lisa; Allebach, Jan P.

2013-02-01

115

Imaging volcanic SO2 plumes with UV cameras  

NASA Astrophysics Data System (ADS)

Ultraviolet (UV) cameras allow the two-dimensional imaging of SO2 distributions at temporal resolutions on the order of 1Hz. Optical bandpass filters that selectively transmit only UV wavelengths at which SO2 absorption occurs (or, for reference, wavelengths at which absorption is negligible) are positioned in the camera's optical system, thus providing selective sensitivity to SO2. As SO2 is one of the main volatile species associated with high-temperature volcanic degassing, UV camera systems are increasingly being applied to volcanic environments for monitoring and research purposes. The relatively high frame rate of these cameras allows the retrieval of SO2 emission fluxes on time scales comparable to those on which other geophysical parameters (e.g. seismicity, deformation) are recorded, thus making an integrated evaluation possible. While impressive imagery of a volcanic plume's extent is readily obtained, lingering challenges include obtaining an accurate SO2 column density calibration, correcting for complex radiative transfer in and around volcanic plumes (which are often visually opaque), and deriving accurate flux measurements truly representative of volcanic activity and not overly biased by atmospheric turbulence and other secondary effects. Here, these issues are addressed, innovative solutions are presented, and example measurements from Kilauea Volcano (Hawaii) are shown. Although time-averaged SO2 emission rates were typically below 10 kg/s (~900 t/d) during measurements in September and October 2011, the high-resolution camera measurements revealed short-period (order of seconds) peaks of more than twice that value. Measurements were taken from different locations between 2 and 7 km distance from the summit vent, thus giving different perspectives of the gas plume. Where possible, links between SO2 emissions and other monitored parameters are identified and interpreted in regard to their connection to physical processes occurring in the volcanic system.

Kern, C.; Werner, C. A.; Doukas, M. P.; Elias, T.; Kelly, P. J.; Sutton, A. J.

2012-04-01

116

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...

117

Digital camera sensing and its image disruption with controlled radio-frequency reception\\/transmission  

Microsoft Academic Search

Photography is becoming more and more end user capability, with many people having digital cameras on their mobile phones. In general digital cameras are phasing out traditional film based equipment. The advantages of digital photography include the compactness of the cameras, high reliability and ease of image processing and transmission of the images via the internet or multimedia messaging (MMS)

Ariel Schwarz; Zeev Zalevsky; Yosef Sanhedrai

2011-01-01

118

Optimization of breast imaging procedure with dedicated compact gamma cameras  

SciTech Connect

Results are presented on studies conducted with various prototypes of a dedicated small field-of-view (SFOV) gamma camera for use in radiopharmaceutical studies of the breast. Since the experience in the clinical use of such instruments is limited, these experiments were conducted to test various clinical imaging implementations. Both planar and tomographic techniques were utilized to image various compressed and noncompressed breast phantoms. Lesion contrast was used to quantify the lesion visibility of each case. The results of this study indicate that lesion contrast is optimized with planar imaging of the compressed breast and that contrast is also dependent on lesion-to-detector distance. Based on these observations, planar imaging conducted with a system comprised of two opposed detectors providing compression to the breast would be optimal. The opposed views would ensure the minimization of lesion-to-detector distance, especially for lesions whose location is not known a-priori.

D. Kieper; S. Majewski; B. Kross; V. Popov; A. G. Weisenberger; B. Welch; R. Wojcik; M. B. Williams; A. R. Goode; M. More; G. Zhang

2003-01-01

119

Imaging of Venus from Galileo: Early results and camera performance  

USGS Publications Warehouse

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.

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

120

First experiences with ARNICA, the ARCETRI observatory imaging camera  

NASA Astrophysics Data System (ADS)

ARNICA (ARcetri Near Infrared CAmera) is the imaging camera for the near infrared bands between 1.0 and 2.5 micrometer that Arcetri Observatory has designed and built as a common use instrument for the TIRGO telescope (1.5 m diameter, f/20) located at Gornergrat (Switzerland). The scale is 1 sec per pixel, with sky coverage of more than 4 min x 4 min on the NICMOS 3 (256 x 256 pixels, 40 micrometer side) detector array. The optical path is compact enough to be enclosed in a 25.4 cm diameter dewar; the working temperature of detector and optics is 76 K. We give an estimate of performance, in terms of sensitivity with an assigned observing time, along with some preliminary considerations on photometric accuracy.

Lisi, F.; Baffa, C.; Hunt, L.; Maiolino, R.; Moriondo, G.; Stanga, R.

1994-03-01

121

Image-intensifier camera studies of shocked metal surfaces  

SciTech Connect

A high-space-resolution image-intensifier camera with luminance gain of up to 5000 and exposure times as short as 30 ns has been applied to the study of the interaction of posts and welds with strongly shocked metal surfaces, which included super strong steels. The time evolution of a single experiment can be recorded by multiple pulsing of the camera. Phenomena that remain coherent for relatively long durations have been observed. An important feature of the hydrodynamic flow resulting from post-plate interactions is the creation of a wave that propagates outward on the plate; the flow blocks the explosive product gases from escaping through the plate for greater than 10 ..mu..s. Electron beam welds were ineffective in blocking product gases from escaping for even short periods of time.

Engelke, R.P.; Thurston, R.S.

1986-01-01

122

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

NASA Astrophysics Data System (ADS)

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.

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

2007-03-01

123

Touchless sensor capturing five fingerprint images by one rotating camera  

NASA Astrophysics Data System (ADS)

Conventional touch-based sensors cannot capture the fingerprint images of all five fingers simultaneously due to their flat surfaces because the view of the thumb is not parallel to the other fingers. In addition, touch-based sensors have inherent difficulties, including variations in captured images due to partial contact, nonlinear distortion, inconsistent image quality, and latent images. These degrade recognition performance and user acceptance to using sensors. To overcome these difficulties, we propose a device that adopts a contact-free structure composed of a charge-coupled device (CCD) camera, rotating mirror equipped with a stepping motor, and a green light-emitting diode (LED) illuminator. The device does not make contact with any finger and captures all five fingerprint images simultaneously. We describe and discuss the structure of the proposed device in terms of four aspects: the quality of captured images, verification performance, compatibility with existing touch-based sensors, and ease of use. The experimental results show that the proposed device can capture all five fingerprint images with a high throughput (in 2.5 s), as required at the immigration control office of a country. Also, on average, a captured touchless image takes 57% of a whole rolled image whereas the image captured from a conventional touch-based sensor only takes 41% of a whole rolled image, and they have 63 and 40 true minutiae on average, respectively. Even though touchless images contain 13.18-deg rolling and 9.18-deg pitching distortion on average, 0% equal error rate (EER) is obtained by using five fingerprint images in verification stage.

Noh, Donghyun; Choi, Heeseung; Kim, Jaihie

2011-11-01

124

Single-quantum dot imaging with a photon counting camera  

PubMed Central

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.

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

2010-01-01

125

Frequency identification of vibration signals using video camera image data.  

PubMed

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

Jeng, Yih-Nen; Wu, Chia-Hung

2012-10-16

126

2D/3D image (facial) comparison using camera matching.  

PubMed

A problem in forensic facial comparison of images of perpetrators and suspects is that distances between fixed anatomical points in the face, which form a good starting point for objective, anthropometric comparison, vary strongly according to the position and orientation of the camera. In case of a cooperating suspect, a 3D image may be taken using e.g. a laser scanning device. By projecting the 3D image onto a 2D image with the suspect's head in the same pose as that of the perpetrator, using the same focal length and pixel aspect ratio, numerical comparison of (ratios of) distances between fixed points becomes feasible. An experiment was performed in which, starting from two 3D scans and one 2D image of two colleagues, male and female, and using seven fixed anatomical locations in the face, comparisons were made for the matching and non-matching case. Using this method, the non-matching pair cannot be distinguished from the matching pair of faces. Facial expression and resolution of images were all more or less optimal, and the results of the study are not encouraging for the use of anthropometric arguments in the identification process. More research needs to be done though on larger sets of facial comparisons. PMID:16337353

Goos, Mirelle I M; Alberink, Ivo B; Ruifrok, Arnout C C

2005-12-06

127

The effect of illumination volume in underwater camera image  

NASA Astrophysics Data System (ADS)

Video cameras are standard equipment on, practically, all of today's underwater robotics vehicles. As a part of a camera system setting, the arrangement of active illumination affects the quality of acquisition, particularly in turbid water environment. Large illumination volume helps to increase image brightness but depresses modulated contrast. This paper elaborates on the effects of illumination volume due to the forward and backward scattering progresses. An intensity model is proposed to include the geometrical parameters of the illumination setup. This model is based on the volume scattering function (VSF) and Lambertian reflection effects. The distribution of scattering noise in the image is predicted for different size of light beam. Experiments were conducted in a short water tank using a continuous wave, 532nm laser light source with an adjustable parallel beam output. In application, as laser beam scanning is a well-known method to improve underwater visibility, the theoretical model helps in determining the optimum illumination setting in different water conditions, and accordingly reducing the time of photomosaicing.

Xu, Lin; Seet, Gerald; He, Duo-Min

2005-04-01

128

A high-precision camera operation parameter measurement system and its application to image motion inferring  

Microsoft Academic Search

Information about camera operations such as zoom, focus, pan, tilt and dollying is significant not only for efficient video coding, but also for content-based video representation. In this paper we describe a high-precision camera operation parameter measurement system and apply it to image motion inferring. First, we outline the implemented system which is designed to provide camera operation parameters with

Wentao Zheng; Yoshiaki Shishikui; Yasuaki Kanatsugu; Yutaka Tanaka; Ichiro Yuyama

2001-01-01

129

Measurement of of color differences of digital cameras from natural images  

Microsoft Academic Search

Traditionally, camera color difference values have been measured using test targets. Test-target measurements are tedious and require a controlled laboratory environment. Compared to images of a real scene, the captured test-target images cannot be utilized for subjective tests. Here, we propose a method for measuring the camera color difference values using a real scene image. The method is based on

Mikko Nuutinen; Pirkko Oittinen

2011-01-01

130

Analysis of Radially Restored Images for Spherical Single Lens Cellphone Camera  

Microsoft Academic Search

A spherical single lens imaging system for cellphone camera is proposed in this research. The overall thickness from the front surface of the lens to the image sensor is approximately 4.5 mm, which is competitive compared to 6~7 mm of current cellphone camera modules that use compound lens system. One defect of this spherical single lens that deteriorates image quality

Yupeng Zhang; Ikumi Minema; Lev G. Zimin; Toshitsugu Ueda

2011-01-01

131

Replacing 16-mm airborne film cameras with commercial-off-the-shelf (COTS) digital imaging  

NASA Astrophysics Data System (ADS)

For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne weapon testing, range tracking, an other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost-effective solution. Film-based cameras still produce the best resolving capability. However, film development time, chemical disposal, non-optimal lighting conditions, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new imager from Kodak that has been designed to replace 16 mm high-speed film cameras. Also included is a detailed configuration, operational scenario, and cost analysis of Kodak's imager for airborne applications. The KODAK EKTAPRO Imager RO Imager is a high-resolution color or monochrome CCD Camera especially designed for replacement of rugged high-speed film cameras. The RO Imager is a record only camera. It features a high-resolution [512 X 384], light-sensitive CCD sensor with an electronic shutter. This shutter provides blooming protection that prevents 'smearing' of bright light sources, e.g., camera looking into a bright sun reflection. The RO Imager is a very rugged camera packaged in a highly integrated housing. This imager operates off +28 VDC. The RO Imager has a similar interface and form factor is that of high-speed film cameras, e.g., Photonics 1B. The RO Imager is designed to replace 16 mm film cameras that support rugged testing applications.

Balch, Kris S.

1998-08-01

132

Image Frequency Analysis for Testing of Fire Service Thermal Imaging Cameras  

Microsoft Academic Search

A growing number of first responders are purchasing infrared cameras (thermal imagers). Thermal imagers provide critical information\\u000a for many firefighting operations: size up, tracking of fire growth, location of victims and egress routes, overhaul, etc….\\u000a Although thermal imagers have proven to be useful tools for the fire service over the past 10–15 years, there is no existing\\u000a comprehensive performance standard for

Francine Amon; Alfred Ducharme

2009-01-01

133

A Hybrid Camera for simultaneous imaging of gamma and optical photons  

NASA Astrophysics Data System (ADS)

We present a new concept for a medical imaging system, the Hybrid Mini Gamma Camera (HMGC). This combines an optical and a gamma-ray camera in a co-aligned configuration that offers high spatial resolution multi-modality imaging for superimposition of a scintigraphic image on an optical image. This configuration provides visual identification of the sites of localisation of radioactivity that would be especially suited to medical imaging. An extension of the new concept using two hybrid cameras (The StereoScope) offers the potential for stereoscopic imaging with depth estimation for a gamma emitting source.

Lees, J. E.; Bassford, D. J.; Blake, O. E.; Blackshaw, P. E.; Perkins, A. C.

2012-06-01

134

A fast focal-reducing camera for CCD imaging  

NASA Astrophysics Data System (ADS)

This paper describes the design and performance of the OREAD focal-reducing camera, constructed for use at the Cassegrain focus of the Michigan-Dartmouth-MIT Observatory McGraw-Hill 1.3-meter telescope. OREAD is an all-refractive optical system providing a 50-mm collimated beam suitable for commercially available narrow-band filters or grisms. Its collimator and field lens are custom-made to decrease the severe coma which would otherwise be present at the extremities of its 30-arc-min field. When used with a CCD such as the TI 800 x 800, OREAD provides a field of view of 0.1 square degree at 1.5 arcsec/pixel. The focal ratio of OREAD of f/1.63 allows sky-limited narrow-band images to be obtained with exposures of only moderate duration. In an Appendix, some limitations inherent in coarsely sampled data obtained with CCDs are examined.

Aldering, Gregory S.; Bothun, Gregory D.

1991-12-01

135

Color calibration of a CMOS digital camera for mobile imaging  

NASA Astrophysics Data System (ADS)

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 ?E94 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.

Eliasson, Henrik

2010-01-01

136

Applying and extending ISO/TC42 digital camera resolution standards to mobile imaging products  

NASA Astrophysics Data System (ADS)

There are no fundamental differences between today's mobile telephone cameras and consumer digital still cameras that suggest many existing ISO imaging performance standards do not apply. To the extent that they have lenses, color filter arrays, detectors, apertures, image processing, and are hand held, there really are no operational or architectural differences. Despite this, there are currently differences in the levels of imaging performance. These are driven by physical and economic constraints, and image-capture conditions. Several ISO standards for resolution, well established for digital consumer digital cameras, require care when applied to the current generation of cell phone cameras. In particular, accommodation of optical flare, shading non-uniformity and distortion are recommended. We offer proposals for the application of existing ISO imaging resolution performance standards to mobile imaging products, and suggestions for extending performance standards to the characteristic behavior of camera phones.

Williams, Don; Burns, Peter D.

2007-01-01

137

Megapixel mythology and photospace: estimating photospace for camera phones from large image sets  

Microsoft Academic Search

It is a myth that more pixels alone result in better images. The marketing of camera phones in particular has focused on their pixel numbers. However, their performance varies considerably according to the conditions of image capture. Camera phones are often used in low-light situations where the lack of a flash and limited exposure time will produce underexposed, noisy and

Bror O. Hultgren; Dirk W. Hertel

2008-01-01

138

Production of Video Images by Computer Controlled Cameras and Its Application to TV Conference System  

Microsoft Academic Search

TV conference systems have been widely used recently. A participant of each site proceeds with a TV conference using video image on a screen and voice of a partner site. In this case, a fixed video camera shoots a scene of a site in general. The video image taken by a fixed camera, how- ever, is lacking in changes. Also

Masaki Onishi; Takehiko Kagebayashi; Kunio Fukunaga

2001-01-01

139

Importance of Developing Image Restoration Techniques for Security Cameras under Severe Conditions  

Microsoft Academic Search

A concept, which was proposed and has been pursued by the authors for restoring the images of a suspected person taken by a security camera, is reviewed. In the concept, the peculiar facts concerning the security camera system that all the things in the image except the suspected person itself are usually preserved and that can be used for investigations

Y. Fujii; T. Ito; N. Ohta; S. Saitoh; T. Matsuura; T. Yamamoto

2006-01-01

140

Ultra-fast MTF Test for High-Volume production of CMOS Imaging Cameras  

Microsoft Academic Search

During the last years compact CMOS imaging cameras have grown into high volume applications such as mobile phones, PDAs, etc. In order to insure a constant quality of the lenses of the cameras, MTF is used as a figure of merit. MTF is a polychromatic, objective test for imaging lens quality including diffraction effects, system aberrations and surface defects as

Michael Dahl; Josef Heinisch; Stefan Krey; Stefan M. Bäumer; Johan Lurquin; Linghua Chen

2004-01-01

141

Alternative Images for Perpendicular Parking: A Usability Test of a Multi-Camera Parking Assistance System.  

National Technical Information Service (NTIS)

The parking assistance system evaluated consisted of four outward facing cameras whose images could be presented on a monitor on the center console. The images presented varied in the location of the virtual eye point of the camera (the height above the v...

B. Cullinane J. Amann P. Green R. Rubin S. Gadgil S. M. Walls

2004-01-01

142

Design and Emulation of a Multiple-Camera SPECT Breast Imager.  

National Technical Information Service (NTIS)

The purpose of this study has been to design and emulate a multiple- camera dedicated SPECT breast imager. The scope of this study involved characterizing radioactivity within a human breast, building breast phantoms for imaging, modeling mean detector re...

J. Sain H. Barrett

2000-01-01

143

Thermophysical Properties of Selected Lunar Study Regions Determined from LROC and Diviner Data  

NASA Astrophysics Data System (ADS)

Using Diviner temperature data combined with subsets of the 100 m grid LROC WAC DTM (GLD100), we derived maps of thermal inertia for different study regions, such as Taurus-Littrow Valley, Aristarchus and Lichtenberg Crater.

Bauch, K. E.; Hiesinger, H.; Robinson, M. S.; Scholten, F.

2011-03-01

144

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

NASA Astrophysics Data System (ADS)

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.

Liu, Yan; Liu, Qianshun; Yu, Feihong

2013-08-01

145

An improved wide-field camera for imaging Earth's plasmasphere at 30.4 nm  

NASA Astrophysics Data System (ADS)

The Extreme Ultraviolet Imager (IMAGE/EUV) aboard NASA's IMAGE mission studied the distribution of singly ionized helium (He+) in the Earth's plasmasphere by imaging its emission at 30.4 nm. This instrument consisted of three separate camera heads, each with a 28° field-of-view, with 0.6°resolution. We describe an improved imaging system that can simultaneously image a 40° field-of-view with 0.45° resolution utilizing only one compact camera head and detector. This improved imager also increases sensitivity over the heritage EUV imager by a factor of four due to improvements in optical coatings, detector technology, and a larger entrance aperture.

Davis, Michael W.; Gladstone, G. Randall; Goldstein, Jerry; Sandel, Bill R.; Greathouse, Thomas K.; Retherford, Kurt D.; Winters, Gregory S.

2013-09-01

146

SCC500: next-generation infrared imaging camera core products with highly flexible architecture for unique camera designs  

NASA Astrophysics Data System (ADS)

A new 4th generation MicroIR architecture is introduced as the latest in the highly successful Standard Camera Core (SCC) series by BAE SYSTEMS to offer an infrared imaging engine with greatly reduced size, weight, power, and cost. The advanced SCC500 architecture provides great flexibility in configuration to include multiple resolutions, an industry standard Real Time Operating System (RTOS) for customer specific software application plug-ins, and a highly modular construction for unique physical and interface options. These microbolometer based camera cores offer outstanding and reliable performance over an extended operating temperature range to meet the demanding requirements of real-world environments. A highly integrated lens and shutter is included in the new SCC500 product enabling easy, drop-in camera designs for quick time-to-market product introductions.

Rumbaugh, Roy N.; Grealish, Kevin; Kacir, Tom; Arsenault, Barry; Murphy, Robert H.; Miller, Scott

2003-09-01

147

High performance imaging streak camera for the National Ignition Facility  

NASA Astrophysics Data System (ADS)

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 electromagnetic interference. A train of temporal ultra-violet 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.

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

2012-12-01

148

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

NASA Astrophysics Data System (ADS)

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.

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

2008-03-01

149

Development of filter exchangeable 3CCD camera for multispectral imaging acquisition  

NASA Astrophysics Data System (ADS)

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.

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

2012-05-01

150

A combined microphone and camera calibration technique with application to acoustic imaging.  

PubMed

We present a calibration technique for an acoustic imaging microphone array, combined with a digital camera. Computer vision and acoustic time of arrival data are used to obtain microphone coordinates in the camera reference frame. Our new method allows acoustic maps to be plotted onto the camera images without the need for additional camera alignment or calibration. Microphones and cameras may be placed in an ad-hoc arrangement and, after calibration, the coordinates of the microphones are known in the reference frame of a camera in the array. No prior knowledge of microphone positions, inter-microphone spacings, or air temperature is required. This technique is applied to a spherical microphone array and a mean difference of 3 mm was obtained between the coordinates obtained with this calibration technique and those measured using a precision mechanical method. PMID:23797248

Legg, Mathew; Bradley, Stuart

2013-06-17

151

Applications of the BAE SYSTEMS MicroIR uncooled infrared thermal imaging cameras  

NASA Astrophysics Data System (ADS)

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.

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

2003-09-01

152

Modelling of Camera Phone Capture Channel for JPEG Colour Barcode Images  

NASA Astrophysics Data System (ADS)

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.

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

153

Reference image method for measuring quality of photographs produced by digital cameras  

NASA Astrophysics Data System (ADS)

Objective image quality metrics can be based on test targets or algorithms. Traditionally, the image quality of digital cameras has been measured using test targets. Test-target measurements are tedious and require a controlled laboratory environment. Algorithm metrics can be divided into three groups: full-reference (FR), reduced-reference (RR) and noreference (NR). FR metrics cannot be applied to the computation of image quality captured by digital cameras because pixel-wise reference images are missing. NR metrics are applicable only when the distortion type is known and the distortion space is low-dimensional. RR metrics provide a tradeoff between NR and FR metrics. An RR metric does not require a pixel-wise reference image; it only requires a set of extracted features. With the aid of RR features, it is possible to avoid problems related to NR metrics. In this study, we evaluate the applicability of RR metrics to measuring the image quality of natural images captured by digital cameras. We propose a method in which reference images are captured using a reference camera. The reference images represented natural reproductions of the views under study. We tested our method using three RR metrics proposed in the literature. The results suggest that the proposed method is promising for measuring the quality of natural images captured by digital cameras for the purpose of camera benchmarking.

Nuutinen, Mikko; Orenius, Olli; Säämänen, Timo; Oittinen, Pirkko

2011-01-01

154

N-band observations of comet Austin 1989cl: first images with the CIOmu camera  

Microsoft Academic Search

We report here on the first observations obtained with the mid-infrared camera C1Omu, mounted on the Canada-France-Hawaii Telescope in May 90. The main originality of this camera relies on its LETI\\/LIR detector array, whose large well capacity (>107 electrons) made easy broad-band imaging observations over the entire atmospheric window (8-13 mum). As an illustration of the camera capabilities, we present

P. O. Lagage; P. Merlin; S. Remy; F. Sibille

1993-01-01

155

Electronic Imaging System Incorporating a Hand-Held Fundus Camera for Canine Ophthalmology  

Microsoft Academic Search

Using an electronic imaging system with a hand-held fundus camera to record fundic variations of the eyes is useful in canine toxicological studies. During the past two decades, a method of fundic ophthalmography using a film-based hand-held fundus camera was developed by the Toxicology Department of Bayer Corporation (Stilwell, Kans.) for recording ocular data. These cameras included the RC-2 and

HUNG D. HOANG; LISA M. BRANT; MARK D. JAKSETIC; STEPHEN G. LAKE; BARRY P. STUART

2001-01-01

156

Cloud detection with the Earth Polychromatic Imaging Camera (EPIC)  

NASA Astrophysics Data System (ADS)

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.

Meyer, K.; Marshak, A.; Lyapustin, A.; Torres, O.; Wang, Y.

2011-12-01

157

Experimental research on thermoelectric cooler for imager camera thermal control  

NASA Astrophysics Data System (ADS)

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.

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

2013-09-01

158

Post injection transmission scanning in a volume imaging PET camera  

SciTech Connect

Quantitative, low noise, measured attenuation correction has been established for the PENN PET 240H Volume Imaging Camera. This is achieved, without septa, using a narrow energy and sinogram position gate to minimize scatter contamination. Twelve minute transmission acquisitions with a 0.5 mCi rod source are adequate for this purpose. Post injection transmission scans (with emission activity in the FOV) suffer from emission contamination simulating transmitted gamma ray flux. This emission contamination may be measured by performing a transmission acquisition with normal transmission energy and position gating but without a transmission source. This contamination is then subtracted from the measured post injection transmission scan. Emission activity within the FOV adds to detector deadtime, whereas only a small fraction of events are accepted into the transmission position gate, resulting in a net loss of scan statistics when compared to pre-injection transmission scanning. Removal of emission contamination and compensation for this excess deadtime results in corrected attenuation coefficients close to pre-injection values. For residual activity levels typical of FDG whole-body cancer and cardiac studies the post injection measurements are within 4% of pre-injection values.

Smith, R.J.; Karp, J.S. (Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Radiology); Muehllehner, G. (UGM Medical Systems, Philadelphia, PA (United States))

1994-08-01

159

Lobate Scarp Modeling with Lunar Reconnaissance Orbiter Camera Digital Terrain Models  

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

160

Relating transverse ray error and light fields in plenoptic camera images  

NASA Astrophysics Data System (ADS)

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. The camera image is 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 resultant image is an array of circular exit pupil images, each corresponding to the overlying lenslet. The position of the lenslet encodes the spatial information of the scene, whereas as the sensor pixels encode the angular information for light incident on the lenslet. The 4D light field is therefore described by the 2D spatial information and 2D angular information captured by the plenoptic camera. In aberration theory, the transverse ray error relates the pupil coordinates of a given ray to its deviation from the ideal image point in the image plane and is consequently a 4D function as well. We demonstrate a technique for modifying the traditional transverse ray error equations to recover the 4D light field of a general scene. In the case of a well corrected optical system, this light field is easily related to the depth of various objects in the scene. Finally, the effects of sampling with both the lenslet array and the camera sensor on the 4D light field data are analyzed to illustrate the limitations of such systems.

Schwiegerling, Jim; Tyo, J. Scott

2013-09-01

161

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

Microsoft Academic Search

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

Dmitry Bakin; Brian Keelan

2008-01-01

162

Measurement of Point-Like Image Coordinates Using a Linear CCD-Camera.  

National Technical Information Service (NTIS)

A TV-camera based on a linear 2000-elements charge-coupled light sensor K1200CL2 has been designed. The camera is designed for measuring charged particle track coordinates. It is used for digitizing images and transferring them to DVK-2 microcomputer. Det...

A. L. Men'shikov V. N. Polyakov V. I. Prikhod'ko

1987-01-01

163

A partition approach for the restoration of camera images of planar and curled document  

Microsoft Academic Search

As camera resolution increases, high-speed non-contact text capture through a digital camera is opening up a new channel for text capture and understanding. Unfortunately, the captured document images are normally coupled with the perspective and geometric distortions that cannot be handled by the existing optical character recognition (OCR) systems. In this paper, we propose a new technique, which is capable

Shijian Lu; Ben M. Chen; Chi Chung Ko

2006-01-01

164

Implicit multiplane 3D camera calibration matrices for stereo image processing  

Microsoft Academic Search

By implicit camera calibration, we mean the process of calibrating cameras without explicitly computing their physical parameters. We introduce a new implicit model based on a generalized mapping between an image plane and multiple, parallel calibration planes (usually between four to seven planes). This paper presents a method of computing a relationship between a point on a three-dimensional (3D) object

James W. McKee; Sherrie J. Burgett

1997-01-01

165

Using a Laser Underwater Camera Image Enhancer for Mine Warfare Applications: What is Gained.  

National Technical Information Service (NTIS)

We present preliminary results from recent test of the LUCIE 2 (Laser Underwater Camera Image Enhancer) conducted in Halifax Harbour, Nova Scotia, Canada. LUCIE 2 is a near compact laser range gated camera (25 cm in diameter, 70 cm in length, and neutrall...

A. D. Weidemann G. R. Fournier J. L. Forand P. Mathieu S. McLean

2002-01-01

166

Compact large FoV gamma camera for breast molecular imaging  

NASA Astrophysics Data System (ADS)

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 in2 square H8520-C12 PSPMTs, which are closely packed and coupled to a NaI(Tl) scintillating array, with individual crystal pixel 2×2×6 mm3 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.

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

167

Dynamic range compression preserving local image contrast for digital video camera  

Microsoft Academic Search

This paper presents a novel dynamic range compression method for digital video cameras. The proposed algorithm is designed to preserve a local image contrast based on a luminance ratio of a pixel to its local surround in attention. In general, digital video cameras are required to maintain the shadow to middle range luminance that includes a main object such as

Yusuke Monobe; Haruo Yamashita; Toshiharu Kurosawa; Hiroaki Kotera

2005-01-01

168

Locating and Decoding EAN-13 Barcodes from Images Captured by Digital Cameras  

Microsoft Academic Search

In this paper, we propose a vision-based technique to locate and decode EAN-13 barcodes from images captured by digital cameras. The ultimate aim of our approach is to enable electronic devices with cameras such as mobile phones and personal digital assistants (PDAs) to act as a barcode reader

Douglas Chai; Florian Hock

2005-01-01

169

Estimation of camera matrix using lidar and aerial images  

NASA Astrophysics Data System (ADS)

This paper focuses on the 2D-3D camera pose estimation using one LiDAR view and one calibrated camera view. The pose estimation employs an intelligent search over the extrinsic camera parameters and uses an error metric based on line-segment matching. The goal of this search process is to estimate the pose parameters without any apriori knowledge and in less processing time. We demonstrated the validity of the proposed approach by experimenting on two sets of perspective views using lines as feature.

Duraisamy, Prakash; Belkhouche, Yassine; Jackson, Stephen; Namuduri, Kamesh; Buckles, Bill

2011-09-01

170

Characterization of a direct detection device imaging camera for transmission electron microscopy.  

PubMed

The complete characterization of a novel direct detection device (DDD) camera for transmission electron microscopy is reported, for the first time at primary electron energies of 120 and 200 keV. Unlike a standard charge coupled device (CCD) camera, this device does not require a scintillator. The DDD transfers signal up to 65 lines/mm providing the basis for a high-performance platform for a new generation of wide field-of-view high-resolution cameras. An image of a thin section of virus particles is presented to illustrate the substantially improved performance of this sensor over current indirectly coupled CCD cameras. PMID:20382479

Milazzo, Anna-Clare; Moldovan, Grigore; Lanman, Jason; Jin, Liang; Bouwer, James C; Klienfelder, Stuart; Peltier, Steven T; Ellisman, Mark H; Kirkland, Angus I; Xuong, Nguyen-Huu

2010-03-25

171

Characterization of a Direct Detection Device Imaging Camera for Transmission Electron Microscopy  

PubMed Central

The complete characterization of a novel Direct Detection Device (DDD) camera for transmission electron microscopy is reported, for the first time at primary electron energies of 120 keV and 200 keV. Unlike a standard Charge Coupled Device (CCD) camera, this device does not require a scintillator. The DDD transfers signal up to 65 lines/mm providing the basis for a high-performance platform for a new generation of wide field-of-view high-resolution cameras. An image of a thin section of virus particles is presented to illustrate the substantially improved performance of this sensor over current indirectly coupled CCD cameras.

Milazzo, Anna-Clare; Moldovan, Grigore; Lanman, Jason; Jin, Liang; Bouwer, James C.; Klienfelder, Stuart; Peltier, Steven T.; Ellisman, Mark H.; Kirkland, Angus I.; Xuong, Nguyen-Huu

2010-01-01

172

Cloud level winds from the Venus Express Monitoring Camera imaging  

NASA Astrophysics Data System (ADS)

Six years of continuous monitoring of Venus by European Space Agency's Venus Express orbiter provides an opportunity to study dynamics of the atmosphere our neighbor planet. Venus Monitoring Camera (VMC) on-board the orbiter has acquired the longest and the most complete so far set of ultra violet images of Venus. These images enable a study the cloud level circulation by tracking motion of the cloud features. The highly elliptical polar orbit of Venus Express provides optimal conditions for observations of the Southern hemisphere at varying spatial resolution. Out of the 2300 orbits of Venus Express over which the images used in the study cover about 10 Venus years. Out of these, we tracked cloud features in images obtained in 127 orbits by a manual cloud tracking technique and by a digital correlation method in 576 orbits. Total number of wind vectors derived in this work is 45,600 for the manual tracking and 391,600 for the digital method. This allowed us to determine the mean circulation, its long-term and diurnal trends, orbit-to-orbit variations and periodicities. We also present the first results of tracking features in the VMC near-IR images. In low latitudes the mean zonal wind at cloud tops (67 ± 2 km following: Rossow, W.B., Del Genio, A.T., Eichler, T. [1990]. J. Atmos. Sci. 47, 2053-2084) is about 90 m/s with a maximum of about 100 m/s at 40-50°S. Poleward of 50°S the average zonal wind speed decreases with latitude. The corresponding atmospheric rotation period at cloud tops has a maximum of about 5 days at equator, decreases to approximately 3 days in middle latitudes and stays almost constant poleward from 50°S. The mean poleward meridional wind slowly increases from zero value at the equator to about 10 m/s at 50°S and then decreases to zero at the pole. The error of an individual measurement is 7.5-30 m/s. Wind speeds of 70-80 m/s were derived from near-IR images at low latitudes. The VMC observations indicate a long term trend for the zonal wind speed at low latitudes to increase from 85 m/s in the beginning of the mission to 110 m/s by the middle of 2012. VMC UV observations also showed significant short term variations of the mean flow. The velocity difference between consecutive orbits in the region of mid-latitude jet could reach 30 m/s that likely indicates vacillation of the mean flow between jet-like regime and quasi-solid body rotation at mid-latitudes. Fourier analysis revealed periodicities in the zonal circulation at low latitudes. Within the equatorial region, up to 35°S, the zonal wind show an oscillation with a period of 4.1-5 days (4.83 days on average) that is close to the super-rotation period at the equator. The wave amplitude is 4-17 m/s and decreases with latitude, a feature of the Kelvin wave. The VMC observations showed a clear diurnal signature. A minimum in the zonal speed was found close to the noon (11-14 h) and maxima in the morning (8-9 h) and in the evening (16-17 h). The meridional component peaks in the early afternoon (13-15 h) at around 50°S latitude. The minimum of the meridional component is located at low latitudes in the morning (8-11 h). The horizontal divergence of the mean cloud motions associated with the diurnal pattern suggests upwelling motions in the morning at low latitudes and downwelling flow in the afternoon in the cold collar region.

Khatuntsev, I. V.; Patsaeva, M. V.; Titov, D. V.; Ignatiev, N. I.; Turin, A. V.; Limaye, S. S.; Markiewicz, W. J.; Almeida, M.; Roatsch, Th.; Moissl, R.

2013-09-01

173

Development of gamma ray imaging cameras. Progress report for second year  

SciTech Connect

In January 1990, the Department of Energy initiated this project with the objective to develop the technology for general purpose, portable gamma ray imaging cameras useful to the nuclear industry. The ultimate goal of this R&D initiative is to develop the analog to the color television camera where the camera would respond to gamma rays instead of visible photons. The two-dimensional real-time image would be displayed would indicate the geometric location of the radiation relative to the camera`s orientation, while the brightness and ``color`` would indicate the intensity and energy of the radiation (and hence identify the emitting isotope). There is a strong motivation for developing such a device for applications within the nuclear industry, for both high- and low-level waste repositories, for environmental restoration problems, and for space and fusion applications. At present, there are no general purpose radiation cameras capable of producing spectral images for such practical applications. At the time of this writing, work on this project has been underway for almost 18 months. Substantial progress has been made in the project`s two primary areas: mechanically-collimated (MCC) and electronically-collimated camera (ECC) designs. We present developments covering the mechanically-collimated design, and then discuss the efforts on the electronically-collimated camera. The renewal proposal addresses the continuing R&D efforts for the third year effort. 8 refs.

Wehe, D.K.; Knoll, G.F.

1992-05-28

174

Motion and Structure Estimation of Manoeuvring Objects in Multiple-Camera Image Sequences.  

National Technical Information Service (NTIS)

Estimation of structure and six-degree-of-freedom motion of maneuvering objects through measurements of feature positions in long, multiple-camera image sequences is widely recognized to have broad industrial military and space applications, particularly ...

V. C. Aitken

1992-01-01

175

Simple camera calibration from a single image using five points on two orthogonal 1-D objects.  

PubMed

We propose a simple and practical calibration technique that effectively estimates camera parameters from just five points on two orthogonal 1-D objects, each which has three collinear points, one of which is shared. We derive the basic equations needed to realize camera calibration from just five points observed on a single image that captures the objects. We describe a new camera calibration algorithm that estimates the camera parameters based on the basic equations and optimizes them by the bundle adjustment technique. Our method is validated by both computer simulated data and real images. The results show that the camera parameters yielded by our method are close to those yielded by existing methods. The tests demonstrate that our method is both effective and practical. PMID:20129859

Miyagawa, Isao; Arai, Hiroyuki; Koike, Hideki

2010-02-02

176

Modulated electron-multiplied fluorescence lifetime imaging microscope: all-solid-state camera for fluorescence lifetime imaging  

NASA Astrophysics Data System (ADS)

We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The first stage of evaluation for the camera has been carried out. Camera characteristics such as noise distribution, dark current influence, camera gain, sampling density, sensitivity, linearity of photometric response, and optical transfer function have been studied through experiments. We are able to do lifetime measurement using our modulated, electron-multiplied fluorescence lifetime imaging microscope (MEM-FLIM) camera for various objects, e.g., fluorescein solution, fixed green fluorescent protein (GFP) cells, and GFP-actin stained live cells. A detailed comparison of a conventional microchannel plate (MCP)-based FLIM system and the MEM-FLIM system is presented. The MEM-FLIM camera shows higher resolution and a better image quality. The MEM-FLIM camera provides a new opportunity for performing frequency-domain FLIM.

Zhao, Qiaole; Schelen, Ben; Schouten, Raymond; van den Oever, Rein; Leenen, René; van Kuijk, Harry; Peters, Inge; Polderdijk, Frank; Bosiers, Jan; Raspe, Marcel; Jalink, Kees; de Jong, Jan Geert Sander; van Geest, Bert; Stoop, Karel; Young, Ian Ted

2012-12-01

177

Remarks on 3D human body posture reconstruction from multiple camera images  

Microsoft Academic Search

This paper proposes a human body posture estimation method based on back projection of human silhouette images extracted from multi-camera images. To achieve real-time 3D human body posture estimation, a server-client system is introduced into the multi-camera system, improvements of the background subtraction and back projection are investigated. To evaluate the feasibility of the proposed method, 3D estimation experiments of

Yusuke Nagasawa; Takako Ohta; Yukiko Mutsuji; Kazuhiko Takahashi; Masafumi Hashimoto

2007-01-01

178

Removal of Specular Reflection Based on High-Speed Camera Images  

NASA Astrophysics Data System (ADS)

High speed cameras have the ability to detect luminance variation due to the alternating current of illuminations. On the basis of the luminance variation, this paper proposes a method to estimate an image of when one of the illuminations is nonluminous. If the nonluminous illumination is the source of specular reflection, the estimated image only includes diffuse reflection components of other illuminations. Experimental results in various conditions show that specular reflection components are eliminated without the displacement of a camera or an illumination.

Tsuji, Toshiaki; Inoda, Ryosuke

179

An Automatic Image Reduction Pipeline for the Advanced Camera for Surveys  

Microsoft Academic Search

We have written an automatic image processing pipeline for the Advanced\\u000aCamera for Surveys (ACS) Guaranteed Time Observation (GTO) program. The\\u000apipeline, known as Apsis, supports the different cameras available on the ACS\\u000ainstrument and is written in Python with a flexible object-oriented design that\\u000asimplifies the incorporation of new pipeline modules. The processing steps\\u000ainclude empirical determination of image

John P. Blakeslee; Kenneth R. Anderson; G. R. Meurer; N. Ben ´ itez; D. Magee

2002-01-01

180

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

NASA Astrophysics Data System (ADS)

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.

Lock, Andrew; Amon, Francine

2008-05-01

181

Video-rate or high-precision: a flexible range imaging camera  

Microsoft Academic Search

A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a

Adrian A. Dorrington; Michael J. Cree; Dale A. Carnegie; Andrew D. Payne; Richard M. Conroy; John P. Godbaz; Adrian P. P. Jongenelen

2008-01-01

182

A high speed camera system based on an image sensor in standard CMOS technology  

Microsoft Academic Search

In this contribution a novel camera system developed for high speed imaging will be presented. The core of the system consists of a CMOS image sensor manufactured in a 1 ?m standard CMOS process. The special merit of the image sensor is the capability to acquire more than 1000 frames\\/s using a global electronic shutter in each sensor cell. The

Nenad Stevanovic; Matthias Hillebrand; Bedrich J. Hosticka; Uri Iurgel; Andreas Teuner

1999-01-01

183

3D Image Display with Motion Parallax by Camera Matrix Stereo  

Microsoft Academic Search

We propose a 3D image display system which can present real scenes with realistic motion parallax. In the sensing system, a scene is observed by using a camera matrix. An excellent stereo algorithm SEA which utilizes 3×3 image matrix recovers the depth information of the scene with the density and the sharpness required for high quality image generation. In the

Kiyohide Satoh; Itaru Kitahara; Yuichi Ohta

1996-01-01

184

Myocardial perfusion imaging with an ultra-fast cardiac SPECT camera - a phantom study  

Microsoft Academic Search

Myocardial perfusion imaging is currently the most frequently used nuclear medicine test. Recently, several alternative approaches to myocardial perfusion SPECT imaging have been evaluated. In this study, we compare imaging capabilities of the new ultra-fast cardiac (UFC) system developed by GE Healthcare to a conventional cardiac SPECT camera (Ventri, GE Healthcare). The UFC system uses an array of Cadmium Zinc

L. Volokh; C. Lahat; E. Binyamin; I. Blevis

2008-01-01

185

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

SciTech Connect

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.

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

2005-08-08

186

Source camera identification for heavily JPEG compressed low resolution still images.  

PubMed

In this research, we examined whether fixed pattern noise or more specifically Photo Response Non-Uniformity (PRNU) can be used to identify the source camera of heavily JPEG compressed digital photographs of resolution 640 x 480 pixels. We extracted PRNU patterns from both reference and questioned images using a two-dimensional Gaussian filter and compared these patterns by calculating the correlation coefficient between them. Both the closed and open-set problems were addressed, leading the problems in the closed set to high accuracies for 83% for single images and 100% for around 20 simultaneously identified questioned images. The correct source camera was chosen from a set of 38 cameras of four different types. For the open-set problem, decision levels were obtained for several numbers of simultaneously identified questioned images. The corresponding false rejection rates were unsatisfactory for single images but improved for simultaneous identification of multiple images. PMID:19432739

Alles, Erwin J; Geradts, Zeno J M H; Veenman, Cor J

2009-05-01

187

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

PubMed

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

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

2012-07-25

188

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

NASA Astrophysics Data System (ADS)

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.

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

2008-11-01

189

Comparison of DEMs from Terrain Mapping Camera Images with LOLA  

NASA Astrophysics Data System (ADS)

DEMs generated from the TMC camera are compared with LDEM-256. TMC DEMs are of high quality and accurate, which enables the contruction of three-dimensional models. They are representative of the stability of the platform and the potential of CH-1 for accurate lunar referencing.

Krishna Sumanth, T.; Nagasubramanian, V.; Radhadevi, P. V.; Sudheer Reddy, D.; Solanki, S. S.; Jyothi, M. V.; Saibaba, J.; Varadan, G.

2012-03-01

190

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...

191

Wide-area surveillance with multiple cameras using distributed compressive imaging  

NASA Astrophysics Data System (ADS)

In order to image a large area with a required resolution, a traditional camera would have to scan a smaller field-of-view until the entire area of interest is covered, thus losing persistence. Using a large sensor would result in high bandwidth data streams along with expensive and heavy equipment. Ideally, one would like to sense (or measure) a large number of pixels with a very limited set of measurements. In such a scenario the theory of compressive sensing may be put to use. A single sensor compressive imager for the wide area surveillance problem has been postulated and shown to be effective in detecting moving targets in a wide area. In this paper we look at the compressive imaging problem by assuming we have multiple cameras at our disposal. We show that we can get significant benefit in image reconstruction from multiple cameras measuring overlapped fields-of-view without any intra-camera communications and under significant transmission bandwidth constraints. We also show analysis and experiments which suggest that we can register these multiple cameras given only the random projective measurements from each camera.

Huff, Christopher; Muise, Robert

2011-04-01

192

Evaluation of the clinical practicability of intraoperative optical imaging comparing three different camera setups.  

PubMed

Intraoperative optical imaging (IOI) is a method to visualize functional activated brain areas during brain surgery using a camera system connected to a standard operating microscope. Three different high-resolution camera systems (Hamamatsu EB-CCD C7190-13W, Hamamatsu C4742-96-12G04, and Zeiss AxioCam MRm) have been evaluated for suitability to detect activated brain areas by detecting stimulation-dependent blood volume changes in the somatosensory cerebral cortex after median nerve stimulation. The image quality of the camera systems was evaluated in 14 patients with tumors around the somatosensory cortex. The intraoperative images of the brain surface were continuously recorded over 9 min. With all three camera systems, the activity maps of the median nerve area could be visualized. The image quality of a highly sensitive electron-bombarded camera was up to 10-fold lower compared with two less sensitive standard cameras. In each IOI-positive case, the activated area was in accordance with the anatomical and neurophysiological location of the corresponding cortex. The technique was found to be very sensitive, and several negative influencing factors were identified. However, all possible artifacts seem to be controllable in the majority of the cases, and the IOI method could be well adapted for routine clinical use. Nevertheless, further systematic studies are needed to demonstrate the reliability and validity of the method. PMID:23740654

Sobottka, Stephan B; Meyer, Tobias; Kirsch, Matthias; Koch, Edmund; Steinmeier, Ralf; Morgenstern, Ute; Schackert, Gabriele

2013-06-01

193

High speed short wave infrared (SWIR) imaging and range gating cameras  

NASA Astrophysics Data System (ADS)

Imaging in the Short Wave Infrared (SWIR) provides unique surveillance capabilities, both with passive illumination from the night glow in the atmosphere or with active illumination from covert LED or eye-safe lasers. Spectral effects specific to the 0.9 to 1.7 um wavelength range reveal camouflage and chemical signatures of ordinance. The longer wavelength range also improves image resolution over visible cameras in foggy or dusty environments. Increased military interest in cameras that image all laser range finders and target designators on the battlefield has driven development of a new class of uncooled InGaAs cameras with higher resolution and larger field of view than previously available. Current and upcoming needs include: imaging in all lighting conditions, from direct sunlight to partial starlight while using minimal power; range gating the camera to image through obscurants or beyond unimportant objects; and high speed capture of muzzle flare, projectile tracking, guide star and communications laser-beam tracking and wavefront correction. This paper will present images from new COTS cameras now available to address these needs and discuss the technology roadmap for further improvements.

Malchow, Douglas; Battaglia, Jesse; Brubaker, Robert; Ettenberg, Martin

2007-04-01

194

Optical characterization of UV multispectral imaging cameras for SO2 plume measurements  

NASA Astrophysics Data System (ADS)

Only a few years ago spectral imaging cameras for SO2 plume monitoring were developed for remote sensing of volcanic plumes. We describe the development from a first camera using a single filter in the absorption band of SO2 to more advanced systems using several filters and an integrated spectrometer. The first system was based on the Hamamatsu C8484 UV camera (1344 x 1024 pixels) with high quantum efficiency in the UV region from 280 nm onward. At the heart of the second UV camera system, EnviCam, is a cooled Alta U47 camera, equipped with two on-band (310 and 315 nm) and two off-band (325 and 330 nm) filters. The third system utilizes again the uncooled Hamamatsu camera for faster sampling (~10 Hz) and a four-position filter-wheel equipped with two 10 nm filters centered at 310 and 330 nm, a UV broadband view and a blackened plate for dark-current measurement. Both cameras have been tested with lenses with different focal lengths. A co-aligned spectrometer provides a ~0.3nm resolution spectrum within the field-of-view of the camera. We describe the ground-based imaging cameras systems developed and utilized at our Institute. Custom made cylindrical quartz calibration cells with 50 mm diameter, to cover the entire field of view of the camera optics, are filled with various amounts of gaseous SO2 (typically between 100 and 1500 ppm•m). They are used for calibration and characterization of the cameras in the laboratory. We report about the procedures for monitoring and analyzing SO2 path-concentration and fluxes. This includes a comparison of the calibration in the atmosphere using the SO2 cells versus the SO2 retrieval from the integrated spectrometer. The first UV cameras have been used to monitor ship emissions (Ny-Ålesund, Svalbard and Genova, Italy). The second generation of cameras were first tested for industrial stack monitoring during a field campaign close to the Rovinari (Romania) power plant in September 2010, revealing very high SO2 emissions (> 1000 ppm•m). The second generation cameras are now used by students from several universities in Romania. The newest system has been tested for volcanic plume monitoring at Turrialba, Costa Rica in January, 2011, at Merapi volcani, Indonesia in February 2011, at Lascar volcano in Chile in July 2011 and at Etna/Stromboli (Italy) in November 2011. Retrievals from some of these campaigns will be presented.

Stebel, K.; Prata, F.; Dauge, F.; Durant, A.; Amigo, A.,

2012-04-01

195

High-resolution position-sensitive proportional counter camera for radiochromatographic imaging  

SciTech Connect

A high-resolution proportional counter camera for imaging two- dimensional (2-D) distributions of radionuclides is described. The camera can accommodate wet or dry samples that are separated from the counter gas volume by a 6-..mu..m Mylar membrane. Using 95% Xe-5% CO/sub 2/ gas at 3-MPa pressure and electronic collimation based upon pulse energy discrimination, the camera's performance characteristics for /sup 14/C distributions are as follows: active area--10 by 10 cm, position resolution--0.5 mm, total background--300 disintegrations per minute, and count-rate capability--10/sup 5/ disintegrations per second. With computerized data acquisition, the camera is a significant improvement in analytical instrumentation for imaging 2-D radionuclide distributions over present-day commercially available technology. (Note: This manuscript was completed in July 1983). 13 refs., 10 figs.

Schuresko, D.D.; Kopp, M.K.; Harter, J.A.; Bostick, W.D.

1988-12-01

196

Practical method to derive nonlinear response functions of cameras for scientific imaging.  

PubMed

We developed a practical method to derive response functions that convert the amount of incident light to the counts of analog-to-digital conversion (A/D) of cameras for scientific imaging. In this method, we need a mechanism to accurately control the amount of incident light into cameras just within a limited dynamic range and at a limited number of steps. A variable brightness light source, which supplies the incident light into cameras, is also necessary, but we do not need to know its accurate brightness. Thus, this method enables us to derive the nonlinear response functions accurately with such a simple setup. PMID:21629319

Hanaoka, Yoichiro; Suzuki, Isao; Sakurai, Takashi

2011-06-01

197

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

SciTech Connect

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.

Earnhart, J.R.D.

1998-12-31

198

Superresolution imaging in optical tweezers using high-speed cameras  

Microsoft Academic Search

High-speed cameras are reliable alternatives for the direct characterization of optical trap force and particle motion in optical tweezers setups, replacing indirect motion measurements often performed by quadrant detectors. In the present approach, subpixel motion data of the trapped particle is retrieved from a high-speed low-resolution video sequence. Due to the richness structure of motion diversity of microscopic trapped particles,

Juan Pablo Staforelli; Esteban Vera; Jos'e Manuel Brito; Pablo Solano; Sergio Torres; Carlos Saavedra

2010-01-01

199

Design Considerations Of A Compton Camera For Low Energy Medical Imaging  

SciTech Connect

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.

Harkness, L. J.; Boston, A. J.; Boston, H. C.; Cresswell, J. R.; Grint, A. N.; Judson, D. S.; Nolan, P. J.; Oxley, D. C. [Department of Physics, University of Liverpool, Oliver Lodge Laboratory, Liverpool, UK L697ZE (United Kingdom); Lazarus, I.; Simpson, J. [STFC Daresbury Laboratory, Daresbury, Warrington, WA44AD (United Kingdom)

2009-12-02

200

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

SciTech Connect

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.

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

1984-10-03

201

Single-fluorophore imaging with an unmodified epifluorescence microscope and conventional video camera  

Microsoft Academic Search

Summary Single fluorophores in aqueous solution were imaged in real time with a conventional silicon-intensified target video camera connected to an unmodified commercial micro- scope (IX70, Olympus) with epifluorescence excitation with a high-pressure mercury lamp. Neither a powerful laser nor an extremely sensitive video camera was required. Three experimental systems were used to demonstrate quantita- tively that individual, moving or

Adachi; Kinosita JR; Ando

1999-01-01

202

Spectroscopic Imaging Observation of Break Arcs using a High-speed Camera  

Microsoft Academic Search

Break arcs occurring between electrical contacts are observed in DC42V resistive circuit using a high-speed camera. Materials of contact pairs are Ag or Ag\\/ZnO. The break current is 10A. Spectroscopic images are obtained using the high-speed camera with optical band pass filters. The filters are attached on the lens to observe only the Agl 521 nm or ZnI 481 nm

J. Sekikawa; T. Kubono

2007-01-01

203

Image-based visual PID control of a micro helicopter using a stationary camera  

Microsoft Academic Search

This paper proposes an image-based visual servo control method for a micro helicopter. The helicopter does not have any sensors to measure its position or posture on the body. A stationary camera is placed on the ground, and it obtains image features of the helicopter. The differences between current features and given reference features are computed. PID controllers then make

Kei Watanabe; Yuta Yoshihata; Yasushi Iwatani; Koichi Hashimoto

2007-01-01

204

A Comprehensive Market Analysis on Camera and Illumination Sensors for Image Processing and Machine Vision Applications  

Microsoft Academic Search

In the present industrial application space, conventional inspection techniques using manual intervention are getting replaced by automated inspection using image sensors. Image sensors have empowered machines with vision and that has led to increased levels of process automation which used to be manually exhaustive. This paper mainly focuses on the comparative study of Machine Vision hardware aspect specifically on cameras

Ayan Chaki; M. Prashant; P. Sen

2010-01-01

205

Automatic Compensation for Camera Settings for Images Taken under Different Illuminants  

Microsoft Academic Search

The combination of two images shot for the same scene but under different illumination has been used in wide applications ranging from estimating scene illumination, to enhancing pho- tographs shot in dark environments, to shadow removal. An ex- ample is the use of a pair of images shot with and without a flash. However, for consumer-grade digital cameras, due to

Cheng Lu; Mark S. Drew

2006-01-01

206

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...

207

Removal of Specular Reflection Based on High-Speed Camera Images  

Microsoft Academic Search

High speed cameras have the ability to detect luminance variation due to the alternating current of illuminations. On the basis of the luminance variation, this paper proposes a method to estimate an image of when one of the illuminations is nonluminous. If the nonluminous illumination is the source of specular reflection, the estimated image only includes diffuse reflection components of

Toshiaki Tsuji; Ryosuke Inoda

2010-01-01

208

Planar microwave imaging camera for biomedical applications: Critical and prospective analysis of reconstruction algorithms  

Microsoft Academic Search

This paper is dealing with the biomedical applications of active microwave imaging. As a result of extensive preliminary evaluations conducted by means of a 2.45-GHz planar camera, it has been proven that active microwave imaging is able to provide a very sensitive means of investigation in such applications. While technological problems have been conveniently solved, the main problem still remains

J. C. Bolomey; C. Pichot; G. Garboriaud

1991-01-01

209

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

Microsoft Academic Search

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

Andrew Lock; Francine Amon

2008-01-01

210

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

PubMed

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

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

211

Validation of 3D surface imaging in breath-hold radiotherapy for breast cancer: one central camera unit versus three camera units  

NASA Astrophysics Data System (ADS)

In this work we investigated the benefit of the use of two lateral camera units additional to a central camera unit for 3D surface imaging for image guidance in deep-inspiration breath-hold (DIBH) radiotherapy by comparison with cone-beam computed tomography (CBCT). Ten patients who received DIBH radiotherapy after breast-conserving surgery were included. The performance of surface imaging using one and three camera units was compared to using CBCT for setup verification. Breast-surface registrations were performed for CBCT as well as for 3D surfaces, captured concurrently with CBCT, to planning CT. The resulting setup errors were compared with linear regression analysis. For the differences between setup errors an assessment of the group mean, systematic error, random error, and 95% limits of agreement was made. Correlations between derived surface-imaging [one camera unit;three camera units] and CBCT setup errors were: R2=[0.67;0.75], [0.76;0.87], [0.88;0.91] in left-right, cranio-caudal, and anterior-posterior direction, respectively. Group mean, systematic and random errors were slightly smaller (sub-millimeter differences) and the limits of agreement were 0.10 to 0.25cm tighter when using three camera units compared with one. For the majority of the data, the use of three camera units compared with one resulted in setup errors more similar to the CBCT derived setup errors for the craniocaudal and anterior-posterior directions (p<0.01, Wilcoxon-signed-ranks test). This study shows a better correlation and agreement between 3D surface imaging and CBCT when three camera units are used instead of one and further outlines the conditions under which the benefit of using three camera units is significant.

Alderliesten, Tanja; Betgen, Anja; van Vliet-Vroegindeweij, Corine; Remeijer, Peter

2013-03-01

212

Hybrid Compton camera/coded aperture imaging system  

DOEpatents

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.

Mihailescu, Lucian (Livermore, CA); Vetter, Kai M. (Alameda, CA)

2012-04-10

213

Autofluorescence Images with Carl Zeiss versus Topcon Eye Fundus Camera: A Comparative Study.  

PubMed

Purpose. To compare the autofluorescence images of the Zeiss versus Topcon eye fundus cameras and design an objective way to quantify it. Procedures. The IMAGEJ software was used to determine the gray level corresponding to the darkest veins and the peripapillary ring (thresholds), the level of white of the brightest perifoveal area, their difference (contrast level), and the suprathreshold area for each photograph. Results. Carl Zeiss has higher contrast values than Topcon. The Topcon contrast presented a crest with further decline as the suprathreshold area continued to increase. On the contrary, the Zeiss profile did not decline in contrast. Conclusions and Message. The Carl Zeiss camera showed superior contrast ability over the Topcon when performing autofluorescence imaging. We set objective parameters to compare fundus cameras FAF images. These parameters could be the base to objectively measure and determine changes and realize followup to areas of hyper- or hypofluorescence. PMID:23710331

Muñoz, Juan M; Coco, Rosa M; Sanabria, M Rosa; Cuadrado, Ruben; Blanco, Eduardo

2013-04-22

214

Evolution of INO Uncooled Infrared Cameras Towards Very High Resolution Imaging  

NASA Astrophysics Data System (ADS)

Along the years INO has been involved in development of various uncooled infrared devices. Todays, the infrared imagers exhibit good resolutions and find their niche in numerous applications. Nevertheless, there is still a trend toward high resolution imaging for demanding applications. At the same time, low-resolution for mass market applications are sought for low-cost imaging solutions. These two opposite requirements reflect the evolution of infrared cameras from the origin, when only few pixel-count FPAs were available, to megapixel-count FPA of the recent years. This paper reviews the evolution of infrared camera technologies at INO from the uncooled bolometer detector capability up to the recent achievement of 1280×960 pixels infrared camera core using INO's patented microscan technology.

Bergeron, Alain; Jerominek, Hubert; Chevalier, Claude; Le Noc, Loïc; Tremblay, Bruno; Alain, Christine; Martel, Anne; Blanchard, Nathalie; Morissette, Martin; Mercier, Luc; Gagnon, Lucie; Couture, Patrick; Desnoyers, Nichola; Demers, Mathieu; Lamontagne, Frédéric; Lévesque, Frédéric; Verreault, Sonia; Duchesne, François; Lambert, Julie; Girard, Marc; Savard, Maxime; Châteauneuf, François

2011-02-01

215

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

NASA Astrophysics Data System (ADS)

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 the vehicle. The DOE-SIR method was exercised for determining the optimal camera position and orientation for viewing vehicle rear seats over a variety of vehicle types. The resulting camera geometry was used on public roadway image capture resulting in over 95% acceptable rear seat images for human viewing.

Paul, Peter; Hoover, Martin; Rabbani, Mojgan

2013-03-01

216

A calibration-and-error correction method for improved texel (fused ladar/digital camera) images  

NASA Astrophysics Data System (ADS)

The fusion of imaging ladar information and digital imagery results in 2.5-D surfaces covered with texture information. Called "texel images," these datasets, when taken from dierent viewpoints, can be combined to create 3-D images of buildings, vehicles, or other objects. These 3-D images can then be further processed for automatic target recognition, or viewed in a 3-D viewer for tactical planning purposes. This paper presents a procedure for calibration, error correction, and fusing of ladar and digital camera information from a single hand-held sensor to create accurate texel images. A brief description of a prototype sensor is given, along with calibration technique used with the sensor, which is applicable to other imaging ladar/digital image sensor systems. The method combines systematic error correction of the ladar data, correction for lens distortion of the digital camera image, and fusion of the ladar to the camera data in a single process. The result is a texel image acquired directly from the sensor. Examples of the resulting images, with improvements from the proposed algorithm, are presented.

Budge, Scott E.

2012-05-01

217

Intial synchroscan streak camera imaging at the A0 photoinjector  

SciTech Connect

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.

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

2008-04-01

218

Dynamic imaging with high resolution time-of-flight pet camera - TOFPET I  

SciTech Connect

One of the major design goals of the TOFPET I positron camera was to produce a high resolution whole body positron camera capable of dynamically imaging an organ such as the heart. TOFPET I is now nearing completion and preliminary images have been obtained to assess its dynamic and three dimensional imaging capabilities. Multiple gated images of the uptake of Rubidium in the dog heart and three dimensional surface displays of the distribution of the Rubidium-82 in the myocardium have been generated to demonstrate the three dimensional imaging properties. Fast dynamic images of the first pass of a bolus of radio-tracer through the heart have been collected with 4 second integration time and 50% gating (2 second equivalent integration time) with 18 mCi of Rb-82.

Mullani, N.A.; Bristow, D.; Gaeta, J.; Gould, K.L.; Hartz, R.K.; Philipe, E.A.; Wong, W.H.; Yerian, K.

1984-02-01

219

Nuclear magnetic resonance and gamma camera tumor imaging using gadolinium-labeled monoclonal antibodies  

SciTech Connect

Chelate-derivatized monoclonal antibody labeled with paramagnetic gadolinium-3+ ion has been evaluated as a tumor-specific contrast-enhancing agent in nuclear magnetic resonance imaging in the Rauscher murine erythroleukemia system. With 10(-7) M concentrations of Gd3+ delivered to the tumor target, a small but reproducible difference in proton relaxation times (T1S) was observed in excised tumors. Nuclear magnetic resonance imaging of animals, however, failed to show significant contrast enhancement of the tumor; by comparison, gamma camera images with 153Gd-labeled specific antibody did permit clear tumor visualization without subtraction. The potential use of monoclonal antibodies in tumor imaging appears to be far greater in gamma camera and positron imaging than in nuclear magnetic resonance imaging.

Anderson-Berg, W.T.; Strand, M.; Lempert, T.E.; Rosenbaum, A.E.; Joseph, P.M.

1986-06-01

220

Image processing for three-dimensional scans generated by time-of-flight range cameras  

NASA Astrophysics Data System (ADS)

Time-of-flight (TOF) full-field range cameras use a correlative imaging technique to generate three-dimensional measurements of the environment. Though reliable and cheap they have the disadvantage of high measurement noise and errors that limit the practical use of these cameras in industrial applications. We show how some of these limitations can be overcome with standard image processing techniques specially adapted to TOF camera data. Additional information in the multimodal images recorded in this setting, and not available in standard image processing settings, can be used to improve reduction of measurement noise. Three extensions of standard techniques, wavelet thresholding, adaptive smoothing on a clustering based image segmentation, and an extended anisotropic diffusion filtering, make use of this information and are compared on synthetic data and on data acquired from two different off-the-shelf TOF cameras. Of these methods, the adapted anisotropic diffusion technique gives best results, and is implementable to perform in real time using current graphics processing unit (GPU) hardware. Like traditional anisotropic diffusion, it requires some parameter adaptation to the scene characteristics, but allows for low visualization delay and improved visualization of moving objects by avoiding long averaging periods when compared to traditional TOF image denoising.

Schöner, Holger; Bauer, Frank; Dorrington, Adrian; Heise, Bettina; Wieser, Volkmar; Payne, Andrew; Cree, Michael J.; Moser, Bernhard

2012-04-01

221

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

NASA Astrophysics Data System (ADS)

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.

Bakin, Dmitry; Keelan, Brian

2008-08-01

222

ROSA: A High-cadence, Synchronized Multi-camera Solar Imaging System  

NASA Astrophysics Data System (ADS)

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. The system is available on the Dunn Solar Telescope at the National Solar Observatory in Sunspot, New Mexico, USA, as a common-user instrument. Consisting of six 1k × 1k Peltier-cooled frame-transfer CCD cameras with very low noise (0.02 - 15 e s-1 pixel-1), each ROSA camera is capable of full-chip readout speeds in excess of 30 Hz, or 200 Hz when the CCD is windowed. Combining multiple cameras and fast readout rates, ROSA will accumulate approximately 12 TB of data per 8 hours observing. Following successful commissioning during August 2008, ROSA will allow for multi-wavelength studies of the solar atmosphere at a high temporal resolution.

Jess, D. B.; Mathioudakis, M.; Christian, D. J.; Keenan, F. P.; Ryans, R. S. I.; Crockett, P. J.

2010-02-01

223

Development Status of Multiangle SpectroPolarimetric Imager (MSPI) Prototype Cameras  

Microsoft Academic Search

We have been developing the Multiangle SpectroPolarimetric Imager (MSPI) as a candidate for the multi- directional, multi-wavelength, polarimetric imager identified by Earth Sciences Decadal Survey as one component of the Aerosol-Cloud-Ecosystem (ACE) mission. MSPI is conceptually similar to the Terra Multi- angle Imaging SpectroRadiometer (MISR), but contains a new camera design that widens the spectral range, increases the swath width,

D. J. Diner; A. Davis; S. Geier; B. Hancock; N. Raouf; C. Wrigley; M. A. Bull; V. M. Jovanovic; B. E. Rheingans; G. Saghri; R. A. Chipman; A. Mahler; S. McClain

2008-01-01

224

Imaging from Compton cameras using detectors with no spatial resolution capability  

NASA Astrophysics Data System (ADS)

To mitigate image degradation due to the finite spatial resolution of detectors, a new theory is developed that allows Compton cameras to be comprised of detectors that have no spatial resolution at all. The results of a computer simulation indicate that the new theory can be used to produce reasonable images at least when noiseless simulated data is used. Camera designs that can exploit the new theory for use in areas such as medicine and homeland security are presented. Although the results presented here are promising, further effort is needed to establish their usefulness with real data.

Smith, Bruce

2012-10-01

225

Detecting Doctored Images Using Camera Response Normality and Consistency  

Microsoft Academic Search

The advance in image\\/video editing techniques has facil- itated people in synthesizing realistic images\\/videos that may hard to be distinguished from real ones by visual ex- amination. This poses a problem: how to differentiate real images\\/videos from doctored ones? This is a serious prob- lem because some legal issues may occur if there is no reli- able way for doctored

Zhouchen Lint; Rongrong Wang; Xiaoou Tang; Heung-yeung Shum

2005-01-01

226

Imaging performance of a multiwire proportional-chamber positron camera  

SciTech Connect

A new design - fully three-dimensional - Positron Camera is presented, made of six MultiWire Proportional Chamber modules arranged to form the lateral surface of a hexagonal prism. A true coincidence rate of 56000 c/s is expected with an equal accidental rate for a 400 ..mu..Ci activity uniformly distributed in a approx. 3 l water phantom. A detailed Monte Carlo program has been used to investigate the dependence of the spatial resolution on the geometrical and physical parameters. A spatial resolution of 4.8 mm FWHM has been obtained for a /sup 18/F point-like source in a 10 cm radius water phantom. The main properties of the limited angle reconstruction algorithms are described in relation to the proposed detector geometry.

Perez-Mandez, V.; Del Guerra, A.; Nelson, W.R.; Tam, K.C.

1982-08-01

227

The image pretreatment based on the FPGA inside digital CCD camera  

NASA Astrophysics Data System (ADS)

In a space project, a digital CCD camera which can image more clearly in the 1 Lux light environment has been asked to design . The CCD sensor ICX285AL produced by SONY Co.Ltd has been used in the CCD camera. The FPGA (Field Programmable Gate Array) chip XQR2V1000 has been used as a timing generator and a signal processor inside the CCD camera. But in the low-light environment, two kinds of random noise become apparent because of the improving of CCD camera's variable gain, one is dark current noise in the image background, the other is vertical transfer noise. The real time method for eliminating noise based on FPGA inside the CCD camera would be introduced. The causes and characteristics of the random noise have been analyzed. First, several ideas for eliminating dark current noise had been motioned; then they were emulated by VC++ in order to compare their speed and effect; Gauss filter has been chosen because of the filtering effect. The vertical transfer vertical noise has the character that the vertical noise points have regular ordinate in the image two-dimensional coordinates; and the performance of the noise is fixed, the gray value of the noise points is 16-20 less than the surrounding pixels. According to these characters, local median filter has been used to clear up the vertical noise. Finally, these algorithms had been transplanted into the FPGA chip inside the CCD camera. A large number of experiments had proved that the pretreatment has better real-time features. The pretreatment makes the digital CCD camera improve the signal-to-noise ratio of 3-5dB in the low-light environment.

Tian, Rui; Liu, Yan-Ying

2009-07-01

228

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

NASA Astrophysics Data System (ADS)

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.

Wang, Yan; He, Chuanjiang

2012-04-01

229

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

PubMed

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

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

2013-04-02

230

Real-time video surveillance system using omni-directional image sensor and controllable camera  

NASA Astrophysics Data System (ADS)

The present paper describes a new indoor surveillance system for detection of an accident, such as fall or fit, happened to an aged single person. This system uses two types of cameras. One of them is the omni-directional image sensor for the tracking of the person"s position and detection of fall, and another is the controllable camera for capturing the detail of the person"s condition. The system detects points of the person"s head in images captured by some omni-directional image sensors, firstly. Then, a position of the person"s head in a room is computed from the points of person"s head in the images. When the person stops, the system classifies the person's pose into standing, sitting or lying according to the person's height. Then, the system judges that the accident has happened or not from the person"s pose, position and action. We made a prototype system with three omni-directional image sensors and a controllable camera. Then, we set the system in our laboratory"s room and experimented with the system. The implemented system detected the person"s position with the frame rate of 6 fps. In experiments, the error of position detection was 18 cm on the average. The error didn"t give serious influence to the control of the controllable camera. The error of height estimation was 6.9 cm. The conditions played by subjects were distinguished correctly.

Doi, Motonori; Aoki, Yutaro

2003-04-01

231

In vitro near-infrared imaging of occlusal dental caries using germanium enhanced CMOS camera  

PubMed Central

The high transparency of dental enamel in the near-infrared (NIR) at 1310-nm can be exploited for imaging dental caries without the use of ionizing radiation. The objective of this study was to determine whether the lesion contrast derived from NIR transillumination can be used to estimate lesion severity. Another aim was to compare the performance of a new Ge enhanced complementary metal-oxide-semiconductor (CMOS) based NIR imaging camera with the InGaAs focal plane array (FPA). Extracted human teeth (n=52) with natural occlusal caries were imaged with both cameras at 1310-nm and the image contrast between sound and carious regions was calculated. After NIR imaging, teeth were sectioned and examined using more established methods, namely polarized light microscopy (PLM) and transverse microradiography (TMR) to calculate lesion severity. Lesions were then classified into 4 categories according to the lesion severity. Lesion contrast increased significantly with lesion severity for both cameras (p<0.05). The Ge enhanced CMOS camera equipped with the larger array and smaller pixels yielded higher contrast values compared with the smaller InGaAs FPA (p<0.01). Results demonstrate that NIR lesion contrast can be used to estimate lesion severity.

Lee, Chulsung; Darling, Cynthia L.; Fried, Daniel

2011-01-01

232

640x512 InGaAs focal plane array camera for visible and SWIR imaging  

NASA Astrophysics Data System (ADS)

We report on our 640x512 pixel InGaAs/InP focal plane array camera for visible and short-wavelength infrared imaging. For this camera, we have fabricated a 640x512 element substrate-removed backside-illuminated InGaAs/InP photodiode array (PDA) with a 25 mm pixel pitch. The PDA is indium bump bonded to a silicon read out integrated circuit. Removing the InP substrate from the focal plane array allows visible wavelengths, which would otherwise be absorbed by the InP substrate due to its 920 nm wavelength cut-off, to reach the pixels' active region. The quantum efficiency is approximately 15% at 500 nm, 70% at 850 nm, 85% at 1310 nm, and 80% at 1550 nm. Features incorporated into this video-rate, 14-bit output camera include external triggering, windowing, individual pixel correction, 8 operational settings of gain and exposure time, and gamma correction. The readout circuit uses a gate-modulated pixel for high sensitivity imaging over a wide illumination range. This camera is useable for visible imaging as well as imaging eye-safe lasers and is of particular interest seeing laser designators and night vision as well as hyperspectral imaging.

Martin, Tara; Brubaker, Robert; Dixon, Peter; Gagliardi, Mari-Anne; Sudol, Tom

2005-05-01

233

High depth of field microscopic imaging using an interferometric camera.  

PubMed

We describe the design of a microscope combining rotational shear interferometer (RSI)-based coherence imaging with an objective lens to simultaneously obtain high numerical aperture and high depth of field imaging. We present experimental results showing the operation of this instrument. PMID:19421251

Potuluri, P; Fetterman, M; Brady, D

2001-05-21

234

High depth of field microscopic imaging using an interferometric camera  

NASA Astrophysics Data System (ADS)

We describe the design of a microscope combining rotational shear interferometer (RSI)-based coherence imaging with an objective lens to simultaneously obtain high numerical aperture and high depth of field imaging. We present experimental results showing the operation of this instrument.

Potuluri, P.; Fetterman, Matthew R.; Brady, David J.

2001-05-01

235

CMOS image sensor camera with focal plane edge detection  

Microsoft Academic Search

We present a simple, yet robust, VLSI implementation of sampled-method edge detection. Our technique adopts the well-known correlated double sampling (CDS), usually used for fixed pattern noise (FPN) reduction, to perform a sampled differentiation of the captured image to detect visual edges. This circuit is usually an integral part of most CMOS image sensors; therefore no additional area is required

Muahel Tabet; Richard Hornsey

2001-01-01

236

Robust Person Detection using Far Infrared Camera for Image Fusion  

Microsoft Academic Search

In this paper we present a robust method for person detection using far infrared images. To extract initial nominated head regions, thresholding and morphological operations are applied using intensity information. Among these regions, some of wrongly extracted regions are removed using the pattern of person head based on the local maximums of Sobel edge image. After the head regions are

Thi Thi Zin; Hideya Takahashi; Hiromitsu Hama

2007-01-01

237

Driving micro-optical imaging systems towards miniature camera applications  

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

238

Driving micro-optical imaging systems towards miniature camera applications  

Microsoft Academic Search

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

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

2010-01-01

239

N-band observations of comet Austin 1989cl: first images with the CIOmu camera  

NASA Astrophysics Data System (ADS)

We report here on the first observations obtained with the mid-infrared camera C1O?, mounted on the Canada-France-Hawaii Telescope in May 90. The main originality of this camera relies on its LETI/LIR detector array, whose large well capacity (>107 electrons) made easy broad-band imaging observations over the entire atmospheric window (8-13 ?m). As an illustration of the camera capabilities, we present high-angular resolution (0.7" pxl-1) N-band images of comet Austin. At the time of the observations (1990 May 6.6 UT), the comet was located at 0.45 AU from the earth, so that we were able to measure the surface brightness profile over a range of distances from the nucleus (300-3000 km) not yet well studied.

Lagage, P. O.; Merlin, P.; Remy, S.; Sibille, F.

1993-08-01

240

First Light with RATIR: An Automated 6-band Optical/NIR Imaging Camera  

NASA Astrophysics Data System (ADS)

The Reionization and Transients InfraRed camera (RATIR) is a simultaneous optical/NIR multi-band imaging camera which is 100% time-dedicated to the followup of Gamma-ray Bursts. The camera is mounted on the 1.5-meter Johnson telescope of the Mexican Observatorio Astronomico Nacional on Sierra San Pedro Martir in Baja California. With rapid slew capability and autonomous interrupt capabilities, the system will image GRBs in 6 bands (i, r, Z, Y, J, and H) within minutes of receiving a satellite position, detecting optically faint afterglows in the NIR and quickly alerting the community to potential GRBs at high redshift (z>6-10). We report here on this Spring's first light observing campaign with RATIR. We summarize the instrumental characteristics, capabilities, and observing modes.

Butler, Nat; Klein, Chris; Fox, Ori; Lotkin, Gennadiy; Bloom, Josh; Prochaska, J. Xavier; Ramirez-Ruiz, Enrico; de Diego, José A.; Georgiev, Leonid; González, Jesús; Lee, William H.; Richer, Michael G.; Román, Carlos; Watson, Alan M.; Gehrels, Neil; Kutyrev, Alexander; Bernstein, Rebecca; Alvarez, Luis Carlos; Ceseña, Urania; Clark, David; Colorado, Enrique; Córdova, Antolín.; Farah, Alejandro; García, Benjamín.; Guisa, Gerardo; Herrera, Joel; Lazo, Francisco; López, Eduardo; Luna, Esteban; Martínez, Benjamín.; Murillo, Francisco; Murillo, José Manuel; Núñez, Juan Manuel; Pedrayes, M. Herlinda; Quirós, Fernando; Ochoa, José Luis; Sierra, Gerardo; Moseley, Harvey; Rapchun, David; Robinson, Frederick D.; Samuel, Mathew V.; Sparr, Leroy M.

2012-09-01

241

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

NASA Astrophysics Data System (ADS)

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.

Hsia, Shih-Chang; Tsai, Po-Shien

2011-04-01

242

Calibration method for multiview camera with coplanar and decentered image sensors  

NASA Astrophysics Data System (ADS)

Here, we focus on the calibration of a multiview shooting system designed for the production of three-dimensional content for auto-stereoscopic visualization. The particularities of this multiview camera are the coplanarity of the image sensors and the shift that each sensor represents with regard to the corresponding optical axis. For the calibration of such cameras, we propose an approach based on Faugéras and Toscani's calibration method, which herein is extended to a multiview camera with parallel and decentered image sensors. First, the geometrical model of the shooting system is presented along with some industrial prototypes based on a geometrical analysis. Next, the development of the proposed calibration method is described. Last, some simulation results are presented, and some final concluding remarks about this research are then given.

Ali-Bey, Mohamed; Moughamir, Saïd; Manamanni, Noureddine

2013-04-01

243

High-speed two-camera imaging pyrometer for mapping fireball temperatures.  

PubMed

A high-speed imaging pyrometer was developed to investigate the behavior of flames and explosive events. The instrument consists of two monochrome high-speed Phantom v7.3 m cameras made by Vision Research Inc. arranged so that one lens assembly collects light for both cameras. The cameras are filtered at 700 or 900 nm with a 10 nm bandpass. The high irradiance produced by blackbody emission combined with variable shutter time and f-stop produces properly exposed images. The wavelengths were chosen with the expected temperatures in mind, and also to avoid any molecular or atomic gas phase emission. Temperatures measured using this pyrometer of exploded TNT charges are presented. PMID:22108886

Densmore, John M; Homan, Barrie E; Biss, Matthew M; McNesby, Kevin L

2011-11-20

244

Eyegaze Detection from Monocular Camera Image for Eyegaze Communication System  

NASA Astrophysics Data System (ADS)

An eyegaze interface is one of the key technologies as an input device in the ubiquitous-computing society. In particular, an eyegaze communication system is very important and useful for severely handicapped users such as quadriplegic patients. Most of the conventional eyegaze tracking algorithms require specific light sources, equipment and devices. In this study, a simple eyegaze detection algorithm is proposed using a single monocular video camera. The proposed algorithm works under the condition of fixed head pose, but slight movement of the face is accepted. In our system, we assume that all users have the same eyeball size based on physiological eyeball models. However, we succeed to calibrate the physiologic movement of the eyeball center depending on the gazing direction by approximating it as a change in the eyeball radius. In the gaze detection stage, the iris is extracted from a captured face frame by using the Hough transform. Then, the eyegaze angle is derived by calculating the Euclidean distance of the iris centers between the extracted frame and a reference frame captured in the calibration process. We apply our system to an eyegaze communication interface, and verified the performance through key typing experiments with a visual keyboard on display.

Ohtera, Ryo; Horiuchi, Takahiko; Kotera, Hiroaki

245

Two-dimensional sampling-image x-ray streak camera for ultrafast imaging of ICF plasmas  

NASA Astrophysics Data System (ADS)

Ultrafast two-dimensional (2D) x-ray imaging with a temporal resolution better than 10 ps is of great importance in diagnosing the final stages of the imploded core plasmas of ICF targets. Multi-imaging x-ray streak camera (MIXS)[1,2] has been one of such imaging technique. Recently, we have proposed another scheme, a 2D sampling-image x-ray streak camera method (2D-SIXS)[2]. In this scheme, a 2D image is sampled two-dimensionally with a set of sampling points distributed regularly over the whole image on a cathode plate of an x-ray streak camera. The sampled image is streaked, and then, reconstructed to form the time-resolved 2D images like movie pictures. In this paper, we report results of our proof-of-principle experiments of 2D-SIXS scheme performed at Gekko-XII glass laser system. A gold-coated spherical target was irradiated by three beams of Gekko-XII laser (527 nm). Streaked data of 2D-SIXS was obtained and a series of time-resolved 2D x-ray images were successfully reconstructed. [1] H. Shiraga, et al, Rev. Sci. Instrum. 66, 722 (1995), and references therein. [2] H. Shiraga, et al, Rev. Sci. Instrum. 68, 745 (1997).

Shiraga, H.; Nakasuji, M.; Heya, M.; Miyanaga, N.

1997-11-01

246

Two-dimensional sampling-image x-ray streak camera for ultrafast imaging of inertial confinement fusion plasmas  

NASA Astrophysics Data System (ADS)

Ultrafast two-dimensional (2D) x-ray imaging with a temporal resolution better than 10 ps is of great importance in diagnosing the final stages of the imploded core plasmas of inertial confinement fusion (ICF) targets. The multi-imaging x-ray streak camera (MIXS) has been one of such imaging techniques. Recently, we have proposed another scheme, a 2D sampling-image x-ray streak camera method (2D-SIXS). In this scheme, a 2D image is sampled two dimensionally with a set of sampling points distributed regularly over the whole image on a cathode plate of an x-ray streak camera. The sampled image is streaked, and then, reconstructed to form the time-resolved 2D images like movie pictures. In this article, we report results of our proof-of-principle experiments of 2D-SIXS scheme performed at Gekko-XII glass laser system. A gold-coated spherical target was irradiated by three beams (0.53 ?m) of Gekko-XII laser. Streaked data of 2D-SIXS were obtained and a series of time-resolved 2D x-ray images were successfully reconstructed. 2D-SIXS is suitable for very fast, short-lived, and small x-ray sources such as a hot spark in the ICF plasma as well as short-pulse-laser-produced plasmas.

Shiraga, H.; Nakasuji, M.; Heya, M.; Miyanaga, N.

1999-01-01

247

A survey of Martian dust devil activity using Mars Global Surveyor Mars Orbiter Camera images  

Microsoft Academic Search

A survey of dust devils using the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide- and narrow-angle (WA and NA) images has been undertaken. The survey comprises two parts: (1) sampling of nine broad regions from September 1997 to July 2001 and (2) a focused seasonal monitoring of variability in the Amazonis region, an active dust devil site, from

Jenny A. Fisher; Mark I. Richardson; Claire E. Newman; Mark A. Szwast; Chelsea Graf; Shabari Basu; Shawn P. Ewald; Anthony D. Toigo; R. John Wilson

2005-01-01

248

Future Planetary Surface Imager Development by the Beagle 2 Stereo Camera System Team  

NASA Astrophysics Data System (ADS)

The Stereo Camera System provided Beagle 2 with wide-angle multi-spectral stereo imaging (IFOV=0.043°). The SCS team plans to build on this design heritage to provide improved stereo capabilities to the Pasteur payload of the Aurora ExoMars rover.

Griffiths, A. D.; Coates, A. J.; Josset, J.-L.; Paar, G.

2004-03-01

249

Image processing module for high-speed thermal camera with cooled detector  

Microsoft Academic Search

Infrared cameras are used in various military applications for early detection and observation. In applications where very fast image acquisition is needed the so called cooled detectors are used. Cooled detectors are a kind of detectors that demands cryogenic cooling, but in return provide exceptional performance and temperature sensitivity with low integration times. These features predestinate cooled detectors for special

Grzegorz Bieszczad; Tomasz Sosnowski; Henryk Madura; Mariusz Kastek; Jaroslaw Barela

2011-01-01

250

Scatter correction in scintillation camera imaging of positron-emitting radionuclides  

Microsoft Academic Search

The use of Anger scintillation cameras for positron SPECT has become of interest recently due to their use with imaging 2-18F deoxyglucose. Due to the special crystal design (thin and wide), a significant amount of primary events will also be recorded in the Compton region of the energy spectra. Events recorded in a second Compton window (CW) can add information

M. Ljungberg; M. Danfelter; S.-E. Strand; M. A. King; B. A. Brill

1996-01-01

251

Positron emission imaging using acquired cone-surfaces from opposing compton cameras  

Microsoft Academic Search

The Compton camera, a method of electronic collimation, introduces angular resolution into a gamma-ray imaging system without the need of a collimating device. Compton kinematics are used to deduce the incident trajectory of the photon, resulting in a cone-surface of possible source locations. So far this type of system has been successfully employed only as a single photon detection device.

John E. Gillam; Toby E. Beveridge; Rob A. Lewis

2004-01-01

252

A laboratory use image plate camera for surface and interface structure analysis  

Microsoft Academic Search

We designed a new X-ray camera with an image plate (IP) detector so as to study surface and interface structures. It is made up of two goniometers with coaxial setup and a curved IP cassette that traverses up and down. The axis of rotation is vertical and perpendicular to the incident beam. The sample is mounted on one of the

Sae Shibata; Shuichi Doi; Isao Takahashi

2001-01-01

253

A CMOS CAMERA-BASED SYSTEM FOR NON-CONTACT PULSE OXIMETRY IMAGING  

Microsoft Academic Search

In this paper a non-contact pulse oximetry imaging system is described. The system utilises a CMOS digital camera and near infrared (NIR) light emitting diodes operating in a reflection mode to simultaneously capture photoplethysmograph (PPG) signals at two wavelengths. The Modified Beer- Lambert Law is used to extrapolate tissue oxygenation from the PPG signals. Attention is drawn to the system's

K. Humphreys; T. Ward; C. Markham

254

Camera Models and Optical Systems Used in Computer Graphics: Part II, Image-Based Techniques  

Microsoft Academic Search

In our companion paper (5), we described the optics under- lying camera models that have been used in computer graphics, and presented object space techniques for rendering with those models. In this paper, we survey image space techniques to simulate these models, and address topics including linear flltering, ray distribution bufiers, light flelds, and simulation techniques for interactive applications.

Brian A. Barsky; Daniel R. Horn; Stanley A. Klein; Jeffrey A. Pang; Meng Yu

2003-01-01

255

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

NASA Astrophysics Data System (ADS)

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 selected. One-to-one correspondence between visual filed and focal length of system is obtained and offers effective visual field information for the matching of imaging filed and illumination filed in range-gated 3-D imaging technology. On the basis of the experimental results, combined with the depth of field theory, the application of camera calibration in range-gated 3-D imaging technology is futher studied.

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

2013-09-01

256

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

USGS Publications Warehouse

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.

Light, D. L.

1996-01-01

257

Stereo-Digital Image Correlation (DIC) measurements with a single camera using a biprism  

NASA Astrophysics Data System (ADS)

In this paper we present and test a Digital Image Correlation (DIC)-based single camera pseudo-stereo system that uses a biprism in front of the camera objective to split the scene into two equivalent lateral stereo views in the two halves of the sensor. Such optical arrangement simplifies image pairs matching and, more importantly, makes possible a compact set-up suitable for miniaturization. To correct the image distortion caused by the refraction through the biprism, a proper optimization-based procedure is used to map the 3D reconstruction error function over the entire measurement volume. The inverse of the volumetric distortion function is then applied to the double-image of a spherical sample placed in an arbitrary position to evaluate the shape reconstruction accuracy. Finally, the capability of the proposed system to accurately track deformation in real-time is tested via an inflation test on a circular latex membrane.

Genovese, K.; Casaletto, L.; Rayas, J. A.; Flores, V.; Martinez, Amalia

2013-03-01

258

New tubeless nanosecond streak camera based on optical deflection and direct CCD imaging  

Microsoft Academic Search

A new optically deflected streaking camera with performance of nanosecond-range resolution, superior imaging quality, high signal detectability, and large format recording has been conceived and developed. Its construction is composed of an optomechanical deflector that deflects the line-shape image of spatial-distributed time-varying signals across the sensing surface of a cooled scientific two-dimensional CCD array with slow readout driving electronics, a

Ching C. Lai

1993-01-01

259

A new tubeless nanosecond streak camera based on optical deflection and direct CCD imaging  

Microsoft Academic Search

A new optically deflected streaking camera with performance of nanosecond-range resolution, superior imaging quality, high signal detectability, and large format recording has been conceived and developed. Its construction is composed of an optomechanical deflector that deflects the line-shape image of spatial-distributed time-varying signals across the sensing surface of a cooled scientific two-dimensional CCD array with slow readout driving electronics, a

C. C. Lai

1992-01-01

260

Use of image restoration and enhancement to improve x-ray pinhole camera resolution  

Microsoft Academic Search

Numerical image processing techniques are applied to the restoration of x-ray pinhole photographs of solid targets irradiated by intense relativistic electron beams. The numerical and analytic bases for image restoration are briefly described. An experimentally determined point-spread function for the pinhole camera is utilized to eliminate the effects of high-energy x-ray degradation of pinhole resolution. It is shown that penetration

A. J. Toepfer; H. B. Demuth

1977-01-01

261

High frame rate CCD cameras with fast optical shutters for military and medical imaging applications  

SciTech Connect

Los Alamos National Laboratory has designed and prototyped high-frame rate intensified/shuttered Charge-Coupled-Device (CCD) cameras capable of operating at kilohertz frame rates (non-interlaced mode) with optical shutters capable of acquiring nanosecond-to-microsecond exposures each frame. These cameras utilize an Interline Transfer CCD, Loral Fairchild CCD-222 with 244 {times} 380 pixels operated at pixel rates approaching 100 Mhz. Initial prototype designs demonstrated single-port serial readout rates exceeding 3.97 Kilohertz with greater than 51p/mm spatial resolution at shutter speeds as short as 5ns. Readout was achieved by using a truncated format of 128 {times} 128 pixels by partial masking of the CCD and then subclocking the array at approximately 65Mhz pixel rate. Shuttering was accomplished with a proximity focused microchannel plate (MCP) image intensifier (MCPII) that incorporated a high strip current MCP and a design modification for high-speed stripline gating geometry to provide both fast shuttering and high repetition rate capabilities. Later camera designs use a close-packed quadruple head geometry fabricated using an array of four separate CCDs (pseudo 4-port device). This design provides four video outputs with optional parallel or time-phased sequential readout modes. The quad head format was designed with flexibility for coupling to various image intensifier configurations, including individual intensifiers for each CCD imager, a single intensifier with fiber optic or lens/prism coupled fanout of the input image to be shared by the four CCD imagers or a large diameter phosphor screen of a gateable framing type intensifier for time sequential relaying of a complete new input image to each CCD imager. Camera designs and their potential use in ongoing military and medical time-resolved imaging applications are discussed.

King, N.S.P.; Albright, K.; Jaramillo, S.A.; McDonald, T.E.; Yates, G.J. [Los Alamos National Lab., NM (United States); Turko, B.T. [Lawrence Berkeley Lab., CA (United States)

1994-09-01

262

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

NASA Astrophysics Data System (ADS)

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.

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

263

Super-resolution image construction from high-speed camera sequences  

Microsoft Academic Search

Super-resolution is a very well-studied topic in image enhancement. However, traditional super-resolution techniques are limited by global motion assumption and the accuracy of displacement estimation. In this paper, we are interested in the problem of constructing super-resolution images from high-speed camera sequences with the presence of moving objects. The objective of our research is finding a suitable method for this

Hong-Thinh Nguyen; Viet-Dung Nguyen; Ha Vu Le

2010-01-01

264

Using vanishing points for camera calibration and coarse 3D reconstruction from a single image  

Microsoft Academic Search

  In this paper, we show how to calibrate a camera and to recover the geometry and the photometry (textures) of objects from\\u000a a single image. The aim of this work is to make it possible walkthrough and augment reality in a 3D model reconstructed from\\u000a a single image. The calibration step does not need any calibration target and makes only

E. Guillou; Daniel Meneveaux; Eric Maisel; Kadi Bouatouch

2000-01-01

265

Hologram synthesis of three-dimensional real objects using portable integral imaging camera.  

PubMed

We propose a portable hologram capture system based on integral imaging. An integral imaging camera with an integrated micro lens array captures spatio-angular light ray distribution of the three-dimensional scene under incoherent illumination. The captured light ray distribution is then processed to synthesize corresponding hologram. Experimental results show that the synthesized hologram is optically reconstructed successfully, demonstrating accommodation and motion parallax of the reconstructed three-dimensional scene. PMID:24104278

Lee, Sung-Keun; Hong, Sung-In; Kim, Yong-Soo; Lim, Hong-Gi; Jo, Na-Young; Park, Jae-Hyeung

2013-10-01

266

Goddard Space Flight Center astronomical Fabry–Pe´rot imaging camera  

Microsoft Academic Search

An astronomical camera is described which consists of a scanning Fabry–Pe´rot Interferometric (FPI) system coupled to a charge coupled detector (CCD) imaging system. The Fabry–Pe´rot etalon equipment consists of a commercially available Queensgate system. The CCD equipment is a commercially available Photometrics system employing one of the early developmental CCD chips of the Space Telescope Imaging Spectrograph (STIS) project. The

Larry W. Brown; Bruce E. Woodgate; Michael M. Ziegler; Peter J. Kenny; Ronald J. Oliversen

1994-01-01

267

CMOS image sensors: electronic camera-on-a-chip  

Microsoft Academic Search

CMOS active pixel sensors (APS) have performance competitive with charge-coupled device (CCD) technology, and offer advantages in on-chip functionality, system power reduction, cost, and miniaturization. This paper discusses the requirements for CMOS image sensors and their historical development, CMOS devices and circuits for pixels, analog signal chain, and on-chip analog-to-digital conversion are reviewed and discussed

Eric R. Fossum

1997-01-01

268

Innovative Camera and Image Processing System to Characterize Cryospheric Changes  

Microsoft Academic Search

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

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

2010-01-01

269

The trustworthy digital camera: Restoring credibility to the photographic image  

Microsoft Academic Search

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

Gary L. Friedman

1994-01-01

270

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

NASA Astrophysics Data System (ADS)

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.

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

2010-03-01

271

Infrared array camera (IRAC) design for the infrared imaging surveyor (IRIS)  

NASA Astrophysics Data System (ADS)

The revised baseline mission concept of the Space Infrared Telescope Facility (SIRTF) has assumed that the infrared array camera (IRAC), one of three focal plane instruments designed for SIRTF, will be removed from SIRTF and carried out collaboratively on the Japanese- launched Infrared Imaging Surveyor (IRIS) mission. The IRIS mission is an approved program scheduled for launch in 2001. In addition to IRAC, which will cover the 3 - 8 micron wavelength region, the proposed IRIS mission will also contain a mid-infrared array camera and a far-infrared scanner, consisting of three linear array detectors. We review the scientific requirements and design of IRAC required for incorporation into IRIS.

Fazio, Giovanni G.; Moseley, S. H.

1995-06-01

272

Performance characteristics of a small animal PET camera for molecular imaging  

NASA Astrophysics Data System (ADS)

The performance of a novel type of animal PET camera, the quad High-Density Avalanche Chamber (HIDAC) was assessed for a non-rotating 16-module system. Spatial resolution was 1.0 mm, and invariant within a standard deviation ?5%. Absolute sensitivity was 0.95%, and the scatter-background corrected sensitivity was 0.75%. The count rate capability was linear at typical activities used in animal imaging, with a 20% loss at 11.5 MBq. The camera demonstrates small regions of radiotracer uptake with excellent detail in the mouse.

Hastings, D. L.; Reader, A. J.; Julyan, P. J.; Zweit, J.; Jeavons, A. P.; Jones, T.

2007-04-01

273

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

SciTech Connect

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.

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

274

MONICA: A Compact, Portable Dual Gamma Camera System for Mouse Whole-Body Imaging  

PubMed Central

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/MBq (5.5 cps/?Ci); energy resolution (FWHM), 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-minute images acquired throughout the 168-hour 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.

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

2009-01-01

275

Implicit multiplane 3D camera calibration matrices for stereo image processing  

NASA Astrophysics Data System (ADS)

By implicit camera calibration, we mean the process of calibrating cameras without explicitly computing their physical parameters. We introduce a new implicit model based on a generalized mapping between an image plane and multiple, parallel calibration planes (usually between four to seven planes). This paper presents a method of computing a relationship between a point on a three-dimensional (3D) object and its corresponding two-dimensional (2D) coordinate in a camera image. This relationship is expanded to form a mapping of points in 3D space to points in image (camera) space and visa versa that requires only matrix multiplication operations. This paper presents the rationale behind the selection of the forms of four matrices and the algorithms to calculate the parameters for the matrices. Two of the matrices are used to map 3D points in object space to 2D points on the CCD camera image plane. The other two matrices are used to map 2D points on the image plane to points on user defined planes in 3D object space. The mappings include compensation for lens distortion and measurement errors. The number of parameters used can be increased, in a straight forward fashion, to calculate and use as many parameters as needed to obtain a user desired accuracy. Previous methods of camera calibration use a fixed number of parameters which can limit the obtainable accuracy and most require the solution of nonlinear equations. The procedure presented can be used to calibrate a single camera to make 2D measurements or calibrate stereo cameras to make 3D measurements. Positional accuracy of better than 3 parts in 10,000 have been achieved. The algorithms in this paper were developed and are implemented in MATLABR (registered trademark of The Math Works, Inc.). We have developed a system to analyze the path of optical fiber during high speed payout (unwinding) of optical fiber off a bobbin. This requires recording and analyzing high speed (5 microsecond exposure time), synchronous, stereo images of the optical fiber during payout. A 3D equation for the fiber at an instant in time is calculated from the corresponding pair of stereo images as follows. In each image, about 20 points along the 2D projection of the fiber are located. Each of these 'fiber points' in one image is mapped to its projection line in 3D space. Each projection line is mapped into another line in the second image. The intersection of each mapped projection line and a curve fitted to the fiber points of the second image (fiber projection in second image) is calculated. Each intersection point is mapped back to the 3D space. A 3D fiber coordinate is formed from the intersection, in 3D space, of a mapped intersection point with its corresponding projection line. The 3D equation for the fiber is computed from this ordered list of 3D coordinates. This process requires a method of accurately mapping 2D (image space) to 3D (object space) and visa versa.

McKee, James W.; Burgett, Sherrie J.

1997-12-01

276

System for evaluating the image quality of lenses and cameras  

NASA Astrophysics Data System (ADS)

This paper describes an automatic system for evaluating the photographic resolution from the information maximum. The technical characteristics of the system are presented, along with comparative data on errors in evaluating resolution by visual and informational methods. It is shown that the informational method of evaluating the image quality enhances the accuracy with which the resolution is determined, eliminates the consumption of photographic materials, and decreases the difficulty of the measurement process.

Barteneva, O. A.; Butyaikin, V. I.; Kalugin, D. E.; Reshetkina, I. V.

1994-02-01

277

MRi: high-speed dual-cameras hyperspectral imaging FTS  

Microsoft Academic Search

From scientific research to deployable operational solutions, Fourier-Transform Infrared (FT-IR) spectroradiometry is widely used for the development and enhancement of military and research applications. These techniques include targets IR signature characterization, development of advanced camouflage techniques, aircraft engine's plumes monitoring, meteorological sounding and atmospheric composition analysis such as detection and identification of chemical threats. Imaging FT-IR spectrometers have the capability

Florent Prel; Louis Moreau; Stéphane Lantagne; Claude Roy; Christian Vallières; Luc Lévesque

2011-01-01

278

The trustworthy digital camera: Restoring credibility to the photographic image  

NASA Astrophysics Data System (ADS)

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.

Friedman, Gary L.

1994-02-01

279

Mixel camera--a new push-broom camera concept for high spatial resolution keystone-free hyperspectral imaging.  

PubMed

Current high-resolution push-broom hyperspectral cameras introduce keystone errors to the captured data. Efforts to correct these errors in hardware severely limit the optical design, in particular with respect to light throughput and spatial resolution, while at the same time the residual keystone often remains large. The mixel camera solves this problem by combining a hardware component--an array of light mixing chambers--with a mathematical method that restores the hyperspectral data to its keystone-free form, based on the data that was recorded onto the sensor with large keystone. A Virtual Camera software, that was developed specifically for this purpose, was used to compare the performance of the mixel camera to traditional cameras that correct keystone in hardware. The mixel camera can collect at least four times more light than most current high-resolution hyperspectral cameras, and simulations have shown that the mixel camera will be photon-noise limited--even in bright light--with a significantly improved signal-to-noise ratio compared to traditional cameras. A prototype has been built and is being tested. PMID:23669962

Høye, Gudrun; Fridman, Andrei

2013-05-01

280

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

Microsoft Academic Search

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

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

2010-01-01

281

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

SciTech Connect

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 is gated off between exposures.

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

2011-05-11

282

A test-based comparison between technologies implemented in commercial cameras for high contrast imaging applications  

NASA Astrophysics Data System (ADS)

LAM is developing a high-contrast imaging testbeds for in-lab demonstration of new instrumental concepts requiring high contrast imaging: in particular, for solar and stellar coronagraphy applications. In such applications, a faint target has to be detected close to a very bright source. For these test-benches, a high-dynamic range detector is required to characterize and/or to determine the performance of a new concept. Beyond the capability to detect the target, an imaging detector has to be accurate, reliable and provide reproducible performances. In order to identify a commercial camera for the development of laboratory demonstrators working with high contrast scenes, we carried out a test campaign at the Laboratoire d’Astrophysique de Marseille (LAM) evaluating several cameras implementing different detector technologies. This paper presents the results of the test campaign, carried out at LAM, providing a quantitative comparison between the investigated technologies

Pancrazzi, M.; Landini, F.; Vives, S.; Escolle, C.; N'Diaye, M.; Focardi, M.; Guillon, C.

2012-07-01

283

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

NASA Astrophysics Data System (ADS)

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 131I, as predicted by theory. Potentially large gains in raw system sensitivity of a Compton camera similar in design to C-SPRINT could lead to substantial improvements in noise-equivalent performance of electronically-collimated cameras over mechanical systems, particularly in the energy range above 200 keV.

Leblanc, James Walter

284

Novel intraoperative near-infrared fluorescence camera system for optical image-guided cancer surgery.  

PubMed

Current methods of intraoperative tumor margin detection using palpation and visual inspection frequently result in incomplete resections, which is an important problem in surgical oncology. Therefore, real-time visualization of cancer cells is needed to increase the number of patients with a complete tumor resection. For this purpose, near-infrared fluorescence (NIRF) imaging is a promising technique. Here we describe a novel, handheld, intraoperative NIRF camera system equipped with a 690 nm laser; we validated its utility in detecting and guiding resection of cancer tissues in two syngeneic rat models. The camera system was calibrated using an activated cathepsin-sensing probe (ProSense, VisEn Medical, Woburn, MA). Fluorescence intensity was strongly correlated with increased activated-probe concentration (R2= .997). During the intraoperative experiments, a camera exposure time of 10 ms was used, which provided the optimal tumor to background ratio. Primary mammary tumors (n = 20 tumors) were successfully resected under direct fluorescence guidance. The tumor to background ratio was 2.34 using ProSense680 at 10 ms camera exposure time. The background fluorescence of abdominal organs, in particular liver and kidney, was high, thereby limiting the ability to detect peritoneal metastases with cathepsin-sensing probes in these regions. In conclusion, we demonstrated the technical performance of this new camera system and its intraoperative utility in guiding resection of tumors. PMID:20643025

Mieog, J Sven D; Vahrmeijer, Alexander L; Hutteman, Merlijn; van der Vorst, Joost R; Drijfhout van Hooff, Maurits; Dijkstra, Jouke; Kuppen, Peter J K; Keijzer, Rob; Kaijzel, Eric L; Que, Ivo; van de Velde, Cornelis J H; Löwik, Clemens W G M

2010-08-01

285

Miniature indium gallium arsenide short-wave infrared camera for unattended imaging applications  

NASA Astrophysics Data System (ADS)

Indium gallium arsenide (InGaAs) focal plane arrays and cameras have demonstrated significant potential in battlefield applications. Room temperature detectivities, D*, in excess of 1014 cm-(root)Hz/W have enabled night vision imaging under low light level conditions. The 0.9 micrometers to 1.7 micrometers wavelength band allows the use of eye- safe lasers for target designation and covert active illumination. We report here a miniature InGaAs camera designed for unattended ground sensor and robot-mounted applications. The camera is approximately the size of a D- cell battery, weighs less than 200 g. has a 320 X 240 pixel spatial resolution and maintains D* > 1014 cm- (root)Hz/W. The miniature camera is fully self contained. The only input is DC power (3.6 V). The camera has both analog (RS170) and 12-bit digital (LVDS) video outputs. It is intended as a demonstration vehicle for battlefield distributed robotic vision but will find use in other applications as an unattended sensor or rifle site.

Cohen, Marshall J.; O'Grady, Mathew T.; Vermaak, Jacobus S.; Groppe, Joseph V.; Olsen, Gregory H.

2000-07-01

286

Environmental applications of camera images calibrated by means of the Levenberg-Marquardt method  

NASA Astrophysics Data System (ADS)

Even though different authors have presented procedures for camera calibration in environmental video monitoring, improvements in the robustness and accuracy of the calibration procedure are always desired and in this work the Levenberg-Marquardt method is included in the camera calibration process for environmental video monitoring images as a way to improve the robustness of the camera calibration when a low number of control points is available without using laboratory measurements. The Pinhole model and the Levenberg-Marquardt method are briefly described and a four step camera calibration procedure using them is presented. This procedure allows users to use ground control points to estimate all the Pinhole model parameters, including the lens distortion parameters and its implementation results with laboratory data are compared with the results presented by other authors. The procedure is also tested with field data obtained with cameras directed toward the beaches of the city of Cartagena, Colombia. The results show that the procedure is robust enough to be used when just a low number of control points are available, even though a large number of GCP is recommended to obtain high accuracy.

Pérez Muñoz, J. C.; Ortiz Alarcón, C. A.; Osorio, A. F.; Mejía, C. E.; Medina, R.

2013-02-01

287

Passive millimeter-wave camera images: current and future  

NASA Astrophysics Data System (ADS)

Rapidly improving technology is transitioning current laboratory images into reality with fielded systems expected within two years. W-band radiometers have been shown to be effective in detecting metallic and nonmetallic weapons concealed under heavy garments in both outdoor and indoor situations. Systems that are in development will provide real-time display and weapon detection in controlled situations. The incorporation of technology improvements that have already been demonstrated will double the sensitivity and provide affordable systems with rapid scanning for general use. Lockheed Martin and Intelligent Machine Technology are working to build a demonstration system for the Department of Justice and the Air Force Research Laboratory that can be extended to take advantage of rapidly moving semiconductor improvements. Our current radiometer modules use a PIN switch for the Dicke calibration function followed by multiple low noise amplifier stages, a Schottky detector and a video amplifier. Sensitivity of such modules if primarily a function of the insertion loss and noise figure of the front end MMEC circuits. Processing improvements at Lockheed Martin and refined chip design will result in a 3-db improvement in the effective noise figure within the next year. Imaging is also greatly improved by achieving greater effective bandwidth and higher operating frequency. Whereas present modules operate from 80 to 90 G Hz, MMEC improvements will provide for operation up to 140G Hz with a doubling of the bandwidth in the near term. Receiver operation up to 540G Hz has also been demonstrated at other labs.

Mirth, Lee; Pergande, Al; Eden, Dayton D.; Chu, Lawrence Y.

1999-01-01

288

Engineering performance of IRIS2 infrared imaging camera and spectrograph  

NASA Astrophysics Data System (ADS)

IRIS2, the infrared imager and spectrograph for the Cassegrain focus of the Anglo Australian Telescope, has been in service since October 2001. IRIS2 incorporated many novel features, including multiple cryogenic multislit masks, a dual chambered vacuum vessel (the smaller chamber used to reduce thermal cycle time required to change sets of multislit masks), encoded cryogenic wheel drives with controlled backlash, a deflection compensating structure, and use of teflon impregnated hard anodizing for gear lubrication at low temperatures. Other noteworthy features were: swaged foil thermal link terminations, the pupil imager, the detector focus mechanism, phased getter cycling to prevent detector contamination, and a flow-through LN2 precooling system. The instrument control electronics was designed to allow accurate positioning of the internal mechanisms with minimal generation of heat. The detector controller was based on the AAO2 CCD controller, adapted for use on the HAWAII1 detector (1024 x 1024 pixels) and is achieving low noise and high performance. We describe features of the instrument design, the problems encountered and the development work required to bring them into operation, and their performance in service.

Churilov, Vladimir; Dawson, John; Smith, Greg A.; Waller, Lew; Whittard, John D.; Haynes, Roger; Lankshear, Allan; Ryder, Stuart D.; Tinney, Chris G.

2004-09-01

289

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

NASA Astrophysics Data System (ADS)

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.

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

2012-07-01

290

Strategies for registering range images from unknown camera positions  

NASA Astrophysics Data System (ADS)

We describe a project to construct a 3D numerical model of Michelangelo's Florentine Pieta to be used in a study of the sculpture. Here we focus on the registration of the range images used to construct the model. The major challenge was the range of length scales involved. A resolution of 1 mm or less required for the 2.25 m tall piece. To achieve this resolution, we could only acquire an area of 20 by 20 cm per scan. A total of approximately 700 images were required. Ideally, a tracker would be attached to the scanner to record position and pose. The use of a tracker was not possible in the field. Instead, we used a crude-to-fine approach to registering the meshes to one another. The crudest level consisted of pairwise manual registration, aided by texture maps containing laser dots that were projected onto the sculpture. This crude alignment was refined by an automatic registration of laser dot centers. In this phase, we found that consistency constraints on dot matches were essential to obtaining accurate results. The laser dot alignment was refined by an automatic registration of laser dot centers. In this phase, we found that consistency constraints on dot matches were essential to obtaining accurate results. The laser dot alignment was further refined using a variation of the ICP algorithm developed by Besl and McKay. In the application of ICP to global registration, we developed a method to avoid one class of local minima by finding a set of points, rather than the single point, that matches each candidate point.

Bernardini, Fausto; Rushmeier, Holly E.

2000-03-01

291

Skin hydration imaging using a long-wavelength near-infrared digital camera  

NASA Astrophysics Data System (ADS)

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.

Attas, Michael; Posthumus, Trevor; Schattka, Bernhard J.; Sowa, Michael G.; Mantsch, Henry H.; Zhang, Shuliang L.

2001-07-01

292

Design of a new Compton Camera by Monte Carlo method and assessment its important parameters affecting image quality  

Microsoft Academic Search

\\u000a In nuclear medicine imaging systems such as Gamma camera and SPECT, currently uses a mechanical collimator and a scintillation\\u000a detector to detect distribution of gamma emitter radiopharmaceuticals. The detection technique, however, suffers from spatial\\u000a resolution and sensitivity trade-off because of mechanical collimation. Compton camera principle is a suggested alternative\\u000a which avoids the mentioned trade-off. Compton camera consists of one scattering

A. Karimian; B. Jia; G. Raisali; F. Rahimi

293

Calibration and control of a robot arm using a range imaging camera  

NASA Astrophysics Data System (ADS)

Time of flight range imaging is an emerging technology that has numerous applications in machine vision. In this paper we cover the use of a commercial time of flight range imaging camera for calibrating a robotic arm. We do this by identifying retro-reflective targets attached to the arm, and centroiding on calibrated spatial data, which allows precise measurement of three dimensional target locations. The robotic arm is an inexpensive model that does not have positional feedback, so a series of movements are performed to calibrate the servos signals to the physical position of the arm. The calibration showed a good linear response between the control signal and servo angles. The calibration procedure also provided a transformation between the camera and arm coordinate systems. Inverse kinematic control was then used to position the arm. The range camera could also be used to identify objects in the scene. With the object location now known in the arm's coordinate system (transformed from the camera's coordinate system) the arm was able to move allowing it to grasp the object.

Kelly, Cameron B. D.; Dorrington, Adrian A.; Cree, Michael J.; Payne, Andrew D.

2010-02-01

294

High-resolution image digitizing through 12x3-bit RGB-filtered CCD camera  

NASA Astrophysics Data System (ADS)

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.

Cheng, Andrew Y.; Pau, C. Y.

1996-09-01

295

New design of a gamma camera detector with reduced edge effect for breast imaging  

NASA Astrophysics Data System (ADS)

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.

Yeon Hwang, Ji; Lee, Seung-Jae; Baek, Cheol-Ha; Hyun Kim, Kwang; Hyun Chung, Yong

2011-05-01

296

Passive millimeter-wave camera images: current and future  

NASA Astrophysics Data System (ADS)

Lockheed Martin and Intelligent Machine Technology are working to build a demonstration system for the Department of Justice and the Air Force Research Laboratory that can be extended to take advantage of rapidly moving semiconductor improvements. Our current radiometer modules use a PIN switch for the Dicke calibration function followed by multiple low noise amplifier stages, a Schottky detector and a video amplifier. Sensitivity of such modules is primarily a function of the insertion loss and noise figure of the front end MMIC circuits. Processing improvements at Lockheed Martin and refined chip design will result in a 3 dB improvement in the effective noise figure within the next year. Imaging is also greatly improved by achieving greater effective bandwidth and higher operating frequency. Whereas present modules operate from 80 to 90 GHz, MMIC improvements will provide for operation up to 140 GHz with a doubling of the bandwidth in the near term. Receiver operation up to 540 GHz has also been demonstrated at other labs.

Mirth, Lee; Pergande, Al; Eden, Dayton D.; Chu, Lawrence Y.

1999-07-01

297

High-speed multispectral three-dimensional imaging with a compound-eye camera TOMBO  

NASA Astrophysics Data System (ADS)

We propose a high-speed multispectral three-dimensional imaging system based on a compact and thin compound-eye camera called TOMBO. Wavelengths and times are assigned to the lenses in TOMBO. The time delays are introduced by the rolling shutter of CMOS image sensors, and wavelength decomposition is realized by attaching several kinds of wavelength filters to the lenses. A depth map is reproduced based on disparities in the unit images captured at the same timing. In reproducing the depth map, sum of sum of absolute differences (SSAD) is evaluated after average equalization to compare images for different wavelengths. A prototype of TOMBO is built with a SXGA monochrome CMOS image sensor with a rolling shutter, optical crosstalk barriers, a commercial 5x5-element microlens array, and commercial gelatin color filters. Enhancement of the frame rate and reproduction of a depth map and a 5-band deep-focus image are demonstrated.

Kagawa, Keiichiro; Fukata, Naoki; Tanida, Jun

2010-08-01

298

Cardiac cameras.  

PubMed

Cardiac imaging with radiotracers plays an important role in patient evaluation, and the development of suitable imaging instruments has been crucial. While initially performed with the rectilinear scanner that slowly transmitted, in a row-by-row fashion, cardiac count distributions onto various printing media, the Anger scintillation camera allowed electronic determination of tracer energies and of the distribution of radioactive counts in 2D space. Increased sophistication of cardiac cameras and development of powerful computers to analyze, display, and quantify data has been essential to making radionuclide cardiac imaging a key component of the cardiac work-up. Newer processing algorithms and solid state cameras, fundamentally different from the Anger camera, show promise to provide higher counting efficiency and resolution, leading to better image quality, more patient comfort and potentially lower radiation exposure. While the focus has been on myocardial perfusion imaging with single-photon emission computed tomography, increased use of positron emission tomography is broadening the field to include molecular imaging of the myocardium and of the coronary vasculature. Further advances may require integrating cardiac nuclear cameras with other imaging devices, ie, hybrid imaging cameras. The goal is to image the heart and its physiological processes as accurately as possible, to prevent and cure disease processes. PMID:21440695

Travin, Mark I

2011-05-01

299

Real time speed estimation of moving vehicles from side view images from an uncalibrated video camera.  

PubMed

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

Do?an, Sedat; Temiz, Mahir Serhan; Külür, Sitki

2010-05-11

300

Development of a high-speed camera system for neutron imaging at a pulsed neutron source  

NASA Astrophysics Data System (ADS)

A neutron energy resolved imaging system with a time-of-flight technique has been newly developed and installed at Japan Proton Accelerator Research Complex (J-PARC) with the aim to investigate more preciously and rapidly a spatial distribution of several elements and crystals in various kinds of materials or substances. A high-speed video camera (CMOS, 1300 k frame/s) equipped system allows to obtain TOF images consecutively resolved into narrow energy ranges with a single pulsed neutrons while conventional CCD camera imaging system could obtain only one TOF image in an arbitral neutron energy region in the pulsed neutron energy region from 0.01 eV to a few keV. Qualities of the images obtained with the system, such as spatial resolution (defined by modulation transfer function, 0.8 line-pairs/mm at En˜0.01 eV), dependence of the brightness on the neutron energy and measurement errors (˜2%) of the system were examined experimentally and evaluated by comparison with those of conventional imaging system. The results obtained in the experiments show that the system can visualize the neutron energy resolved images within a small error even at high speed.

Segawa, M.; Kai, T.; Sakai, T.; Ooi, M.; Kureta, M.

2013-01-01

301

Image recovery from data acquired with a charge-coupled-device camera.  

NASA Astrophysics Data System (ADS)

A model for data acquired with the use of a charge-coupled-device camera is given and is then used for developing a new iterative method for restoring intensities of objects observed with such a camera. The model includes the effects of point spread, photoconversion noise, readout noise, nonuniform flat-field response, nonuniform spectral response, and extraneous charge carriers resulting from bias, dark current, and both internal and external background radiation. An iterative algorithm is identified that produces a sequence of estimates converging toward a constrained maximum-likelihood estimate of the intensity distribution of an imaged object. An example is given for restoring images from data acquired with the use of the Hubble Space Telescope.

Snyder, D. L.; Hammoud, A. M.; White, R. L.

1993-05-01

302

Contrast Control of Far-infrared Camera by Varying the Image Sensor Temperature  

NASA Astrophysics Data System (ADS)

A far-infrared camera is thought to be well suited to detection of pedestrians at night. However, around sunset time during the summer, because the temperature difference between pedestrians and background objects becomes small, it is difficult to distinguish pedestrians with the far-infrared camera. To solve this problem, we propose a new contrast control method that is varying of the image sensor temperature. By means of increasing the image sensor temperature from 25 to 50°C the contrast between road and clothes, and sky and clothes increased about 1.54 and 1.64 times, respectively. The contrast between sky and skin increased about 1.55 times, but that between the road and skin did not increase. Because the emissivities of these objects were similar. The contrast control method is effective to detect objects with relatively large differences in emissivity at just about the same temperature.

Fujitsuka, Norio; Naganawa, Hiroshi

303

Clinical Imaging Characteristics of the Positron Emission Mammography Camera: PEM Flex Solo II  

PubMed Central

We evaluated a commercial positron emission mammography (PEM) camera, the PEM Flex Solo II. This system comprises two 6 × 16.4 cm detectors that scan together covering up to a 24 × 16.4 cm field of view (FOV). There are no specific standards for testing this detector configuration. We performed several tests important to breast imaging, and we propose tests that should be included in standardized testing of PEM systems. Methods: We measured spatial resolution, uniformity, counting-rate linearity, recovery coefficients, and quantification accuracy using the system's software. Image linearity and coefficient of variation at the edge of the FOV were also characterized. Anecdotal examples of clinical patient data are presented. Results: The spatial resolution was 2.4 mm in full width at half maximum for image planes parallel to the detector faces. The background variability was approximately 5%, and quantification accuracy and recovery coefficients varied within the FOV. Positioning linearity began at approximately 13 mm from the edge of the detector housing. The coefficient of variation was significantly higher close to the edge of the FOV because of limited sensitivity in these image planes. Conclusion: A reconstructed spatial resolution of 2.4 mm represented a significant improvement over conventional whole-body PET scanners and should reduce the lower threshold on lesion size and tracer uptake for detection in the breast. Limited-angle tomography and a lack of data corrections result in spatially variable quantitative results. PEM acquisition geometry limits sampling statistics at the chest-wall edge of the camera, resulting in high variance in that portion of the image. Example patient images demonstrate that lesions can be detected at the chest-wall edge despite variance artifacts, and fine structure is visualized routinely throughout the FOV in the focal plane. The PEM Flex camera should enable the functional imaging of breast cancer earlier in the disease process than whole-body PET.

MacDonald, Lawrence; Edwards, John; Lewellen, Thomas; Haseley, David; Rogers, James; Kinahan, Paul

2010-01-01

304

Venus cloud top winds from tracking UV features in Venus Monitoring Camera images  

Microsoft Academic Search

To date dynamical observations of the Venus clouds have delivered mainly either only short-term or long-term averaged results. With the Venus Monitoring Camera (VMC) it finally became possible to investigate the global dynamics with a relatively high resolution in space and time on a long-term basis. Our findings from manual cloud feature wind tracking in VMC UV image sequences so

R. Moissl; I. Khatuntsev; S. S. Limaye; D. V. Titov; W. J. Markiewicz; N. I. Ignatiev; T. Roatsch; K.-D. Matz; R. Jaumann; M. Almeida; G. Portyankina; T. Behnke; S. F. Hviid

2009-01-01

305

A Real-time Wide field of View Passive Millimeter-wave Imaging Camera  

Microsoft Academic Search

With the current upsurge in domestic terrorism, suicide bombings and the like, there is an increased interest in high technology sensors that can provide true stand-off detection of concealed articles such as guns and, in particular, explosives in both controlled and uncontrolled areas. The camera discussed in this paper is based upon passive millimeter-wave imaging (75.5-93.5 GHz) and is intrinsically

Stuart Clark; Chris Martin; Peter J. Costianes; Vladimir Kolinko; John Lovberg

2003-01-01

306

Demonstration of three-dimensional imaging with a germanium Compton camera  

Microsoft Academic Search

A proof-of-concept experiment was performed to demonstrate the three-dimensional imaging capabilities of an all-germanium Compton camera for near-field sources. Eight high purity germanium (HPGe) coaxial detectors were configured in two planes of four detectors each. The data acquisition system was assembled from available hardware and off-the-shelf electronics using standard NIM and CAMAC modules. Sixteen-parameter data were recorded event-by-event for later

J. E. McKisson; P. S. Haskins; G. W. Phillips; S. E. King; R. A. August; R. B. Piercey; R. C. Mania

1994-01-01

307

A high-speed, pressurised multi-wire gamma camera for dynamic imaging in nuclear medicine  

Microsoft Academic Search

High count rate detectors are of particular interest in nuclear medicine as they permit lower radiation doses to be received by the patient and allow dynamic images of high statistical quality to be obtained.We have developed a high-speed gamma camera based on a multi-wire proportional chamber. The chamber is filled with a xenon gas mixture and has been operated at

A. Barr; L. Bonaldi; G. Carugno; G. Charpak; D. Iannuzzi; M. Nicoletto; A. Pepato; S. Ventura

2002-01-01

308

Observations of Mars and its satellites by the Mars Imaging Camera (MIC) on Planet-B  

Microsoft Academic Search

We present the specifications of the Mars Imaging Camera (MIC) on the Planet-B spin-stabilized spacecraft, and key scientific objectives of MIC observations. A non-sun-synchronous orbit of Planet-B with a large eccentricity of about 0.87 around Mars provides the opportunities (1) to observe the same region of Mars at various times of day and various solar phase angles with spatial resolution

Tadashi Mukai; Tokuhide Akabane; Tatsuaki Hashimoto; Hiroshi Ishimoto; Sho Sasaki; A. Inada; Anthony Toigo; Masato Nakamura; Yutaka Abe; Kei Kurita; Takeshi Imamura

1998-01-01

309

CCD-Camera images of BEST-TWO and processing results  

NASA Astrophysics Data System (ADS)

A survey is presented of the 'still video' pictures that have been recorded with 3 CCD-cameras during the BEST-TWO trial in Mourmelon, France. The composition of and selection for two databases is described, and the results of processing with the FELimage processing algorithm are given. A statistical analysis of these processing results is carried out and described. For each scenario, one or more examples of processed images are given.

Boden, J. A.; Deutekom, M.; Wilmink, M. J.

1993-04-01

310

Use of a compact pixellated gamma camera for small animal pinhole SPECT imaging  

Microsoft Academic Search

Objectives  Pinhole SPECT which permitsin vivo high resolution 3D imaging of physiological functions in small animals facilitates objective assessment of pharmaceutical\\u000a development and regenerative therapy in pre-clinical trials. For handiness and mobility, the miniature size of the SPECT system\\u000a is useful. We developed a small animal SPECT system based on a compact high-resolution gamma camera fitted to a pinhole collimator\\u000a and

Tsutomu Zeniya; Hiroshi Watabe; Toshiyuki Aoi; Kyeong Min Kim; Noboru Teramoto; Takeshi Takeno; Yoichiro Ohta; Takuya Hayashi; Hiroyuki Mashino; Toshihiro Ota; Seiichi Yamamoto; Hidehiro Iida

2006-01-01

311

A highly reliable and budget-friendly Peltier-cooled camera for biological fluorescence imaging microscopy.  

PubMed

The SAC8.5, a low-cost Peltier-cooled black and white 8-bit CCD camera for astronomy, was evaluated for its use in imaging microscopy. Two camera-microscope configurations were used: an epifluorescence microscope (Nikon Eclipse TE2000-U) and a bottom port laser scanning confocal microscope system (Zeiss LSCM 510 META). Main advantages of the CCD camera over the currently used photomultiplier detection in the scanning setup are fast image capturing, stable background, an improved signal-to-noise ratio and good linearity. Based on DAPI-labelled Chinese Hamster Ovarian cells, the signal-to-noise ratio was estimated to be 4 times higher with respect to the currently used confocal photomultiplier detector. A linear relationship between the fluorescence signal and the FITC-inulin concentrations ranging from 0.05 to 1.8 mg mL(-1) could be established. With the SAC8.5 CCD camera and using DAPI, calcein-AM and propidium iodide we could also distinguish between viable, apoptotic and necrotic cells: exposure to CdCl(2) caused necrosis in A6 cells. Additional examples include the observation of wire-like mitochondrial networks in Mito Tracker Green-loaded Madin-Darby canine kidney cells. Furthermore, it is straightforward to interface the SAC8.5 with automated shutters to prevent rapid fluorophore photobleaching via easy to use astrovideo software. In this study, we demonstrate that the SAC8.5 black and white CCD camera is an easy-to-implement and cost-conscious addition to quantitative fluorescence microfluorimetry on living tissues and is suitable for teaching laboratories. PMID:18045321

Jolling, Koen; Vandeven, Martin; Van den Eynden, Jimmy; Ameloot, Marcel; Van Kerkhove, Emmy

2007-12-01

312

Development Status of Multiangle SpectroPolarimetric Imager (MSPI) Prototype Cameras  

NASA Astrophysics Data System (ADS)

We have been developing the Multiangle SpectroPolarimetric Imager (MSPI) as a candidate for the multi- directional, multi-wavelength, polarimetric imager identified by Earth Sciences Decadal Survey as one component of the Aerosol-Cloud-Ecosystem (ACE) mission. MSPI is conceptually similar to the Terra Multi- angle Imaging SpectroRadiometer (MISR), but contains a new camera design that widens the spectral range, increases the swath width, and adds high-accuracy polarimetry in selected spectral bands to supplement intensity measurements with additional constraints on aerosol microphysical properties. To provide low degree of polarization uncertainty (0.5%) and high polarimetric sensitivity, MSPI includes a novel dual- photoelastic modulator system that generates a temporally modulated signal from which the linear Stokes vector components can be synchronously recovered. The first prototype MSPI camera is a field-deployable system ("GroundMSPI") operating at 660 nm. A second prototype will contain 8 spectral bands from 355 to 935 nm and is aimed at future deployment aboard the NASA ER-2 aircraft ("AirMSPI"). Along with the instrument hardware, a ground data processing system for generating calibrated, georectified imagery is being built. Initial experimental results from the assembled GroundMSPI camera will be presented.

Diner, D. J.; Davis, A.; Geier, S.; Hancock, B.; Raouf, N.; Wrigley, C.; Bull, M. A.; Jovanovic, V. M.; Rheingans, B. E.; Saghri, G.; Chipman, R. A.; Mahler, A.; McClain, S.

2008-12-01

313

COMPACT CdZnTe-BASED GAMMA CAMERA FOR PROSTATE CANCER IMAGING  

SciTech Connect

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 have been completed. The results show better than 6-mm resolution at a distance of 1 cm. Details of the test results are discussed in this paper.

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

314

Compact CdZnTe-based gamma camera for prostate cancer imaging  

NASA Astrophysics Data System (ADS)

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 have been completed. The results show better than 6-mm resolution at a distance of 1 cm. Details of the test results are discussed in this paper.

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

315

Noise estimation from a single image taken by specific digital camera using a priori information  

NASA Astrophysics Data System (ADS)

It is important to estimate the noise of digital image quantitatively and efficiently for many applications such as noise removal, compression, feature extraction, pattern recognition, and also image quality assessment. For these applications, it is necessary to estimate the noise accurately from a single image. Ce et al proposed a method to use a Bayesian MAP for the estimation of noise. In this method, the noise level function (NLF) which is standard deviation of intensity of image was estimated from the input image itself. Many NLFs were generated by using computer simulation to construct a priori information for Bayesian MAP. This a priori information was effective for the accurate noise estimation but not enough for practical applications since the a priori information didn't reflect the variable characteristics of the individual camera depending on the exposure and shutter speed. In this paper, therefore, we propose a new method to construct a priori information for specific camera in order to improve accuracy of noise estimation. To construct a priori information of noise, the NLFs were measured and calculated from the images captured under various conditions. We compared the accuracy of noise estimation between proposed method and Ce's model. The results showed that our model improved the accuracy of noise estimation.

Ito, Hitomi; Kamimura, Kenji; Tsumura, Norimichi; Nakaguchi, Toshiya; Motomura, Hideto; Miyake, Yoichi

2008-01-01

316

Imaging microscopic structures in pathological retinas using a flood-illumination adaptive optics retinal camera  

NASA Astrophysics Data System (ADS)

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.

Viard, Clément; Nakashima, Kiyoko; Lamory, Barbara; Pâques, Michel; Levecq, Xavier; Château, Nicolas

2011-02-01

317

Diffuse reflection imaging of sub-epidermal tissue haematocrit using a simple RGB camera  

NASA Astrophysics Data System (ADS)

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).

Leahy, Martin J.; O'Doherty, Jim; McNamara, Paul; Henricson, Joakim; Nilsson, Gert E.; Anderson, Chris; Sjoberg, Folke

2007-06-01

318

Development of a high-speed CT imaging system using EMCCD camera  

NASA Astrophysics Data System (ADS)

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 ?m resolution, compared to several minutes at 160 ?m resolution needed for the best current systems.

Thacker, Samta C.; Yang, Kai; Packard, Nathan; Gaysinskiy, Valeriy; Burkett, George; Miller, Stuart; Boone, John M.; Nagarkar, Vivek

2009-02-01

319

Real-time lock-in imaging by a newly developed high-speed image-processing charge coupled device video camera  

NASA Astrophysics Data System (ADS)

Real-time lock-in imaging with high-frequency modulation (up to 16 kHz) was successfully performed at high spatial resolution (640×480 pixels) using a newly developed high-speed image-processing charge coupled device (CCD) video camera. To achieve high-resolution lock-in imaging, the high-speed image-processing CCD video camera incorporates a high-definition TV image sensor that uses a high-definition frame-interline-transfer (FIT) CCD architecture. A novel FIT-CCD driving method, in which vertical CCD shift registers are utilized as a temporary frame memory, enables lock-in imaging at a modulation frequency in excess of the video frame rate (30 Hz). Furthermore, since the high-speed image-processing CCD video camera has a function for subtracting images taken with high-frequency modulation, a lock-in image with no background contrast can be observed in real time. The phase detection function for lock-in imaging, when coupled with real-time image processing using the high-speed image-processing CCD video camera, makes it possible to dynamically observe the phase distribution in a two-dimensional area. As a demonstration of the real-time lock-in imaging, the wave pattern that appears on the surface of water was successfully visualized by a real-time lock-in imaging system that uses the high-speed image-processing CCD video camera.

Nishikata, Kentarou; Kimura, Yoshihide; Takai, Yoshizo; Ikuta, Takashi; Shimizu, Ryuichi

2003-03-01

320

Electron-tracking Compton gamma-ray camera for small animal and phantom imaging  

NASA Astrophysics Data System (ADS)

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.

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

321

The measurement of astronomical parallaxes with CCD imaging cameras on small telescopes  

SciTech Connect

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.

Ratcliff, S.J. (Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States)); Balonek, T.J. (Department of Physics and Astronomy, Colgate University, 13 Oak Dr., Hamilton, New York 13346 (United States)); Marschall, L.A. (Department of Physics, Gettysburg College, Gettysburg, Pennsylvania 17325 (United States)); DuPuy, D.L. (Department of Physics and Astronomy, Virginia Military Institute, Lexington, Virginia 24450 (United States)); Pennypacker, C.R. (Space Sciences Laboratory, University of California, Berkeley, California 94720 (United States)); Verma, R. (Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States)); Alexov, A. (Department of Astronomy, Wesleyan University, Middletown, Connecticut 06457 (United States)); Bonney, V. (Space Sciences Laboratory, University of California, Berkeley, California 94720 (United States))

1993-03-01

322

Flame colour characterization in the visible and infrared spectrum using a digital camera and image processing  

NASA Astrophysics Data System (ADS)

An attempt has been made to characterize the colour spectrum of methane flame under various burning conditions using RGB and HSV colour models instead of resolving the real physical spectrum. The results demonstrate that each type of flame has its own characteristic distribution in both the RGB and HSV space. It has also been observed that the averaged B and G values in the RGB model represent well the CH* and C*2 emission of methane premixed flame. Theses features may be utilized for flame measurement and monitoring. The great advantage of using a conventional camera for monitoring flame properties based on the colour spectrum is that it is readily available, easy to interface with a computer, cost effective and has certain spatial resolution. Furthermore, it has been demonstrated that a conventional digital camera is able to image flame not only in the visible spectrum but also in the infrared. This feature is useful in avoiding the problem of image saturation typically encountered in capturing the very bright sooty flames. As a result, further digital imaging processing and quantitative information extraction is possible. It has been identified that an infrared image also has its own distribution in both the RGB and HSV colour space in comparison with a flame image in the visible spectrum.

Huang, Hua-Wei; Zhang, Yang

2008-08-01

323

A real-time image-to-panorama registration approach for background subtraction using pan-tilt-cameras  

Microsoft Academic Search

While for static cameras several background subtraction approaches have been developed in the past, for non-static pan\\/tilt cameras efficient and robust motion detection is still a challenging task. Known approaches use image-to-image registration methods to generate a panorama background model of the scene, which spans a joint pixel coordinate system for later background estimation and subtraction. However, for a real-time

Eduardo Monari; Thomas Pollok

2011-01-01

324

The computation of cloud base height from paired whole-sky imaging cameras  

SciTech Connect

A major goal for global change studies is to improve the accuracy of general circulation models (GCMs) capable of predicting the timing and magnitude of greenhouse gas-induced global warming. Research has shown that cloud radiative feedback is the single most important effect determining the magnitude of possible climate responses to human activity. Of particular value to reducing the uncertainties associated with cloud-radiation interactions is the measurement of cloud base height (CBH), both because it is a dominant factor in determining the infrared radiative properties of clouds with respect to the earth`s surface and lower atmosphere and because CBHs are essential to measuring cloud cover fraction. We have developed a novel approach to the extraction of cloud base height from pairs of whole sky imaging (WSI) cameras. The core problem is to spatially register cloud fields from widely separated WSI cameras; this complete, triangulation provides the CBH measurements. The wide camera separation (necessary to cover the desired observation area) and the self-similarity of clouds defeats all standard matching algorithms when applied to static views of the sky. To address this, our approach is based on optical flow methods that exploit the fact that modern WSIs provide sequences of images. We will describe the algorithm and present its performance as evaluated both on real data validated by ceilometer measurements and on a variety of simulated cases.

Allmen, M.C.; Kegelmeyer, W.P. Jr.

1994-03-01

325

Algorithm design for automated transportation photo enforcement camera image and video quality diagnostic check modules  

NASA Astrophysics Data System (ADS)

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.

Raghavan, Ajay; Saha, Bhaskar

2013-03-01

326

The use of vision-based image quality metrics to predict low-light performance of camera phones  

Microsoft Academic Search

Small digital camera modules such as those in mobile phones have become ubiquitous. Their low-light performance is of utmost importance since a high percentage of images are made under low lighting conditions where image quality failure may occur due to blur, noise, and\\/or underexposure. These modes of image degradation are not mutually exclusive: they share common roots in the physics

B. Hultgren; D. Hertel

2010-01-01

327

In situ X-ray beam imaging using an off-axis magnifying coded aperture camera system  

PubMed Central

An imaging model and an image reconstruction algorithm for a transparent X-ray beam imaging and position measuring instrument are presented. The instrument relies on a coded aperture camera to record magnified images of the footprint of the incident beam on a thin foil placed in the beam at an oblique angle. The imaging model represents the instrument as a linear system whose impulse response takes into account the image blur owing to the finite thickness of the foil, the shape and size of camera’s aperture and detector’s point-spread function. The image reconstruction algorithm first removes the image blur using the modelled impulse response function and then corrects for geometrical distortions caused by the foil tilt. The performance of the image reconstruction algorithm was tested in experiments at synchrotron radiation beamlines. The results show that the proposed imaging system produces images of the X-ray beam cross section with a quality comparable with images obtained using X-ray cameras that are exposed to the direct beam.

Kachatkou, Anton; Kyele, Nicholas; Scott, Peter; van Silfhout, Roelof

2013-01-01

328

Megapixel imaging camera for expanded H{sup {minus}} beam measurements  

SciTech Connect

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.

Simmons, J.E.; Lillberg, J.W.; McKee, R.J.; Slice, R.W.; Torrez, J.H. [Los Alamos National Lab., NM (United States); McCurnin, T.W.; Sanchez, P.G. [EG and G Energy Measurements, Inc., Los Alamos, NM (United States). Los Alamos Operations

1994-02-01

329

High speed x-ray gating cameras for ICF imaging applications  

SciTech Connect

High speed, high x-ray energy imaging of implosions is a key diagnostic technique in the glass laser implosion program in the USA. With the correct x-ray energy, time gated images can measure the symmetry and mix of the imploding shell into the stagnated fuel if the spatial resolution of 10 or 5 {mu}m matched by a temporal resolution of 100 or 50 psec. Several 100 psec microchannelplate (MCP) x-ray pin hole cameras have been installed and run on large laser systems with improving reliability. To increase the sensitivity of the imaging system a ring aperture microscope has been coupled to a gated MCP detector allowing imaging at up to 8 keV. To achieve 40 psec resolution, thinner MCP`s are required. On line tests with a thin low gain, but high speed MCP, followed by a d.c. MCP for higher gain have demonstrated 40 psec gating, but the second plate may lead to an unacceptable sensitivity of the camera to hard x-rays. Off line tests have extensively investigated the properties of thinner MCP`s and good agreement is seen with modeling.

Bell, P.M.; Kilkenny, J.D.; Landen, O.; Ress, D.B.; Wiedwald, J.D. [Lawrence Livermore National Lab., CA (United States); Bradley, D.K. [Rochester Univ., NY (United States). Lab. for Laser Energetics; Oertel, J.; Watt, R. [Los Alamos National Lab., NM (United States)

1992-12-01

330

High speed x-ray gating cameras for ICF imaging applications  

SciTech Connect

High speed, high x-ray energy imaging of implosions is a key diagnostic technique in the glass laser implosion program in the USA. With the correct x-ray energy, time gated images can measure the symmetry and mix of the imploding shell into the stagnated fuel if the spatial resolution of 10 or 5 [mu]m matched by a temporal resolution of 100 or 50 psec. Several 100 psec microchannelplate (MCP) x-ray pin hole cameras have been installed and run on large laser systems with improving reliability. To increase the sensitivity of the imaging system a ring aperture microscope has been coupled to a gated MCP detector allowing imaging at up to 8 keV. To achieve 40 psec resolution, thinner MCP's are required. On line tests with a thin low gain, but high speed MCP, followed by a d.c. MCP for higher gain have demonstrated 40 psec gating, but the second plate may lead to an unacceptable sensitivity of the camera to hard x-rays. Off line tests have extensively investigated the properties of thinner MCP's and good agreement is seen with modeling.

Bell, P.M.; Kilkenny, J.D.; Landen, O.; Ress, D.B.; Wiedwald, J.D. (Lawrence Livermore National Lab., CA (United States)); Bradley, D.K. (Rochester Univ., NY (United States). Lab. for Laser Energetics); Oertel, J.; Watt, R. (Los Alamos National Lab., NM (United States))

1992-12-01

331

MR-i: high-speed dual-cameras hyperspectral imaging FTS  

NASA Astrophysics Data System (ADS)

From scientific research to deployable operational solutions, Fourier-Transform Infrared (FT-IR) spectroradiometry is widely used for the development and enhancement of military and research applications. These techniques include targets IR signature characterization, development of advanced camouflage techniques, aircraft engine's plumes monitoring, meteorological sounding and atmospheric composition analysis such as detection and identification of chemical threats. Imaging FT-IR spectrometers have the capability of generating 3D images composed of multiple spectra associated with every pixel of the mapped scene. That data allow for accurate spatial characterization of target's signature by resolving spatially the spectral characteristics of the observed scenes. MR-i is the most recent addition to the MR product line series and generates spectral data cubes in the MWIR and LWIR. The instrument is designed to acquire the spectral signature of various scenes with high temporal, spatial and spectral resolution. The four port architecture of the interferometer brings modularity and upgradeability since the two output ports of the instrument can be populated with different combinations of detectors (imaging or not). For instance to measure over a broad spectral range from 1.3 to 13 ?m, one output port can be equipped with a LWIR camera while the other port is equipped with a MWIR camera. Both ports can be equipped with cameras serving the same spectral range but set at different sensitivity levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while simultaneously obtaining good measurement of the faintest parts of the scene. Various telescope options are available for the input port. Overview of the instrument capabilities will be presented as well as test results and results from field trials for a configuration with two MWIR cameras. That specific system is dedicated to the characterization of airborne targets. The expanded dynamic range allowed by the two MWIR cameras enables to simultaneously measure the spectral signature of the cold background and of the warmest elements of the scene (flares, jet engines exhausts, etc.).

Prel, Florent; Moreau, Louis; Lantagne, Stéphane; Roy, Claude; Vallières, Christian; Lévesque, Luc

2011-10-01

332

Development of epithermal neutron camera based on resonance-energy-filtered imaging with GEM  

NASA Astrophysics Data System (ADS)

An epithermal neutron camera based on energy-filtered imaging with gas electron multipliers was developed. Epithermal neutron imaging is achievable without time-of-flight detection of neutrons by using a resonance filter and a thermal neutron absorber. This technique is applicable to compact accelerator-based neutron sources. Blurring of epithermal neutron images caused by neutron scattering in the Ag resonance filter and the B4C sheet (used as a thermal neutron absorber) was investigated experimentally. The spatial resolution for epithermal neutrons with energies in the range 4.2 to 6.3 eV (corresponding to the resonance peak of 109Ag) was estimated to be 1.9±0.5 mm in a prototype detector.

Tomita, H.; Shoda, C.; Kawarabayashi, J.; Matsumoto, T.; Hori, J.; Uno, S.; Shoji, M.; Uchida, T.; Fukumoto, N.; Iguchi, T.

2012-05-01

333

Toward Real-time quantum imaging with a single pixel camera  

SciTech Connect

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.

Lawrie, Benjamin J [ORNL; Pooser, Raphael C [ORNL

2013-01-01

334

Noise reduction in brainwaves by using both EEG signals and frontal viewing camera images.  

PubMed

Electroencephalogram (EEG)-based brain-computer interfaces (BCIs) have been used in various applications, including human-computer interfaces, diagnosis of brain diseases, and measurement of cognitive status. However, EEG signals can be contaminated with noise caused by user's head movements. Therefore, we propose a new method that combines an EEG acquisition device and a frontal viewing camera to isolate and exclude the sections of EEG data containing these noises. This method is novel in the following three ways. First, we compare the accuracies of detecting head movements based on the features of EEG signals in the frequency and time domains and on the motion features of images captured by the frontal viewing camera. Second, the features of EEG signals in the frequency domain and the motion features captured by the frontal viewing camera are selected as optimal ones. The dimension reduction of the features and feature selection are performed using linear discriminant analysis. Third, the combined features are used as inputs to support vector machine (SVM), which improves the accuracy in detecting head movements. The experimental results show that the proposed method can detect head movements with an average error rate of approximately 3.22%, which is smaller than that of other methods. PMID:23669713

Bang, Jae Won; Choi, Jong-Suk; Park, Kang Ryoung

2013-05-13

335

Synchroscan streak camera imaging at a 15-MeV photoinjector with emittance exchange  

NASA Astrophysics Data System (ADS)

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.

Lumpkin, A. H.; Ruan, J.; Thurman-Keup, R.

2012-09-01

336

Noise-equivalent power characterization of an uncooled microbolometer-based THz imaging camera  

NASA Astrophysics Data System (ADS)

A THz camera based on an uncooled microbolometer 160X120 pixel array with nominal pitch of 52 ?m has been developed at INO and initial transmission and reflection images showed promise. In the present paper, the characterization of both standard infrared and THz-optimized uncooled microbolometer pixel arrays are presented at both infrared and THz wavelengths. Measurements in the THz region has been performed using non-uniform low-power quantum-cascade laser (QCL) and uniform high-power far-infrared laser (FIR laser) beams at 3 THz and 4.25 and 2.54 THz, respectively. A measurement comparison has been achieved in the infrared using a blackbody radiation. Different methods for noise-equivalent power (NEP) measurements have been investigated. These characterization methods are promising especially for non-uniform laser beams irradiated on pixel arrays. The NEP results obtained from the different methods are in good agreement independent of the method used in the experiments. The results show a high sensitivity of the THz-optimized pixel array in the THz region. Large beam area reflection imaging of obscured materials at 2.54 THz have been performed at video rates of 30 frames per second using the THz-optimized pixel array equipped with a semi-custom fast THz objective, proving that the INO THz camera provides a promising solution for stand-alone imaging systems.

Bolduc, Martin; Terroux, Marc; Tremblay, Bruno; Marchese, Linda; Savard, Eric; Doucet, Michel; Oulachgar, Hassane; Alain, Christine; Jerominek, Hubert; Bergeron, Alain

2011-05-01

337

A 1\\/2.5 inch 8.1Mpixel CMOS Image Sensor for Digital Cameras  

Microsoft Academic Search

A 1\\/2.5 inch 8.1Mpixel CMOS image sensor with 1.75mum pixel pitch is designed to operate at 2.8V for digital still camera applications and down to 2.4V in mobile applications. The chip uses top and bottom multiple channels with a double-data-rate analog signal readout at a rate of 96Mpixels\\/s, which results in total 192Mpixels\\/s. With the analog gain set to 15.875

Kwang-Bo Cho; Chiajen Lee; S. Eikedal; A. Baum; Jutao Jiang; Chen Xu; Xiaofeng Fan; R. Kauffman

2007-01-01

338

Probing subtle fluorescence dynamics in cellular proteins by streak camera based fluorescence lifetime imaging microscopy  

NASA Astrophysics Data System (ADS)

We report the cell biological applications of a recently developed multiphoton fluorescence lifetime imaging microscopy system using a streak camera (StreakFLIM). The system was calibrated with standard fluorophore specimens and was shown to have high accuracy and reproducibility. We demonstrate the applicability of this instrument in living cells for measuring the effects of protein targeting and point mutations in the protein sequence, which are not obtainable by conventional intensity-based fluorescence microscopy methods. We discuss the relevance of such time-resolved information in quantitative energy transfer microscopy and in measurement of the parameters that characterize the intracellular physiology.

Krishnan, R. V.; Biener, Eva; Zhang, Jian-Hua; Heckel, Robert; Herman, Brian

2003-12-01

339

PCA-based spatially adaptive denoising of CFA images for single-sensor digital cameras.  

PubMed

Single-sensor digital color cameras use a process called color demosiacking to produce full color images from the data captured by a color filter array (CAF). The quality of demosiacked images is degraded due to the sensor noise introduced during the image acquisition process. The conventional solution to combating CFA sensor noise is demosiacking first, followed by a separate denoising processing. This strategy will generate many noise-caused color artifacts in the demosiacking process, which are hard to remove in the denoising process. Few denoising schemes that work directly on the CFA images have been presented because of the difficulties arisen from the red, green and blue interlaced mosaic pattern, yet a well-designed "denoising first and demosiacking later" scheme can have advantages such as less noise-caused color artifacts and cost-effective implementation. This paper presents a principle component analysis (PCA)-based spatially-adaptive denoising algorithm, which works directly on the CFA data using a supporting window to analyze the local image statistics. By exploiting the spatial and spectral correlations existing in the CFA image, the proposed method can effectively suppress noise while preserving color edges and details. Experiments using both simulated and real CFA images indicate that the proposed scheme outperforms many existing approaches, including those sophisticated demosiacking and denoising schemes, in terms of both objective measurement and visual evaluation. PMID:19273050

Zheng, Lei; Lukac, Rastislav; Wu, Xiaolin; Zhang, David

2009-04-01

340

Color video camera capable of 1,000,000 fps with triple ultrahigh-speed image sensors  

NASA Astrophysics Data System (ADS)

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.

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

341

Research of sub-pixel sub-division location algorithm for spot center of digital aerial survey camera image  

NASA Astrophysics Data System (ADS)

So far, the geometric laboratory calibration system of optical aerial survey camera has been well established, while there is not a perfect system for digital aerial survey camera and the calibration of digital camera has not been included in the metrological verification system. In order to make the photogrammetry project rule-based, it's imperative to establish geometric laboratory calibration system of digital survey camera. Exact measuring angle method is the most common method to calibrate the camera in lab. The sub-pixel sub-division location of spot center for point-source image of digital camera is one of the key techniques to calibrate the camera based on the exact measuring angle method in lab. A novel location algorithm is proposed on account of the realities of the lab system. First, the Gauss filter is introduced to reduce the noise from the stray light and so on. Then the integration of iterative threshold segmentation and seed region growing is adopted to identify the general location of the spot. Thirdly, using the bilinear interpolation, the pixels used to estimate the location are increased. Finally, we use the proposed improved moment method to determinate the precise centroid location of the digital image. Experimental results show that the spots are identified with 93 percent accuracy and the centroid accuracy is superior to 1/40 of a pixel and improves about 2 to 4 times than other algorithms, which indicates that the proposed method is effective, convenient and precision.

Yu, Xiu-juan; Pang, Xu-feng; Fang, Ai-ping; Qi, Wei-jun

2013-08-01

342

Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera  

PubMed Central

3D imaging with Time-of-Flight (ToF) cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR)-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

Chiabrando, Filiberto; Chiabrando, Roberto; Piatti, Dario; Rinaudo, Fulvio

2009-01-01

343

A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M  

SciTech Connect

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.

von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Jones, S.; Paoletti, F. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Petravich, G. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics); Rimini,

1993-05-01

344

Real-time image processing and fusion for a new high-speed dual-band infrared camera  

NASA Astrophysics Data System (ADS)

A dual-band infrared camera system based on a dual-band quantum well infrared photodetector (QWIP) has been developed for acquiring images from both the mid-wavelength (MWIR) and long-wavelength (LWIR) infrared spectral band. The system delivers exactly pixel-registered simultaneously acquired images. It has the advantage that appropriate signal and image processing permit to exploit differences in the characteristics of those bands. Thus, the camera reveals more information than a single-band camera. It helps distinguishing between targets and decoys and has the ability to defeat many IR countermeasures such as smoke, camouflage and flares. Furthermore, the system permits to identify materials (e.g. glass, asphalt, slate, etc.), to distinguish sun reflections from hot objects and to visualize hot exhaust gases. Furthermore, dedicated software for processing and exploitation in real-time extends the application domain of the camera system. One component corrects the images and allows for overlays with complementary colors such that differences become apparent. Another software component aims at a robust estimation of transformation parameters of consecutive images in the image stream for image registration purposes. This feature stabilizes the images also under rugged conditions and it allows for the automatic stitching of the image stream to construct large mosaic images. Mosaic images facilitate the inspection of large objects and scenarios and create a better overview for human observers. In addition, image based MTI (moving target indication) also for the case of a moving camera is under development. This component aims at surveillance applications and could also be used for camouflage assessment of moving targets.

Müller, Markus; Schreer, Oliver; López Sáenz, Monica

2007-05-01

345

SIMULTANEOUS DUAL-RADIONUCLIDE MYOCARDIAL PERFUSION IMAGING WITH A SOLID-STATE DEDICATED CARDIAC CAMERA  

PubMed Central

We compared simultaneous dual-radionuclide stress and rest myocardial perfusion imaging (MPI) with a novel solid-state cardiac camera and a conventional SPECT camera with separate stress and rest acquisitions. Methods 24 consecutive patients (64.5 ± 11.8 years, 16 men) were injected with 74 MBq of 201Tl (rest) and 250 MBq 99mTc-MIBI (stress). Conventional MPI acquisition times for stress and rest were 21 min and 16 min, respectively. A simultaneous dual-radionuclide (DR) 15 minute list mode gated acquisition was performed on D-SPECT (Spectrum-dynamics, Caesarea, Israel). The DR D-SPECT data were processed using a spillover and scatter correction method. We compared DR D-SPECT images with conventional SPECT images by visual analysis employing the 17-segment model and a 5-point scale (0=normal, 4=absent) to calculate the summed stress and rest scores (SSS and SRS, respectively) and the % visual perfusion defect (TPD) at stress and rest, by dividing the stress and rest scores, respectively, by 68 and multiplying by 100. TPD <5% was considered normal. Image quality was assessed on a 4-point scale (1=poor, 4=very good) and gut activity was assessed on a 4-point scale (0=none, 3=high). Results Conventional MPI was abnormal at stress in 17 patients and at rest in 9 patients. In the 17 abnormal stress studies DR D-SPECT MPI was abnormal in 113 vs. 93 abnormal segments by conventional MPI. In the nine abnormal rest studies DR D-SPECT was abnormal in 45 vs. 48 segments abnormal by conventional MPI. SSS, SRS, TPD stress and TPD rest on conventional SPECT and DR D-SPECT highly correlated (r=0.9790, 0.9694, 0.9784, 0.9710, respectively; p<0.0001 for all). In addition, 6 patients had significantly larger perfusion defects on DR D-SPECT stress images, including five of 11 patients who were imaged earlier on D-SPECT than conventional SPECT. Conclusion D-SPECT enables fast and high quality simultaneous DR MPI in a single imaging session with comparable diagnostic performance and image quality to conventional SPECT. Modifications of the injected doses and of the imaging protocol with DR D-SPECT may enable shortening of imaging time, reducing radiation exposure and shortening significantly patient stay in the department.

Ben-Haim, S.; Kacperski, K.; Hain, S.; Van Gramberg, D.; Hutton, B.F.; Waddington, W.A.; Sharir, T.; Roth, N.; Berman, D.S.; Ell, P.J.

2011-01-01

346

Color shift model-based image enhancement for digital multifocusing based on a multiple color-filter aperture camera  

Microsoft Academic Search

In this paper, we present a novel image enhancement approach using a color shift model-based multiple color-filter aperture (MCA) camera for digital multifocusing. The proposed image enhancement algorithm consists of three steps; (i) cluster-based region-of-interest (ROI) estimation, (ii) image registration using phase correlation matching (PCM) and fusion, and (iii) image enhancement using spatially adaptive noise smoothing based on the alpha

Eunsung Lee; Wonseok Kang; Sangjin Kim; Joonki Paik

2010-01-01

347

Implementation of a continuous scanning procedure and a line scan camera for ?thin-sheet laser imaging microscopy  

PubMed Central

We report development of a continuous scanning procedure and the use of a time delay integration (TDI) line scan camera for a light-sheet based microscope called a thin-sheet laser imaging microscope (TSLIM). TSLIM is an optimized version of a light-sheet fluorescent microscope that previously used a start/stop scanning procedure to move the specimen through the thinnest portion of a light-sheet and stitched the image columns together to produce a well-focused composite image. In this paper, hardware and software enhancements to TSLIM are described that allow for dual sided, dual illumination lasers, and continuous scanning of the specimen using either a full-frame CCD camera and a TDI line scan camera. These enhancements provided a ~70% reduction in the time required for composite image generation and a ~63% reduction in photobleaching of the specimen compared to the start/stop procedure.

Schacht, Peter; Johnson, Shane B.; Santi, Peter A.

2010-01-01

348

Resolving depth-measurement ambiguity with commercially available range imaging cameras  

NASA Astrophysics Data System (ADS)

Time-of-flight range imaging is typically performed with the amplitude modulated continuous wave method. This involves illuminating a scene with amplitude modulated light. Reflected light from the scene is received by the sensor with the range to the scene encoded as a phase delay of the modulation envelope. Due to the cyclic nature of phase, an ambiguity in the measured range occurs every half wavelength in distance, thereby limiting the maximum useable range of the camera. This paper proposes a procedure to resolve depth ambiguity using software post processing. First, the range data is processed to segment the scene into separate objects. The average intensity of each object can then be used to determine which pixels are beyond the non-ambiguous range. The results demonstrate that depth ambiguity can be resolved for various scenes using only the available depth and intensity information. This proposed method reduces the sensitivity to objects with very high and very low reflectance, normally a key problem with basic threshold approaches. This approach is very flexible as it can be used with any range imaging camera. Furthermore, capture time is not extended, keeping the artifacts caused by moving objects at a minimum. This makes it suitable for applications such as robot vision where the camera may be moving during captures. The key limitation of the method is its inability to distinguish between two overlapping objects that are separated by a distance of exactly one non-ambiguous range. Overall the reliability of this method is higher than the basic threshold approach, but not as high as the multiple frequency method of resolving ambiguity.

McClure, Shane H.; Cree, Michael J.; Dorrington, Adrian A.; Payne, Andrew D.

2010-02-01

349

Efficient smart CMOS camera based on FPGAs oriented to embedded image processing.  

PubMed

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

Bravo, Ignacio; Baliñas, Javier; Gardel, Alfredo; Lázaro, José L; Espinosa, Felipe; García, Jorge

2011-02-24

350

Electronic still camera  

Microsoft Academic Search

A handheld, programmable, digital camera is disclosed that supports a variety of sensors and has program control over the system components to provide versatility. The camera uses a high performance design which produces near film quality images from an electronic system. The optical system of the camera incorporates a conventional camera body that was slightly modified, thus permitting the use

S. Douglas Holland

1992-01-01

351

Influence of deep seated causes on geologic deformation recognized on satellite images made with a hand held camera  

Microsoft Academic Search

With the aid of different methods of interpretation of satellite images we have tried to derive some specific information about the structure and behaviour of the uppermost parts of the lithosphere. The reconaissance of deep seated features is like a remote sensing there is a high degree of information contained in hand camera images made during the experiment BIOSPHERE for

P. Bankwitz; K.-H. Marek

1981-01-01

352

Collaborative acquisition of multi-view face images in real-time using a wireless camera network  

Microsoft Academic Search

In order to support real-time face recognition using a wireless camera network, we design a data acquisition service to quickly and reliably acquire face images of human subjects from multiple views and to simultaneously index each acquired image into its corresponding pose. In comparison with detection of frontal faces, the detection of non-frontal faces with unknown pose is a much

S. Parupati; R. Bakkannagari; S. Sankar; V. Kulathumani

2011-01-01

353

A 250000-pixel image sensor with FET amplification at each pixel for high-speed television cameras  

Microsoft Academic Search

An amplified MOS imager (AMI) for use in each pixel in a high-speed TV camera is discussed. The AMI performs such functions as amplification, readout, and resetting independently and completely. Thus the AMI is easier to operate and completely free from image lag, and has relatively little smear (2*10 -5) compared with other devices. The AMI can also handle both

Fumihiko Andoh; K. Taketoshi; J. Yamazaki; M. Sugawara; Y. Fujita; K. Mitani; Y. Matuzawa; K. Miyata; S. Araki

1990-01-01

354

Obstacle detection in highway environment by colour CCD camera and image processing prototype installed in a vehicle  

Microsoft Academic Search

This paper deals with a demonstrator which has been developed at THOMSON-CSF\\/LER in cooperation with French car manufacturers (RENAULT and PSA Research Divisions) during the PROMETHEUS Programme. The vehicle is equipped with a video camera and image processing and visualization hardware. This system has been realized to demonstrate the important role that can be played by electronics, image and information

Stkphane Raboisson; Philippe Schmouker

1994-01-01

355

A 3D HIDAC-PET camera with sub-millimeter resolution for imaging small animals  

SciTech Connect

A HIDAC-PET camera consisting essentially of 5 million 0.5 mm gas avalanching detectors has been constructed for small-animal imaging. The particular HIDAC advantage--a high 3D spatial resolution--has been improved to 0.95 mm fwhm and to 0.7 mm fwhm when reconstructing with 3D-OSEM methods incorporating resolution recovery. A depth-of-interaction resolution of 2.5 mm is implicit, due to the laminar construction. Scatter-corrected sensitivity, at 8.9 cps/kBq (i.e. 0.9%) from a central point source, or 7.2 cps/kBq (543 cps/kBq/cm{sup 3}) from a distributed (40 mm diameter, 60 mm long) source is now much higher than previous, and other, work. A field-of-view of 100 mm (adjustable to 200 mm) diameter by 210 mm axially permits whole-body imaging of small animals, containing typically 4MBqs of activity, at 40 kcps of which 16% are random coincidences, with a typical scatter fraction of 44%. Throughout the field-of-view there are no positional distortions and relative quantitation is uniform to {+-} 3.5%, but some variation of spatial resolution is found. The performance demonstrates that HIDAC technology is quite appropriate for small-animal PET cameras.

Jeavons, A.P.; Chandler, R.A.; Dettmar, C.A.R. [Oxford Positron Systems (United Kingdom)

1999-06-01

356

Real time plume and laser spot recognition in IR camera images  

SciTech Connect

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.

Moore, K.R.; Caffrey, M.P.; Nemzek, R.J.; Salazar, A.A.; Jeffs, J. [Los Alamos National Lab., NM (United States); Andes, D.K.; Witham, J.C. [Naval Air Weapons Station, China Lake, CA (United States)

1997-08-01

357

Single-camera panoramic stereo imaging system with a fisheye lens and a convex mirror.  

PubMed

This paper presents a panoramic stereo imaging system which uses a single camera coaxially combined with a fisheye lens and a convex mirror. It provides the design methodology, trade analysis, and experimental results using commercially available components. The trade study shows the design equations and the various tradeoffs that must be made during design. The system's novelty is that it provides stereo vision over a full 360-degree horizontal field-of-view (FOV). Meanwhile, the entire vertical FOV is enlarged compared to the existing systems. The system is calibrated with a computational model that can accommodate the non-single viewpoint imaging cases to conduct 3D reconstruction in Euclidean space. PMID:21451610

Li, Weiming; Li, Y F

2011-03-28

358

Estimation of Enterococci Input from Bathers and Animals on A Recreational Beach Using Camera Images  

PubMed Central

Enterococci, are used nationwide as a water quality indicator of marine recreational beaches. Prior research has demonstrated that enterococci inputs to the study beach site (located in Miami, FL) are dominated by non-point sources (including humans and animals). We have estimated their respective source functions by developing a counting methodology for individuals to better understand their non-point source load impacts. The method utilizes camera images of the beach taken at regular time intervals to determine the number of people and animal visitors. The developed method translates raw image counts for weekdays and weekend days into daily and monthly visitation rates. Enterococci source functions were computed from the observed number of unique individuals for average days of each month of the year, and from average load contributions for humans and for animals. Results indicate that dogs represent the larger source of enterococci relative to humans and birds.

D, Wang John; M, Solo-Gabriele Helena; M, Abdelzaher Amir; E, Fleming Lora

2010-01-01

359

A two camera video imaging system with application to parafoil angle of attack measurements  

NASA Astrophysics Data System (ADS)

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.

Meyn, Larry A.; Bennett, Mark S.

1991-01-01

360

High-resolution Vesta Low Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images  

NASA Astrophysics Data System (ADS)

The Dawn Framing Camera (FC) acquired close to 10,000 clear filter images of Vesta with a resolution of about 20 m/pixel during the Low Altitude Mapping Orbit (LAMO) between December 2011 and April 2012. We ortho-rectified these images and produced a global high-resolution uncontrolled mosaic of Vesta. This global mosaic is the baseline for a high-resolution Vesta atlas that consists of 30 tiles mapped at a scale between 1:200,000 and 1:225,180. 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 [http://dawn_gis.dlr.de/atlas].

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

2013-09-01

361

Application of a digital high speed camera and image processing system for investigations of short-term hypersonic fluids  

NASA Astrophysics Data System (ADS)

The design and application of a digital high sped image data capturing system with a following image processing system applied to the Bremer Hochschul Hyperschallkanal BHHK is the content of this presentation. It is also the result of the cooperation between the departments aerodynamic and image processing at the ZARM-institute at the Drop Tower of Brennen. Similar systems are used by the combustion working group at ZARM and other external project partners. The BHHK, camera- and image storage system as well as the personal computer based image processing software are described next. Some examples of images taken at the BHHK are shown to illustrate the application. The new and very user-friendly Windows 32-bit system is capable to capture all camera data with a maximum pixel clock of 43 MHz and to process complete sequences of images in one step by using only one comfortable program.

Renken, Hartmut; Oelze, Holger W.; Rath, Hans J.

1998-04-01

362

CMOS detector arrays in a virtual 10-kilopixel camera for coherent terahertz real-time imaging.  

PubMed

We demonstrate the principle applicability of antenna-coupled complementary metal oxide semiconductor (CMOS) field-effect transistor arrays as cameras for real-time coherent imaging at 591.4 GHz. By scanning a few detectors across the image plane, we synthesize a focal-plane array of 100×100 pixels with an active area of 20×20 mm2, which is applied to imaging in transmission and reflection geometries. Individual detector pixels exhibit a voltage conversion loss of 24 dB and a noise figure of 41 dB for 16 ?W of the local oscillator (LO) drive. For object illumination, we use a radio-frequency (RF) source with 432 ?W at 590 GHz. Coherent detection is realized by quasioptical superposition of the image and the LO beam with 247 ?W. At an effective frame rate of 17 Hz, we achieve a maximum dynamic range of 30 dB in the center of the image and more than 20 dB within a disk of 18 mm diameter. The system has been used for surface reconstruction resolving a height difference in the ?m range. PMID:22344098

Boppel, Sebastian; Lisauskas, Alvydas; Max, Alexander; Krozer, Viktor; Roskos, Hartmut G

2012-02-15

363

An ETC and Image Simulation Suite for any ground based Camera & Telescope  

NASA Astrophysics Data System (ADS)

We present methods which comprise a highly realistic exposure time calculator (ETC) for planning observations, and a simulator for the creation of realistic astronomical images - both of which are designed for any combination of location, telescope, filter and detector. The unique principle is that we begin with the physical properties of the stellar sources, as output by N-body simulations and evolutionary codes. Their fluxes (energy spectra) are computed, scaled for distance, and fed through a series of propagation stages applying the effects of the interstellar medium, the Earth's atmosphere, and the passband throughputs of the telescope optics, filters and the camera/detector, including all expected noise sources. We maintain flux propagation as a function of wavelength - not as an approximate integration over typical passbands. The simulator uses the fluxes output by the ETC to construct the actual images. Either single images or a time-series data set can be simulated; the PSF seeing model and airmass change realistically, and the magnitude of selected star(s) can be changed by some defined amount from image to image, to model variability. The main packages used are IRAF, DAOPHOT, and Perl.

Sheehan, B.; Lane, C.; Butler, R.

2006-07-01

364

Calibration and development for increased accuracy of 3D range imaging cameras  

NASA Astrophysics Data System (ADS)

Range imaging has become a valuable technology for many kinds of applications in recent years. Numerous systematic deviations occur during the measurement process carried out by available systems. These systematics are partly excited by external and partly excited by internal influences. In this paper the following investigations will be presented in closer detail. First the statistics of the distance measurement of the analyzed range imaging cameras SwissRangerTM SR-2 and SR-3000 will be shown. Besides the question if the measurements are Gaussian distributed, the precision of the measurements will be shown. This aspect is of importance to answer the question if the mean value of a series of measurements leads to more precise data. Second diverse influencing parameters like the target's reflectivity and external as well as internal temperature are aimed. The dependency of the distance measurements with respect to the amplitude is one of the main aspects in this paper. A specialized set up has been developed in order to derive experimentally the detailed correlation, which is expressed in terms of linearity deviations. Besides the results of some specific aspects, an overview of the recommended calibration procedure is given. The reader of this paper will be enabled to understand the calibration steps needed to gain highly accurate data from the investigated range imaging cameras. Due to the fact that range imaging cameras are on their way to become state of the art in 3D capturing of the environment, it is of importance to develop strategies for the calibration of such sensors in order to enable users to revert to these principles for the sake of simplicity. Therefore, these strategies long for sophisticated approaches and reliable results of investigations. This paper will introduce such an approach to be discussed within the scientific and user environment. One of the main achievements of this work is the introduction of a method to significantly decrease the influence of temperature on the distance measurements by means of a differential measurement principle setup. The verification of the functionality is presented, as well.

Kahlmann, Timo; Ingensand, Hilmar

2008-04-01

365

High speed x-ray imaging camera using a structured CsI(Tl) scintillator  

SciTech Connect

New third generation x-ray sources such as the Advanced Photon Source have created a need for a detector that can provide multiple frames of detailed x-ray images on the millisecond time scale. Such detectors will prove invaluable in applications such as time-resolved x-ray diffraction, x-ray microtomography, as well as materials science applications like polymer processing. Currently, detectors capable of acquiring high resolution x-ray images at such high speed do not exist, thus limiting progress in many of these important areas of research. To address these needs the authors have developed a prototype fast x-ray imaging system, using a structured CsI(Tl) scintillator coupled to a fast-frame 1K x 1K CCD. The system has been successfully employed to capture 1024 x 64 pixel x-rays images at a rate of 1000 frames per second (fps) with a 12 bit dynamic range. The system exceeds the capabilities of the current high speed x-ray imaging systems which typically operate at the rate of 30 fps. Fabrication of a large area detector is currently underway, using a microstructured CsI(Tl) scintillator coupled to a fast-frame CCD with a 3:1 fiberoptic taper. The camera will operate in a burst mode, acquiring 8 1K x 1K images at rates up to 1000 frames per second with 12 bit dynamic range. Higher image capture speeds can be accomplished by reducing the image area. This paper will discuss the specific characteristics of the CsI(Tl) screens, experimental details of the prototype and the new design for the large area detector being developed specifically for time-resolved x-ray diffraction experiments in structural biology.

Nagarkar, V.V.; Tipnis, S.V.; Gupta, T.K.; Miller, S.R.; Gaysinskiy, V.B.; Klugerman, Y.; Squillante, M.R.; Entine, G. [Radiation Monitoring Devices, Inc., Watertown, MA (United States); Moses, W.W. [Lawrence Berkeley National Lab., CA (United States)

1999-06-01

366

Field-programmable gate array-based hardware architecture for high-speed camera with KAI-0340 CCD image sensor  

NASA Astrophysics Data System (ADS)

We present a field-programmable gate array (FPGA)-based hardware architecture for high-speed camera which have fast auto-exposure control and colour filter array (CFA) demosaicing. The proposed hardware architecture includes the design of charge coupled devices (CCD) drive circuits, image processing circuits, and power supply circuits. CCD drive circuits transfer the TTL (Transistor-Transistor-Logic) level timing Sequences which is produced by image processing circuits to the timing Sequences under which CCD image sensor can output analog image signals. Image processing circuits convert the analog signals to digital signals which is processing subsequently, and the TTL timing, auto-exposure control, CFA demosaicing, and gamma correction is accomplished in this module. Power supply circuits provide the power for the whole system, which is very important for image quality. Power noises effect image quality directly, and we reduce power noises by hardware way, which is very effective. In this system, the CCD is KAI-0340 which is can output 210 full resolution frame-per-second, and our camera can work outstandingly in this mode. The speed of traditional auto-exposure control algorithms to reach a proper exposure level is so slow that it is necessary to develop a fast auto-exposure control method. We present a new auto-exposure algorithm which is fit high-speed camera. Color demosaicing is critical for digital cameras, because it converts a Bayer sensor mosaic output to a full color image, which determines the output image quality of the camera. Complexity algorithm can acquire high quality but cannot implement in hardware. An low-complexity demosaicing method is presented which can implement in hardware and satisfy the demand of quality. The experiment results are given in this paper in last.

Wang, Hao; Yan, Su; Zhou, Zuofeng; Cao, Jianzhong; Yan, Aqi; Tang, Linao; Lei, Yangjie

2013-08-01

367

A pipelined architecture for real-time correction of barrel distortion in wide-angle camera images  

Microsoft Academic Search

An efficient pipelined architecture for the real-time correction of barrel distortion in wide-angle camera images is presented in this paper. The distortion correction model is based on least-squares estimation to correct the nonlinear distortion in images. The model parameters include the expanded\\/corrected image size, the back-mapping coefficients, distortion center, and corrected center. The coordinate rotation digital computer (CORDIC) based hardware

Hau T. Ngo; Vijayan K. Asari

2005-01-01

368

MCNP-4c simulations to investigate shielding of scintillation cameras for conjugate imaging of I-123 labeled brain agents  

Microsoft Academic Search

Monte Carlo simulations were performed to characterize various shielding configurations for an iodine-123 (I-123) imaging system. The system comprises two small (10×10 cm) field-of-view (FOV) gamma cameras to be used for conjugate imaging of I-123 labeled brain agents. 83% of I-123 decays result in 159 keV gamma emissions, which can be readily imaged; while 3% result in emissions with energies

D. N. Jangha; Robert A. Mintzer; John D. Valentine; John N. Aarsvold

2001-01-01

369

Space-bandwidth extension in parallel phase-shifting digital holography using a four-channel polarization-imaging camera.  

PubMed

We propose a method for extending the space bandwidth (SBW) available for recording an object wave in parallel phase-shifting digital holography using a four-channel polarization-imaging camera. A linear spatial carrier of the reference wave is introduced to an optical setup of parallel four-step phase-shifting interferometry using a commercially available polarization-imaging camera that has four polarization-detection channels. Then a hologram required for parallel two-step phase shifting, which is a technique capable of recording the widest SBW in parallel phase shifting, can be obtained. The effectiveness of the proposed method was numerically and experimentally verified. PMID:23939081

Tahara, Tatsuki; Ito, Yasunori; Xia, Peng; Awatsuji, Yasuhiro; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

2013-07-15

370

Order statistic-neural network hybrid filters for gamma camera-Bremsstrahlung image restoration  

SciTech Connect

A new class of filters, an order statistic and neural network hybrid filter (OSNNH), is proposed for the restoration of gamma camera images, based on the measured modulation transfer function. This filter shares the advantages of both neural network for deconvolution and advanced nonlinear filtering for noise removal and edge enhancement. Planar images of [beta]-emitting radionuclides are used to evaluate the new filter because they exhibit higher degradation than images of single photon emitters due to increased photon scattering and collimator septal penetration. The filter performance is quantitatively evaluated and compared to that of the Wiener filter by investigating the relationship between the externally measured counts from sources of phosphorus-32 ([sup 32]P) at various depths in water. An effective linear attenuation coefficient for [sup 32]P is determined equal to 0.13 cm[sup [minus]1] and 0.14 cm[sup [minus]1] for the OSNNH and the Wiener filters, respectively. Evaluation of phantom and patient filtered images demonstrates that the OSNNH filter avoids ring effects caused by the ill-conditioned blur matrix and noise overriding caused by matrix inversion, typical of other restoration filters such as the wiener. Although further work is required on the optimization of the OSNNH filter, the present results suggest that this new restoration method may be suitable for quantitative system calibration using [beta]-emitters, important for antibody therapy management, and for broader applications to single-photon studies.

Wei Qian; Kallergi, M.; Clarke, L.P. (Univ. of South Florida, Tampa, FL (United States). Dept. of Radiology)

1993-03-01

371

Thermal imaging of micro-structured polymers with high-speed infrared camera  

NASA Astrophysics Data System (ADS)

Creating and monitoring micro-scale thermal transfer in micro-structured thin polymer films is presented in this study. Thermal imaging is captured using IR camera equipped with optics designed for the mid- and long- IR wavelengths. The non-contact thermal imaging method is preferred to visualize the distribution of temperature and characterizes the thermal properties of complex multi-component/layered structures of thermal functioning materials. The work is to present a method for thermal wave imaging that is applied to measure the thermal diffusivity of the micro-structured polymer thin films using a modulated laser-diode spot heating irradiated to the rear surface of the film, observed at different modulation frequencies. The procedure is based on the micro-scale thermography and the analysis is based on the computational phase lock-in system for the temporal evolution extracted from the sequence of infrared image. The in-plane surface profiles of the amplitude and phase are precisely calculated and the principle for eliminating the effects of heat loss is examined.

Morikawa, J.; Hashimoto, T.

2011-12-01

372

ANTS — a simulation package for secondary scintillation Anger-camera type detector in thermal neutron imaging  

NASA Astrophysics Data System (ADS)

A custom and fully interactive simulation package ANTS (Anger-camera type Neutron detector: Toolkit for Simulations) has been developed to optimize the design and operation conditions of secondary scintillation Anger-camera type gaseous detectors for thermal neutron imaging. The simulation code accounts for all physical processes related to the neutron capture, energy deposition pattern, drift of electrons of the primary ionization and secondary scintillation. The photons are traced considering the wavelength-resolved refraction and transmission of the output window. Photo-detection accounts for the wavelength-resolved quantum efficiency, angular response, area sensitivity, gain and single-photoelectron spectra of the photomultipliers (PMTs). The package allows for several geometrical shapes of the PMT photocathode (round, hexagonal and square) and offers a flexible PMT array configuration: up to 100 PMTs in a custom arrangement with the square or hexagonal packing. Several read-out patterns of the PMT array are implemented. Reconstruction of the neutron capture position (projection on the plane of the light emission) is performed using the center of gravity, maximum likelihood or weighted least squares algorithm. Simulation results reproduce well the preliminary results obtained with a small-scale detector prototype. ANTS executables can be downloaded from http://coimbra.lip.pt/~andrei/.

Morozov, A.; Defendi, I.; Engels, R.; Fraga, F. A. F.; Fraga, M. M. F. R.; Guerard, B.; Jurkovic, M.; Kemmerling, G.; Manzin, G.; Margato, L. M. S.; Niko, H.; Pereira, L.; Petrillo, C.; Peyaud, A.; Piscitelli, F.; Raspino, D.; Rhodes, N. J.; Sacchetti, F.; Schooneveld, E. M.; Van Esch, P.; Zeitelhack, K.

2012-08-01

373

Limb imaging of the Venus O2 visible nightglow with the Venus Monitoring Camera  

NASA Astrophysics Data System (ADS)

investigated the Venus O2 visible nightglow with imagery from the Venus Monitoring Camera on Venus Express. Drawing from data collected between April 2007 and January 2011, we study the global distribution of this emission, discovered in the late 1970s by the Venera 9 and 10 missions. The inferred limb-viewing intensities are on the order of 150 kR at the lower latitudes and seem to drop somewhat toward the poles. The emission is generally stable, although there are episodes when the intensities rise up to 500 kR. We compare a set of Venus Monitoring Camera observations with coincident measurements of the O2 nightglow at 1.27 µm made with the Visible and Infrared Thermal Imaging Spectrometer, also on Venus Express. From the evidence gathered in this and past works, we suggest a direct correlation between the instantaneous emissions from the two O2 nightglow systems. Possible implications regarding the uncertain origin of the atomic oxygen green line at 557.7 nm are noted.

GarcíA MuñOz, A.; Hueso, R.; SáNchez-Lavega, A.; Markiewicz, W. J.; Titov, D. V.; Witasse, O.; Opitz, A.

2013-06-01

374

TRIDENT: an Infrared Differential Imaging Camera Optimized for the Detection of Methanated Substellar Companions  

SciTech Connect

A near-infrared camera in use at the Canada-France-Hawaii Telescope (CFHT) and at the 1.6-m telescope of the Observatoire du Mont-Megantic is described. The camera is based on a Hawaii-1 1024 x 1024 HgCdTe array detector. Its main feature is to acquire three simultaneous images at three wavelengths across the methane absorption bandhead at 1.6 {micro}m, enabling, in theory, an accurate subtraction of the stellar point spread function (PSF) and the detection of faint close methanated companions. The instrument has no coronoagraph and features fast data acquisition, yielding high observing efficiency on bright stars. The performance of the instrument is described, and it is illustrated by laboratory tests and CFHT observations of the nearby stars GL526, {nu}-And and {chi}-And. TRIDENT can detect (6{sigma}) a methanated companion with {Delta}H = 9.5 at 0.5'' separation from the star in one hour of observing time. Non-common path aberrations and amplitude modulation differences between the three optical paths are likely to be the limiting factors preventing further PSF attenuation. Instrument rotation and reference star subtraction improve the detection limit by a factor of 2 and 4 respectively. A PSF noise attenuation model is presented to estimate the non-common path wavefront difference effect on PSF subtraction performance.

Marois, C; Doyon, R; Nadeau, D; Racine, R; Riopel, M; Vallee, P; Lafreniere, D

2005-04-08

375

Imaging the Jovian Magnetosphere in Energetic Neutral Atoms with the Cassini/Huygens Magnetospheric Imaging Instrument Ion and Neutral Camera  

NASA Astrophysics Data System (ADS)

During the flyby of Jupiter on its cruise to Saturn, the Cassini/Huygens spacecraft collected unique data with a broad assortment of instruments. The Magnetospheric Imaging Instrument (MIMI) measured in-situ energetic ions and electrons, performed charge and mass analysis of both interstellar pickup ions and Jovian source ions, and remotely imaged the Jovian magnetosphere in energetic neutral atom (ENA) emissions. The ENA images were measured with the Ion and Neutral Camera (INCA) [Mitchell et al., 1998]. INCA images ENA in the velocity range from about 1200 km/s to 8000 km/s, which for hydrogen corresponds to about 8 keV to about 350 keV. Jupiter, as expected based on Voyager measurements [Kirsch et al., 1981; Cheng 1986], is a weak ENA source. The expected INCA response was modeled by Mauk et al., 1998. The INCA sensor was run in a mode for which images were obtained only below about 80 keV/nucleon. The images obtained are quite close to the predictions of Mauk et al., both in conformation and in intensity. They are consistent with the source strength of the Jovian magnetosphere remaining essentially constant between 1979 and 2001. Rough inferences as to the composition of the ENA show that there is a mix of hydrogen as well as heavier atoms, most probably oxygen and sulfur. These first-ever images of Jupiter's magnetosphere provide a taste of what we can look forward to at Saturn, although the distance of this flyby (140 Rj) allows only hints of the magnetospheric structure to be resolved with this instrument, which is designed for a closer vantage point. Mitchell, D. G., A. F. Cheng, K. C. Hsieh, S. M. Krimigis, E. P. Keath, S. E. Jaskulek, B. H. Mauk, R. W. McEntire, E. C. Roelof, C. E. Schlemm, B. E. Tossman, and D. J. Williams, The ion neutral camera for the Cassini Mission to Saturn and Titan, Measurement Techniques in Space Plasmas, Fields, R. F. Pfaff, J. E. Borovsky, and D. T. Young, ed., Geophysical Monograph 103, p281, AGU, 1998. Kirsch, E., S. M. Krimigis, J. Johl, and E. Keath, Upper limits for X-ray and energetic neutral particle emission from Jupiter: Voyager 1 results, Geophys. Res. Lett., 8, 169, 1981. Mauk, B.H., S.M. Krimigis, D.G. Mitchell, and E.C. Roelof, Energetic neutral atom imaging of Jupiter's magnetosphere using the Cassini MIMI instrument, Adv. Space Res., 21, 1483, 1998.

Mitchell, D. G.; Krimigis, S. M.; Mauk, B. H.

2001-05-01

376

Optical system module having zooming function and image quality of mega pixel for a cellular phone camera  

NASA Astrophysics Data System (ADS)

We designed and developed a cellular phone camera like HD digital still camera having zooming function. To design an optical system module having the auto-zooming and the image quality of 2M mega pixel using Code V, we considered 6 lenses which were four aspheric plastic lenses and two glass lenses. The specifications of designed optical system module for a cellular phone camera were the focal length of 4.29mm at wide position to 10.55mm at tele position, fnumber of 3.2 at wide position to 5.3 at tele position, and field of view of 27.4 degree at tele position to 65.8 degree at wide position. Its zoom ratio was 2.5. The values of modulation transfer function (MTF) at 200lp/mm of the designed optical system module were over 21% at zoom position. We applied the design results of optical system module to the fabrication of a cellular phone camera having the zoom ratio of 2.5 and the image quality of 2M mega pixel, and adopted the aspheric glass lens having higher abbe number to compensate chromatic aberration and the VCM (Voice Coil Motor) as sub-miniature motor. We fabricated the optical module system having zoom ratio of 2.5 and image quality of 2M mega pixel in order to apply to a HD cellular phone camera.

Park, Seong Jong; Lee, Jong Jin; Chung, Chang Sub

2009-08-01

377

Tower Camera Handbook  

SciTech Connect

The tower camera in Barrow provides hourly images of ground surrounding the tower. These images may be used to determine fractional snow cover as winter arrives, for comparison with the albedo that can be calculated from downward-looking radiometers, as well as some indication of present weather. Similarly, during spring time, the camera images show the changes in the ground albedo as the snow melts. The tower images are saved in hourly intervals. In addition, two other cameras, the skydeck camera in Barrow and the piling camera in Atqasuk, show the current conditions at those sites.

Moudry, D

2005-01-01

378

Image Size Range and TV Camera Separation Distances for Large Secure Areas.  

National Technical Information Service (NTIS)

Closed circuit TV cameras frequently are outfitted with short focal length lenses to display terrain near the camera to a security guard. This method of employment causes three human factors problems: (1) usable range over which intruders are detectable a...

H. C. Self

1982-01-01

379

Evaluation of a CdTe semiconductor based compact gamma camera for sentinel lymph node imaging  

SciTech Connect

Purpose: The authors assembled a prototype compact gamma-ray imaging probe (MediPROBE) for sentinel lymph node (SLN) localization. This probe is based on a semiconductor pixel detector. Its basic performance was assessed in the laboratory and clinically in comparison with a conventional gamma camera. Methods: The room-temperature CdTe pixel detector (1 mm thick) has 256x256 square pixels arranged with a 55 {mu}m pitch (sensitive area 14.08x14.08 mm{sup 2}), coupled pixel-by-pixel via bump-bonding to the Medipix2 photon-counting readout CMOS integrated circuit. The imaging probe is equipped with a set of three interchangeable knife-edge pinhole collimators (0.94, 1.2, or 2.1 mm effective diameter at 140 keV) and its focal distance can be regulated in order to set a given field of view (FOV). A typical FOV of 70 mm at 50 mm skin-to-collimator distance corresponds to a minification factor 1:5. The detector is operated at a single low-energy threshold of about 20 keV. Results: For {sup 99m}Tc, at 50 mm distance, a background-subtracted sensitivity of 6.5x10{sup -3} cps/kBq and a system spatial resolution of 5.5 mm FWHM were obtained for the 0.94 mm pinhole; corresponding values for the 2.1 mm pinhole were 3.3x10{sup -2} cps/kBq and 12.6 mm. The dark count rate was 0.71 cps. Clinical images in three patients with melanoma indicate detection of the SLNs with acquisition times between 60 and 410 s with an injected activity of 26 MBq {sup 99m}Tc and prior localization with standard gamma camera lymphoscintigraphy. Conclusions: The laboratory performance of this imaging probe is limited by the pinhole collimator performance and the necessity of working in minification due to the limited detector size. However, in clinical operative conditions, the CdTe imaging probe was effective in detecting SLNs with adequate resolution and an acceptable sensitivity. Sensitivity is expected to improve with the future availability of a larger CdTe detector permitting operation at shorter distances from the patient skin.

Russo, Paolo; Curion, Assunta S.; Mettivier, Giovanni; Esposito, Michela; Aurilio, Michela; Caraco, Corradina; Aloj, Luigi; Lastoria, Secondo [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II, I-80126 Napoli (Italy) and Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, I-80126 Napoli (Italy); Medicina Nucleare, Istituto Nazionale per lo Studio e la Cura dei Tumori, Fondazione G. Pascale, I-80131 Napoli (Italy)

2011-03-15

380

Electronic Still Camera.  

National Technical Information Service (NTIS)

A handheld, programmable, digital camera is disclosed that supports a variety of sensors and has program control over the system components to provide versatility. The camera uses a high performance design which produces near film quality images from an e...

S. D. Holland

1992-01-01

381

A Holographic Motion Picture Camera.  

National Technical Information Service (NTIS)

A holographic motion picture camera for producing three dimensional images was disclosed. The camera employs an elliptical optical system and a motion compensator is present in one of the beam paths; the compensator allows the camera to photograph fast mo...

R. L. Kurtz

1974-01-01

382

The social camera: a case-study in contextual image recommendation  

Microsoft Academic Search

The digital camera revolution has changed the world of photography and now most people have access to, and even regularly carry, a digital camera. Often these cameras have been designed with simplicity in mind: they harness a variety of sophisticated technologies in order to automatically take care of all manner of complex settings (aperture, shutter speed, flash etc.) for point-and-shoot

Steven Bourke; Kevin McCarthy; Barry Smyth

2011-01-01

383

HERSCHEL/SCORE, imaging the solar corona in visible and EUV light: CCD camera characterization.  

PubMed

The HERSCHEL (helium resonant scattering in the corona and heliosphere) experiment is a rocket mission that was successfully launched last September from White Sands Missile Range, New Mexico, USA. HERSCHEL was conceived to investigate the solar corona in the extreme UV (EUV) and in the visible broadband polarized brightness and provided, for the first time, a global map of helium in the solar environment. The HERSCHEL payload consisted of a telescope, HERSCHEL EUV Imaging Telescope (HEIT), and two coronagraphs, HECOR (helium coronagraph) and SCORE (sounding coronagraph experiment). The SCORE instrument was designed and developed mainly by Italian research institutes and it is an imaging coronagraph to observe the solar corona from 1.4 to 4 solar radii. SCORE has two detectors for the EUV lines at 121.6 nm (HI) and 30.4 nm (HeII) and the visible broadband polarized brightness. The SCORE UV detector is an intensified CCD with a microchannel plate coupled to a CCD through a fiber-optic bundle. The SCORE visible light detector is a frame-transfer CCD coupled to a polarimeter based on a liquid crystal variable retarder plate. The SCORE coronagraph is described together with the performances of the cameras for imaging the solar corona. PMID:20428852

Pancrazzi, M; Focardi, M; Landini, F; Romoli, M; Fineschi, S; Gherardi, A; Pace, E; Massone, G; Antonucci, E; Moses, D; Newmark, J; Wang, D; Rossi, G

2010-04-29

384

Examination of the semi-automatic calculation technique of vegetation cover rate by digital camera images.  

NASA Astrophysics Data System (ADS)

The rice is one of the staple foods in the world High quality rice production requires periodically collecting rice growth data to control the growth of rice The height of plant the number of stem the color of leaf is well known parameters to indicate rice growth Rice growth diagnosis method based on these parameters is used operationally in Japan although collecting these parameters by field survey needs a lot of labor and time Recently a laborsaving method for rice growth diagnosis is proposed which is based on vegetation cover rate of rice Vegetation cover rate of rice is calculated based on discriminating rice plant areas in a digital camera image which is photographed in nadir direction Discrimination of rice plant areas in the image was done by the automatic binarization processing However in the case of vegetation cover rate calculation method depending on the automatic binarization process there is a possibility to decrease vegetation cover rate against growth of rice In this paper a calculation method of vegetation cover rate was proposed which based on the automatic binarization process and referred to the growth hysteresis information For several images obtained by field survey during rice growing season vegetation cover rate was calculated by the conventional automatic binarization processing and the proposed method respectively And vegetation cover rate of both methods was compared with reference value obtained by visual interpretation As a result of comparison the accuracy of discriminating rice plant areas was increased by the proposed

Takemine, S.; Rikimaru, A.; Takahashi, K.

385

The automatic image analysis of red blood cell deformability and blood flow in microchannels with an image-intensified high-speed video camera system  

Microsoft Academic Search

It is crucial in microcirculatory investigation to evaluate red blood cell (RBC) deformability. However, there are almost limited information and indirect method of analyses. The authors tried to measure RBC deformability automatically by a combination of a newly developed algorithm and recording of individual RBC images clearly with an image-intensified high-speed video camera system. The length and the diameter of

T. Shimizu; E. Sekizuka; C. Oshio; K. Tsukada; T. Nagai; R. Hokari; H. Minamitani

1998-01-01

386

Rotating slit image camera TOPCON SL 45. New developments for simultaneous image acquisition by photographic and CCD-assisted on-line documentation.  

PubMed

In a first approach the photographic camera part of the SL 45 B has been replaced by a CCD camera (2/3" black-and-white camera/Teli CS 3440 CCD B/W Tokyo Electronic Industry Co., Ltd.) unit thus enabling direct image acquisition and computer assisted analyses. Images have a full length of 8.8 mm. The images can be taken with only the observation light, no flash is necessary. Thus, the images can also be recorded on a VCR performing a complete rotation of the slit and all lens sections can be monitored obtaining almost three-dimensional information about the lens transparency/cataract formation. The further improvement is the on-line imaging for all SL-45 cameras in having CCD acquisition together with the usual 35-mm film photography. This is very important for the documentation of the lens coloration and for measuring lens fluorescence. For this TOPCON SL 45 (new generation) we are using the '2nd Scheimpflug condition' located within the eye piece of a SL 45 which is taken with a CS b/w No. 8310 C (Tokyo Electronic Industry Co., Ltd.). It is possible to integrate the CCD system in all TOPCON SL 45 Cameras (1st and 2nd production charge as well as SL 45 B). PMID:8883096

Dragomirescu, V; Hockwin, O

1996-01-01

387

Image processing module for high-speed thermal camera with cooled detector  

NASA Astrophysics Data System (ADS)

Infrared cameras are used in various military applications for early detection and observation. In applications where very fast image acquisition is needed the so called cooled detectors are used. Cooled detectors are a kind of detectors that demands cryogenic cooling, but in return provide exceptional performance and temperature sensitivity with low integration times. These features predestinate cooled detectors for special purposes like airborne systems, where fast and precise infrared radiation measurement is needed. Modern infrared cooled detector arrays like HgCdTe Epsilon detector from Sofradir with spectral range of 3.5?m-5?m can provide high frame rate reaching 140Hz with full frame readout. Increasing frame rates of cooled infrared detectors demands fast and efficient image processing modules for necessary operations like nonuniformity correction, bad pixel replacement and visualization. For that kind of detector array a fast image processing module was developed. The module is made of two separate FPGA modules and configuration processor. One FPGA was responsible for infrared data processing, and was performing nonuniformity correction, bad pixel replacement, linear and nonlinear filtering in spatial domain and dynamic range compression. Second FPGA was responsible for interfacing infrared data stream to standard video interfaces. It was responsible for frame rate conversion, image scaling and interpolation, and controlling ASICs for video interface realization. Both FPGAs use several external resources like SRAM and DRAM memories. The input interface was developed to connect with Epsilink board which is a standard proximity board provided by Sofradir for this kind of detector. The image processing chain is capable of performing real-time processing on data stream of volume up to about 40 Megapixels per second.

Bieszczad, Grzegorz; Sosnowski, Tomasz; Madura, Henryk; Kastek, Mariusz; Bare?a, Jaros?aw

2011-05-01

388

Calibration and Validation of Images from the Mars Reconnaissance Orbiter Mars Color Imager (MARCI) and Context Camera (CTX) Instruments  

NASA Astrophysics Data System (ADS)

The MRO CTX instrument is a monochrome (611±189; nm), linear array CCD pushbroom camera with a nominal surface resolution of 6 m/pixel. The MARCI instrument is a 2-D CCD framing camera with 5 visible (420, 550, 600, 650, and 720 nm) and 2 UV (260 and 320 nm) filters, a 180° field of view, and a nominal resolution of about 1 km/pixel at nadir. Following Mars Orbital Insertion (MOI) in March 2006, CTX and MARCI images were acquired for initial instrument checkouts and validation of the pre-flight and in-flight calibration pipeline. CTX in-flight bias and dark current levels are derived from masked pixels at the edges of the array. A dark current model derived during pre-flight calibration is applied if the masked pixels exhibit a gradient across the field or noise above an acceptable threshold. The CTX flatfield removes residual pixel non-uniformities and a subtle ''jail bar'' effect caused by the CCD's alternating register readout. Radiances are derived from bias, dark, and flat-corrected images using pre-flight scaling factors. Dividing the average radiances by the solar spectral radiance convolved over the CTX filter transmission and applying a Minnaert phase angle correction yields an average I/F level in the CTX post-MOI Mars images near an expected value of 0.2. Bias and dark current subtraction of the MARCI images uses either a pre-flight model or dark sky data from the far left or far right parts of the field (nominally off the Mars limb). The preflight flatfield data were modified based on in-flight performance to remove residual non-pixel uniformities. Some residual pixel-dependent bias nonuniformities were also corrected using in-flight data. Bias, dark, and flat-corrected images were converted to radiance using pre-flight scaling factors. Phase-corrected 7-filter I/F values for the region of Mars imaged during the post-MOI campaign are consistent with previous data.

Schaeffer, Derek; Bell, J. F., III; Malin, M.; Caplinger, M.; Calvin, W. M.; Cantor, B.; Clancy, R. T.; Haberle, R. M.; James, P. B.; Lee, S.; Thomas, P.; Wolff, M. J.

2006-09-01

389

Image processing algorithms to facilitate and enhance sentinel node detection using a hand-held gamma ray camera in surgical breast cancer staging  

Microsoft Academic Search

We have developed a miniature scintillation camera to be used in surgical cancer staging. The availability of such a compact hand-held gamma camera may in certain cases improve localization of the sentinel lymph node and reduce the duration of a surgical breast cancer staging procedure. We have investigated image processing algorithms applied to planar images that may improve node detection

Peter D. Olcott; Craig S. Levin

2006-01-01

390

Techniques for Optimising Data From Thermal Imaging Cameras on Active Volcanoes and Implications for Modelling Lava Flows  

Microsoft Academic Search

Following a systematic series of laboratory experiments using different thermal imaging cameras, it is now possible to determine surface temperatures of volcanic rocks in the laboratory over a range of temperatures and viewing angles with a precision of 0.8%. Extracting useful temperature data in the field is more challenging. Current methods of dealing with pixel integrated temperatures make assumptions that

H. Pinkerton; M. Ball; M. James; K. Cashman

2005-01-01

391

Cerebral Imaging Using exp 68 Ga Dtpa and the U.C.S.F. Multiwire Proportional Chamber Positron Camera.  

National Technical Information Service (NTIS)

A multiwire proportional chamber positron camera consisting of four 48 x 48 cm exp 2 detectors linked to a small digital computer has been designed, constructed, and characterized. Initial clinical application to brain imaging using exp 68 Ga DTPA in 10 p...

R. S. Hattner C. B. Lim S. J. Swann L. Kaufman V. Perez-Mendez

1975-01-01

392

Miniature, vacuum compatible 1024 (times) 1024 CCD camera for x-ray, ultra-violet, or optical imaging.  

National Technical Information Service (NTIS)

We have developed a very compact (60 (times) 60 (times) 75 mm(sup 3)), vacuum compatible, large format (25 (times) 25 mm(sup 2), 1024 (times) 1024 pixels) CCD camera for digital imaging of visible and ultraviolet radiation, soft to penetrating x-rays ((= ...

A. D. Conder J. Dunn B. K. F. Young

1994-01-01

393

CCD Camera  

DOEpatents

A CCD camera capable of observing a moving object which has varying intensities of radiation eminating therefrom and which may move at varying speeds is shown wherein there is substantially no overlapping of successive images and wherein the exposure times and scan times may be varied independently of each other.

Roth, Roger R. (Minnetonka, MN)

1983-01-01

394

CCD Camera  

DOEpatents

A CCD camera capable of observing a moving object which has varying intensities of radiation emanating therefrom and which may move at varying speeds is shown wherein there is substantially no overlapping of successive images and wherein the exposure times and scan times may be varied independently of each other. 7 figs.

Roth, R.R.

1983-08-02

395

Curiosity's Cameras  

NASA Video Gallery

Curiosity is at Point Lake on Mars and will snap pictures to send home. Find out more about the rover's 17 cameras, including why some shoot in color and others others take black-and-white images.Credit: NASA/JPL-Caltech › Curiosity's mission site

Luis Espinoza

2013-06-13

396

Dual-camera enabled real-time three-dimensional integral imaging pick-up and display.  

PubMed

A new real-time integral imaging pick-up and display method is demonstrated. This proposed method utilizes the dual-camera optical pick-up part to collect 3D information of real scene in real-time without pre-calibration. Elemental images are then provided by a computer-generated integral imaging part and displayed by a projection-type integral imaging display part. The theoretical analysis indicates the method is robust to the camera position deviation, which profits the real-time data processing. Experimental results show that the fully continuous, real 3D scene pick-up and display system is feasible with a throughput of 8 fps in real time. Further analysis predicts that the parallel optimization can be adopted by the proposed method for real-time 3D pick-up and display with a throughput of 25 fps. PMID:23262680

Jiao, Xiaoxue; Zhao, Xing; Yang, Yong; Fang, Zhiliang; Yuan, Xiaocong

2012-12-01

397

Photometric-based recovery of illuminant-free color images using a red-green-blue digital camera  

NASA Astrophysics Data System (ADS)

Albedo estimation has traditionally been used to make computational simulations of real objects under different conditions, but as yet no device is capable of measuring albedo directly. The aim of this work is to introduce a photometric-based color imaging framework that can estimate albedo and can reproduce the appearance both indoors and outdoors of images under different lights and illumination geometry. Using a calibration sample set composed of chips made of the same material but different colors and textures, we compare two photometric-stereo techniques, one of them avoiding the effect of shadows and highlights in the image and the other ignoring this constraint. We combined a photometric-stereo technique and a color-estimation algorithm that directly relates the camera sensor outputs with the albedo values. The proposed method can produce illuminant-free images with good color accuracy when a three-channel red-green-blue (RGB) digital camera is used, even outdoors under solar illumination.

Luis Nieves, Juan; Plata, Clara; Valero, Eva M.; Romero, Javier

2012-01-01

398

Studies of the anodic dissolution of aluminium alloys containing tin and gallium using imaging with a high-speed camera  

Microsoft Academic Search

Imaging with a high-speed camera at a resolution of 10–20?m has been used for the direct observation of the anodic dissolution of aluminium alloys containing Sn and Ga. The imaging allows confirmation that hydrogen bubble evolution occurs from the Sn inclusions within rounded pits during both open circuit corrosion and anodic dissolution. Using microelectrodes with only a few Sn inclusions

Peter R. Birkin; Maria Nestoridi; Derek Pletcher

2009-01-01

399

Development of a pixelated GSO gamma camera system with tungsten parallel hole collimator for single photon imaging  

SciTech Connect

Purpose: In small animal imaging using a single photon emitting radionuclide, a high resolution gamma camera is required. Recently, position sensitive photomultiplier tubes (PSPMTs) with high quantum efficiency have been developed. By combining these with nonhygroscopic scintillators with a relatively low light output, a high resolution gamma camera can become useful for low energy gamma photons. Therefore, the authors developed a gamma camera by combining a pixelated Ce-doped Gd{sub 2}SiO{sub 5} (GSO) block with a high quantum efficiency PSPMT. Methods: GSO was selected for the scintillator, because it is not hygroscopic and does not contain any natural radioactivity. An array of 1.9 mm x 1.9 mm x 7 mm individual GSO crystal elements was constructed. These GSOs were combined with a 0.1-mm thick reflector to form a 22 x 22 matrix and optically coupled to a high quantum efficiency PSPMT (H8500C-100 MOD8). The GSO gamma camera was encased in a tungsten gamma-ray shield with tungsten pixelated parallel hole collimator, and the basic performance was measured for Co-57 gamma photons (122 keV). Results: In a two-dimensional position histogram, all pixels were clearly resolved. The energy resolution was {approx}15% FWHM. With the 20-mm thick tungsten pixelated collimator, the spatial resolution was 4.4-mm FWHM 40 mm from the collimator surface, and the sensitivity was {approx}0.05%. Phantom and small animal images were successfully obtained with our developed gamma camera. Conclusions: These results confirmed that the developed pixelated GSO gamma camera has potential as an effective instrument for low energy gamma photon imaging.

Yamamoto, S.; Watabe, H.; Kanai, Y.; Shimosegawa, E.; Hatazawa, J. [Kobe City College of Technology, 8-3 Gakuen-Higashi-machi, Nishi-ku, Kobe 651-2194 (Japan); Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan); Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan); Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan) and Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan)

2012-02-15

400

Prompt gamma imaging with a slit camera for real-time range control in proton therapy  

NASA Astrophysics Data System (ADS)

Treatments delivered by proton therapy are affected by uncertainties on the range of the beam within the patient, requiring medical physicists to add safety margins on the penetration depth of the beam. To reduce these margins and deliver safer treatments, different projects are currently investigating real-time range control by imaging prompt gammas emitted along the proton tracks in the patient. This study reports on the feasibility, development and test of a new concept of prompt gamma camera using a slit collimator to obtain a one-dimensional projection of the beam path on a scintillation detector. This concept was optimized, using the Monte Carlo code MCNPX version 2.5.0, to select high energy photons correlated with the beam range and detect them with both high statistics and sufficient spatial resolution. To validate the Monte Carlo model, spectrometry measurements of secondary particles emitted by a PMMA target during proton irradiation at 160 MeV were realized. An excellent agreement with the simulations was observed when using subtraction methods to isolate the gammas in direct incidence. A first prototype slit camera using the HiCam gamma detector was consequently prepared and tested successfully at 100 and 160 MeV beam energies. Results confirmed the potential of this concept for real-time range monitoring with millimetre accuracy in pencil beam scanning mode for typical clinical conditions. If we neglect electronic dead times and rejection of detected events, the current solution with its collimator at 15 cm from the beam axis can achieve a 1-2 mm standard deviation on range estimation in a homogeneous PMMA target for numbers of protons that correspond to doses in water at the Bragg peak as low as 15 cGy at 100 MeV and 25 cGy at 160 MeV assuming pencil beams with a Gaussian profile of 5 mm sigma at target entrance.

Smeets, J.; Roellinghoff, F.; Prieels, D.; Stichelbaut, F.; Benilov, A.; Busca, P.; Fiorini, C.; Peloso, R.; Basilavecchia, M.; Frizzi, T.; Dehaes, J. C.; Dubus, A.

2012-06-01

401

Radioisotope guided surgery with imaging probe, a hand-held high-resolution gamma camera  

NASA Astrophysics Data System (ADS)

Since 1997, our group of Physics together with Nuclear Physicians studies imaging probes (IP), hand-held, high-resolution gamma cameras for radio-guided surgery (RGS). Present work is aimed to verify the usefulness of two updated IP in different surgical operations. Forty patients scheduled for breast cancer sentinel node (SN) biopsy, five patients with nodal recurrence of thyroid cancer, seven patients with parathyroid adenomas, five patients with neuroendocrine tumours (NET), were operated under the guide of IP. We used two different IP with field of view of 1 and 4 in.2, respectively and intrinsic spatial resolution of about 2 mm. Radioisotopes were 99mTc, 123I and 111In. The 1 in.2 IP detected SN in all the 40 patients and more than one node in 24, whereas anger camera (AC) failed locating SN in four patients and detected true positive second nodes in only nine patients. The 4 in.2 IP was used for RGS of thyroid, parathyroid and NETs. It detected eight latero-cervical nodes. In the same patients, AC detected five invaded nodes. Parathyroid adenomas detected by IP were 10 in 7 patients, NET five in five patients. One and 4 in.2 IPs showed usefulness in all operations. Initial studies on SN biopsy were carried out on small series of patients to validate IP and to demonstrate the effectiveness and usefulness of IP alone or against conventional probes. We propose the use of the IP as control method for legal documentation and surgeon strategy guide before and after lesion(s) removal.

Soluri, A.; Trotta, C.; Scopinaro, F.; Tofani, A.; D'Alessandria, C.; Pasta, V.; Stella, S.; Massari, R.

2007-12-01

402

TRIDENT: An Infrared Differential Imaging Camera Optimized for the Detection of Methanated Substellar Companions  

NASA Astrophysics Data System (ADS)

We describe a near-infrared camera in use at the Canada-France-Hawaii Telescope (CFHT) and at the 1.6 m telescope of the Observatoire du mont Mégantic (OMM). The camera is based on a Hawaii-1 1024 × 1024 HgCdTe array detector. Its main feature is the acquisition of three simultaneous images at three wavelengths across the methane absorption bandhead at 1.6 ?m, enabling, in theory, an accurate subtraction of the stellar point-spread function (PSF) and the detection of faint close, methanated companions. The instrument has no coronagraph and features fast data acquisition, yielding high observing efficiency on bright stars. The performance of the instrument is described, and it is illustrated by laboratory tests and CFHT observations of the nearby stars GL 526, ? And, and ? And. TRIDENT can detect (6 ?) a methanated companion with ?H=9.5 at 0.5" separation from the star in 1 hr of observing time. Non-common-path aberrations and amplitude modulation differences between the three optical paths are likely to be the limiting factors preventing further PSF attenuation. Instrument rotation and reference-star subtraction improve the detection limit by a factor of 2 and 4, respectively. A PSF noise attenuation model is presented to estimate the non-common-path wave-front difference effect on PSF subtraction performance. Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council of Canada, the Institut National des Science de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

Marois, Christian; Doyon, René; Nadeau, Daniel; Racine, René; Riopel, Martin; Vallée, Philippe; Lafrenière, David

2005-07-01

403

An analytical image reconstruction algorithm to compensate for scattering angle broadening in Compton cameras.  

PubMed

Compton cameras have been developed for use in gamma-ray astronomy and nuclear medicine. Their defining merit is that they do not need collimators; however, on the demerit side, they need inversion procedures for image reconstruction, since a measured datum is proportional to the integration of incident gamma rays along a cone surface with the same Compton scattering angle. First, an iteration method was adopted for this task. Later, analytical methods were found under restricted conditions. Parra (2000 IEEE Trans. Nucl. Sci. 47 1543-50) deduced a purely analytical reconstruction algorithm for a complete set of scattering-projection data that include data at all the scattering angles. Tomitani and Hirasawa (2002 Phys. Med. Biol. 47 2129-45) found that by making a slight modification, Parra's algorithm could be extended to the scattering-projection data in limited scattering angles. However, their algorithm neglected the effects of practical problems that cause the degradation of spatial resolution. Sources of degradation were identified as noise in the energy signal of their front detector and the Doppler effect in the scattering process. In this paper, we first analyse the effects of these sources on the angular resolution of the scattering-projection data and then present a revised reconstruction algorithm in which these two factors are incorporated. Simulation studies on digital phantoms reveal that the algorithm can reconstruct images even when these two factors are included. PMID:12741498

Hirasawa, M; Tomitani, T

2003-04-21

404

4 Vesta in Color: High Resolution Mapping from Dawn Framing Camera Images  

NASA Astrophysics Data System (ADS)

Rotational surface variations on asteroid 4 Vesta have been known from ground-based and HST observations, and they have been interpreted as evidence of compositional diversity. NASA's Dawn mission entered orbit around Vesta on July 16, 2011 for a yearlong global characterization. The framing cameras (FC) onboard the Dawn spacecraft will image the asteroid in one clear (broad) and seven narrow band filters covering the wavelength range between 0.4-1.0 ?m. We present color mapping results from the Dawn FC observations of Vesta obtained during Survey orbit (~3000 km) and High-Altitude Mapping Orbit (HAMO) (~950 km). Our aim is to create global color maps of Vesta using multi spectral FC images to identify the spatial extent of compositional units and link them with other available data sets to extract the basic mineralogy. While the VIR spectrometer onboard Dawn has higher spectral resolution (864 channels) allowing precise mineralogical assessment of Vesta's surface, the FC has three times higher spatial resolution in any given orbital phase. In an effort to extract maximum information from FC data we have developed algorithms using laboratory spectra of pyroxenes and HED meteorites to derive parameters associated with the 1-micron absorption band wing. These parameters will help map the global distribution of compositionally related units on Vesta's surface. Interpretation of these units will involve the integration of FC and VIR data.

Reddy, V.; Le Corre, L.; Nathues, A.; Sierks, H.; Christensen, U. R.; Hoffmann, M.; Schroeder, S.; Vincent, J.; McSween, H. Y.; Denevi, B. W.; Li, J.; Pieters, C. M.; Gaffey, M.; Mittlefehldt, D. W.; Buratti, B. J.; Hicks, M.; McCord, T. B.; Combe, J.; DeSanctis, C.; Russell, C. T.; Raymond, C. A.; Gutierrez-Marques, P.; Maue, T.; Hall, I.

2011-12-01

405

Fast generation of hologram from range camera images based on the sub-lines and holographic interpolation  

NASA Astrophysics Data System (ADS)

The intensity image and the depth images of a three-dimensional object scene can be captured with a commodity range camera, and converted into a Fresnel hologram. However, for some cameras, the images are subject to radial distortion, and too small to be visible in optical reconstruction. Moreover, the conventional hologram generation process with numerical means is significant. In this paper, we present a fast method to overcome the above-mentioned problems. First, the intensity and the depth images are transformed to reduce the radial distortion. Next, the images are interpolated horizontally, and converted into a sequence of sub-lines. Finally, the sub-lines are swiftly converted into a Fresnel hologram through padding along the vertical direction. The pair of interpolation process effectively increases the size and visibility of the reconstructed image. Although our method can be applied to different kinds of range cameras, we have selected the Swissranger model as a showcase to demonstrate the feasibility of the approach.

Tsang, Peter; Situ, W. C.; Situ, W. C.; Cheung, W.-K.; Poon, T.-C.; Zhou, Changhe

2012-11-01

406

Dual-wavelength laser speckle imaging to simultaneously access blood flow, blood volume, and oxygenation using a color CCD camera.  

PubMed

We developed a dual-wavelength laser speckle imaging system using a single industrial-grade color CCD camera with Bayer filters to simultaneously image changes in blood flow, blood volume, and oxygenation. One frame of a color image recorded with dual-wavelength laser illumination provides not only the intensity fluctuation of the speckle pattern, but also the dual-wavelength optical reflectance signal. The method was validated using a tissue phantom and cuff ischemia experiments in the human arm. This system achieves complete time synchronization, unlike conventional time-sharing systems. Compared with a multicamera system, it also avoids the problem of image registration and can be less expensive. PMID:24104848

Wang, Jia; Wang, Yaru; Li, Bing; Feng, Danqi; Lu, Jinling; Luo, Qingming; Li, Pengcheng

2013-09-15

407

Stereoscopic cameras for the real-time acquisition of panoramic 3D images and videos  

Microsoft Academic Search

There are different panoramic techniques to produce outstanding stereoscopic panoramas of static scenes. However, a camera configuration capable to capture omnidirectional stereoscopic snapshots and videos of dynamic scenes is still a subject of research. In this paper, two multiple-camera configurations capable to produce high-quality stereoscopic panoramas in real-time are presented. Unlike existing methods, the proposed multiple-camera systems acquire all the

Luis E. Gurrieri; E. Dubois

2013-01-01

408

Strong-Lensing Analysis of A1689 from Deep Advanced Camera Images  

NASA Astrophysics Data System (ADS)

We analyze deep multicolor Advanced Camera images of the largest known gravitational lens, A1689. Radial and tangential arcs delineate the critical curves in unprecedented detail, and many small counterimages are found near the center of mass. We construct a flexible light deflection field to predict the appearance and positions of counterimages. The model is refined as new counterimages are identified and incorporated to improve the model, yielding a total of 106 images of 30 multiply lensed background galaxies, spanning a wide redshift range, 1.0images are reproduced well by our best-fitting lens model.

Broadhurst, Tom; Benítez, Narciso; Coe, Dan; Sharon, Keren; Zekser, Kerry; White, Rick; Ford, Holland; Bouwens, Rychard; Blakeslee, John; Clampin, Marc; Cross, Nick; Franx, Marijn; Frye, Brenda; Hartig, George; Illingworth, Garth; Infante, Leopoldo; Menanteau, Felipe; Meurer, Gerhardt; Postman, Marc; Ardila, D. R.; Bartko, F.; Brown, R. A.; Burrows, C. J.; Cheng, E. S.; Feldman, P. D.; Golimowski, D. A.; Goto, T.; Gronwall, C.; Herranz, D.; Holden, B.; Homeier, N.; Krist, J. E.; Lesser, M. P.; Martel, A. R.; Miley, G. K.; Rosati, P.; Sirianni, M.; Sparks, W. B.; Steindling, S.; Tran, H. D.; Tsvetanov, Z. I.; Zheng, W.

2005-03-01

409

A high resolution Small Field Of View (SFOV) gamma camera: a columnar scintillator coated CCD imager for medical applications  

NASA Astrophysics Data System (ADS)

We describe a high resolution, small field of view (SFOV), Charge Coupled Device (CCD) based camera for imaging small volumes of radionuclide uptake in tissues. The Mini Gamma Ray Camera (MGRC) is a collimated, scintillator-coated, low cost, high performance imager using low noise CCDs. The prototype MGRC has a 600 ?m thick layer of columnar CsI(Tl) and operates in photon counting mode using a thermoelectric cooler to achieve an operating temperature of - 10°C. Collimation was performed using a pin hole collimator. We have measured the spatial resolution, energy resolution and efficiency using a number of radioisotope sources including 140 keV gamma-rays from 99mTc in a specially designed phantom. We also describe our first imaging of a volunteer patient.

Lees, J. E.; Bassford, D. J.; Blake, O. E.; Blackshaw, P. E.; Perkins, A. C.

2011-12-01

410

Simultaneously capturing real-time images in two emission channels using a dual camera emission splitting system: applications to cell adhesion.  

PubMed

Multi-color immunofluorescence microscopy to detect specific molecules in the cell membrane can be coupled with parallel plate flow chamber assays to investigate mechanisms governing cell adhesion under dynamic flow conditions. For instance, cancer cells labeled with multiple fluorophores can be perfused over a potentially reactive substrate to model mechanisms of cancer metastasis. However, multi-channel single camera systems and color cameras exhibit shortcomings in image acquisition for real-time live cell analysis. To overcome these limitations, we used a dual camera emission splitting system to simultaneously capture real-time image sequences of fluorescently labeled cells in the flow chamber. Dual camera emission splitting systems filter defined wavelength ranges into two monochrome CCD cameras, thereby simultaneously capturing two spatially identical but fluorophore-specific images. Subsequently, psuedocolored one-channel images are combined into a single real-time merged sequence that can reveal multiple target molecules on cells moving rapidly across a region of interest. PMID:24056855

Carlson, Grady E; Martin, Eric W; Burdick, Monica M

2013-09-04

411

Miniature, vacuum compatible 1024 {times} 1024 CCD camera for x-ray, ultra-violet, or optical imaging  

SciTech Connect

We have developed a very compact (60 {times} 60 {times} 75 mm{sup 3}), vacuum compatible, large format (25 {times} 25 mm{sup 2}, 1024 {times} 1024 pixels) CCD camera for digital imaging of visible and ultraviolet radiation, soft to penetrating x-rays ({le}20 keV), and charged particles. This camera provides a suitable replacement for film with a linear response, dynamic range and intrinsic signal-to- noise response superior than current x-ray film, and provides real- time access to the data. The spatial resolution of the camera (< 25 {mu}m) is similar to typical digitization slit or step sizes used in processing film data. This new large format CCD camera has immediate applications as the recording device for steak cameras or gated microchannel plate diagnostic, or when used directly as the detector for x-ray, xuv, or optical signals. This is especially important in studying high-energy plasmas produced in pulse-power, ICF, and high powered laser-plasma experiments, as well as other medical and industrial applications.

Conder, A.D.; Dunn, J.; Young, B.K.F.

1994-05-01

412

Those Nifty Digital Cameras!  

ERIC Educational Resources Information Center

Describes digital photography--an electronic imaging technology that merges computer capabilities with traditional photography--and its uses in education. Discusses how a filmless camera works, types of filmless cameras, advantages and disadvantages, and educational applications of the consumer digital cameras. (AEF)

Ekhaml, Leticia

1996-01-01

413

The optimum Ga-67-citrate gamma camera imaging quality factors as first calculated and shown by the Taguchi's analysis.  

PubMed

In this work gallium-67 ((67)Ga) gamma camera imaging quality was optimized using the Taguchi's analysis and a planar phantom. The acrylic planar phantom was LASER-cut to form groups of slits 1mm wide and 5mm deep, to determine the spatial resolution and contrast ratio that could be achieved in a (67)Ga citrate nuclear medicine examination. The (67)Ga-citrate solution was injected into the slits to form an active radioactive line source which was placed between regular acrylic plates for optimization. Then, nine combinations of four operating factors: L9 (3((4)), of the gamma camera imaging system were used and followed the Taguchi's analysis. The four operating factors were: a) the type of collimator in front of the NaI(Tl) detector, b) the region of interest of (67)Ga gamma rays spectrum, c) the scanning speed of NaI(Tl) detector head and d) the activity of (67)Ga. The original judged grade of the planar phantom image quality was increased 36% and factors a) and b) were confirmed to dominate. The cross interaction among factors was also discussed. Our results showed that the optimal factor settings of the gamma camera imaging system were verified by performing a routine nuclear medicine examination in ten cases. Nine cases showed the same optimal settings as estimated by three highly trained radio-diagnostic physicians. Additionally, the optimal setting yielded clearer images with greater cont