Science.gov

Sample records for digital camera technology

  1. High Speed Digital Camera Technology Review

    NASA Technical Reports Server (NTRS)

    Clements, Sandra D.

    2009-01-01

    A High Speed Digital Camera Technology Review (HSD Review) is being conducted to evaluate the state-of-the-shelf in this rapidly progressing industry. Five HSD cameras supplied by four camera manufacturers participated in a Field Test during the Space Shuttle Discovery STS-128 launch. Each camera was also subjected to Bench Tests in the ASRC Imaging Development Laboratory. Evaluation of the data from the Field and Bench Tests is underway. Representatives from the imaging communities at NASA / KSC and the Optical Systems Group are participating as reviewers. A High Speed Digital Video Camera Draft Specification was updated to address Shuttle engineering imagery requirements based on findings from this HSD Review. This draft specification will serve as the template for a High Speed Digital Video Camera Specification to be developed for the wider OSG imaging community under OSG Task OS-33.

  2. Digital Cameras for Student Use.

    ERIC Educational Resources Information Center

    Simpson, Carol

    1997-01-01

    Describes the features, equipment and operations of digital cameras and compares three different digital cameras for use in education. Price, technology requirements, features, transfer software, and accessories for the Kodak DC25, Olympus D-200L and Casio QV-100 are presented in a comparison table. (AEF)

  3. Digital Pinhole Camera

    ERIC Educational Resources Information Center

    Lancor, Rachael; Lancor, Brian

    2014-01-01

    In this article we describe how the classic pinhole camera demonstration can be adapted for use with digital cameras. Students can easily explore the effects of the size of the pinhole and its distance from the sensor on exposure time, magnification, and image quality. Instructions for constructing a digital pinhole camera and our method for…

  4. 2010 A Digital Odyssey: Exploring Document Camera Technology and Computer Self-Efficacy in a Digital Era

    ERIC Educational Resources Information Center

    Hoge, Robert Joaquin

    2010-01-01

    Within the sphere of education, navigating throughout a digital world has become a matter of necessity for the developing professional, as with the advent of Document Camera Technology (DCT). This study explores the pedagogical implications of implementing DCT; to see if there is a relationship between teachers' comfort with DCT and to the…

  5. Recent advances in digital camera optics

    NASA Astrophysics Data System (ADS)

    Ishiguro, Keizo

    2012-10-01

    The digital camera market has extremely expanded in the last ten years. The zoom lens for digital camera is especially the key determining factor of the camera body size and image quality. Its technologies have been based on several analog technological progresses including the method of aspherical lens manufacturing and the mechanism of image stabilization. Panasonic is one of the pioneers of both technologies. I will introduce the previous trend in optics of zoom lens as well as original optical technologies of Panasonic digital camera "LUMIX", and in addition optics in 3D camera system. Besides, I would like to suppose the future trend in digital cameras.

  6. Digital Elevation Model from Non-Metric Camera in Uas Compared with LIDAR Technology

    NASA Astrophysics Data System (ADS)

    Dayamit, O. M.; Pedro, M. F.; Ernesto, R. R.; Fernando, B. L.

    2015-08-01

    Digital Elevation Model (DEM) data as a representation of surface topography is highly demanded for use in spatial analysis and modelling. Aimed to that issue many methods of acquisition data and process it are developed, from traditional surveying until modern technology like LIDAR. On the other hands, in a past four year the development of Unamend Aerial System (UAS) aimed to Geomatic bring us the possibility to acquire data about surface by non-metric digital camera on board in a short time with good quality for some analysis. Data collectors have attracted tremendous attention on UAS due to possibility of the determination of volume changes over time, monitoring of the breakwaters, hydrological modelling including flood simulation, drainage networks, among others whose support in DEM for proper analysis. The DEM quality is considered as a combination of DEM accuracy and DEM suitability so; this paper is aimed to analyse the quality of the DEM from non-metric digital camera on UAS compared with a DEM from LIDAR corresponding to same geographic space covering 4 km2 in Artemisa province, Cuba. This area is in a frame of urban planning whose need to know the topographic characteristics in order to analyse hydrology behaviour and decide the best place for make roads, building and so on. Base on LIDAR technology is still more accurate method, it offer us a pattern for test DEM from non-metric digital camera on UAS, whose are much more flexible and bring a solution for many applications whose needs DEM of detail.

  7. Cameras for digital microscopy.

    PubMed

    Spring, Kenneth R

    2013-01-01

    This chapter reviews the fundamental characteristics of charge-coupled devices (CCDs) and related detectors, outlines the relevant parameters for their use in microscopy, and considers promising recent developments in the technology of detectors. Electronic imaging with a CCD involves three stages--interaction of a photon with the photosensitive surface, storage of the liberated charge, and readout or measurement of the stored charge. The most demanding applications in fluorescence microscopy may require as much as four orders of greater magnitude sensitivity. The image in the present-day light microscope is usually acquired with a CCD camera. The CCD is composed of a large matrix of photosensitive elements (often referred to as "pixels" shorthand for picture elements, which simultaneously capture an image over the entire detector surface. The light-intensity information for each pixel is stored as electronic charge and is converted to an analog voltage by a readout amplifier. This analog voltage is subsequently converted to a numerical value by a digitizer situated on the CCD chip, or very close to it. Several (three to six) amplifiers are required for each pixel, and to date, uniform images with a homogeneous background have been a problem because of the inherent difficulties of balancing the gain in all of the amplifiers. Complementary metal oxide semiconductor sensors also exhibit relatively high noise associated with the requisite high-speed switching. Both of these deficiencies are being addressed, and sensor performance is nearing that required for scientific imaging. PMID:23931507

  8. Image Sensors Enhance Camera Technologies

    NASA Technical Reports Server (NTRS)

    2010-01-01

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

  9. Using Digital Cameras to Teach about Infrared Radiation and Instrumentation Technology

    NASA Astrophysics Data System (ADS)

    Pompea, S. M.; Croft, S. K.

    1998-12-01

    Digital cameras and image processing are used to create color composite images that illustrate the importance of the near infrared portion of the spectrum in providing additional information about an astronomical object. Demonstrations with digital cameras also help make infrared radiation real to students and illustrate the different aspects of a sensing system including the spectral emission properties of the source, the reflectivity of the object of interest, the use of filters, detector sensitivity, and the use of image processing. Using appropriate, easily available filters, students can demonstrate that two objects that appear green (such as a car and a plant) have very different properties in the near infrared, since chlorophyll in plants is reflective in the near IR. The results can be applied to imaging of the planets to look for chlorophyll features indicative of life. Digital cameras are affordable, relatively common devices which can be used in a wide variety of classroom and experimental settings. As such they can have a profound influence, in conjunction with image processing, on participatory teaching of observational astronomy and in sharing observations across the web. Some other general applications in this area as well as extensions to several areas of spectroscopy will also be discussed. This work was supported by an NSF instructional materials grant as part of the Astronomy Village: Investigating the Solar System development program. S. Pompea is an adjunct faculty member of Steward Observatory, University of Arizona.

  10. A Novel Multi-Digital Camera System Based on Tilt-Shift Photography Technology

    PubMed Central

    Sun, Tao; Fang, Jun-yong; Zhao, Dong; Liu, Xue; Tong, Qing-xi

    2015-01-01

    Multi-digital camera systems (MDCS) are constantly being improved to meet the increasing requirement of high-resolution spatial data. This study identifies the insufficiencies of traditional MDCSs and proposes a new category MDCS based on tilt-shift photography to improve ability of the MDCS to acquire high-accuracy spatial data. A prototype system, including two or four tilt-shift cameras (TSC, camera model: Nikon D90), is developed to validate the feasibility and correctness of proposed MDCS. Similar to the cameras of traditional MDCSs, calibration is also essential for TSC of new MDCS. The study constructs indoor control fields and proposes appropriate calibration methods for TSC, including digital distortion model (DDM) approach and two-step calibrated strategy. The characteristics of TSC are analyzed in detail via a calibration experiment; for example, the edge distortion of TSC. Finally, the ability of the new MDCS to acquire high-accuracy spatial data is verified through flight experiments. The results of flight experiments illustrate that geo-position accuracy of prototype system achieves 0.3 m at a flight height of 800 m, and spatial resolution of 0.15 m. In addition, results of the comparison between the traditional (MADC II) and proposed MDCS demonstrate that the latter (0.3 m) provides spatial data with higher accuracy than the former (only 0.6 m) under the same conditions. We also take the attitude that using higher accuracy TSC in the new MDCS should further improve the accuracy of the photogrammetry senior product. PMID:25835187

  11. A novel multi-digital camera system based on tilt-shift photography technology.

    PubMed

    Sun, Tao; Fang, Jun-Yong; Zhao, Dong; Liu, Xue; Tong, Qing-Xi

    2015-01-01

    Multi-digital camera systems (MDCS) are constantly being improved to meet the increasing requirement of high-resolution spatial data. This study identifies the insufficiencies of traditional MDCSs and proposes a new category MDCS based on tilt-shift photography to improve ability of the MDCS to acquire high-accuracy spatial data. A prototype system, including two or four tilt-shift cameras (TSC, camera model: Nikon D90), is developed to validate the feasibility and correctness of proposed MDCS. Similar to the cameras of traditional MDCSs, calibration is also essential for TSC of new MDCS. The study constructs indoor control fields and proposes appropriate calibration methods for TSC, including digital distortion model (DDM) approach and two-step calibrated strategy. The characteristics of TSC are analyzed in detail via a calibration experiment; for example, the edge distortion of TSC. Finally, the ability of the new MDCS to acquire high-accuracy spatial data is verified through flight experiments. The results of flight experiments illustrate that geo-position accuracy of prototype system achieves 0.3 m at a flight height of 800 m, and spatial resolution of 0.15 m. In addition, results of the comparison between the traditional (MADC II) and proposed MDCS demonstrate that the latter (0.3 m) provides spatial data with higher accuracy than the former (only 0.6 m) under the same conditions. We also take the attitude that using higher accuracy TSC in the new MDCS should further improve the accuracy of the photogrammetry senior product. PMID:25835187

  12. Measuring Distances Using Digital Cameras

    ERIC Educational Resources Information Center

    Kendal, Dave

    2007-01-01

    This paper presents a generic method of calculating accurate horizontal and vertical object distances from digital images taken with any digital camera and lens combination, where the object plane is parallel to the image plane or tilted in the vertical plane. This method was developed for a project investigating the size, density and spatial…

  13. Digital Camera Project Fosters Communication Skills

    ERIC Educational Resources Information Center

    Fisher, Ashley; Lazaros, Edward J.

    2009-01-01

    This article details the many benefits of educators' use of digital camera technology and provides an activity in which students practice taking portrait shots of classmates, manipulate the resulting images, and add language arts practice by interviewing their subjects to produce a photo-illustrated Word document. This activity gives…

  14. Replacing 16 mm film cameras with high definition digital cameras

    SciTech Connect

    Balch, K.S.

    1995-12-31

    For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne gun cameras, 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, 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 camera from Kodak that has been designed to replace 16 mm high speed film cameras.

  15. Teaching with Technology: Step Back and Hand over the Cameras! Using Digital Cameras to Facilitate Mathematics Learning with Young Children in K-2 Classrooms

    ERIC Educational Resources Information Center

    Northcote, Maria

    2011-01-01

    Digital cameras are now commonplace in many classrooms and in the lives of many children in early childhood centres and primary schools. They are regularly used by adults and teachers for "saving special moments and documenting experiences." The use of previously expensive photographic and recording equipment has often remained in the domain of…

  16. Digital security technology simplified.

    PubMed

    Scaglione, Bernard J

    2007-01-01

    Digital security technology is making great strides in replacing analog and other traditional security systems including CCTV card access, personal identification and alarm monitoring applications. Like any new technology, the author says, it is important to understand its benefits and limitations before purchasing and installing, to ensure its proper operation and effectiveness. This article is a primer for security directors on how digital technology works. It provides an understanding of the key components which make up the foundation for digital security systems, focusing on three key aspects of the digital security world: the security network, IP cameras and IP recorders. PMID:17907609

  17. Smart Camera Technology Increases Quality

    NASA Technical Reports Server (NTRS)

    2004-01-01

    When it comes to real-time image processing, everyone is an expert. People begin processing images at birth and rapidly learn to control their responses through the real-time processing of the human visual system. The human eye captures an enormous amount of information in the form of light images. In order to keep the brain from becoming overloaded with all the data, portions of an image are processed at a higher resolution than others, such as a traffic light changing colors. changing colors. In the same manner, image processing products strive to extract the information stored in light in the most efficient way possible. Digital cameras available today capture millions of pixels worth of information from incident light. However, at frame rates more than a few per second, existing digital interfaces are overwhelmed. All the user can do is store several frames to memory until that memory is full and then subsequent information is lost. New technology pairs existing digital interface technology with an off-the-shelf complementary metal oxide semiconductor (CMOS) imager to provide more than 500 frames per second of specialty image processing. The result is a cost-effective detection system unlike any other.

  18. Choosing the Best Digital Camera for Your Program

    ERIC Educational Resources Information Center

    Mikat, Richard P.; Anderson, Mandi

    2005-01-01

    Many educators in physical education, recreation, dance, and related fields have begun using digital images to enhance their teaching (e.g., Ryan, Marzilla, & Martindale, 2001). Many other educators would like to begin using this technology, but find the task of choosing an appropriate digital camera to be overwhelming. This article is designed to…

  19. An Inexpensive Digital Infrared Camera

    ERIC Educational Resources Information Center

    Mills, Allan

    2012-01-01

    Details are given for the conversion of an inexpensive webcam to a camera specifically sensitive to the near infrared (700-1000 nm). Some experiments and practical applications are suggested and illustrated. (Contains 9 figures.)

  20. Tips and Tricks for Digital Camera Users.

    ERIC Educational Resources Information Center

    Ekhaml, Leticia

    2002-01-01

    Discusses the use of digital cameras in school library media centers and offers suggestions for teachers and students in elementary schools. Describes appropriate image-editing software; explains how to create panoramas, screen savers, and coloring books; and includes useful tips for digital photographers. (LRW)

  1. Camera! Action! Collaborate with Digital Moviemaking

    ERIC Educational Resources Information Center

    Swan, Kathleen Owings; Hofer, Mark; Levstik, Linda S.

    2007-01-01

    Broadly defined, digital moviemaking integrates a variety of media (images, sound, text, video, narration) to communicate with an audience. There is near-ubiquitous access to the necessary software (MovieMaker and iMovie are bundled free with their respective operating systems) and hardware (computers with Internet access, digital cameras, etc.).…

  2. A stereoscopic lens for digital cinema cameras

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny; Rupkalvis, John

    2015-03-01

    Live-action stereoscopic feature films are, for the most part, produced using a costly post-production process to convert planar cinematography into stereo-pair images and are only occasionally shot stereoscopically using bulky dual-cameras that are adaptations of the Ramsdell rig. The stereoscopic lens design described here might very well encourage more live-action image capture because it uses standard digital cinema cameras and workflow to save time and money.

  3. National Guidelines for Digital Camera Systems Certification

    NASA Astrophysics Data System (ADS)

    Yaron, Yaron; Keinan, Eran; Benhamu, Moshe; Regev, Ronen; Zalmanzon, Garry

    2016-06-01

    Digital camera systems are a key component in the production of reliable, geometrically accurate, high-resolution geospatial products. These systems have replaced film imaging in photogrammetric data capturing. Today, we see a proliferation of imaging sensors collecting photographs in different ground resolutions, spectral bands, swath sizes, radiometric characteristics, accuracies and carried on different mobile platforms. In addition, these imaging sensors are combined with navigational tools (such as GPS and IMU), active sensors such as laser scanning and powerful processing tools to obtain high quality geospatial products. The quality (accuracy, completeness, consistency, etc.) of these geospatial products is based on the use of calibrated, high-quality digital camera systems. The new survey regulations of the state of Israel specify the quality requirements for each geospatial product including: maps at different scales and for different purposes, elevation models, orthophotographs, three-dimensional models at different levels of details (LOD) and more. In addition, the regulations require that digital camera systems used for mapping purposes should be certified using a rigorous mapping systems certification and validation process which is specified in the Director General Instructions. The Director General Instructions for digital camera systems certification specify a two-step process as follows: 1. Theoretical analysis of system components that includes: study of the accuracy of each component and an integrative error propagation evaluation, examination of the radiometric and spectral response curves for the imaging sensors, the calibration requirements, and the working procedures. 2. Empirical study of the digital mapping system that examines a typical project (product scale, flight height, number and configuration of ground control points and process). The study examine all the aspects of the final product including; its accuracy, the product pixels size

  4. Enviro-pix: Using Digital Cameras in the Classroom.

    ERIC Educational Resources Information Center

    Clements, Dan

    1997-01-01

    Provides technical information about digital photography including cost, quality, and applications in classrooms. Recommends that digital cameras be used for student classroom presentations and record keeping. (DDR)

  5. Classroom multispectral imaging using inexpensive digital cameras.

    NASA Astrophysics Data System (ADS)

    Fortes, A. D.

    2007-12-01

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

  6. Digital Earth Watch: Investigating the World with Digital Cameras

    NASA Astrophysics Data System (ADS)

    Gould, A. D.; Schloss, A. L.; Beaudry, J.; Pickle, J.

    2015-12-01

    Every digital camera including the smart phone camera can be a scientific tool. Pictures contain millions of color intensity measurements organized spatially allowing us to measure properties of objects in the images. This presentation will demonstrate how digital pictures can be used for a variety of studies with a special emphasis on using repeat digital photographs to study change-over-time in outdoor settings with a Picture Post. Demonstrations will include using inexpensive color filters to take pictures that enhance features in images such as unhealthy leaves on plants, or clouds in the sky. Software available at no cost from the Digital Earth Watch (DEW) website that lets students explore light, color and pixels, manipulate color in images and make measurements, will be demonstrated. DEW and Picture Post were developed with support from NASA. Please visit our websites: DEW: http://dew.globalsystemsscience.orgPicture Post: http://picturepost.unh.edu

  7. A digital ISO expansion technique for digital cameras

    NASA Astrophysics Data System (ADS)

    Yoo, Youngjin; Lee, Kangeui; Choe, Wonhee; Park, SungChan; Lee, Seong-Deok; Kim, Chang-Yong

    2010-01-01

    Market's demands of digital cameras for higher sensitivity capability under low-light conditions are remarkably increasing nowadays. The digital camera market is now a tough race for providing higher ISO capability. In this paper, we explore an approach for increasing maximum ISO capability of digital cameras without changing any structure of an image sensor or CFA. Our method is directly applied to the raw Bayer pattern CFA image to avoid non-linearity characteristics and noise amplification which are usually deteriorated after ISP (Image Signal Processor) of digital cameras. The proposed method fuses multiple short exposed images which are noisy, but less blurred. Our approach is designed to avoid the ghost artifact caused by hand-shaking and object motion. In order to achieve a desired ISO image quality, both low frequency chromatic noise and fine-grain noise that usually appear in high ISO images are removed and then we modify the different layers which are created by a two-scale non-linear decomposition of an image. Once our approach is performed on an input Bayer pattern CFA image, the resultant Bayer image is further processed by ISP to obtain a fully processed RGB image. The performance of our proposed approach is evaluated by comparing SNR (Signal to Noise Ratio), MTF50 (Modulation Transfer Function), color error ~E*ab and visual quality with reference images whose exposure times are properly extended into a variety of target sensitivity.

  8. X-ray imaging using digital cameras

    NASA Astrophysics Data System (ADS)

    Winch, Nicola M.; Edgar, Andrew

    2012-03-01

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

  9. Digital Camera Control for Faster Inspection

    NASA Technical Reports Server (NTRS)

    Brown, Katharine; Siekierski, James D.; Mangieri, Mark L.; Dekome, Kent; Cobarruvias, John; Piplani, Perry J.; Busa, Joel

    2009-01-01

    Digital Camera Control Software (DCCS) is a computer program for controlling a boom and a boom-mounted camera used to inspect the external surface of a space shuttle in orbit around the Earth. Running in a laptop computer in the space-shuttle crew cabin, DCCS commands integrated displays and controls. By means of a simple one-button command, a crewmember can view low- resolution images to quickly spot problem areas and can then cause a rapid transition to high- resolution images. The crewmember can command that camera settings apply to a specific small area of interest within the field of view of the camera so as to maximize image quality within that area. DCCS also provides critical high-resolution images to a ground screening team, which analyzes the images to assess damage (if any); in so doing, DCCS enables the team to clear initially suspect areas more quickly than would otherwise be possible and further saves time by minimizing the probability of re-imaging of areas already inspected. On the basis of experience with a previous version (2.0) of the software, the present version (3.0) incorporates a number of advanced imaging features that optimize crewmember capability and efficiency.

  10. Process simulation in digital camera system

    NASA Astrophysics Data System (ADS)

    Toadere, Florin

    2012-06-01

    The goal of this paper is to simulate the functionality of a digital camera system. The simulations cover the conversion from light to numerical signal and the color processing and rendering. We consider the image acquisition system to be linear shift invariant and axial. The light propagation is orthogonal to the system. We use a spectral image processing algorithm in order to simulate the radiometric properties of a digital camera. In the algorithm we take into consideration the transmittances of the: light source, lenses, filters and the quantum efficiency of a CMOS (complementary metal oxide semiconductor) sensor. The optical part is characterized by a multiple convolution between the different points spread functions of the optical components. We use a Cooke triplet, the aperture, the light fall off and the optical part of the CMOS sensor. The electrical part consists of the: Bayer sampling, interpolation, signal to noise ratio, dynamic range, analog to digital conversion and JPG compression. We reconstruct the noisy blurred image by blending different light exposed images in order to reduce the photon shot noise, also we filter the fixed pattern noise and we sharpen the image. Then we have the color processing blocks: white balancing, color correction, gamma correction, and conversion from XYZ color space to RGB color space. For the reproduction of color we use an OLED (organic light emitting diode) monitor. The analysis can be useful to assist students and engineers in image quality evaluation and imaging system design. Many other configurations of blocks can be used in our analysis.

  11. Digital Sensor Technology

    SciTech Connect

    Ted Quinn; Jerry Mauck; Richard Bockhorst; Ken Thomas

    2013-07-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy, reliability, availability, and maintainability. This report demonstrates these benefits in direct comparisons of digital and analog sensor applications. It also addresses the qualification issues that must be addressed in the application of digital sensor technology.

  12. Replacing 16-mm film cameras with high-definition digital cameras

    NASA Astrophysics Data System (ADS)

    Balch, Kris S.

    1995-09-01

    For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne gun cameras, 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, 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 camera from Kodak that has been designed to replace 16 mm high speed film cameras.

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

    PubMed Central

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

    2014-01-01

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

  14. Measurement of solar extinction in tower plants with digital cameras

    NASA Astrophysics Data System (ADS)

    Ballestrín, J.; Monterreal, R.; Carra, M. E.; Fernandez-Reche, J.; Barbero, J.; Marzo, A.

    2016-05-01

    Atmospheric extinction of solar radiation between the heliostat field and the receiver is accepted as a non-negligible source of energy loss in the increasingly large central receiver plants. However, the reality is that there is currently no reliable measurement method for this quantity and at present these plants are designed, built and operated without knowing this local parameter. Nowadays digital cameras are used in many scientific applications for their ability to convert available light into digital images. Its broad spectral range, high resolution and high signal to noise ratio, make them an interesting device in solar technology. In this work a method for atmospheric extinction measurement based on digital images is presented. The possibility of defining a measurement setup in circumstances similar to those of a tower plant increases the credibility of the method. This procedure is currently being implemented at Plataforma Solar de Almería.

  15. Practical target location and accuracy indicator in digital close range photogrammetry using consumer grade cameras

    NASA Astrophysics Data System (ADS)

    Moriya, Gentaro; Chikatsu, Hirofumi

    2011-07-01

    Recently, pixel numbers and functions of consumer grade digital camera are amazingly increasing by modern semiconductor and digital technology, and there are many low-priced consumer grade digital cameras which have more than 10 mega pixels on the market in Japan. In these circumstances, digital photogrammetry using consumer grade cameras is enormously expected in various application fields. There is a large body of literature on calibration of consumer grade digital cameras and circular target location. Target location with subpixel accuracy had been investigated as a star tracker issue, and many target location algorithms have been carried out. It is widely accepted that the least squares models with ellipse fitting is the most accurate algorithm. However, there are still problems for efficient digital close range photogrammetry. These problems are reconfirmation of the target location algorithms with subpixel accuracy for consumer grade digital cameras, relationship between number of edge points along target boundary and accuracy, and an indicator for estimating the accuracy of normal digital close range photogrammetry using consumer grade cameras. With this motive, an empirical testing of several algorithms for target location with subpixel accuracy and an indicator for estimating the accuracy are investigated in this paper using real data which were acquired indoors using 7 consumer grade digital cameras which have 7.2 mega pixels to 14.7 mega pixels.

  16. It's a Snap! Selecting the Right Digital Camera

    ERIC Educational Resources Information Center

    Browne, Ron

    2005-01-01

    Digital cameras can be wonderful teaching/learning tools in the preschool classroom. They can record and document student development, make text-free cues for pre-reading children, and develop learning prompts for discussion. In this article, the author discusses tips on selecting the right digital camera. Above all, it is important to consider…

  17. Methods for identification of images acquired with digital cameras

    NASA Astrophysics Data System (ADS)

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

    2001-02-01

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

  18. Digital dental photography. Part 4: choosing a camera.

    PubMed

    Ahmad, I

    2009-06-13

    With so many cameras and systems on the market, making a choice of the right one for your practice needs is a daunting task. As described in Part 1 of this series, a digital single reflex (DSLR) camera is an ideal choice for dental use in enabling the taking of portraits, close-up or macro images of the dentition and study casts. However, for the sake of completion, some other cameras systems that are used in dentistry are also discussed. PMID:19521372

  19. A Simple Spectrophotometer Using Common Materials and a Digital Camera

    ERIC Educational Resources Information Center

    Widiatmoko, Eko; Widayani; Budiman, Maman; Abdullah, Mikrajuddin; Khairurrijal

    2011-01-01

    A simple spectrophotometer was designed using cardboard, a DVD, a pocket digital camera, a tripod and a computer. The DVD was used as a diffraction grating and the camera as a light sensor. The spectrophotometer was calibrated using a reference light prior to use. The spectrophotometer was capable of measuring optical wavelengths with a…

  20. Digital cameras with designs inspired by the arthropod eye.

    PubMed

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

    2013-05-01

    In arthropods, evolution has created a remarkably sophisticated class of imaging systems, with a wide-angle field of view, low aberrations, high acuity to motion and an infinite depth of field. A challenge in building digital cameras with the hemispherical, compound apposition layouts of arthropod eyes is that essential design requirements cannot be met with existing planar sensor technologies or conventional optics. Here we present materials, mechanics and integration schemes that afford scalable pathways to working, arthropod-inspired cameras with nearly full hemispherical shapes (about 160 degrees). Their surfaces are densely populated by imaging elements (artificial ommatidia), which are comparable in number (180) to those of the eyes of fire ants (Solenopsis fugax) and bark beetles (Hylastes nigrinus). The devices combine elastomeric compound optical elements with deformable arrays of thin silicon photodetectors into integrated sheets that can be elastically transformed from the planar geometries in which they are fabricated to hemispherical shapes for integration into apposition cameras. Our imaging results and quantitative ray-tracing-based simulations illustrate key features of operation. These general strategies seem to be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes). PMID:23636401

  1. Characterizing Digital Camera Systems: A Prelude to Data Standards

    NASA Technical Reports Server (NTRS)

    Ryan, Robert

    2002-01-01

    This viewgraph presentation profiles: 1) Digital imaging systems; 2) Specifying a digital imagery product; and 3) Characterization of data acquisition systems. Advanced large array digital imaging systems are routinely being used. Digital imagery guidelines are being developed by ASPRS and ISPRS. Guidelines and standards are of little use without standardized characterization methods. Characterization of digital camera systems is important for supporting digital imagery guidelines. Specifications are characterized in the lab and/or the field. Laboratory characterization is critical for optimizing and defining performance. In-flight characterization is necessary for an end-to-end system test.

  2. Digital Sensor Technology

    SciTech Connect

    Thomas, Ken D.; Quinn, Edward L.; Mauck, Jerry L.; Bockhorst, Richard M.

    2015-02-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy and reliability. This paper, which refers to a final report issued in 2013, demonstrates these benefits in direct comparisons of digital and analog sensor applications. Improved accuracy results from the superior operating characteristics of digital sensors. These include improvements in sensor accuracy and drift and other related parameters which reduce total loop uncertainty and thereby increase safety and operating margins. An example instrument loop uncertainty calculation for a pressure sensor application is presented to illustrate these improvements. This is a side-by-side comparison of the instrument loop uncertainty for both an analog and a digital sensor in the same pressure measurement application. Similarly, improved sensor reliability is illustrated with a sample calculation for determining the probability of failure on demand, an industry standard reliability measure. This looks at equivalent analog and digital temperature sensors to draw the comparison. The results confirm substantial reliability improvement with the digital sensor, due in large part to ability to continuously monitor the health of a digital sensor such that problems can be immediately identified and corrected. This greatly reduces the likelihood of a latent failure condition of the sensor at the time of a design basis event. Notwithstanding the benefits of digital sensors, there are certain qualification issues that are inherent with digital technology and these are described in the report. One major qualification impediment for digital sensor implementation is software common cause failure (SCCF).

  3. PENTAX 645D Medium-Format Digital SLR Camera

    NASA Astrophysics Data System (ADS)

    Maekawa, Yasuyuki

    PENTAX 645D has been developped with the aim to offer a relatively affordable, yet highly operable and durable Digital SLR camera equipped with larger sensor, to nonprofessional, yet highly-enthusiastic photographers, whereas precedent cameras with similar format had been a tool of a professional photographer, both in terms of its extraordinary pricing and the extent of knowledge required for the handling of it. The focus of this article is to detail the unique feature of the Medium-Format Digital SLR camera, a product composed of the latest functionality and thought-out user interface developed in the eingeneering of standard APS-C Digital SLR, as well as the extensive knowledge of larger format cameras accumulated through the development of the film Medium-Format SLR.

  4. Digital Actuator Technology

    SciTech Connect

    Ken Thomas; Ted Quinn; Jerry Mauck; Richard Bockhorst

    2014-09-01

    There are significant developments underway in new types of actuators for power plant active components. Many of these make use of digital technology to provide a wide array of benefits in performance of the actuators and in reduced burden to maintain them. These new product offerings have gained considerable acceptance in use in process plants. In addition, they have been used in conventional power generation very successfully. This technology has been proven to deliver the benefits promised and substantiate the claims of improved performance. The nuclear industry has been reluctant to incorporate digital actuator technology into nuclear plant designs due to concerns due to a number of concerns. These could be summarized as cost, regulatory uncertainty, and a certain comfort factor with legacy analog technology. The replacement opportunity for these types of components represents a decision point for whether to invest in more modern technology that would provide superior operational and maintenance benefits. Yet, the application of digital technology has been problematic for the nuclear industry, due to qualification and regulatory issues. With some notable exceptions, the result has been a continuing reluctance to undertake the risks and uncertainties of implementing digital actuator technology when replacement opportunities present themselves. Rather, utilities would typically prefer to accept the performance limitations of the legacy analog actuator technologies to avoid impacts to project costs and schedules. The purpose of this report is to demonstrate that the benefits of digital actuator technology can be significant in terms of plant performance and that it is worthwhile to address the barriers currently holding back the widespread development and use of this technology. It addresses two important objectives in pursuit of the beneficial use of digital actuator technology for nuclear power plants: 1. To demonstrate the benefits of digital actuator

  5. CMOS Imaging Sensor Technology for Aerial Mapping Cameras

    NASA Astrophysics Data System (ADS)

    Neumann, Klaus; Welzenbach, Martin; Timm, Martin

    2016-06-01

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

  6. Improvement on the polynomial modeling of digital camera colorimetric characterization

    NASA Astrophysics Data System (ADS)

    Huang, Xiaoqiao; Yu, Hongfei; Shi, Junsheng; Tai, Yonghang

    2014-11-01

    The digital camera has become a requisite for people's life, also essential in imaging applications, and it is important to get more accurate colors with digital camera. The colorimetric characterization of digital camera is the basis of image copy and color management process. One of the traditional methods for deriving a colorimetric mapping between camera RGB signals and the tristimulus values CIEXYZ is to use polynomial modeling with 3×11 polynomial transfer matrices. In this paper, an improved polynomial modeling is presented, in which the normalized luminance replaces the camera inherent RGB values in the traditional polynomial modeling. The improved modeling can be described by a two stage model. The first stage, relationship between the camera RGB values and normalized luminance with six gray patches in the X-rite ColorChecker 24-color card was described as "Gamma", camera RGB values were converted into normalized luminance using Gamma. The second stage, the traditional polynomial modeling was improved to the colorimetric mapping between normalized luminance and the CIEXYZ. Meanwhile, this method was used under daylight lighting environment, the users can not measure the CIEXYZ of the color target char using professional instruments, but they can accomplish the task of the colorimetric characterization of digital camera. The experimental results show that: (1) the proposed method for the colorimetric characterization of digital camera performs better than traditional polynomial modeling; (2) it's a feasible approach to handle the color characteristics using this method under daylight environment without professional instruments, the result can satisfy for request of simple application.

  7. A simple spectrophotometer using common materials and a digital camera

    NASA Astrophysics Data System (ADS)

    Widiatmoko, Eko; Widayani; Budiman, Maman; Abdullah, Mikrajuddin; Khairurrijal

    2011-05-01

    A simple spectrophotometer was designed using cardboard, a DVD, a pocket digital camera, a tripod and a computer. The DVD was used as a diffraction grating and the camera as a light sensor. The spectrophotometer was calibrated using a reference light prior to use. The spectrophotometer was capable of measuring optical wavelengths with a theoretical accuracy as high as 0.2 nm. Using this spectrophotometer, wavelengths are determined via image processing.

  8. Automated 3D measurement with the DCS200 digital camera

    NASA Astrophysics Data System (ADS)

    Van den Heuvel, Frank A.

    1994-03-01

    A digital photogrammetric system for automated 3D coordinate measurement in a production environment has been developed. For the image acquisition the Kodak DCS200 digital camera is used. This camera is based on a standard 35-mm camera. The results of the radiometric and geometric calibration of the DCS200 camera show the potential of this camera for photogrammetric applications. The software part of the system performs the detection, identification, and measurement of artificial targets present in digital images. These artificial targets are designed for automatic detection in images of a complex scene. For the identification of the targets a circular bar code is read by the image processing software. The least squares template matching method is implemented for the target image measurement. A precision better than 2% of a pixel was obtained for the target location. The 3D coordinate computation is performed by Geodelta's bundle adjustment package BINAER. It includes extensive statistical testing to assess the accuracy of the results. Tests with the DCS200 camera show a repeatability of 18 micrometer standard deviation on a test field 60 X 50 X 30 centimeter. The achieved precision is in the order of 2 (DOT) 10-5.

  9. Review of up-to date digital cameras interfaces

    NASA Astrophysics Data System (ADS)

    Linkemann, Joachim

    2013-04-01

    Over the past 15 years, various interfaces on digital industrial cameras have been available on the market. This tutorial will give an overview of interfaces such as LVDS (RS644), Channel Link and Camera Link. In addition, other interfaces such as FireWire, Gigabit Ethernet, and now USB 3.0 have become more popular. Owing to their ease of use, these interfaces cover most of the market. Nevertheless, for certain applications and especially for higher bandwidths, Camera Link and CoaXPress are very useful. This tutorial will give a description of the advantages and disadvantages, comment on bandwidths, and provide recommendations on when to use which interface.

  10. Compression of CCD raw images for digital still cameras

    NASA Astrophysics Data System (ADS)

    Sriram, Parthasarathy; Sudharsanan, Subramania

    2005-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

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

  12. Bringing the Digital Camera to the Physics Lab

    ERIC Educational Resources Information Center

    Rossi, M.; Gratton, L. M.; Oss, S.

    2013-01-01

    We discuss how compressed images created by modern digital cameras can lead to even severe problems in the quantitative analysis of experiments based on such images. Difficulties result from the nonlinear treatment of lighting intensity values stored in compressed files. To overcome such troubles, one has to adopt noncompressed, native formats, as…

  13. Using a Digital Video Camera to Study Motion

    ERIC Educational Resources Information Center

    Abisdris, Gil; Phaneuf, Alain

    2007-01-01

    To illustrate how a digital video camera can be used to analyze various types of motion, this simple activity analyzes the motion and measures the acceleration due to gravity of a basketball in free fall. Although many excellent commercially available data loggers and software can accomplish this task, this activity requires almost no financial…

  14. Small Orbital Stereo Tracking Camera Technology Development

    NASA Technical Reports Server (NTRS)

    Bryan, Tom; MacLeod, Todd; Gagliano, Larry

    2016-01-01

    On-Orbit Small Debris Tracking and Characterization is a technical gap in the current National Space Situational Awareness necessary to safeguard orbital assets and crew. This poses a major risk of MOD damage to ISS and Exploration vehicles. In 2015 this technology was added to NASA's Office of Chief Technologist roadmap. For missions flying in or assembled in or staging from LEO, the physical threat to vehicle and crew is needed in order to properly design the proper level of MOD impact shielding and proper mission design restrictions. Need to verify debris flux and size population versus ground RADAR tracking. Use of ISS for In-Situ Orbital Debris Tracking development provides attitude, power, data and orbital access without a dedicated spacecraft or restricted operations on-board a host vehicle as a secondary payload. Sensor Applicable to in-situ measuring orbital debris in flux and population in other orbits or on other vehicles. Could enhance safety on and around ISS. Some technologies extensible to monitoring of extraterrestrial debris as well To help accomplish this, new technologies must be developed quickly. The Small Orbital Stereo Tracking Camera is one such up and coming technology. It consists of flying a pair of intensified megapixel telephoto cameras to evaluate Orbital Debris (OD) monitoring in proximity of International Space Station. It will demonstrate on-orbit optical tracking (in situ) of various sized objects versus ground RADAR tracking and small OD models. The cameras are based on Flight Proven Advanced Video Guidance Sensor pixel to spot algorithms (Orbital Express) and military targeting cameras. And by using twin cameras we can provide Stereo images for ranging & mission redundancy. When pointed into the orbital velocity vector (RAM), objects approaching or near the stereo camera set can be differentiated from the stars moving upward in background.

  15. Small Orbital Stereo Tracking Camera Technology Development

    NASA Astrophysics Data System (ADS)

    Gagliano, L.; Bryan, T.; MacLeod, T.

    On-Orbit Small Debris Tracking and Characterization is a technical gap in the current National Space Situational Awareness necessary to safeguard orbital assets and crew. This poses a major risk of MOD damage to ISS and Exploration vehicles. In 2015 this technology was added to NASAs Office of Chief Technologist roadmap. For missions flying in or assembled in or staging from LEO, the physical threat to vehicle and crew is needed in order to properly design the proper level of MOD impact shielding and proper mission design restrictions. Need to verify debris flux and size population versus ground RADAR tracking. Use of ISS for In-Situ Orbital Debris Tracking development provides attitude, power, data and orbital access without a dedicated spacecraft or restricted operations on-board a host vehicle as a secondary payload. Sensor Applicable to in-situ measuring orbital debris in flux and population in other orbits or on other vehicles. Could enhance safety on and around ISS. Some technologies extensible to monitoring of extraterrestrial debris as well To help accomplish this, new technologies must be developed quickly. The Small Orbital Stereo Tracking Camera is one such up and coming technology. It consists of flying a pair of intensified megapixel telephoto cameras to evaluate Orbital Debris (OD) monitoring in proximity of International Space Station. It will demonstrate on-orbit optical tracking (in situ) of various sized objects versus ground RADAR tracking and small OD models. The cameras are based on Flight Proven Advanced Video Guidance Sensor pixel to spot algorithms (Orbital Express) and military targeting cameras. And by using twin cameras we can provide Stereo images for ranging & mission redundancy. When pointed into the orbital velocity vector (RAM), objects approaching or near the stereo camera set can be differentiated from the stars moving upward in background.

  16. Small Orbital Stereo Tracking Camera Technology Development

    NASA Technical Reports Server (NTRS)

    Bryan, Tom; Macleod, Todd; Gagliano, Larry

    2015-01-01

    On-Orbit Small Debris Tracking and Characterization is a technical gap in the current National Space Situational Awareness necessary to safeguard orbital assets and crew. This poses a major risk of MOD damage to ISS and Exploration vehicles. In 2015 this technology was added to NASA's Office of Chief Technologist roadmap. For missions flying in or assembled in or staging from LEO, the physical threat to vehicle and crew is needed in order to properly design the proper level of MOD impact shielding and proper mission design restrictions. Need to verify debris flux and size population versus ground RADAR tracking. Use of ISS for In-Situ Orbital Debris Tracking development provides attitude, power, data and orbital access without a dedicated spacecraft or restricted operations on-board a host vehicle as a secondary payload. Sensor Applicable to in-situ measuring orbital debris in flux and population in other orbits or on other vehicles. Could enhance safety on and around ISS. Some technologies extensible to monitoring of extraterrestrial debris as well to help accomplish this, new technologies must be developed quickly. The Small Orbital Stereo Tracking Camera is one such up and coming technology. It consists of flying a pair of intensified megapixel telephoto cameras to evaluate Orbital Debris (OD) monitoring in proximity of International Space Station. It will demonstrate on-orbit optical tracking (in situ) of various sized objects versus ground RADAR tracking and small OD models. The cameras are based on Flight Proven Advanced Video Guidance Sensor pixel to spot algorithms (Orbital Express) and military targeting cameras. And by using twin cameras we can provide Stereo images for ranging & mission redundancy. When pointed into the orbital velocity vector (RAM), objects approaching or near the stereo camera set can be differentiated from the stars moving upward in background.

  17. Digital Optical Circuit Technology

    NASA Technical Reports Server (NTRS)

    Dove, B. L. (Editor)

    1985-01-01

    The Proceedings for the 48th Meeting of the AGARD Avionics Panel contain the 18 papers presented a Technical Evaluation Report, and discussions that followed the presentations of papers. Seven papers were presented in the session devoted to optical bistability. Optical logic was addressed by three papers. The session on sources, modulators and demodulators presented three papers. Five papers were given in the final session on all optical systems. The purpose of this Specialists' Meeting was to present the research and development status of digital optical circuit technology and to examine its relevance in the broad context of digital processing, communication, radar, avionics and flight control systems implementation.

  18. Utilization of consumer level digital cameras in astronomy

    NASA Astrophysics Data System (ADS)

    Páta, Petr; Fliegel, Karel; Klíma, Miloš; Blažek, Martin; Řeřábek, Martin

    2010-08-01

    This paper presents a study of possible utilization of digital single-lens reflex (DSLR) cameras in astronomy. The DSLRs have a great advantage over the professional equipments in better cost efficiency with comparable usability for selected purposes. The quality of electro-optical system in the DSLR camera determines the area where it can be used with acceptable precision. At first a set of important camera parameters for astronomical utilization is introduced in the paper. Color filter array (CFA) structure, demosaicing algorithm, image sensor spectral properties, noise and transfer characteristics are the parameters that belong among the very important ones and these are further analyzed in the paper. Compression of astronomical images using the KLT approach is also described below. The potential impact of these parameters on position and photometric measurement is presented based on the analysis and measurements with the wide-angle lens. The prospective utilization of consumer DSLR camera as a substitute for expensive devices is discussed.

  19. Use of the Digital Camera To Increase Student Interest and Learning in High School Biology.

    ERIC Educational Resources Information Center

    Tatar, Denise; Robinson, Mike

    2003-01-01

    Attempts to answer two research questions: (1) Does the use of a digital camera in laboratory activities increase student learning?; and (2) Does the use of digital cameras motivate students to take a greater interest in laboratory work? Results indicate that the digital camera did increase student learning of process skills in two biology…

  20. Observation of Planetary Motion Using a Digital Camera

    ERIC Educational Resources Information Center

    Meyn, Jan-Peter

    2008-01-01

    A digital SLR camera with a standard lens (50 mm focal length, f/1.4) on a fixed tripod is used to obtain photographs of the sky which contain stars up to 8[superscript m] apparent magnitude. The angle of view is large enough to ensure visual identification of the photograph with a large sky region in a stellar map. The resolution is sufficient to…

  1. Digital camera system built on JPEG2000 compression and decompression

    NASA Astrophysics Data System (ADS)

    Atsumi, Eiji

    2003-05-01

    Processing architecture for digital camera has been built on JPEG2000 compression system. Concerns are to minimize processing power and data traffic inside (data-bandwidth at interface) and out-side (compression efficiency) of camera system. Key idea is to decompose Bayer matrix data given from image sensor into four half-resolution planes instead of interpolating to three full-resolution planes. With a new compression standard, JPEG2000, capable of handling multi-component image, the four-plane representation can be encoded into a single bit-stream. The representation saves data traffic between image reconstruction stage and compression stage by 1/3 to 1/2 compared to the Bayer-interpolated data. Not only reduced processing power prior to and during compression but also competitive or superior compression efficiency is achieved. On reconstruction to full resolution is Bayer-interpolation and/or edge-enhancement required as a post-processing to a standard decoder, while half or smaller resolution image is reconstructed without a post-processing. For mobile terminals with an integrated camera (image reconstruction in camera h/w and compression in terminal processor), this scheme helps to accommodate increased resolution with all the limited data-bandwidth from camera to terminal processor and limited processing capability.

  2. Database Technology in Digital Libraries.

    ERIC Educational Resources Information Center

    Preston, Carole; Lin, Binshan

    2002-01-01

    Reviews issues relating to database technology and digital libraries. Highlights include resource sharing; ongoing digital library projects; metadata; user interfaces; query processing; interoperability; data quality; copyright infringement; and managerial implications, including electronic versus printed materials, accessibility,…

  3. Improvement of digital photoelasticity based on camera response function.

    PubMed

    Chang, Shih-Hsin; Wu, Hsien-Huang P

    2011-09-20

    Studies on photoelasticity have been conducted by many researchers in recent years, and many equations for photoelastic analysis based on digital images were proposed. While these equations were all presented by the light intensity emitted from the analyzer, pixel values of the digital image were actually used in the real calculations. In this paper, a proposal of using relative light intensity obtained by the camera response function to replace the pixel value for photoelastic analysis was investigated. Generation of isochromatic images based on relative light intensity and pixel value were compared to evaluate the effectiveness of the new approach. The results showed that when relative light intensity was used, the quality of an isochromatic image can be greatly improved both visually and quantitatively. We believe that the technique proposed in this paper can also be used to improve the performance for the other types of photoelastic analysis using digital images. PMID:21947044

  4. Night sky photometry with amateur-grade digital cameras

    NASA Astrophysics Data System (ADS)

    Mrozek, Tomasz; Gronkiewicz, Dominik; Kolomanski, Sylwester; Steslicki, Marek

    2015-08-01

    Measurements of night sky brightness can give us valuable information on light pollution. The more the measurements we have the better is our knowledge on the spatial distribution of the pollution on local and global scale.High accuracy professional photometry of night sky can be performed with dedicated instruments. The main drawbacks of this method are high price and low mobility. This limits an amount of observers and therefore amount of photometric data that can be collected. In order to overcome the problem of limited amount of data we can involve amateur astronomers in photometry of night sky. However, to achieve this goal we need a method that utilizes equipment which is usually used by amateur astronomers, e.g digital cameras.We propose a method that enables good accuracy photometry of night sky with a use of digital compact or DSLR cameras. In the method reduction of observations and standarization to Johnson UBV system are performed. We tested several cameras and compared results to Sky Quality Meter (SQM) measurements. The overall consistency for results is within 0.2 mag.

  5. Establishing imaging sensor specifications for digital still cameras

    NASA Astrophysics Data System (ADS)

    Kriss, Michael A.

    2007-02-01

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

  6. A large distributed digital camera system for accelerator beam diagnostics

    NASA Astrophysics Data System (ADS)

    Catani, L.; Cianchi, A.; Di Pirro, G.; Honkavaara, K.

    2005-07-01

    Optical diagnostics, providing images of accelerated particle beams using radiation emitted by particles impinging a radiator, typically a fluorescent screen, has been extensively used, especially on electron linacs, since the 1970's. Higher intensity beams available in the last decade allow extending the use of beam imaging techniques to perform precise measurements of important beam parameters such as emittance, energy, and energy spread using optical transition radiation (OTR). OTR-based diagnostics systems are extensively used on the superconducting TESLA Test Facility (TTF) linac driving the vacuum ultraviolet free electron laser (VUV-FEL) at the Deutsches Elektronen-Synchrotron facility. Up to 30 optical diagnostic stations have been installed at various positions along the 250-m-long linac, each equipped with a high-performance digital camera. This paper describes the new approach to the design of the hardware and software setups required by the complex topology of such a distributed camera system.

  7. Preparation of a Low-Cost Digital Camera System for Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Off-the-shelf consumer digital cameras are convenient and user-friendly. However, the use of these cameras in remote sensing is limited because convenient methods for concurrently determining visible and near-infrared (NIR) radiation have not been developed. Two Nikon COOLPIX 4300 digital cameras ...

  8. Self-calibration of digital aerial camera using combined orthogonal models

    NASA Astrophysics Data System (ADS)

    Babapour, Hadi; Mokhtarzade, Mehdi; Valadan Zoej, Mohamad Javad

    2016-07-01

    The emergence of new digital aerial cameras and the diverse design and technology used in this type of cameras require in-situ calibration. Self-calibration methods, e.g. the Fourier model, are primarily used; however, additional parameters employed in such methods have not yet met the expectations to desirably model the complex multiple distortions existing in the digital aerial cameras. The present study proposes the Chebyshev-Fourier (CHF) and Jacobi-Fourier (JF) combined orthogonal models. The models are evaluated for the multiple distortions using both simulated and real data, the latter being derived from an UltraCam digital camera. The results indicate that the JF model is superior to the other methods where, e.g., in the UltraCam scenario, it improves the planimetric and vertical accuracy over the Fourier model by 18% and 22%, respectively. Furthermore, a 30% and 16% of reduction in external and internal correlation is obtained via this approach which is very promising.

  9. Fast measurement of temporal noise of digital camera's photosensors

    NASA Astrophysics Data System (ADS)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Rostislav S.; Starikov, Sergey N.

    2015-10-01

    Currently photo- and videocameras are widespread parts of both scientific experimental setups and consumer applications. They are used in optics, radiophysics, astrophotography, chemistry, and other various fields of science and technology such as control systems and video-surveillance monitoring. One of the main information limitations of photoand videocameras are noises of photosensor pixels. Camera's photosensor noise can be divided into random and pattern components. Temporal noise includes random noise component while spatial noise includes pattern noise component. Spatial part usually several times lower in magnitude than temporal. At first approximation spatial noises might be neglected. Earlier we proposed modification of the automatic segmentation of non-uniform targets (ASNT) method for measurement of temporal noise of photo- and videocameras. Only two frames are sufficient for noise measurement with the modified method. In result, proposed ASNT modification should allow fast and accurate measurement of temporal noise. In this paper, we estimated light and dark temporal noises of four cameras of different types using the modified ASNT method with only several frames. These cameras are: consumer photocamera Canon EOS 400D (CMOS, 10.1 MP, 12 bit ADC), scientific camera MegaPlus II ES11000 (CCD, 10.7 MP, 12 bit ADC), industrial camera PixeLink PLB781F (CMOS, 6.6 MP, 10 bit ADC) and video-surveillance camera Watec LCL-902C (CCD, 0.47 MP, external 8 bit ADC). Experimental dependencies of temporal noise on signal value are in good agreement with fitted curves based on a Poisson distribution excluding areas near saturation. We measured elapsed time for processing of shots used for temporal noise estimation. The results demonstrate the possibility of fast obtaining of dependency of camera full temporal noise on signal value with the proposed ASNT modification.

  10. Investigating thin film interference with a digital camera

    NASA Astrophysics Data System (ADS)

    Atkins, Leslie J.; Elliott, Richard C.

    2010-12-01

    Thin film interference is discussed in most introductory physics courses as an intriguing example of wave interference. Although students may understand the interference mechanism that determines the colors of a film, they are likely to have difficulty understanding why soap bubbles and oil slicks have a distinctive set of colors—colors that are strikingly different from those present in the rainbow. This article describes a way to model these colors and a simple method for investigating them using a digital camera and a computer.

  11. Social Justice through Literacy: Integrating Digital Video Cameras in Reading Summaries and Responses

    ERIC Educational Resources Information Center

    Liu, Rong; Unger, John A.; Scullion, Vicki A.

    2014-01-01

    Drawing data from an action-oriented research project for integrating digital video cameras into the reading process in pre-college courses, this study proposes using digital video cameras in reading summaries and responses to promote critical thinking and to teach social justice concepts. The digital video research project is founded on…

  12. Off-axis digital holographic camera for quantitative phase microscopy

    PubMed Central

    Monemhaghdoust, Zahra; Montfort, Frédéric; Emery, Yves; Depeursinge, Christian; Moser, Christophe

    2014-01-01

    We propose and experimentally demonstrate a digital holographic camera which can be attached to the camera port of a conventional microscope for obtaining digital holograms in a self-reference configuration, under short coherence illumination and in a single shot. A thick holographic grating filters the beam containing the sample information in two dimensions through diffraction. The filtered beam creates the reference arm of the interferometer. The spatial filtering method, based on the high angular selectivity of the thick grating, reduces the alignment sensitivity to angular displacements compared with pinhole based Fourier filtering. The addition of a thin holographic grating alters the coherence plane tilt introduced by the thick grating so as to create high-visibility interference over the entire field of view. The acquired full-field off-axis holograms are processed to retrieve the amplitude and phase information of the sample. The system produces phase images of cheek cells qualitatively similar to phase images extracted with a standard commercial DHM. PMID:24940535

  13. Lytro camera technology: theory, algorithms, performance analysis

    NASA Astrophysics Data System (ADS)

    Georgiev, Todor; Yu, Zhan; Lumsdaine, Andrew; Goma, Sergio

    2013-03-01

    The Lytro camera is the first implementation of a plenoptic camera for the consumer market. We consider it a successful example of the miniaturization aided by the increase in computational power characterizing mobile computational photography. The plenoptic camera approach to radiance capture uses a microlens array as an imaging system focused on the focal plane of the main camera lens. This paper analyzes the performance of Lytro camera from a system level perspective, considering the Lytro camera as a black box, and uses our interpretation of Lytro image data saved by the camera. We present our findings based on our interpretation of Lytro camera file structure, image calibration and image rendering; in this context, artifacts and final image resolution are discussed.

  14. Digital camera calibration for color measurements on prints

    NASA Astrophysics Data System (ADS)

    Andersson, Mattias

    2007-01-01

    Flatbed scanners and digital cameras have become established and widely used color imaging devices. If colorimetrically calibrated, these trichromatic devices can provide fast color measurement tools in applications such as printer calibration, process control, objective print quality measurements and color management. However, in calibrations intended to be used for color measurements on printed matter, the media dependency must be considered. Very good results can be achieved when the calibration is carried out on a single media and then applied for measurements on the same media, or at least a media of a very similar type. Significantly poorer results can be observed when the calibration is carried out for one printer-substrate combination and then applied for measurements on targets produced with another printer-substrate combination. Even if the problem is restricted to the color calibration of a scanner or camera for different paper media printed on a single printer, it is still tedious work to make a separate calibration for each new paper grade to be used in the printer. Therefore, it would be of interest to find a method where it is sufficient to characterize for only one or a few papers within a grade segment and then be able to apply a correction based on measurable optical paper properties. However, before being able to make any corrections, the influence of measurable paper properties on color characterizations must be studied and modeled. Fluorescence has been mentioned1-3 as a potential source of error in color calibrations for measurements on printed matter. In order to improve paper whiteness, producers of printing paper add bluish dye and fluorescent whitening agents (FWA) to the paper4. In this study, the influence of FWA in printing paper on the color calibration of a digital camera for color measurements on printed targets is discussed. To study the effect of FWA in the paper, a set of papers with varying additions of FWA but otherwise

  15. Digital Intelligence Fostered by Technology

    ERIC Educational Resources Information Center

    Adams, Nan B.

    2004-01-01

    Through interaction with digital technologies for work, play, and communication, the pattern for intellectual development is being altered. The multiple intelligences theoretical framework developed by Gardner (1983) is easily employed to provide evidence that yet another intelligence, digital intelligence, has emerged. In a postmodern pluralistic…

  16. Art Education Technology: Digital Storytelling

    ERIC Educational Resources Information Center

    Chung, Sheng Kuan

    2007-01-01

    The application of digital storytelling to art education is an interdisciplinary, inquiry-based, hands-on project that integrates the arts, education, local communities, technology, and storytelling. Through digital storytelling, students develop and apply multiliteracy skills, aesthetic sensitivities, and critical faculties to address greater…

  17. Encrypting Digital Camera with Automatic Encryption Key Deletion

    NASA Technical Reports Server (NTRS)

    Oakley, Ernest C. (Inventor)

    2007-01-01

    A digital video camera includes an image sensor capable of producing a frame of video data representing an image viewed by the sensor, an image memory for storing video data such as previously recorded frame data in a video frame location of the image memory, a read circuit for fetching the previously recorded frame data, an encryption circuit having an encryption key input connected to receive the previously recorded frame data from the read circuit as an encryption key, an un-encrypted data input connected to receive the frame of video data from the image sensor and an encrypted data output port, and a write circuit for writing a frame of encrypted video data received from the encrypted data output port of the encryption circuit to the memory and overwriting the video frame location storing the previously recorded frame data.

  18. Verification of Potency of Aerial Digital Oblique Cameras for Aerial Photogrammetry in Japan

    NASA Astrophysics Data System (ADS)

    Nakada, Ryuji; Takigawa, Masanori; Ohga, Tomowo; Fujii, Noritsuna

    2016-06-01

    Digital oblique aerial camera (hereinafter called "oblique cameras") is an assembly of medium format digital cameras capable of shooting digital aerial photographs in five directions i.e. nadir view and oblique views (forward and backward, left and right views) simultaneously and it is used for shooting digital aerial photographs efficiently for generating 3D models in a wide area. For aerial photogrammetry of public survey in Japan, it is required to use large format cameras, like DMC and UltraCam series, to ensure aerial photogrammetric accuracy. Although oblique cameras are intended to generate 3D models, digital aerial photographs in 5 directions taken with them should not be limited to 3D model production but they may also be allowed for digital mapping and photomaps of required public survey accuracy in Japan. In order to verify the potency of using oblique cameras for aerial photogrammetry (simultaneous adjustment, digital mapping and photomaps), (1) a viewer was developed to interpret digital aerial photographs taken with oblique cameras, (2) digital aerial photographs were shot with an oblique camera owned by us, a Penta DigiCAM of IGI mbH, and (3) accuracy of 3D measurements was verified.

  19. Digital EO camera system VOS 40/270 for tactical reconnaissance pos RecceLite

    NASA Astrophysics Data System (ADS)

    Uhl, Bernd

    2002-11-01

    This paper describes the design concept and the technical features of a new developed EO camera. The camera is integrated on a stabilized sensor platform of a tactical reconnaissance pod for extended pointing capability and wide field ground coverage.One of the major design constraints was the extremely small space available in the front gimbals, shared with a high resolution IR FPA Sensor in the other half of the gimbals. The line-of-sight of both sensors is harmonized, leading to multi-spectral information of the same ground target. The sensor features a high resolution zoom lens, large FPA detector, automatic focus and exposure control. An unique feature of the camera is automatic mass compensation when the zoom lens elements change their position during FOV change to keep the balancing of the sensors on the gimbal. The VOS 40/270 camera represents a new generation of tactical reconnaissance sensors for stabilized platform integration. The design of the VOS 40/270 camera system employs the latest emerging technologies in an all digital reconnaissance system.

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

    SciTech Connect

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

    2014-09-21

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

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

    DOE PAGESBeta

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

    2014-09-21

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

  2. Tape measuring system using linear encoder and digital camera

    NASA Astrophysics Data System (ADS)

    Eom, Tae Bong; Jeong, Don Young; Kim, Myung Soon; Kim, Jae Wan; Kim, Jong Ahn

    2013-04-01

    We have designed and constructed the calibration system of line standards such as tape and rule for the secondary calibration laboratories. The system consists of the main body with linear stage and linear encoder, the optical microscope with digital camera, and the computer. The base of the system is a aluminum profile with 2.9 m length, 0.09 m height and 0.18 m width. The linear stage and the linear encoder are fixed on the aluminum profile. The micro-stage driven by micrometer is fixed on the carriage of the long linear stage, and the optical microscope with digital camera and the tablet PC are on the this stage. The linear encoder counts the moving distance of the linear stage with resolution of 1 μm and its counting value is transferred to the tablet PC. The image of the scale mark of the tape is captured by the CCD camera of optical microscope and transferred to the PC through USB interface. The computer automatically determines the center of the scale mark by image processing technique and at the same time reads the moving distance of the linear stage. As a result, the computer can calculate the interval between the scale marks of the tape. In order to achieve the high accuracy, the linear encoder should be calibrated using the laser interferometer or the rigid steel rule. This calibration data of the linear encoder is stored at the computer and the computer corrects the reading value of the linear encoder. In order to determine the center of the scale mark, we use three different algorithms. First, the image profile over specified threshold level is fitted in even order polynomial and the axis of the polynomial is used as the center of the line. Second, the left side and right side areas at the center of the image profile are calculated so that two areas are same. Third, the left and right edges of the image profile are determined at every intensity level of the image and the center of the graduation is calculated as an average of the centers of the left

  3. Development of Digital SLR Camera: PENTAX K-7

    NASA Astrophysics Data System (ADS)

    Kawauchi, Hiraku

    The DSLR "PENTAX K-7" comes with an easy-to-carry, minimal yet functional small form factor, a long inherited identities of the PENTAX brand. Nevertheless for its compact body, this camera has up-to-date enhanced fundamental features such as high-quality viewfinder, enhanced shutter mechanism, extended continuous shooting capabilities, reliable exposure control, and fine-tuned AF systems, as well as strings of newest technologies such as movie recording capability and automatic leveling function. The main focus of this article is to reveal the ideas behind the concept making of this product and its distinguished features.

  4. Property of the Large Format Digital Aerial Camera Dmc II

    NASA Astrophysics Data System (ADS)

    Jacobsen, K.; Neumann, K.

    2012-07-01

    Z/I Imaging introduced with the DMC II 140, 230 and 250 digital aerial cameras with a very large format CCD for the panchromatic channel. The CCDs have with 140 / 230 / 250 mega pixel a size not available in photogrammetry before. CCDs in general have a very high relative accuracy, but the overall geometry has to be checked as well as the influence of not flat CCDs. A CCD with a size of 96mm × 82mm must have a flatness or knowledge of flatness in the range of 1μm if the camera accuracy in the range of 1.3μm shall not be influenced. The DMC II cameras have been evaluated with three different flying heights leading to 5cm, 9cm and 15cm or 20cm GSD, crossing flight lines and 60% side lap. The optimal test conditions guaranteed the precise determination of the object coordinates as well as the systematic image errors. All three camera types show only very small systematic image errors, ranging in the root mean square between 0.12μm up to 0.3μm with extreme values not exceeding 1.6μm. The remaining systematic image errors, determined by analysis of the image residuals and not covered by the additional parameters, are negligible. A standard deviation of the object point heights below the GSD, determined at independent check points, even in blocks with just 20% side lap and 60% end lap is standard. Corresponding to the excellent image geometry the object point coordinates are only slightly influenced by the self calibration. For all DMCII types the handling of image models for data acquisition must not be supported by an improvement of the image coordinates by the determined systematic image errors. Such an improvement up to now is not standard for photogrammetric software packages. The advantage of a single monolithic CCD is obvious. An edge analysis of pan-sharpened DMC II 250 images resulted in factors for the effective resolution below 1.0. The result below 1.0 is only possible by contrast enhancement, but this requires with low image noise, demonstrating the

  5. Use of a Digital Camera To Document Student Observations in a Microbiology Laboratory Class.

    ERIC Educational Resources Information Center

    Mills, David A.; Kelley, Kevin; Jones, Michael

    2001-01-01

    Points out the lack of microscopic images of wine-related microbes. Uses a digital camera during a wine microbiology laboratory to capture student-generated microscope images. Discusses the advantages of using a digital camera in a teaching lab. (YDS)

  6. Comparison of the effectiveness of three retinal camera technologies for malarial retinopathy detection in Malawi

    NASA Astrophysics Data System (ADS)

    Soliz, Peter; Nemeth, Sheila C.; Barriga, E. Simon; Harding, Simon P.; Lewallen, Susan; Taylor, Terrie E.; MacCormick, Ian J.; Joshi, Vinayak S.

    2016-03-01

    The purpose of this study was to test the suitability of three available camera technologies (desktop, portable, and iphone based) for imaging comatose children who presented with clinical symptoms of malaria. Ultimately, the results of the project would form the basis for a design of a future camera to screen for malaria retinopathy (MR) in a resource challenged environment. The desktop, portable, and i-phone based cameras were represented by the Topcon, Pictor Plus, and Peek cameras, respectively. These cameras were tested on N=23 children presenting with symptoms of cerebral malaria (CM) at a malaria clinic, Queen Elizabeth Teaching Hospital in Malawi, Africa. Each patient was dilated for binocular indirect ophthalmoscopy (BIO) exam by an ophthalmologist followed by imaging with all three cameras. Each of the cases was graded according to an internationally established protocol and compared to the BIO as the clinical ground truth. The reader used three principal retinal lesions as markers for MR: hemorrhages, retinal whitening, and vessel discoloration. The study found that the mid-priced Pictor Plus hand-held camera performed considerably better than the lower price mobile phone-based camera, and slightly the higher priced table top camera. When comparing the readings of digital images against the clinical reference standard (BIO), the Pictor Plus camera had sensitivity and specificity for MR of 100% and 87%, respectively. This compares to a sensitivity and specificity of 87% and 75% for the i-phone based camera and 100% and 75% for the desktop camera. The drawback of all the cameras were their limited field of view which did not allow complete view of the periphery where vessel discoloration occurs most frequently. The consequence was that vessel discoloration was not addressed in this study. None of the cameras offered real-time image quality assessment to ensure high quality images to afford the best possible opportunity for reading by a remotely located

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

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L. (Inventor)

    1996-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L. (Inventor)

    1993-01-01

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

  9. Development of High Speed Digital Camera: EXILIM EX-F1

    NASA Astrophysics Data System (ADS)

    Nojima, Osamu

    The EX-F1 is a high speed digital camera featuring a revolutionary improvement in burst shooting speed that is expected to create entirely new markets. This model incorporates a high speed CMOS sensor and a high speed LSI processor. With this model, CASIO has achieved an ultra-high speed 60 frames per second (fps) burst rate for still images, together with 1,200 fps high speed movie that captures movements which cannot even be seen by human eyes. Moreover, this model can record movies at full High-Definition. After launching it into the market, it was able to get a lot of high appraisals as an innovation camera. We will introduce the concept, features and technologies about the EX-F1.

  10. Passive auto-focus for digital still cameras and camera phones: Filter-switching and low-light techniques

    NASA Astrophysics Data System (ADS)

    Gamadia, Mark Noel

    In order to gain valuable market share in the growing consumer digital still camera and camera phone market, camera manufacturers have to continually add and improve existing features to their latest product offerings. Auto-focus (AF) is one such feature, whose aim is to enable consumers to quickly take sharply focused pictures with little or no manual intervention in adjusting the camera's focus lens. While AF has been a standard feature in digital still and cell-phone cameras, consumers often complain about their cameras' slow AF performance, which may lead to missed photographic opportunities, rendering valuable moments and events with undesired out-of-focus pictures. This dissertation addresses this critical issue to advance the state-of-the-art in the digital band-pass filter, passive AF method. This method is widely used to realize AF in the camera industry, where a focus actuator is adjusted via a search algorithm to locate the in-focus position by maximizing a sharpness measure extracted from a particular frequency band of the incoming image of the scene. There are no known systematic methods for automatically deriving the parameters such as the digital pass-bands or the search step-size increments used in existing passive AF schemes. Conventional methods require time consuming experimentation and tuning in order to arrive at a set of parameters which balance AF performance in terms of speed and accuracy ultimately causing a delay in product time-to-market. This dissertation presents a new framework for determining an optimal set of passive AF parameters, named Filter- Switching AF, providing an automatic approach to achieve superior AF performance, both in good and low lighting conditions based on the following performance measures (metrics): speed (total number of iterations), accuracy (offset from truth), power consumption (total distance moved), and user experience (in-focus position overrun). Performance results using three different prototype cameras

  11. High-end aerial digital cameras and their impact on the automation and quality of the production workflow

    NASA Astrophysics Data System (ADS)

    Paparoditis, Nicolas; Souchon, Jean-Philippe; Martinoty, Gilles; Pierrot-Deseilligny, Marc

    The IGN digital camera project was established in the early 1990s. The first research surveys were carried out in 1996 and the digital camera was first used in production in 2000. In 2004 approximately 10 French departments (accounting for 10% of the territory) were covered with a four-head camera system and since summer 2005 all IGN imagery has been acquired digitally. Nevertheless the camera system is still evolving, with tests on new geometric configurations being continuously undertaken. The progressive integration of the system in IGN production workflows has allowed IGN to keep the system evolving in accordance with production needs. Remaining problems are due to specific camera characteristics such as CCD format, the optical quality of off-the-shelf lenses, and because some production tools are ill-adapted to digital images with a large dynamic range. However, when considering the pros and cons of integrating these images into production lines, the disadvantages are largely balanced by the numerous benefits this technology offers.

  12. Aerosol retrieval from twilight photographs taken by a digital camera

    NASA Astrophysics Data System (ADS)

    Saito, M.; Iwabuchi, H.

    2014-12-01

    Twilight sky, one of the most beautiful sights seen in our daily life, varies day by day, because atmospheric components such as ozone and aerosols also varies day by day. Recent studies have revealed the effects of tropospheric aerosols on twilight sky. In this study, we develop a new algorithm for aerosol retrievals from twilight photographs taken by a digital single reflex-lens camera in solar zenith angle of 90-96˚ with interval of 1˚. A radiative transfer model taking spherical-shell atmosphere, multiple scattering and refraction into account is used as a forward model, and the optimal estimation is used as an inversion calculation to infer the aerosol optical and radiative properties. The sensitivity tests show that tropospheric (stratospheric) aerosol optical thickness is responsible to the distribution of twilight sky color and brightness near the horizon (in viewing angles of 10˚ to 20˚) and aerosol size distribution is responsible to the angular distribution of brightness near the solar direction. The AOTs are inferred with small uncertainties and agree very well with that from the Skyradiometer. In this conference, several case studies using the algorithm will be shown.

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

    NASA Astrophysics Data System (ADS)

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

    2005-02-01

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

  14. DR with a DSLR: Digital Radiography with a Digital Single-Lens Reflex camera

    PubMed Central

    Fan, Helen; Durko, Heather L.; Moore, Stephen K.; Moore, Jared; Miller, Brian W.; Furenlid, Lars R.; Pradhan, Sunil; Barrett, Harrison H.

    2010-01-01

    An inexpensive, portable digital radiography (DR) detector system for use in remote regions has been built and evaluated. The system utilizes a large-format digital single-lens reflex (DSLR) camera to capture the image from a standard fluorescent screen. The large sensor area allows relatively small demagnification factors and hence minimizes the light loss. The system has been used for initial phantom tests in urban hospitals and Himalayan clinics in Nepal, and it has been evaluated in the laboratory at the University of Arizona by additional phantom studies. Typical phantom images are presented in this paper, and a simplified discussion of the detective quantum efficiency of the detector is given. PMID:21516238

  15. Real-time object tracking for moving target auto-focus in digital camera

    NASA Astrophysics Data System (ADS)

    Guan, Haike; Niinami, Norikatsu; Liu, Tong

    2015-02-01

    Focusing at a moving object accurately is difficult and important to take photo of the target successfully in a digital camera. Because the object often moves randomly and changes its shape frequently, position and distance of the target should be estimated at real-time so as to focus at the objet precisely. We propose a new method of real-time object tracking to do auto-focus for moving target in digital camera. Video stream in the camera is used for the moving target tracking. Particle filter is used to deal with problem of the target object's random movement and shape change. Color and edge features are used as measurement of the object's states. Parallel processing algorithm is developed to realize real-time particle filter object tracking easily in hardware environment of the digital camera. Movement prediction algorithm is also proposed to remove focus error caused by difference between tracking result and target object's real position when the photo is taken. Simulation and experiment results in digital camera demonstrate effectiveness of the proposed method. We embedded real-time object tracking algorithm in the digital camera. Position and distance of the moving target is obtained accurately by object tracking from the video stream. SIMD processor is applied to enforce parallel real-time processing. Processing time less than 60ms for each frame is obtained in the digital camera with its CPU of only 162MHz.

  16. Radiometric calibration of digital cameras using Gaussian processes

    NASA Astrophysics Data System (ADS)

    Schall, Martin; Grunwald, Michael; Umlauf, Georg; Franz, Matthias O.

    2015-05-01

    Digital cameras are subject to physical, electronic and optic effects that result in errors and noise in the image. These effects include for example a temperature dependent dark current, read noise, optical vignetting or different sensitivities of individual pixels. The task of a radiometric calibration is to reduce these errors in the image and thus improve the quality of the overall application. In this work we present an algorithm for radiometric calibration based on Gaussian processes. Gaussian processes are a regression method widely used in machine learning that is particularly useful in our context. Then Gaussian process regression is used to learn a temperature and exposure time dependent mapping from observed gray-scale values to true light intensities for each pixel. Regression models based on the characteristics of single pixels suffer from excessively high runtime and thus are unsuitable for many practical applications. In contrast, a single regression model for an entire image with high spatial resolution leads to a low quality radiometric calibration, which also limits its practical use. The proposed algorithm is predicated on a partitioning of the pixels such that each pixel partition can be represented by one single regression model without quality loss. Partitioning is done by extracting features from the characteristic of each pixel and using them for lexicographic sorting. Splitting the sorted data into partitions with equal size yields the final partitions, each of which is represented by the partition centers. An individual Gaussian process regression and model selection is done for each partition. Calibration is performed by interpolating the gray-scale value of each pixel with the regression model of the respective partition. The experimental comparison of the proposed approach to classical flat field calibration shows a consistently higher reconstruction quality for the same overall number of calibration frames.

  17. Digital Natives and Digital Immigrants: Teaching with Technology

    ERIC Educational Resources Information Center

    Martin, Ellen Marie Peterson

    2011-01-01

    Education is witnessing an increasing demand for technology use in the classroom. At the same time, new teachers are entering the profession in high numbers, some being labeled as "Digital Natives" while others are labeled "Digital Immigrants". This qualitative case study investigated the technology practices of Digital Native and Digital…

  18. Design and application of a digital array high-speed camera system

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Yao, Xuefeng; Ma, Yinji; Yuan, Yanan

    2016-03-01

    In this paper, a digital array high-speed camera system is designed and applied in dynamic fracture experiment. First, the design scheme for 3*3 array digital high-speed camera system is presented, including 3*3 array light emitting diode (LED) light source unit, 3*3 array charge coupled device (CCD) camera unit, timing delay control unit, optical imaging unit and impact loading unit. Second, the influence of geometric optical parameters on optical parallax is analyzed based on the geometric optical imaging mechanism. Finally, combining the method of dynamic caustics with the digital high-speed camera system, the dynamic fracture behavior of crack initiation and propagation in PMMA specimen under low-speed impact is investigated to verify the feasibility of the high-speed camera system.

  19. Remote detection of photoplethysmographic systolic and diastolic peaks using a digital camera.

    PubMed

    McDuff, Daniel; Gontarek, Sarah; Picard, Rosalind W

    2014-12-01

    We present a new method for measuring photoplethysmogram signals remotely using ambient light and a digital camera that allows for accurate recovery of the waveform morphology (from a distance of 3 m). In particular, we show that the peak-to-peak time between the systolic peak and diastolic peak/inflection can be automatically recovered using the second-order derivative of the remotely measured waveform. We compare measurements from the face with those captured using a contact fingertip sensor and show high agreement in peak and interval timings. Furthermore, we show that results can be significantly improved using orange, green, and cyan color channels compared to the tradition red, green, and blue channel combination. The absolute error in interbeat intervals was 26 ms and the absolute error in mean systolic-diastolic peak-to-peak times was 12 ms. The mean systolic-diastolic peak-to-peak times measured using the contact sensor and the camera were highly correlated, ρ = 0.94 (p 0.001). The results were obtained with a camera frame-rate of only 30 Hz. This technology has significant potential for advancing healthcare. PMID:25073159

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

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

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

  1. Issues in implementing services for a wireless web-enabled digital camera

    NASA Astrophysics Data System (ADS)

    Venkataraman, Shyam; Sampat, Nitin; Fisher, Yoram; Canosa, John; Noel, Nicholas

    2001-05-01

    The competition in the exploding digital photography market has caused vendors to explore new ways to increase their return on investment. A common view among industry analysts is that increasingly it will be services provided by these cameras, and not the cameras themselves, that will provide the revenue stream. These services will be coupled to e- Appliance based Communities. In addition, the rapidly increasing need to upload images to the Internet for photo- finishing services as well as the need to download software upgrades to the camera is driving many camera OEMs to evaluate the benefits of using the wireless web to extend their enterprise systems. Currently, creating a viable e- appliance such as a digital camera coupled with a wireless web service requires more than just a competency in product development. This paper will evaluate the system implications in the deployment of recurring revenue services and enterprise connectivity of a wireless, web-enabled digital camera. These include, among other things, an architectural design approach for services such as device management, synchronization, billing, connectivity, security, etc. Such an evaluation will assist, we hope, anyone designing or connecting a digital camera to the enterprise systems.

  2. Works starts on building world's largest digital camera

    NASA Astrophysics Data System (ADS)

    Kruesi, Liz

    2015-10-01

    The $473m Large Synoptic Survey Telescope (LSST) has moved one step closer to completion after the US Department of Energy (DOE) approved the start of construction for the telescope's $168m 3.2-gigapixel camera.

  3. Investigation of a consumer-grade digital stereo camera

    NASA Astrophysics Data System (ADS)

    Menna, Fabio; Nocerino, Erica; Remondino, Fabio; Shortis, Mark

    2013-04-01

    The paper presents a metric investigation of the Fuji FinePix Real 3D W1 stereo photo-camera. The stereo-camera uses a synchronized Twin Lens-CCD System to acquire simultaneously two images using two Fujinon 3x optical zoom lenses arranged in an aluminum die-cast frame integrated in a very compact body. The nominal baseline is 77 mm and the resolution of the each CCD is 10 megapixels. Given the short baseline and the presence of two optical paths, the investigation aims to evaluate the accuracy of the 3D data that can be produced and the stability of the camera. From a photogrammetric point of view, the interest in this camera is its capability to acquire synchronized image pairs that contain important 3D metric information for many close-range applications (human body parts measurement, rapid prototyping, surveying of archeological artifacts, etc.). Calibration values - for the left and right cameras - at different focal lengths, derived with an in-house software application, are reported together with accuracy analyses. The object coordinates obtained from the bundle adjustment computation for each focal length were compared to reference coordinates of a test range by means of a similarity transformation. Additionally, the article reports on the investigation of the asymmetrical relative orientation between the left and right camera.

  4. Direct digital conversion detector technology

    NASA Astrophysics Data System (ADS)

    Mandl, William J.; Fedors, Richard

    1995-06-01

    Future imaging sensors for the aerospace and commercial video markets will depend on low cost, high speed analog-to-digital (A/D) conversion to efficiently process optical detector signals. Current A/D methods place a heavy burden on system resources, increase noise, and limit the throughput. This paper describes a unique method for incorporating A/D conversion right on the focal plane array. This concept is based on Sigma-Delta sampling, and makes optimum use of the active detector real estate. Combined with modern digital signal processors, such devices will significantly increase data rates off the focal plane. Early conversion to digital format will also decrease the signal susceptibility to noise, lowering the communications bit error rate. Computer modeling of this concept is described, along with results from several simulation runs. A potential application for direct digital conversion is also reviewed. Future uses for this technology could range from scientific instruments to remote sensors, telecommunications gear, medical diagnostic tools, and consumer products.

  5. Digital holographic PTV for complicated flow in a water by two cameras and refractive index-matching method

    NASA Astrophysics Data System (ADS)

    Kuniyasu, Masataka; Aoyagi, Yusuke; Unno, Noriyuki; Satake, Shin-ichi; Yuki, Kazuhisa; Seki, Yohji

    2016-06-01

    A basic heat transfer promoter such as packed beds of spheres is one of the technologies of the promotion of heat transfer using the turbulent mixture. We carried out 3-D visualization of digital holographic PTV to understand the complicated flow in a sphere-packed pipe (SPP) using a refractive index-matching method with a water used as a working fluid, the spheres was made of MEXFLON, whose refractive index is the same as that of a water. To visualize the detail flow structure around the spheres in water, we performed three-dimensional simultaneous measurements of velocity field in a water flow in the SPP are performed by our proposed holography technique with two cameras. The velocity field by two cameras could obtain finer flow structures than that by one camera.

  6. Digital holographic PTV for complicated flow in a water by two cameras and refractive index-matching method

    NASA Astrophysics Data System (ADS)

    Kuniyasu, Masataka; Aoyagi, Yusuke; Unno, Noriyuki; Satake, Shin-ichi; Yuki, Kazuhisa; Seki, Yohji

    2016-03-01

    A basic heat transfer promoter such as packed beds of spheres is one of the technologies of the promotion of heat transfer using the turbulent mixture. We carried out 3-D visualization of digital holographic PTV to understand the complicated flow in a sphere-packed pipe (SPP) using a refractive index-matching method with a water used as a working fluid, the spheres was made of MEXFLON, whose refractive index is the same as that of a water. To visualize the detail flow structure around the spheres in water, we performed three-dimensional simultaneous measurements of velocity field in a water flow in the SPP are performed by our proposed holography technique with two cameras. The velocity field by two cameras could obtain finer flow structures than that by one camera.

  7. CAMAC interface for digitally recording infrared camera images

    NASA Astrophysics Data System (ADS)

    Dyer, G. R.

    1986-06-01

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

  8. Photogrammetry of a 5m Inflatable Space Antenna With Consumer Digital Cameras

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.; Giersch, Louis R.; Quagliaroli, Jessica M.

    2000-01-01

    This paper discusses photogrammetric measurements of a 5m-diameter inflatable space antenna using four Kodak DC290 (2.1 megapixel) digital cameras. The study had two objectives: 1) Determine the photogrammetric measurement precision obtained using multiple consumer-grade digital cameras and 2) Gain experience with new commercial photogrammetry software packages, specifically PhotoModeler Pro from Eos Systems, Inc. The paper covers the eight steps required using this hardware/software combination. The baseline data set contained four images of the structure taken from various viewing directions. Each image came from a separate camera. This approach simulated the situation of using multiple time-synchronized cameras, which will be required in future tests of vibrating or deploying ultra-lightweight space structures. With four images, the average measurement precision for more than 500 points on the antenna surface was less than 0.020 inches in-plane and approximately 0.050 inches out-of-plane.

  9. DigiCam: fully digital compact camera for SST-1M telescope

    NASA Astrophysics Data System (ADS)

    Aguilar, J. A.; Bilnik, W.; Bogacz, L.; Bulik, T.; Christov, A.; della Volpe, D.; Dyrda, M.; Frankowski, A.; Grudzinska, M.; Grygorczuk, J.; Heller, M.; Idźkowski, B.; Janiak, M.; Jamrozy, M.; Karczewski, M.; Kasperek, J.; Lyard, E.; Marszałek, A.; Michałowski, J.; Moderski, R.; Montaruli, T.; Neronov, A.; Nicolau-Kukliński, J.; Niemiec, J.; Ostrowski, M.; Paśko, P.; Płatos, Ł.; Prandini, E.; Pruchniewicz, R.; Rafalski, J.; Rajda, P. J.; Rameez, M.; Rataj, M.; Rupiński, M.; Rutkowski, K.; Seweryn, K.; Sidz, M.; Stawarz, Ł.; Stodulska, M.; Stodulski, M.; Tokarz, M.; Toscano, S.; Troyano Pujadas, I.; Walter, R.; Wawer, P.; Wawrzaszek, R.; Wiśniewski, L.; Zietara, K.; Ziółkowski, P.; Żychowski, P.

    2014-08-01

    The single mirror Small Size Telescopes (SST-1M), being built by a sub-consortium of Polish and Swiss Institutions of the CTA Consortium, will be equipped with a fully digital camera with a compact photodetector plane based on silicon photomultipliers. The internal trigger signal transmission overhead will be kept at low level by introducing a high level of integration. It will be achieved by massively deploying state-of-the-art multi-gigabit transceivers, beginning from the ADC flash converters, through the internal data and trigger signals transmission over backplanes and cables, to the camera's server 10Gb/s Ethernet links. Such approach will allow fitting the size and weight of the camera exactly to the SST-1M needs, still retaining the flexibility of a fully digital design. Such solution has low power consumption, high reliability and long lifetime. The concept of the camera will be described, along with some construction details and performance results.

  10. Technological Effects on Aesthetic Evaluation: Vermeer and the Camera Obscura

    ERIC Educational Resources Information Center

    Hantula, Donald A.; Sudduth, Mary Margaret; Clabaugh, Alison

    2009-01-01

    The question of whether an artist's use of technology to create art results in a detectable aesthetic difference was investigated in the case of Dutch realist painter Johannes Vermeer and his use of the camera obscura. In Experiment 1, participants evaluated 20 Vermeer paintings on 6 aesthetic dimensions and preferred paintings created with the…

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

    NASA Astrophysics Data System (ADS)

    Liang, Yubin; Qiu, Yan; Cui, Tiejun

    2016-06-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

  13. Digital Technology and Student Cognitive Development

    ERIC Educational Resources Information Center

    Cavanaugh, J. Michael; Giapponi, Catherine C.; Golden, Timothy D.

    2016-01-01

    Digital technology has proven a beguiling, some even venture addictive, presence in the lives of our 21st century (millennial) students. And while screen technology may offer select cognitive benefits, there is mounting evidence in the cognitive neuroscience literature that digital technology is restructuring the way our students read and think,…

  14. Digital synchroballistic schlieren camera for high-speed photography of bullets and rocket sleds

    NASA Astrophysics Data System (ADS)

    Buckner, Benjamin D.; L'Esperance, Drew

    2013-08-01

    A high-speed digital streak camera designed for simultaneous high-resolution color photography and focusing schlieren imaging is described. The camera uses a computer-controlled galvanometer scanner to achieve synchroballistic imaging through a narrow slit. Full color 20 megapixel images of a rocket sled moving at 480 m/s and of projectiles fired at around 400 m/s were captured, with high-resolution schlieren imaging in the latter cases, using conventional photographic flash illumination. The streak camera can achieve a line rate for streak imaging of up to 2.4 million lines/s.

  15. Estimation of spectral distribution of sky radiance using a commercial digital camera.

    PubMed

    Saito, Masanori; Iwabuchi, Hironobu; Murata, Isao

    2016-01-10

    Methods for estimating spectral distribution of sky radiance from images captured by a digital camera and for accurately estimating spectral responses of the camera are proposed. Spectral distribution of sky radiance is represented as a polynomial of the wavelength, with coefficients obtained from digital RGB counts by linear transformation. The spectral distribution of radiance as measured is consistent with that obtained by spectrometer and radiative transfer simulation for wavelengths of 430-680 nm, with standard deviation below 1%. Preliminary applications suggest this method is useful for detecting clouds and studying the relation between irradiance at the ground and cloud distribution. PMID:26835780

  16. Measurement of noises and modulation transfer function of cameras used in optical-digital correlators

    NASA Astrophysics Data System (ADS)

    Evtikhiev, Nikolay N.; Starikov, Sergey N.; Cheryomkhin, Pavel A.; Krasnov, Vitaly V.

    2012-01-01

    Hybrid optical-digital systems based on diffractive correlator are being actively developed. To correctly estimate application capabilities of cameras of different types in optical-digital correlation systems knowledge of modulation transfer function (MTF) and light depended temporal and spatial noises is required. The method for measurement of 2D MTF is presented. The method based on random target method but instead of a random target the specially created target with flat power spectrum is used. It allows to measure MTF without averaging 1D Fourier spectra over rows or columns as is in the random target method and to achieve all values of 2D MTF instead of just two orthogonal cross-sections. The simple method for measuring the dependence of camera temporal noise on light signal value by shooting a single scene is described. Measurements results of light and dark spatial and temporal noises of cameras are presented. Procedure for obtaining camera's light spatial noise portrait (array of PRNU values for all photo sensor pixels) is presented. Results on measurements of MTF and temporal and spatial noises for consumer photo camera, machine vision camera and videosurveillance camera are presented.

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

    NASA Astrophysics Data System (ADS)

    Yu, Liping; Pan, Bing

    2014-05-01

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

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

    NASA Technical Reports Server (NTRS)

    Friedman, Gary L.

    1994-01-01

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

  19. Lights, Camera, Reflection! Digital Movies: A Tool for Reflective Learning

    ERIC Educational Resources Information Center

    Genereux, Annie Prud'homme; Thompson, William A.

    2008-01-01

    At the end of a biology course entitled Ecology, Evolution, and Genetics, students were asked to consider how their learning experience had changed their perception of either ecology or genetics. Students were asked to express their thoughts in the form of a "digital story" using readily available software to create movies for the purpose of…

  20. Vegetation indices derived from a modified digital camera in combination with different blocking filters

    NASA Astrophysics Data System (ADS)

    Krainer, Karl; Hammerle, Albin; Wohlfahrt, Georg

    2015-04-01

    Remote and proximal sensing have become valuable and broadly used tools in ecosystem research. Radiation reflected and scattered at and from the vegetation is used to infer information about vegetation biomass, structure, vitality and functioning, just to name a few. To this end numerous vegetation indices have been established, which relate reflectance in different wavelengths to each other. While such indices are usually calculated from reflectance data measured by spectro-radiometers we did a study using a commercially available digital camera, from which the infrared (IR) band elimination filter was removed. By removing this filter, the camera sensor became sensitive for IR radiation besides the visible spectrum. Comparing measurements with this modified camera and a hyperspectral spectro-radiometer over different vegetation and surfaces we determined the potential of such a modified camera to measure different vegetation indices. To this end we compared 71 vegetation indices derived from spectro-radiometer data with 63 indices derived from the modified digital camera. We found that many of these different indices featured relatively high correlations. Especially the rgR (green/red ratio) and NDI (normalized difference vegetation index) calculated from data of the modified camera do correlate very well with vegetation indices that are known for representing the amount and vitality of green biomass, as these are the NIDI (normalized infrared vegetation index) and the LIC (curvature index). We thus conclude from this experiment, that given a proper inter-calibration, a commercially available digital camera can be modified and used as a reasonable alternative tool to determine vegetation biomass and/or vitality. In addition to these measurements currently different band elimination filters are used to improve the information content of the digital images.

  1. A powerful ethernet interface module for digital camera control

    NASA Astrophysics Data System (ADS)

    Amato, Stephen M.; Geary, John C.

    2012-09-01

    We have found a commercially-available ethernet interface module with sufficient on-board resources to largely handle all timing generation tasks required by digital imaging systems found in astronomy. In addition to providing a high-bandwidth ethernet interface to the controller, it can largely replace the need for special-purpose timing circuitry. Examples for use with both CCD and CMOS imagers are provided.

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

    USGS Publications Warehouse

    Light, D.L.

    1996-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Eliasson, Henrik

    2010-01-01

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

  4. Can Commercial Digital Cameras Be Used as Multispectral Sensors? A Crop Monitoring Test

    PubMed Central

    Lebourgeois, Valentine; Bégué, Agnès; Labbé, Sylvain; Mallavan, Benjamin; Prévot, Laurent; Roux, Bruno

    2008-01-01

    The use of consumer digital cameras or webcams to characterize and monitor different features has become prevalent in various domains, especially in environmental applications. Despite some promising results, such digital camera systems generally suffer from signal aberrations due to the on-board image processing systems and thus offer limited quantitative data acquisition capability. The objective of this study was to test a series of radiometric corrections having the potential to reduce radiometric distortions linked to camera optics and environmental conditions, and to quantify the effects of these corrections on our ability to monitor crop variables. In 2007, we conducted a five-month experiment on sugarcane trial plots using original RGB and modified RGB (Red-Edge and NIR) cameras fitted onto a light aircraft. The camera settings were kept unchanged throughout the acquisition period and the images were recorded in JPEG and RAW formats. These images were corrected to eliminate the vignetting effect, and normalized between acquisition dates. Our results suggest that 1) the use of unprocessed image data did not improve the results of image analyses; 2) vignetting had a significant effect, especially for the modified camera, and 3) normalized vegetation indices calculated with vignetting-corrected images were sufficient to correct for scene illumination conditions. These results are discussed in the light of the experimental protocol and recommendations are made for the use of these versatile systems for quantitative remote sensing of terrestrial surfaces.

  5. 75 FR 7519 - In the Matter of Certain Digital Cameras; Notice of Commission Determination Not To Review an...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... ] on February 27, 2009 and March 11, 2009. 74 FR 12377-78 (Mar. 24, 2009). The complaint, as... COMMISSION In the Matter of Certain Digital Cameras; Notice of Commission Determination Not To Review an... importation, or the sale within the United States after importation of certain digital cameras by reason...

  6. A Mid-infrared Digital Electronic Camera System for Assessing Natural Resources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water strongly absorbs mid-infrared (1300-2500 nm) radiation, resulting in this region of the spectrum being sensitive to the water content within features. Little information is available on using an electronic digital camera filtered to this region of the spectrum to assess natural resources. Th...

  7. Developing Mental Imagery Using a Digital Camera: A Study of Adult Vocational Training

    ERIC Educational Resources Information Center

    Ryba, Ken; Selby, Linda; Brown, Roy

    2004-01-01

    This study was undertaken to explore the use of a digital camera for mental imagery training of a vocational task with two young adult men with Down syndrome. The results indicate that these particular men benefited from the use of a collaborative training process that involved mental imagery for learning a series of photocopying operations. An…

  8. Estimating the Infrared Radiation Wavelength Emitted by a Remote Control Device Using a Digital Camera

    ERIC Educational Resources Information Center

    Catelli, Francisco; Giovannini, Odilon; Bolzan, Vicente Dall Agnol

    2011-01-01

    The interference fringes produced by a diffraction grating illuminated with radiation from a TV remote control and a red laser beam are, simultaneously, captured by a digital camera. Based on an image with two interference patterns, an estimate of the infrared radiation wavelength emitted by a TV remote control is made. (Contains 4 figures.)

  9. Digital Video Cameras for Brainstorming and Outlining: The Process and Potential

    ERIC Educational Resources Information Center

    Unger, John A.; Scullion, Vicki A.

    2013-01-01

    This "Voices from the Field" paper presents methods and participant-exemplar data for integrating digital video cameras into the writing process across postsecondary literacy contexts. The methods and participant data are part of an ongoing action-based research project systematically designed to bring research and theory into practice…

  10. On the Complexity of Digital Video Cameras in/as Research: Perspectives and Agencements

    ERIC Educational Resources Information Center

    Bangou, Francis

    2014-01-01

    The goal of this article is to consider the potential for digital video cameras to produce as part of a research agencement. Our reflection will be guided by the current literature on the use of video recordings in research, as well as by the rhizoanalysis of two vignettes. The first of these vignettes is associated with a short video clip shot by…

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

    NASA Astrophysics Data System (ADS)

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

    2010-11-01

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

  12. Development of an XYZ Digital Camera with Embedded Color Calibration System for Accurate Color Acquisition

    NASA Astrophysics Data System (ADS)

    Kretkowski, Maciej; Jablonski, Ryszard; Shimodaira, Yoshifumi

    Acquisition of accurate colors is important in the modern era of widespread exchange of electronic multimedia. The variety of device-dependent color spaces causes troubles with accurate color reproduction. In this paper we present the outlines of accomplished digital camera system with device-independent output formed from tristimulus XYZ values. The outstanding accuracy and fidelity of acquired color is achieved in our system by employing an embedded color calibration system based on emissive device generating reference calibration colors with user-defined spectral distribution and chromaticity coordinates. The system was tested by calibrating the camera using 24 reference colors spectrally reproduced from 24 color patches of the Macbeth Chart. The average color difference (CIEDE2000) has been found to be ΔE =0.83, which is an outstanding result compared to commercially available digital cameras.

  13. Integrating Digital Video Technology in the Classroom

    ERIC Educational Resources Information Center

    Lim, Jon; Pellett, Heidi Henschel; Pellett, Tracy

    2009-01-01

    Digital video technology can be a powerful tool for teaching and learning. It enables students to develop a variety of skills including research, communication, decision-making, problem-solving, and other higher-order critical-thinking skills. In addition, digital video technology has the potential to enrich university classroom curricula, enhance…

  14. A versatile digital camera trigger for telescopes in the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Schwanke, U.; Shayduk, M.; Sulanke, K.-H.; Vorobiov, S.; Wischnewski, R.

    2015-05-01

    This paper describes the concept of an FPGA-based digital camera trigger for imaging atmospheric Cherenkov telescopes, developed for the future Cherenkov Telescope Array (CTA). The proposed camera trigger is designed to select images initiated by the Cherenkov emission of extended air showers from very-high energy (VHE, E > 20 GeV) photons and charged particles while suppressing signatures from background light. The trigger comprises three stages. A first stage employs programmable discriminators to digitize the signals arriving from the camera channels (pixels). At the second stage, a grid of low-cost FPGAs is used to process the digitized signals for camera regions with 37 pixels. At the third stage, trigger conditions found independently in any of the overlapping 37-pixel regions are combined into a global camera trigger by few central FPGAs. Trigger prototype boards based on Xilinx FPGAs have been designed, built and tested and were shown to function properly. Using these components a full camera trigger with a power consumption and price per channel of about 0.5 W and 19 €, respectively, can be built. With the described design the camera trigger algorithm can take advantage of pixel information in both the space and the time domain allowing, for example, the creation of triggers sensitive to the time-gradient of a shower image; the time information could also be exploited to online adjust the time window of the acquisition system for pixel data. Combining the results of the parallel execution of different trigger algorithms (optimized, for example, for the lowest and highest energies, respectively) on each FPGA can result in a better response over all photons energies (as demonstrated by Monte Carlo simulation in this work).

  15. Comparison of Digital Surface Models for Snow Depth Mapping with Uav and Aerial Cameras

    NASA Astrophysics Data System (ADS)

    Boesch, R.; Bühler, Y.; Marty, M.; Ginzler, C.

    2016-06-01

    Photogrammetric workflows for aerial images have improved over the last years in a typically black-box fashion. Most parameters for building dense point cloud are either excessive or not explained and often the progress between software releases is poorly documented. On the other hand, development of better camera sensors and positional accuracy of image acquisition is significant by comparing product specifications. This study shows, that hardware evolutions over the last years have a much stronger impact on height measurements than photogrammetric software releases. Snow height measurements with airborne sensors like the ADS100 and UAV-based DSLR cameras can achieve accuracies close to GSD * 2 in comparison with ground-based GNSS reference measurements. Using a custom notch filter on the UAV camera sensor during image acquisition does not yield better height accuracies. UAV based digital surface models are very robust. Different workflow parameter variations for ADS100 and UAV camera workflows seem to have only random effects.

  16. Metric Potential of a 3D Measurement System Based on Digital Compact Cameras

    PubMed Central

    Sanz-Ablanedo, Enoc; Rodríguez-Pérez, José Ramón; Arias-Sánchez, Pedro; Armesto, Julia

    2009-01-01

    This paper presents an optical measuring system based on low cost, high resolution digital cameras. Once the cameras are synchronised, the portable and adjustable system can be used to observe living beings, bodies in motion, or deformations of very different sizes. Each of the cameras has been modelled individually and studied with regard to the photogrammetric potential of the system. We have investigated the photogrammetric precision obtained from the crossing of rays, the repeatability of results, and the accuracy of the coordinates obtained. Systematic and random errors are identified in validity assessment of the definition of the precision of the system from crossing of rays or from marking residuals in images. The results have clearly demonstrated the capability of a low-cost multiple-camera system to measure with sub-millimetre precision. PMID:22408520

  17. Digital Photography and Journals in a Kindergarten-First-Grade Classroom: Toward Meaningful Technology Integration in Early Childhood Education

    ERIC Educational Resources Information Center

    Ching, Cynthia Carter; Wang, X. Christine; Shih, Mei-Li; Kedem, Yore

    2006-01-01

    To explore meaningful and effective technology integration in early childhood education, we investigated how kindergarten-first-grade students created and employed digital photography journals to support social and cognitive reflection. These students used a digital camera to document their daily school activities and created digital photo…

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

    NASA Astrophysics Data System (ADS)

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

    1991-06-01

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

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

    NASA Astrophysics Data System (ADS)

    Hijazi, A.; Madhavan, V.

    2008-08-01

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

  20. Chemistry on Camera: Integrating Technology into the Science Laboratory.

    ERIC Educational Resources Information Center

    Hargis, Jace; Stehr, Jim

    2001-01-01

    Describes a relevant, innovative laboratory exercise that promotes the construction of ideas that can be used to further science processing. Integrates technology in the form of digital photography, a portable computer, and a projection device. This activity fits well in a high school chemistry class. (SAH)

  1. Digital scanner infrared focal plane technology

    NASA Astrophysics Data System (ADS)

    Ortiz, M. A.; Malone, N. R.; Harris, M.; Shin, J.; Byers, S.; Price, D.; Vampola, J.

    2011-09-01

    Advancements in finer geometry and technology advancements in circuit design now allow placement of digital architecture on cryogenic focal planes while using less power than heritage analog designs. These advances in technology reduce the size, weight, and power of modern focal planes. In addition, the interface to the focal plane is significantly simplified and is more immune to Electromagnetic Interference (EMI). The cost of the customer's instrument after integration with the digital scanning Focal Plane Array (FPA) has been significantly reduced by placing digital architecture such as Analog to digital convertors and Low Voltage Differential Signaling (LVDS) Inputs and Outputs (I/O) on the Read Out Integrated Circuit (ROIC).

  2. Using a Digital Camera to Teach Physically Challenged Students.

    ERIC Educational Resources Information Center

    Wassmuth, Birgit L.

    1998-01-01

    Describes how an innovative application of new technology, in a Graphics of Journalism course, not only accommodated a physically challenged student but empowered her to fully participate in the learning process, and allowed her discover and develop talents and skills that may lead to career opportunities not previously imagined. (SR)

  3. Illuminant spectrum estimation using a digital color camera and a color chart

    NASA Astrophysics Data System (ADS)

    Shi, Junsheng; Yu, Hongfei; Huang, Xiaoqiao; Chen, Zaiqing; Tai, Yonghang

    2014-10-01

    Illumination estimation is the main step in color constancy processing, also an important prerequisite for digital color image reproduction and many computer vision applications. In this paper, a method for estimating illuminant spectrum is investigated using a digital color camera and a color chart under the situation when the spectral reflectance of the chart is known. The method is based on measuring CIEXYZ of the chart using the camera. The first step of the method is to gain camera's color correction matrix and gamma values by taking a photo of the chart under a standard illuminant. The second step is to take a photo of the chart under an estimated illuminant, and the camera's inherent RGB values are converted to the standard sRGB values and further converted to CIEXYZ of the chart. Based on measured CIEXYZ and known spectral reflectance of the chart, the spectral power distribution (SPD) of the illuminant is estimated using the Wiener estimation and smoothing estimation. To evaluate the performance of the method quantitatively, the goodnessfitting coefficient (GFC) was used to measure the spectral match and the CIELAB color difference metric was used to evaluate the color match between color patches under the estimated and actual SPDs. The simulated experiment was carried to estimate CIE standard illuminant D50 and C using X-rite ColorChecker 24-color chart, the actual experiment was carried to estimate daylight and illuminant A using two consumergrade cameras and the chart, and the experiment results verified feasible of the investigated method.

  4. Reading Out Single-Molecule Digital RNA and DNA Isothermal Amplification in Nanoliter Volumes with Unmodified Camera Phones.

    PubMed

    Rodriguez-Manzano, Jesus; Karymov, Mikhail A; Begolo, Stefano; Selck, David A; Zhukov, Dmitriy V; Jue, Erik; Ismagilov, Rustem F

    2016-03-22

    Digital single-molecule technologies are expanding diagnostic capabilities, enabling the ultrasensitive quantification of targets, such as viral load in HIV and hepatitis C infections, by directly counting single molecules. Replacing fluorescent readout with a robust visual readout that can be captured by any unmodified cell phone camera will facilitate the global distribution of diagnostic tests, including in limited-resource settings where the need is greatest. This paper describes a methodology for developing a visual readout system for digital single-molecule amplification of RNA and DNA by (i) selecting colorimetric amplification-indicator dyes that are compatible with the spectral sensitivity of standard mobile phones, and (ii) identifying an optimal ratiometric image-process for a selected dye to achieve a readout that is robust to lighting conditions and camera hardware and provides unambiguous quantitative results, even for colorblind users. We also include an analysis of the limitations of this methodology, and provide a microfluidic approach that can be applied to expand dynamic range and improve reaction performance, allowing ultrasensitive, quantitative measurements at volumes as low as 5 nL. We validate this methodology using SlipChip-based digital single-molecule isothermal amplification with λDNA as a model and hepatitis C viral RNA as a clinically relevant target. The innovative combination of isothermal amplification chemistry in the presence of a judiciously chosen indicator dye and ratiometric image processing with SlipChip technology allowed the sequence-specific visual readout of single nucleic acid molecules in nanoliter volumes with an unmodified cell phone camera. When paired with devices that integrate sample preparation and nucleic acid amplification, this hardware-agnostic approach will increase the affordability and the distribution of quantitative diagnostic and environmental tests. PMID:26900709

  5. Temporal monitoring of groundcover change using digital cameras

    NASA Astrophysics Data System (ADS)

    Zerger, A.; Gobbett, D.; Crossman, C.; Valencia, P.; Wark, T.; Davies, M.; Handcock, R. N.; Stol, J.

    2012-10-01

    This paper describes the development and testing of an automated method for detecting change in groundcover vegetation in response to kangaroo grazing using visible wavelength digital photography. The research is seen as a precursor to the future deployment of autonomous vegetation monitoring systems (environmental sensor networks). The study was conducted over six months with imagery captured every 90 min and post-processed using supervised image processing techniques. Synchronous manual assessments of groundcover change were also conducted to evaluate the effectiveness of the automated procedures. Results show that for particular cover classes such as Live Vegetation and Bare Ground, there is excellent temporal concordance between automated and manual methods. However, litter classes were difficult to consistently differentiate. A limitation of the method is the inability to effectively deal with change in the vertical profile of groundcover. This indicates that the three dimensional structure related to species composition and plant traits play an important role in driving future experimental designs. The paper concludes by providing lessons for conducting future groundcover monitoring experiments.

  6. Comparison of fractional vegetation cover derived from digital camera and MODIS NDVI in Mongolia

    NASA Astrophysics Data System (ADS)

    Jaebeom, K.; Jang, K.; Kang, S.

    2014-12-01

    Satellite remote sensing can continuously observe the land surface vegetation with repetitive error over large area, though it requires complex processes to correct errors occurred from atmosphere and topography. On the other hand, the imageries captured by digital camera provide several benefits such as high spatial resolution, simple shooting method, and relatively low-priced instrument. Furthermore, digital camera has less of atmospheric effect such as path radiance than satellite imagery, and have advantage of the shooting with actual land cover. The objective of this study is the comparison of fractional vegetation cover derived from digital camera and MODIS Normalized Difference Vegetation Index (NDVI) in Mongolia. 670 imageries for the above ground including green leaves and soil surface captured by digital camera at the 134 sites in Mongolia from 2011 to 2014 were used to classify the vegetation cover fraction. Thirteen imageries captured by Mongolia and South Korea were selected to determine the best classification method. Various classification methods including the 4 supervised classifications, 2 unsupervised classifications, and histogram methods were used to separate the green vegetation in camera imageries that were converted to two color spaces such as Red-Green-Blue (RGB) and Hue-Intensity-Saturation (HIS). Those results were validated using the manually counted dataset from the local plant experts. The maximum likelihood classification (MLC) with HIS color space among classification methods showed a good agreement with manually counted dataset. The correlation coefficient and the root mean square error were 1.008 and 7.88%, respectively. Our preliminary result indicates that the MLC with HIS color space has a potential to classify the green vegetation in Mongolia.

  7. Combining laser scan and photogrammetry for 3D object modeling using a single digital camera

    NASA Astrophysics Data System (ADS)

    Xiong, Hanwei; Zhang, Hong; Zhang, Xiangwei

    2009-07-01

    In the fields of industrial design, artistic design and heritage conservation, physical objects are usually digitalized by reverse engineering through some 3D scanning methods. Laser scan and photogrammetry are two main methods to be used. For laser scan, a video camera and a laser source are necessary, and for photogrammetry, a digital still camera with high resolution pixels is indispensable. In some 3D modeling tasks, two methods are often integrated to get satisfactory results. Although many research works have been done on how to combine the results of the two methods, no work has been reported to design an integrated device at low cost. In this paper, a new 3D scan system combining laser scan and photogrammetry using a single consumer digital camera is proposed. Nowadays there are many consumer digital cameras, such as Canon EOS 5D Mark II, they usually have features of more than 10M pixels still photo recording and full 1080p HD movie recording, so a integrated scan system can be designed using such a camera. A square plate glued with coded marks is used to place the 3d objects, and two straight wood rulers also glued with coded marks can be laid on the plate freely. In the photogrammetry module, the coded marks on the plate make up a world coordinate and can be used as control network to calibrate the camera, and the planes of two rulers can also be determined. The feature points of the object and the rough volume representation from the silhouettes can be obtained in this module. In the laser scan module, a hand-held line laser is used to scan the object, and the two straight rulers are used as reference planes to determine the position of the laser. The laser scan results in dense points cloud which can be aligned together automatically through calibrated camera parameters. The final complete digital model is obtained through a new a patchwise energy functional method by fusion of the feature points, rough volume and the dense points cloud. The design

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

    NASA Astrophysics Data System (ADS)

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

    2007-02-01

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

  9. ESPI of a transient shock wave flow using an ultrafast digital camera

    NASA Astrophysics Data System (ADS)

    Andrag, Roland; Barbosa, Filipe J.; Skews, Beric W.

    2001-04-01

    The application of electronic speckle pattern interferometry (ESPI) to the visualization of a typical high-speed compressible flow is investigated. ESPI is an interferometric technique that has established itself as a reliable alternative to holographic interferometry in the measurement of small displacements and of vibrations, and is increasingly being used in flow visualization. It can instantly and in real time produce interferometric images in digital form on a video screen, with no photographic processing being required. In this paper two flows are examined, the one a low speed flow of a thermal plume arising from a hot soldering iron, for which real-time visualization is achievable; and the other single frame imaging of a shockwave emerging from a small round open- ended shock tube. ESPI is shown to be a valuable tool in the visualization of compressible flows, and a good alternative to holographic interferometry in obtaining quantitative density data about a flow field. A method for obtaining interferograms with finite fringe-width is presented. The main benefit of using ESPI for flow visualization is that the interferometric image is immediately accessible for viewing on a monitor, so avoiding the tedious photographic holographic reconstruction process. Advances in camera technology are fast overcoming its disadvantage, low image resolution.

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

    NASA Astrophysics Data System (ADS)

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

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

  11. Low-cost conversion of the Polaroid MD-4 land camera to a digital gel documentation system.

    PubMed

    Porch, Timothy G; Erpelding, John E

    2006-04-30

    A simple, inexpensive design is presented for the rapid conversion of the popular MD-4 Polaroid land camera to a high quality digital gel documentation system. Images of ethidium bromide stained DNA gels captured using the digital system were compared to images captured on Polaroid instant film. Resolution and sensitivity were enhanced using the digital system. In addition to the low cost and superior image quality of the digital system, there is also the added convenience of real-time image viewing through the swivel LCD of the digital camera, wide flexibility of gel sizes, accurate automatic focusing, variable image resolution, and consistent ease of use and quality. Images can be directly imported to a computer by using the USB port on the digital camera, further enhancing the potential of the digital system for documentation, analysis, and archiving. The system is appropriate for use as a start-up gel documentation system and for routine gel analysis. PMID:16472866

  12. Digital microscopy. Bringing new technology into focus.

    PubMed

    2010-06-01

    Digital microscopy enables the scanning of microscope slides so that they can be viewed, analyzed, and archived on a computer. While the technology is not yet widely accepted by pathologists, a switch to digital microscopy systems seems to be inevitable in the near future. PMID:21309285

  13. Digitizing Technologies for Preservation. SPEC Kit 214.

    ERIC Educational Resources Information Center

    Kellerman, L. Suzanne, Comp.; Wilson, Rebecca, Comp.

    The Association of Research Libraries distributed a survey to its 119 member libraries to assess the use of state-of-the-art digital technologies as a preservation method. Libraries were asked to report detailed data on all projects designed specifically to: (1) enhance images of faded or brittle originals, (2) provide access to digital images…

  14. Georeferencing airborne images from a multiple digital camera system by GPS/INS

    NASA Astrophysics Data System (ADS)

    Mostafa, Mohamed Mohamed Rashad

    2000-10-01

    In this thesis, the development and testing of an airborne fully digital multi-sensor system for kinematic mapping is presented. The system acquires two streams of data, namely navigation data and imaging data. The navigation data are obtained by integrating an accurate strapdown Inertial Navigation System with two GPS receivers. The imaging data are acquired by two digital cameras, configured in such a way so as to reduce their geometric limitations. The two digital cameras capture strips of overlapping nadir and oblique images. The INS/GPS-derived trajectory contains the full translational and rotational motion of the carrier aircraft. Thus, image exterior orientation information is extracted from the trajectory, during postprocessing. This approach eliminates the need for ground control when computing 3D positions of objects that appear in the field of view of the system imaging component. Test flights were conducted over the campus of The University of Calgary. Two approaches for calibrating the system are presented, namely pre-mission calibration and in-flight calibration. Testing the system in flight showed that best ground point positioning accuracy at 1:12000 average image scale is 0.2 m (RMS) in easting and northing and 0.3 m (RMS) in height. Preliminary results indicate that major applications of such a system in the future are in the field of digital mapping, at scales of 1:10000 and smaller, and the generation of digital elevation models for engineering applications.

  15. Digital image georeferencing from a multiple camera system by GPS/INS

    NASA Astrophysics Data System (ADS)

    Mostafa, Mohamed M. R.; Schwarz, Klaus-Peter

    In this paper, the development and testing of an airborne fully digital multi-sensor system for digital mapping data acquisition is presented. The system acquires two streams of data, namely, navigation (georeferencing) data and imaging data. The navigation data are obtained by integrating an accurate strapdown inertial navigation system with a differential GPS system (DGPS). The imaging data are acquired by two low-cost digital cameras, configured in such a way so as to reduce their geometric limitations. The two cameras capture strips of overlapping nadir and oblique images. The GPS/INS-derived trajectory contains the full translational and rotational motion of the carrier aircraft. Thus, image exterior orientation information is extracted from the trajectory, during post-processing. This approach eliminates the need for ground control (GCP) when computing 3D positions of objects that appear in the field of view of the system imaging component. Two approaches for calibrating the system are presented, namely, terrestrial calibration and in-flight calibration. Test flights were conducted over the campus of The University of Calgary. Testing the system showed that best ground point positioning accuracy at 1:12,000 average image scale is 0.2 m (RMS) in easting and northing and 0.3 m (RMS) in height. Preliminary results indicate that major applications of such a system in the future are in the field of digital mapping, at scales of 1:5000 and smaller, and in the generation of digital elevation models for engineering applications.

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

    NASA Astrophysics Data System (ADS)

    Hsia, Shih-Chang; Tsai, Po-Shien

    2011-04-01

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

  17. A digital underwater video camera system for aquatic research in regulated rivers

    USGS Publications Warehouse

    Martin, Benjamin M.; Irwin, Elise R.

    2010-01-01

    We designed a digital underwater video camera system to monitor nesting centrarchid behavior in the Tallapoosa River, Alabama, 20 km below a peaking hydropower dam with a highly variable flow regime. Major components of the system included a digital video recorder, multiple underwater cameras, and specially fabricated substrate stakes. The innovative design of the substrate stakes allowed us to effectively observe nesting redbreast sunfish Lepomis auritus in a highly regulated river. Substrate stakes, which were constructed for the specific substratum complex (i.e., sand, gravel, and cobble) identified at our study site, were able to withstand a discharge level of approximately 300 m3/s and allowed us to simultaneously record 10 active nests before and during water releases from the dam. We believe our technique will be valuable for other researchers that work in regulated rivers to quantify behavior of aquatic fauna in response to a discharge disturbance.

  18. Semantic evaluation of high-resolution low-cost digital camera data for urban classification

    NASA Astrophysics Data System (ADS)

    Frangesch, Alexander; Greiwe, Ansgar; Ehlers, Manfred

    2005-10-01

    Many applications of remote sensing - like, for example, urban monitoring - require high resolution image data for a correct determination of object geometry. The desired geometry of an object's surface is created in dieffernet studies by use of well known segmentation techniques. In this study, we evaluate the influence on image quality of analog and digital image data on the results of a image segmentation in eCognition. We compare the suitability of analog middle format camera data with image data produced by a commercial "of the shelf" digital camera taken during two campaigns in 2003 and 2004. Furthermore, the results of a multiresolution classification of an urban test site by use of both datasets will be presented. An outlook for future work on a multiresolution data fusion with hyperspectral data will be given at the end of this paper.

  19. High Speed and Slow Motion: The Technology of Modern High Speed Cameras

    ERIC Educational Resources Information Center

    Vollmer, Michael; Mollmann, Klaus-Peter

    2011-01-01

    The enormous progress in the fields of microsystem technology, microelectronics and computer science has led to the development of powerful high speed cameras. Recently a number of such cameras became available as low cost consumer products which can also be used for the teaching of physics. The technology of high speed cameras is discussed,…

  20. Measuring the Orbital Period of the Moon Using a Digital Camera

    ERIC Educational Resources Information Center

    Hughes, Stephen W.

    2006-01-01

    A method of measuring the orbital velocity of the Moon around the Earth using a digital camera is described. Separate images of the Moon and stars taken 24 hours apart were loaded into Microsoft PowerPoint and the centre of the Moon marked on each image. Four stars common to both images were connected together to form a "home-made" constellation.…

  1. Monitoring of phenological control on ecosystem fluxes using digital cameras and eddy covariance data

    NASA Astrophysics Data System (ADS)

    Toomey, M. P.; Friedl, M. A.; Hufkens, K.; Sonnentag, O.; Milliman, T. E.; Frolking, S.; Richardson, A. D.

    2012-12-01

    Digital repeat photography is an emerging platform for monitoring land surface phenology. Despite the great potential of digital repeat photography to yield insights into phenological cycles, relatively few studies have compared digital repeat photography to in situ measures of ecosystem fluxes. We used 60 site years of concurrent camera and eddy covariance data at 13 sites, representing five distinct ecosystem types - temperate deciduous forest, temperate coniferous forest, boreal forest, grasslands and crops - to measure and model phenological controls on carbon and water exchange with the atmosphere. Camera-derived relative greenness was strongly correlated with estimated gross primary productivity among the five ecosystem types and was moderately correlated with water fluxes. Camera-derived canopy development was also compared with phenological phase as predicted by a generalized, bioclimatic phenology model and Moderate Resolution Imaging Spectrometer (MODIS) imagery to assess the potential for cross-biome phenological monitoring. This study demonstrates the potential of webcam networks such as Phenocam (phenocam.unh.edu) to conduct long-term, continental monitoring and modeling of ecosystem response to climate change.

  2. Photonic networks that exploit digital coherent technologies

    NASA Astrophysics Data System (ADS)

    Mori, Yojiro; Sato, Ken-ichi

    2013-12-01

    The emergence of digital coherent optical transmission technologies is being eagerly awaited by the world. This enables us to develop spectrally-efficient transmission systems by means of polarization-division multiplexing and multilevelmodulation formats such as quadrature-phase-shift keying (QPSK) and higher-order quadrature-amplitude modulation (QAM). Thanks to recent rapid advances in the research and development of electronics, demodulation of such signals can be realized effectively by utilizing sophisticated digital signal processors (DSPs). Such digital coherent technologies have successfully been implemented in commercial systems. However, the transmission performance of photonic networks is limited by system impairments that include crosstalk and spectrum narrowing caused at reconfigurable optical add/drop multiplexers (ROADMs) and the nonlinearity of optical fibers. Current digital coherent technologies do not resolve these problems comprehensively necessitating further research. In this paper, we investigate the impacts of the system impairments through intensive computer simulations and show the maximum transmission distances of multilevel-modulation signals. Various transmission schemes for gridless networks including Nyquist wavelengthdivision- multiplexing (WDM) networks, which need digital coherent technologies, are evaluated. We also discuss DSP algorithms that suit photonic networks and permit digital coherent technologies to become more effective in realizing future networks.

  3. Tweens' Characterization of Digital Technologies

    ERIC Educational Resources Information Center

    Brito, Pedro Quelhas

    2012-01-01

    The tweens are a transitional age group undergoing deep physical and psychological transformations. Based on a thirteen-focus group research design involving 103 students, and applying a tweens-centered approach, the characteristics of SMS, IM, Internet, digital photos, electronic games, and email were analyzed. Categories such as moral issues,…

  4. Use of a Digital Camera to Monitor the Growth and Nitrogen Status of Cotton

    PubMed Central

    Jia, Biao; He, Haibing; Ma, Fuyu; Diao, Ming; Jiang, Guiying; Zheng, Zhong; Cui, Jin; Fan, Hua

    2014-01-01

    The main objective of this study was to develop a nondestructive method for monitoring cotton growth and N status using a digital camera. Digital images were taken of the cotton canopies between emergence and full bloom. The green and red values were extracted from the digital images and then used to calculate canopy cover. The values of canopy cover were closely correlated with the normalized difference vegetation index and the ratio vegetation index and were measured using a GreenSeeker handheld sensor. Models were calibrated to describe the relationship between canopy cover and three growth properties of the cotton crop (i.e., aboveground total N content, LAI, and aboveground biomass). There were close, exponential relationships between canopy cover and three growth properties. And the relationships for estimating cotton aboveground total N content were most precise, the coefficients of determination (R2) value was 0.978, and the root mean square error (RMSE) value was 1.479 g m−2. Moreover, the models were validated in three fields of high-yield cotton. The result indicated that the best relationship between canopy cover and aboveground total N content had an R2 value of 0.926 and an RMSE value of 1.631 g m−2. In conclusion, as a near-ground remote assessment tool, digital cameras have good potential for monitoring cotton growth and N status. PMID:24723817

  5. Greenness indices from digital cameras predict the timing and seasonal dynamics of canopy-scale photosynthesis.

    PubMed

    Toomey, Michael; Friedl, Mark A; Frolking, Steve; Hufkens, Koen; Klosterman, Stephen; Sonnentag, Oliver; Baldocchi, Dennis D; Bernacchi, Carl J; Biraud, Sebastien C; Bohrer, Gil; Brzostek, Edward; Burns, Sean P; Coursolle, Carole; Hollinger, David Y; Margolis, Hank A; Mccaughey, Harry; Monson, Russell K; Munger, J William; Pallardy, Stephen; Phillips, Richard P; Torn, Margaret S; Wharton, Sonia; Zeri, Marcelo; And, Andrew D; Richardson, Andrew D

    2015-01-01

    The proliferation of digital cameras co-located with eddy covariance instrumentation provides new opportunities to better understand the relationship between canopy phenology and the seasonality of canopy photosynthesis. In this paper we analyze the abilities and limitations of canopy color metrics measured by digital repeat photography to track seasonal canopy development and photosynthesis, determine phenological transition dates, and estimate intra-annual and interannual variability in canopy photosynthesis. We used 59 site-years of camera imagery and net ecosystem exchange measurements from 17 towers spanning three plant functional types (deciduous broadleaf forest, evergreen needleleaf forest, and grassland/crops) to derive color indices and estimate gross primary productivity (GPP). GPP was strongly correlated with greenness derived from camera imagery in all three plant functional types. Specifically, the beginning of the photosynthetic period in deciduous broadleaf forest and grassland/crops and the end of the photosynthetic period in grassland/crops were both correlated with changes in greenness; changes in redness were correlated with the end of the photosynthetic period in deciduous broadleaf forest. However, it was not possible to accurately identify the beginning or ending of the photosynthetic period using camera greenness in evergreen needleleaf forest. At deciduous broadleaf sites, anomalies in integrated greenness and total GPP were significantly correlated up to 60 days after the mean onset date for the start of spring. More generally, results from this work demonstrate that digital repeat photography can be used to quantify both the duration of the photosynthetically active period as well as total GPP in deciduous broadleaf forest and grassland/crops, but that new and different approaches are required before comparable results can be achieved in evergreen needleleaf forest. PMID:26255360

  6. A simple method for vignette correction of airborne digital camera data

    SciTech Connect

    Nguyen, A.T.; Stow, D.A.; Hope, A.S.

    1996-11-01

    Airborne digital camera systems have gained popularity in recent years due to their flexibility, high geometric fidelity and spatial resolution, and fast data turn-around time. However, a common problem that plagues these types of framing systems is vignetting which causes falloff in image brightness away from principle nadir point. This paper presents a simple method for vignetting correction by utilizing laboratory images of a uniform illumination source. Multiple lab images are averaged and inverted to create digital correction templates which then are applied to actual airborne data. The vignette correction was effective in removing the systematic falloff in spectral values. We have shown that the vignette correction is a necessary part of the preprocessing of raw digital airborne remote sensing data. The consequences of not correcting for these effects are demonstrated in the context of monitoring of salt marsh habitat. 4 refs.

  7. Technology Counts 2007: A Digital Decade

    ERIC Educational Resources Information Center

    Education Week, 2007

    2007-01-01

    "Technology Counts 2007" looks back, and ahead, after a decade of enormous upheaval in the educational technology landscape. This special issue of "Education Week" includes the following articles: (1) A Digital Decade; (2) Getting Up to Speed (Andrew Trotter); (3) E-Rate's Imprint Seen in Schools (Andrew Trotter); (4) Teaching Assistants (Rhea R.…

  8. Digital technology in the orthodontic laboratory.

    PubMed

    Hurt, Arlen J

    2012-02-01

    Four relatively new technologies are now key in orthodontic specialty laboratories: digital photography, laser welding, computer-aided design/computer-aided manufacturing, and intraoral scanners. The purposes of this article are to briefly describe these technologies and to explain how they are used in the orthodontic laboratory. PMID:22284293

  9. CMOS digital pixel sensors: technology and applications

    NASA Astrophysics Data System (ADS)

    Skorka, Orit; Joseph, Dileepan

    2014-04-01

    CMOS active pixel sensor technology, which is widely used these days for digital imaging, is based on analog pixels. Transition to digital pixel sensors can boost signal-to-noise ratios and enhance image quality, but can increase pixel area to dimensions that are impractical for the high-volume market of consumer electronic devices. There are two main approaches to digital pixel design. The first uses digitization methods that largely rely on photodetector properties and so are unique to imaging. The second is based on adaptation of a classical analog-to-digital converter (ADC) for in-pixel data conversion. Imaging systems for medical, industrial, and security applications are emerging lower-volume markets that can benefit from these in-pixel ADCs. With these applications, larger pixels are typically acceptable, and imaging may be done in invisible spectral bands.

  10. Digital Camera Calibration Using Images Taken from AN Unmanned Aerial Vehicle

    NASA Astrophysics Data System (ADS)

    Pérez, M.; Agüera, F.; Carvajal, F.

    2011-09-01

    For calibrating the camera, an accurate determination of the interior orientation parameters is needed. For more accurate results, the calibration images should be taken under conditions that are similar to the field samples. The aim of this work is the establishment of an efficient and accurate digital camera calibration method to be used in particular working conditions, as it can be found with our UAV (Unmanned Aerial Vehicle) photogrammetric projects. The UAV used in this work was md4-200 modelled by Microdrones. The microdrone is also equipped with a standard digital non- metric camera, the Pentax Optio A40 camera. To find out the interior orientation parameters of the digital camera, two calibration methods were done. A lab calibration based on a flat pattern and a field calibration were fulfilled. To carry out the calibration, Photomodeler Scanner software was used in both cases. The lab calibration process was completely automatic using a calibration grid. The focal length was fixed at widest angle and the network included a total of twelve images with± 90º roll angles. In order to develop the field calibration, a flight plan was programmed including a total of twelve images. In the same way as in the lab calibration, the focal length was fixed at widest angle. The field test used in the study was a flat surface located on the University of Almería campus and a set of 67 target points were placed. The calibration field area was 25 × 25 m approximately and the altitude flight over ground was 50 m. After the software processing, the camera calibration parameter values were obtained. The paper presents the process, the results and the accuracy of these calibration methods. The field calibration method reduced the final total error obtained in the previous lab calibration. Furthermore the overall RMSs obtained from both methods are similar. Therefore we will apply the field calibration results to all our photogrammetric projects in which the flight high

  11. Digital technology and the conservation of nature.

    PubMed

    Arts, Koen; van der Wal, René; Adams, William M

    2015-11-01

    Digital technology is changing nature conservation in increasingly profound ways. We describe this impact and its significance through the concept of 'digital conservation', which we found to comprise five pivotal dimensions: data on nature, data on people, data integration and analysis, communication and experience, and participatory governance. Examining digital innovation in nature conservation and addressing how its development, implementation and diffusion may be steered, we warn against hypes, techno-fix thinking, good news narratives and unverified assumptions. We identify a need for rigorous evaluation, more comprehensive consideration of social exclusion, frameworks for regulation and increased multi-sector as well as multi-discipline awareness and cooperation. Along the way, digital technology may best be reconceptualised by conservationists from something that is either good or bad, to a dual-faced force in need of guidance. PMID:26508352

  12. Camera model and calibration process for high-accuracy digital image metrology of inspection planes

    NASA Astrophysics Data System (ADS)

    Correia, Bento A. B.; Dinis, Joao

    1998-10-01

    High accuracy digital image based metrology must rely on an integrated model of image generation that is able to consider simultaneously the geometry of the camera vs. object positioning, and the conversion of the optical image on the sensor into an electronic digital format. In applications of automated visual inspection involving the analysis of approximately plane objects these models are generally simplified in order to facilitate the process of camera calibration. In this context, the lack of rigor in the determination of the intrinsic parameters in such models is particularly relevant. Aiming at the high accuracy metrology of contours of objects lying on an analysis plane, and involving sub-pixel measurements, this paper presents a three-stage camera model that includes an extrinsic component of perspective distortion and the intrinsic components of radial lens distortion and sensor misalignment. The later two factors are crucial in applications of machine vision that rely on the use of low cost optical components. A polynomial model for the negative radial lens distortion of wide field of view CCTV lenses is also established.

  13. Application of multimode airborne digital camera system in Wenchuan earthquake disaster monitoring

    NASA Astrophysics Data System (ADS)

    Liu, Xue; Li, Qingting; Fang, Junyong; Tong, Qingxi; Zheng, Lanfen

    2009-06-01

    Remote sensing, especially airborne remote sensing, can be an invaluable technique for quick response to natural disasters. Timely acquired images by airborne remote sensing can provide very important information for the headquarters and decision makers to be aware of the disaster situation, and make effective relief arrangements. The image acquisition and processing of Multi-mode Airborne Digital Camera System (MADC) and its application in Wenchuan earthquake disaster monitoring are presented in this paper. MADC system is a novel airborne digital camera developed by Institute of Remote Sensing Applications, Chinese Academy of Sciences. This camera system can acquire high quality images in three modes, namely wide field, multi-spectral (hyper-spectral) and stereo conformation. The basic components and technical parameters of MADC are also presented in this paper. MADC system played a very important role in the disaster monitoring of Wenchuan earthquake. In particular, the map of dammed lakes in Jianjiang river area was produced and provided to the front line headquarters. Analytical methods and information extraction techniques of MADC are introduced. Some typical analytical and imaging results are given too. Suggestions for the design and configuration of the airborne sensors are discussed at the end of this paper.

  14. Digital optical tape: Technology and standardization issues

    NASA Technical Reports Server (NTRS)

    Podio, Fernando L.

    1996-01-01

    During the coming years, digital data storage technologies will continue an aggressive growth to satisfy the user's need for higher storage capacities, higher data transfer rates and long-term archival media properties. Digital optical tape is a promising technology to satisfy these user's needs. As any emerging data storage technology, the industry faces many technological and standardization challenges. The technological challenges are great, but feasible to overcome. Although it is too early to consider formal industry standards, the optical tape industry has decided to work together by initiating prestandardization efforts that may lead in the future to formal voluntary industry standards. This paper will discuss current industry optical tape drive developments and the types of standards that will be required for the technology. The status of current industry prestandardization efforts will also be discussed.

  15. Improvements in remote cardiopulmonary measurement using a five band digital camera.

    PubMed

    McDuff, Daniel; Gontarek, Sarah; Picard, Rosalind W

    2014-10-01

    Remote measurement of the blood volume pulse via photoplethysmography (PPG) using digital cameras and ambient light has great potential for healthcare and affective computing. However, traditional RGB cameras have limited frequency resolution. We present results of PPG measurements from a novel five band camera and show that alternate frequency bands, in particular an orange band, allowed physiological measurements much more highly correlated with an FDA approved contact PPG sensor. In a study with participants (n = 10) at rest and under stress, correlations of over 0.92 (p 0.01) were obtained for heart rate, breathing rate, and heart rate variability measurements. In addition, the remotely measured heart rate variability spectrograms closely matched those from the contact approach. The best results were obtained using a combination of cyan, green, and orange (CGO) bands; incorporating red and blue channel observations did not improve performance. In short, RGB is not optimal for this problem: CGO is better. Incorporating alternative color channel sensors should not increase the cost of such cameras dramatically. PMID:24835124

  16. The cryogenic multiplexer and shift register for submillimeter-wave digital camera

    NASA Astrophysics Data System (ADS)

    Hibi, Yasunori; Matsuo, Hiroshi; Arai, Hideaki; Nagata, Hirohisa; Ikeda, Hirokazu; Fujiwara, Mikio

    2009-11-01

    We have been developing cryogenic readout integrate circuits using SONY GaAs JFETs for large format arrays of high impedance type detectors especially for submillimeter/terahertz astronomy. The GaAs JFETs manufactured by SONY CO. Ltd have excellent static properties at less than 1 K. Besides, these JFETs have good performance for electrical switches; they have very low gate capacitance (<50 fF), low on resistance (˜10 kΩ), and high off resistance (>100 TΩ). To realize a cryogenic readout system for submillimeter-wave/terahertz camera, we designed multiplexers with sample-and-holds and shift registers. We report the first test results of each circuit and show prospect of a cryogenic multiplex system for a submillimeter-wave/terahertz digital camera.

  17. Technique for improving the quality of images from digital cameras using ink-jet printers and smoothed RGB transfer curves

    NASA Astrophysics Data System (ADS)

    Sampat, Nitin; Grim, John F.; O'Hara, James E.

    1998-04-01

    The digital camera market is growing at an explosive rate. At the same time, the quality of photographs printed on ink- jet printers continues to improve. Most of the consumer cameras are designed with the monitor as the target output device and ont the printer. When a user is printing his images from a camera, he/she needs to optimize the camera and printer combination in order to maximize image quality. We describe the details of one such method for improving image quality using a AGFA digital camera and an ink jet printer combination. Using Adobe PhotoShop, we generated optimum red, green and blue transfer curves that match the scene content to the printers output capabilities. Application of these curves to the original digital image resulted in a print with more shadow detail, no loss of highlight detail, a smoother tone scale, and more saturated colors. The image also exhibited an improved tonal scale and visually more pleasing images than those captured and printed without any 'correction'. While we report the results for one camera-printer combination we tested this technique on numbers digital cameras and printer combinations and in each case produced a better looking image. We also discuss the problems we encountered in implementing this technique.

  18. "I Know How Much This Child Has Learned. I Have Proof!": Employing Digital Technologies for Documentation Processes in Kindergarten

    ERIC Educational Resources Information Center

    Boardman, Margot

    2007-01-01

    This study set out to investigate the use of digital cameras and voice recorders to accurately capture essential components of early learners' achievements. The project was undertaken by 29 early childhood educators within kindergarten settings in Tasmania and the Australian Capital Territory. Data collected indicated that digital technologies,…

  19. Instrument-quality digital camera that transitioned to low-cost high-volume production

    NASA Astrophysics Data System (ADS)

    Mandl, William J.

    2002-12-01

    MOSAD(copyright), Multiplexed OverSample Analog to Digital conversion, is a low power on focal plane analog to digital, A/D, process that places an oversample A/D at each pixel site. Two full custom designs for a visible light staring array were developed with this approach. One design approach uses a silicon photo diode in combination with photo gates at the pixel and the other approach uses an all photo gate sensor for detection. Both arrays were designed with a 320x240 format with the pixels placed on 16 micron centers. The system includes the camera assembly, driver interface assembly, a frame grabber board with integrated decimator and Windows 2000 compatible software for real time image display. The camera includes the sensor, either photo gate or photo diode, mounted on a PC card with support electronics. A custom lens mount attaches the camera to C or CS mount lens. Testing was done with a Tamron 13VM2812 CCTV CS mount lens. Both an RS644 and an RS422 parallel interface card assembly was developed to attach to the frame grabber board. The final iteration cameras were tested at the Amain facility and pictures were taken. At 400 samples per second, measured on chip power consumption is under 10 milliwatts. Noise measurements at sample rates from 400 samples per second to 1,600 samples per second were taken for both parts. The photo diode worked and produced images but it had a sense amplifier problem that prevented adequate noise measurement. At 28 times oversample, the photo gate achieved typical 9 to 11 bits signal to noise with best case measured at 13 bits. Nonuniformity variation was below the noise floor.

  20. Assessment of digital camera-derived vegetation indices in quantitative monitoring of seasonal rice growth

    NASA Astrophysics Data System (ADS)

    Sakamoto, Toshihiro; Shibayama, Michio; Kimura, Akihiko; Takada, Eiji

    2011-11-01

    A commercially available digital camera can be used in a low-cost automatic observation system for monitoring crop growth change in open-air fields. We developed a prototype Crop Phenology Recording System (CPRS) for monitoring rice growth, but the ready-made waterproof cases that we used produced shadows on the images. After modifying the waterproof cases, we repeated the fixed-point camera observations to clarify questions regarding digital camera-derived vegetation indices (VIs), namely, the visible atmospherically resistant index (VARI) based on daytime normal color images (RGB image) and the nighttime relative brightness index (NRBI NIR) based on nighttime near infrared (NIR) images. We also took frequent measurements of agronomic data such as plant length, leaf area index (LAI), and aboveground dry matter weight to gain a detailed understanding of the temporal relationship between the VIs and the biophysical parameters of rice. In addition, we conducted another nighttime outdoor experiment to establish the link between NRBI NIR and camera-to-object distance. The study produced the following findings. (1) The customized waterproof cases succeeded in preventing large shadows from being cast, especially on nighttime images, and it was confirmed that the brightness of the nighttime NIR images had spatial heterogeneity when a point light source (flashlight) was used, in contrast to the daytime RGB images. (2) The additional experiment using a forklift showed that both the ISO sensitivity and the calibrated digital number of the NIR (cDN NIR) had significant effects on the sensitivity of NRBI NIR to the camera-to-object distance. (3) Detailed measurements of a reproductive stem were collected to investigate the connection between the morphological feature change caused by the panicle sagging process and the downtrend in NRBI NIR during the reproductive stages. However, these agronomic data were not completely in accord with NRBI NIR in terms of the temporal pattern

  1. Digital imaging technology assessment: Digital document storage project

    NASA Technical Reports Server (NTRS)

    1989-01-01

    An ongoing technical assessment and requirements definition project is examining the potential role of digital imaging technology at NASA's STI facility. The focus is on the basic components of imaging technology in today's marketplace as well as the components anticipated in the near future. Presented is a requirement specification for a prototype project, an initial examination of current image processing at the STI facility, and an initial summary of image processing projects at other sites. Operational imaging systems incorporate scanners, optical storage, high resolution monitors, processing nodes, magnetic storage, jukeboxes, specialized boards, optical character recognition gear, pixel addressable printers, communications, and complex software processes.

  2. Determination of the diffusion coefficient between corn syrup and distilled water using a digital camera

    NASA Astrophysics Data System (ADS)

    Ray, E.; Bunton, P.; Pojman, J. A.

    2007-10-01

    A simple technique for determining the diffusion coefficient between two miscible liquids is presented based on observing concentration-dependent ultraviolet-excited fluorescence using a digital camera. The ultraviolet-excited visible fluorescence of corn syrup is proportional to the concentration of the syrup. The variation of fluorescence with distance from the transition zone between the fluids is fit by the Fick's law solution to the diffusion equation. By monitoring the concentration at successive times, the diffusion coefficient can be determined in otherwise transparent materials. The technique is quantitative and makes measurement of diffusion accessible in the advanced undergraduate physics laboratory.

  3. Cataract screening by minimally trained remote observer with non-mydriatic digital fundus camera

    NASA Astrophysics Data System (ADS)

    Choi, Ann; Hjelmstad, David; Taibl, Jessica N.; Sayegh, Samir I.

    2013-03-01

    We propose a method that allows an inexperienced observer, through the examination of the digital fundus image of a retina on a computer screen, to simply determine the presence of a cataract and the necessity to refer the patient for further evaluation. To do so, fundus photos obtained with a non-mydriatic camera were presented to an inexperienced observer that was briefly instructed on fundus imaging, nature of cataracts and their probable effect on the image of the retina and the use of a computer program presenting fundus image pairs. Preliminary results of pair testing indicate the method is very effective.

  4. Conversion from light to numerical signal in a digital camera pipeline

    NASA Astrophysics Data System (ADS)

    Toadere, Florin

    2010-11-01

    The goal of this paper is to simulate the conversion from light to numerical signal which occurs during the image propagations through the digital camera pipeline. We focus on the spectral and resolution analysis of the optical system, the Bayer sampling, the photon shot and fixed pattern noise, the high dynamic range image, the amplitude and bilateral filters and the analog to digital conversion. The image capture system consists of a flash illumination source, a Cooke triplet photographic objective and a passive pixel CMOS sensor. We use a spectral image in order to simulate the illumination and the propagation of the light through the optical system components. The Fourier optics is used to compute the point spread function specific to each optical component. We consider the image acquisition system to be linear shift invariant and axial. The light propagation is orthogonal to the system.

  5. Continuous-wave terahertz digital holography by use of a pyroelectric array camera.

    PubMed

    Ding, Sheng-Hui; Li, Qi; Li, Yun-Da; Wang, Qi

    2011-06-01

    Terahertz (THz) digital holography is realized based on a 2.52 THz far-IR gas laser and a commercial 124 × 124 pyroelectric array camera. Off-axis THz holograms are obtained by recording interference patterns between light passing through the sample and the reference wave. A numerical reconstruction process is performed to obtain the field distribution at the object surface. Different targets were imaged to test the system's imaging capability. Compared with THz focal plane images, the image quality of the reconstructed images are improved a lot. The results show that the system's imaging resolution can reach at least 0.4 mm. The system also has the potential for real-time imaging application. This study confirms that digital holography is a promising technique for real-time, high-resolution THz imaging, which has extensive application prospects. PMID:21633426

  6. Mobile technology and the digitization of healthcare.

    PubMed

    Bhavnani, Sanjeev P; Narula, Jagat; Sengupta, Partho P

    2016-05-01

    The convergence of science and technology in our dynamic digital era has resulted in the development of innovative digital health devices that allow easy and accurate characterization in health and disease. Technological advancements and the miniaturization of diagnostic instruments to modern smartphone-connected and mobile health (mHealth) devices such as the iECG, handheld ultrasound, and lab-on-a-chip technologies have led to increasing enthusiasm for patient care with promises to decrease healthcare costs and to improve outcomes. This 'hype' for mHealth has recently intersected with the 'real world' and is providing important insights into how patients and practitioners are utilizing digital health technologies. It is also raising important questions regarding the evidence supporting widespread device use. In this state-of-the-art review, we assess the current literature of mHealth and aim to provide a framework for the advances in mHealth by understanding the various device, patient, and clinical factors as they relate to digital health from device designs and patient engagement, to clinical workflow and device regulation. We also outline new strategies for generation and analysis of mHealth data at the individual and population-based levels. PMID:26873093

  7. DIGITAL TECHNOLOGY BUSINESS CASE METHODOLOGY GUIDE & WORKBOOK

    SciTech Connect

    Thomas, Ken; Lawrie, Sean; Hart, Adam; Vlahoplus, Chris

    2014-09-01

    Performance advantages of the new digital technologies are widely acknowledged, but it has proven difficult for utilities to derive business cases for justifying investment in these new capabilities. Lack of a business case is often cited by utilities as a barrier to pursuing wide-scale application of digital technologies to nuclear plant work activities. The decision to move forward with funding usually hinges on demonstrating actual cost reductions that can be credited to budgets and thereby truly reduce O&M or capital costs. Technology enhancements, while enhancing work methods and making work more efficient, often fail to eliminate workload such that it changes overall staffing and material cost requirements. It is critical to demonstrate cost reductions or impacts on non-cost performance objectives in order for the business case to justify investment by nuclear operators. This Business Case Methodology approaches building a business case for a particular technology or suite of technologies by detailing how they impact an operator in one or more of the three following areas: Labor Costs, Non-Labor Costs, and Key Performance Indicators (KPIs). Key to those impacts will be identifying where the savings are “harvestable,” meaning they result in an actual reduction in headcount and/or cost. The report consists of a Digital Technology Business Case Methodology Guide and an accompanying spreadsheet workbook that will enable the user to develop a business case.

  8. The PANOPTES project: discovering exoplanets with low-cost digital cameras

    NASA Astrophysics Data System (ADS)

    Guyon, Olivier; Walawender, Josh; Jovanovic, Nemanja; Butterfield, Mike; Gee, Wilfred T.; Mery, Rawad

    2014-07-01

    The Panoptic Astronomical Networked OPtical observatory for Transiting Exoplanets Survey (PANOPTES, www.projectpanoptes.org) project is aimed at identifying transiting exoplanets using a wide network of low-cost imaging units. Each unit consists of two commercial digital single lens reflex (DSLR) cameras equipped with 85mm F1.4 lenses, mounted on a small equatorial mount. At a few $1000s per unit, the system offers a uniquely advantageous survey eficiency for the cost, and can easily be assembled by amateur astronomers or students. Three generations of prototype units have so far been tested, and the baseline unit design, which optimizes robustness, simplicity and cost, is now ready to be duplicated. We describe the hardware and software for the PANOPTES project, focusing on key challenging aspects of the project. We show that obtaining high precision photometric measurements with commercial DSLR color cameras is possible, using a PSF-matching algorithm we developed for this project. On-sky tests show that percent-level photometric precision is achieved in 1 min with a single camera. We also discuss hardware choices aimed at optimizing system robustness while maintaining adequate cost. PANOPTES is both an outreach project and a scientifically compelling survey for transiting exoplanets. In its current phase, experienced PANOPTES members are deploying a limited number of units, acquiring the experience necessary to run the network. A much wider community will then be able to participate to the project, with schools and citizen scientists integrating their units in the network.

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

    NASA Astrophysics Data System (ADS)

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

    1996-09-01

    A high resolution computer-controlled CCD image capturing system is developed by using a 12 bits 1024 by 1024 pixels CCD camera and motorized RGB filters to grasp an image with color depth up to 36 bits. The filters distinguish the major components of color and collect them separately while the CCD camera maintains the spatial resolution and detector filling factor. The color separation can be done optically rather than electronically. The operation is simply by placing the capturing objects like color photos, slides and even x-ray transparencies under the camera system, the necessary parameters such as integration time, mixing level and light intensity are automatically adjusted by an on-line expert system. This greatly reduces the restrictions of the capturing species. This unique approach can save considerable time for adjusting the quality of image, give much more flexibility of manipulating captured object even if it is a 3D object with minimal setup fixers. In addition, cross sectional dimension of a 3D capturing object can be analyzed by adapting a fiber optic ring light source. It is particularly useful in non-contact metrology of a 3D structure. The digitized information can be stored in an easily transferable format. Users can also perform a special LUT mapping automatically or manually. Applications of the system include medical images archiving, printing quality control, 3D machine vision, and etc.

  10. Performance of low-cost X-ray area detectors with consumer digital cameras

    NASA Astrophysics Data System (ADS)

    Panna, A.; Gomella, A. A.; Harmon, K. J.; Chen, P.; Miao, H.; Bennett, E. E.; Wen, H.

    2015-05-01

    We constructed X-ray detectors using consumer-grade digital cameras coupled to commercial X-ray phosphors. Several detector configurations were tested against the Varian PaxScan 3024M (Varian 3024M) digital flat panel detector. These include consumer cameras (Nikon D800, Nikon D700, and Nikon D3X) coupled to a green emission phosphor in a back-lit, normal incidence geometry, and in a front-lit, oblique incidence geometry. We used the photon transfer method to evaluate detector sensitivity and dark noise, and the edge test method to evaluate their spatial resolution. The essential specifications provided by our evaluation include discrete charge events captured per mm2 per unit exposure surface dose, dark noise in equivalents of charge events per pixel, and spatial resolution in terms of the full width at half maximum (FWHM) of the detector`s line spread function (LSF). Measurements were performed using a tungsten anode X-ray tube at 50 kVp. The results show that the home-built detectors provide better sensitivity and lower noise than the commercial flat panel detector, and some have better spatial resolution. The trade-off is substantially smaller imaging areas. Given their much lower costs, these home-built detectors are attractive options for prototype development of low-dose imaging applications.

  11. Using the auxiliary camera for system calibration of 3D measurement by digital speckle

    NASA Astrophysics Data System (ADS)

    Xue, Junpeng; Su, Xianyu; Zhang, Qican

    2014-06-01

    The study of 3D shape measurement by digital speckle temporal sequence correlation have drawn a lot of attention by its own advantages, however, the measurement mainly for depth z-coordinate, horizontal physical coordinate (x, y) are usually marked as image pixel coordinate. In this paper, a new approach for the system calibration is proposed. With an auxiliary camera, we made up the temporary binocular vision system, which are used for the calibration of horizontal coordinates (mm) while the temporal sequence reference-speckle-sets are calibrated. First, the binocular vision system has been calibrated using the traditional method. Then, the digital speckles are projected on the reference plane, which is moved by equal distance in the direction of depth, temporal sequence speckle images are acquired with camera as reference sets. When the reference plane is in the first position and final position, crossed fringe pattern are projected to the plane respectively. The control points of pixel coordinates are extracted by Fourier analysis from the images, and the physical coordinates are calculated by the binocular vision. The physical coordinates corresponding to each pixel of the images are calculated by interpolation algorithm. Finally, the x and y corresponding to arbitrary depth value z are obtained by the geometric formula. Experiments prove that our method can fast and flexibly measure the 3D shape of an object as point cloud.

  12. Application Of A 1024X1024 Pixel Digital Image Store, With Pulsed Progressive Readout Camera, For Gastro-Intestinal Radiology

    NASA Astrophysics Data System (ADS)

    Edmonds, E. W.; Rowlands, J. A.; Hynes, D. M.; Toth, B. D.; Porter, A. J.

    1986-06-01

    We discuss the applicability of intensified x-ray television systems for general digital radiography and the requirements necessary for physician acceptance. Television systems for videofluorography when limited to conventional fluoroscopic exposure rates (25uR/s to x-ray intensifier), with particular application to the gastro-intestinal system, all suffer from three problems which tend to degrade the image: (a) lack of resolution, (b) noise, and (c) patient movement. The system to be described in this paper addresses each of these problems. Resolution is that provided by the use of a 1024 x 1024 pixel frame store combined with a 1024 line video camera and a 10"/6" x-ray image intensifier. Problems of noise and sensitivity to patient movement are overcome by using a short but intense burst of radiation to produce the latent image, which is then read off the video camera in a progressive fashion and placed in the digital store. Hard copy is produced from a high resolution multiformat camera, or a high resolution digital laser camera. It is intended that this PPR system will replace the 100mm spot film camera in present use, and will provide information in digital form for further processing and eventual digital archiving.

  13. Cloud Height Estimation with a Single Digital Camera and Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Carretas, Filipe; Janeiro, Fernando M.

    2014-05-01

    Clouds influence the local weather, the global climate and are an important parameter in the weather prediction models. Clouds are also an essential component of airplane safety when visual flight rules (VFR) are enforced, such as in most small aerodromes where it is not economically viable to install instruments for assisted flying. Therefore it is important to develop low cost and robust systems that can be easily deployed in the field, enabling large scale acquisition of cloud parameters. Recently, the authors developed a low-cost system for the measurement of cloud base height using stereo-vision and digital photography. However, due to the stereo nature of the system, some challenges were presented. In particular, the relative camera orientation requires calibration and the two cameras need to be synchronized so that the photos from both cameras are acquired simultaneously. In this work we present a new system that estimates the cloud height between 1000 and 5000 meters. This prototype is composed by one digital camera controlled by a Raspberry Pi and is installed at Centro de Geofísica de Évora (CGE) in Évora, Portugal. The camera is periodically triggered to acquire images of the overhead sky and the photos are downloaded to the Raspberry Pi which forwards them to a central computer that processes the images and estimates the cloud height in real time. To estimate the cloud height using just one image requires a computer model that is able to learn from previous experiences and execute pattern recognition. The model proposed in this work is an Artificial Neural Network (ANN) that was previously trained with cloud features at different heights. The chosen Artificial Neural Network is a three-layer network, with six parameters in the input layer, 12 neurons in the hidden intermediate layer, and an output layer with only one output. The six input parameters are the average intensity values and the intensity standard deviation of each RGB channel. The output

  14. Portable retinal imaging for eye disease screening using a consumer-grade digital camera

    NASA Astrophysics Data System (ADS)

    Barriga, Simon; Larichev, Andrey; Zamora, Gilberto; Soliz, Peter

    2012-03-01

    The development of affordable means to image the retina is an important step toward the implementation of eye disease screening programs. In this paper we present the i-RxCam, a low-cost, hand-held, retinal camera for widespread applications such as tele-retinal screening for eye diseases like diabetic retinopathy (DR), glaucoma, and age-related ocular diseases. Existing portable retinal imagers do not meet the requirements of a low-cost camera with sufficient technical capabilities (field of view, image quality, portability, battery power, and ease-of-use) to be distributed widely to low volume clinics, such as the offices of single primary care physicians serving rural communities. The i-RxCam uses a Nikon D3100 digital camera body. The camera has a CMOS sensor with 14.8 million pixels. We use a 50mm focal lens that gives a retinal field of view of 45 degrees. The internal autofocus can compensate for about 2D (diopters) of focusing error. The light source is an LED produced by Philips with a linear emitting area that is transformed using a light pipe to the optimal shape at the eye pupil, an annulus. To eliminate corneal reflex we use a polarization technique in which the light passes through a nano-wire polarizer plate. This is a novel type of polarizer featuring high polarization separation (contrast ratio of more than 1000) and very large acceptance angle (>45 degrees). The i-RxCam approach will yield a significantly more economical retinal imaging device that would allow mass screening of the at-risk population.

  15. Payette National Forest aerial survey project using the Kodak digital color infrared camera

    NASA Astrophysics Data System (ADS)

    Greer, Jerry D.

    1997-11-01

    Staff of the Payette National Forest located in central Idaho used the Kodak Digital Infrared Camera to collect digital photographic images over a wide variety of selected areas. The objective of this aerial survey project is to collect airborne digital camera imagery and to evaluate it for potential use in forest assessment and management. The data collected from this remote sensing system is being compared with existing resource information and with personal knowledge of the areas surveyed. Resource specialists are evaluating the imagery to determine if it may be useful for; identifying cultural sites (pre-European settlement tribal villages and camps); recognizing ecosystem landscape pattern; mapping recreation areas; evaluating the South Fork Salmon River road reconstruction project; designing the Elk Summit Road; assessing the impact of sediment on anadramous fish in the South Fork Salmon River; assessing any contribution of sediment to the South Fork from the reconstructed road; determining post-wildfire stress development in conifer timber; in assessing the development of insect populations in areas initially determined to be within low intensity wildfire burn polygons; and to search for Idaho Ground Squirrel habitat. Project sites include approximately 60 linear miles of the South Fork of the Salmon River; a parallel road over about half that distance; 3 archaeological sites; two transects of about 6 miles each for landscape patterns; 3 recreation areas; 5 miles of the Payette River; 4 miles of the Elk Summit Road; a pair of transects 4.5 miles long for stress assessment in timber; a triplet of transects about 3 miles long for the assessment of the identification of species; and an area of about 640 acres to evaluate habitat for the endangered Idaho Ground Squirrel. Preliminary results indicate that the imagery is an economically viable way to collect site specific resource information that is of value in the management of a national forest.

  16. Estimating the spatial position of marine mammals based on digital camera recordings

    PubMed Central

    Hoekendijk, Jeroen P A; de Vries, Jurre; van der Bolt, Krissy; Greinert, Jens; Brasseur, Sophie; Camphuysen, Kees C J; Aarts, Geert

    2015-01-01

    Estimating the spatial position of organisms is essential to quantify interactions between the organism and the characteristics of its surroundings, for example, predator–prey interactions, habitat selection, and social associations. Because marine mammals spend most of their time under water and may appear at the surface only briefly, determining their exact geographic location can be challenging. Here, we developed a photogrammetric method to accurately estimate the spatial position of marine mammals or birds at the sea surface. Digital recordings containing landscape features with known geographic coordinates can be used to estimate the distance and bearing of each sighting relative to the observation point. The method can correct for frame rotation, estimates pixel size based on the reference points, and can be applied to scenarios with and without a visible horizon. A set of R functions was written to process the images and obtain accurate geographic coordinates for each sighting. The method is applied to estimate the spatiotemporal fine-scale distribution of harbour porpoises in a tidal inlet. Video recordings of harbour porpoises were made from land, using a standard digital single-lens reflex (DSLR) camera, positioned at a height of 9.59 m above mean sea level. Porpoises were detected up to a distance of ∽3136 m (mean 596 m), with a mean location error of 12 m. The method presented here allows for multiple detections of different individuals within a single video frame and for tracking movements of individuals based on repeated sightings. In comparison with traditional methods, this method only requires a digital camera to provide accurate location estimates. It especially has great potential in regions with ample data on local (a)biotic conditions, to help resolve functional mechanisms underlying habitat selection and other behaviors in marine mammals in coastal areas. PMID:25691982

  17. Estimating the spatial position of marine mammals based on digital camera recordings.

    PubMed

    Hoekendijk, Jeroen P A; de Vries, Jurre; van der Bolt, Krissy; Greinert, Jens; Brasseur, Sophie; Camphuysen, Kees C J; Aarts, Geert

    2015-02-01

    Estimating the spatial position of organisms is essential to quantify interactions between the organism and the characteristics of its surroundings, for example, predator-prey interactions, habitat selection, and social associations. Because marine mammals spend most of their time under water and may appear at the surface only briefly, determining their exact geographic location can be challenging. Here, we developed a photogrammetric method to accurately estimate the spatial position of marine mammals or birds at the sea surface. Digital recordings containing landscape features with known geographic coordinates can be used to estimate the distance and bearing of each sighting relative to the observation point. The method can correct for frame rotation, estimates pixel size based on the reference points, and can be applied to scenarios with and without a visible horizon. A set of R functions was written to process the images and obtain accurate geographic coordinates for each sighting. The method is applied to estimate the spatiotemporal fine-scale distribution of harbour porpoises in a tidal inlet. Video recordings of harbour porpoises were made from land, using a standard digital single-lens reflex (DSLR) camera, positioned at a height of 9.59 m above mean sea level. Porpoises were detected up to a distance of ∽3136 m (mean 596 m), with a mean location error of 12 m. The method presented here allows for multiple detections of different individuals within a single video frame and for tracking movements of individuals based on repeated sightings. In comparison with traditional methods, this method only requires a digital camera to provide accurate location estimates. It especially has great potential in regions with ample data on local (a)biotic conditions, to help resolve functional mechanisms underlying habitat selection and other behaviors in marine mammals in coastal areas. PMID:25691982

  18. Characterization of digital cameras for reflected ultraviolet photography; implications for qualitative and quantitative image analysis during forensic examination.

    PubMed

    Garcia, Jair E; Wilksch, Philip A; Spring, Gale; Philp, Peta; Dyer, Adrian

    2014-01-01

    Reflected ultraviolet imaging techniques allow for the visualization of evidence normally outside the human visible spectrum. Specialized digital cameras possessing extended sensitivity can be used for recording reflected ultraviolet radiation. Currently, there is a lack of standardized methods for ultraviolet image recording and processing using digital cameras, potentially limiting the implementation and interpretation. A methodology is presented for processing ultraviolet images based on linear responses and the sensitivity of the respective color channels. The methodology is applied to a FujiS3 UVIR camera, and a modified Nikon D70s camera, to reconstruct their respective spectral sensitivity curves between 320 and 400 nm. This method results in images with low noise and high contrast, suitable for qualitative and/or quantitative analysis. The application of this methodology is demonstrated in the recording of latent fingerprints. PMID:24117678

  19. Realization of the FPGA based TDI algorithm in digital domain for CMOS cameras

    NASA Astrophysics Data System (ADS)

    Tao, Shuping; Jin, Guang; Zhang, Xuyan; Qu, Hongsong

    2012-10-01

    In order to make the CMOS image sensors suitable for space high resolution imaging applications, a new method realizing TDI in digital domain by FPGA is proposed in this paper, which improves the imaging mode for area array CMOS sensors. The TDI algorithm accumulates the corresponding pixels of adjoining frames in digital domain, so the gray values increase by M times, where M is for the integration number, and the image's quality in signal-to-noise ratio can be improved. In addition, the TDI optimization algorithm is discussed. Firstly, the signal storage is optimized by 2 slices of external RAM, where memory depth expanding and the table tennis operation mechanism are used. Secondly, the FIFO operation mechanism reduces the reading and writing operation on memory by M×(M-1) times, It saves so much signal transfer time as is proportional to the square of integration number M2, that the frame frequency is able to increase greatly. At last, the CMOS camera based on TDI in digital domain is developed, and the algorithm is validated by experiments on it.

  20. Combining multi-spectral proximal sensors and digital cameras for monitoring grazed tropical pastures

    NASA Astrophysics Data System (ADS)

    Handcock, R. N.; Gobbett, D. L.; González, L. A.; Bishop-Hurley, G. J.; McGavin, S. L.

    2015-11-01

    Timely and accurate monitoring of pasture biomass and ground-cover is necessary in livestock production systems to ensure productive and sustainable management of forage for livestock. Interest in the use of proximal sensors for monitoring pasture status in grazing systems has increased, since such sensors can return data in near real-time, and have the potential to be deployed on large properties where remote sensing may not be suitable due to issues such as spatial scale or cloud cover. However, there are unresolved challenges in developing calibrations to convert raw sensor data to quantitative biophysical values, such as pasture biomass or vegetation ground-cover, to allow meaningful interpretation of sensor data by livestock producers. We assessed the use of multiple proximal sensors for monitoring tropical pastures with a pilot deployment of sensors at two sites on Lansdown Research Station near Townsville, Australia. Each site was monitored by a Skye SKR-four-band multi-spectral sensor (every 1 min), a digital camera (every 30 min), and a soil moisture sensor (every 1 min), each operated over 18 months. Raw data from each sensor were processed to calculate a number of multispectral vegetation indices. Visual observations of pasture characteristics, including above-ground standing biomass and ground cover, were made every 2 weeks. A methodology was developed to manage the sensor deployment and the quality control of the data collected. The data capture from the digital cameras was more reliable than the multi-spectral sensors, which had up to 63 % of data discarded after data cleaning and quality control. We found a strong relationship between sensor and pasture measurements during the wet season period of maximum pasture growth (January to April), especially when data from the multi-spectral sensors were combined with weather data. RatioNS34 (a simple band ratio between the near infrared (NIR) and lower shortwave infrared (SWIR) bands) and rainfall since 1

  1. A compact high-definition low-cost digital stereoscopic video camera for rapid robotic surgery development.

    PubMed

    Carlson, Jay; Kowalczuk, Jędrzej; Psota, Eric; Pérez, Lance C

    2012-01-01

    Robotic surgical platforms require vision feedback systems, which often consist of low-resolution, expensive, single-imager analog cameras. These systems are retooled for 3D display by simply doubling the cameras and outboard control units. Here, a fully-integrated digital stereoscopic video camera employing high-definition sensors and a class-compliant USB video interface is presented. This system can be used with low-cost PC hardware and consumer-level 3D displays for tele-medical surgical applications including military medical support, disaster relief, and space exploration. PMID:22356964

  2. Interactive Digital Technologies' Use in Southwest Nigerian Universities

    ERIC Educational Resources Information Center

    Agbatogun, Alaba Olaoluwakotansibe

    2013-01-01

    The interactive digital technologies in education is an effective means used to widen educational opportunities. However, many faculty members do not use or adopt digital technologies as instructional tools. The purpose of this study was to predict faculty members' use of digital technologies in Nigerian Universities. 492 university lecturers from…

  3. Color segmentation as an aid to white balancing for digital still cameras

    NASA Astrophysics Data System (ADS)

    Cooper, Ted J.

    2000-12-01

    Digital Still Cameras employ automatic white balance techniques to adjust sensor amplifier gains so that white imaged objects appear white. A color cast detection algorithm is presented that uses histogram and segmentation techniques to select near-neutral objects in the image. Once identified and classified, these objects permit determination of the scene illuminant and implicitly the respective amplifier gains. Under certain circumstances, a scene may contain no near-neutral objects. By using the segmentation operations on non-neutral image objects, memory colors, from skin, sky, and foliage objects, may be identified. If identified, these memory colors provide enough chromatic information to predict the scene illuminant. By combining the approaches from near-neutral objects with those of memory color objects, a reasonable automatic white balance over a wide range of scenes is possible.

  4. Noctilucent clouds: modern ground-based photographic observations by a digital camera network.

    PubMed

    Dubietis, Audrius; Dalin, Peter; Balčiūnas, Ričardas; Černis, Kazimieras; Pertsev, Nikolay; Sukhodoev, Vladimir; Perminov, Vladimir; Zalcik, Mark; Zadorozhny, Alexander; Connors, Martin; Schofield, Ian; McEwan, Tom; McEachran, Iain; Frandsen, Soeren; Hansen, Ole; Andersen, Holger; Grønne, Jesper; Melnikov, Dmitry; Manevich, Alexander; Romejko, Vitaly

    2011-10-01

    Noctilucent, or "night-shining," clouds (NLCs) are a spectacular optical nighttime phenomenon that is very often neglected in the context of atmospheric optics. This paper gives a brief overview of current understanding of NLCs by providing a simple physical picture of their formation, relevant observational characteristics, and scientific challenges of NLC research. Modern ground-based photographic NLC observations, carried out in the framework of automated digital camera networks around the globe, are outlined. In particular, the obtained results refer to studies of single quasi-stationary waves in the NLC field. These waves exhibit specific propagation properties--high localization, robustness, and long lifetime--that are the essential requisites of solitary waves. PMID:22016249

  5. Colorimetric characterization of digital cameras with unrestricted capture settings applicable for different illumination circumstances

    NASA Astrophysics Data System (ADS)

    Fang, Jingyu; Xu, Haisong; Wang, Zhehong; Wu, Xiaomin

    2016-05-01

    With colorimetric characterization, digital cameras can be used as image-based tristimulus colorimeters for color communication. In order to overcome the restriction of fixed capture settings adopted in the conventional colorimetric characterization procedures, a novel method was proposed considering capture settings. The method calculating colorimetric value of the measured image contains five main steps, including conversion from RGB values to equivalent ones of training settings through factors based on imaging system model so as to build the bridge between different settings, scaling factors involved in preparation steps for transformation mapping to avoid errors resulted from nonlinearity of polynomial mapping for different ranges of illumination levels. The experiment results indicate that the prediction error of the proposed method, which was measured by CIELAB color difference formula, reaches less than 2 CIELAB units under different illumination levels and different correlated color temperatures. This prediction accuracy for different capture settings remains the same level as the conventional method for particular lighting condition.

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

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

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

  7. Estimating information from image colors: an application to digital cameras and natural scenes.

    PubMed

    Marín-Franch, Iván; Foster, David H

    2013-01-01

    The colors present in an image of a scene provide information about its constituent elements. But the amount of information depends on the imaging conditions and on how information is calculated. This work had two aims. The first was to derive explicitly estimators of the information available and the information retrieved from the color values at each point in images of a scene under different illuminations. The second was to apply these estimators to simulations of images obtained with five sets of sensors used in digital cameras and with the cone photoreceptors of the human eye. Estimates were obtained for 50 hyperspectral images of natural scenes under daylight illuminants with correlated color temperatures 4,000, 6,500, and 25,000 K. Depending on the sensor set, the mean estimated information available across images with the largest illumination difference varied from 15.5 to 18.0 bits and the mean estimated information retrieved after optimal linear processing varied from 13.2 to 15.5 bits (each about 85 percent of the corresponding information available). With the best sensor set, 390 percent more points could be identified per scene than with the worst. Capturing scene information from image colors depends crucially on the choice of camera sensors. PMID:22450817

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

    NASA Astrophysics Data System (ADS)

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

    2001-07-01

    Skin hydration is a key factor in skin health. Hydration measurements can provide diagnostic information on the condition of skin and can indicate the integrity of the skin barrier function. Near-infrared spectroscopy measures the water content of living tissue by its effect on tissue reflectance at a particular wavelength. Imaging has the important advantage of showing the degree of hydration as a function of location. Short-wavelength (650-1050 nm) near infrared spectroscopic reflectance imaging has previously been used in-vivo to determine the relative water content of skin under carefully controlled laboratory conditions. We have recently developed a novel spectroscopic imaging system to acquire image sets in the long-wavelength region of the near infrared (960 to 1700 nm), where the water absorption bands are more intense. The LW-NIR systems uses a liquid- crystal tunable filter in front of the objective lens and incorporates a 12-bit digital camera with a 320-by-240-pixel indium-gallium arsenide array sensor. Custom software controls the camera and tunable filter, allowing image sets to be acquired and displayed in near-real time. Forearm skin hydration was measured in a clinical context using the long- wavelength imaging system, a short-wavelength imaging system, and non-imaging instrumentation. Among these, the LW-NIR system appears to be the most sensitive at measuring dehydration of skin.

  9. Evaluation of the geometric stability and the accuracy potential of digital cameras — Comparing mechanical stabilisation versus parameterisation

    NASA Astrophysics Data System (ADS)

    Rieke-Zapp, D.; Tecklenburg, W.; Peipe, J.; Hastedt, H.; Haig, Claudia

    Recent tests on the geometric stability of several digital cameras that were not designed for photogrammetric applications have shown that the accomplished accuracies in object space are either limited or that the accuracy potential is not exploited to the fullest extent. A total of 72 calibrations were calculated with four different software products for eleven digital camera models with different hardware setups, some with mechanical fixation of one or more parts. The calibration procedure was chosen in accord to a German guideline for evaluation of optical 3D measuring systems [VDI/VDE, VDI/VDE 2634 Part 1, 2002. Optical 3D Measuring Systems-Imaging Systems with Point-by-point Probing. Beuth Verlag, Berlin]. All images were taken with ringflashes which was considered a standard method for close-range photogrammetry. In cases where the flash was mounted to the lens, the force exerted on the lens tube and the camera mount greatly reduced the accomplished accuracy. Mounting the ringflash to the camera instead resulted in a large improvement of accuracy in object space. For standard calibration best accuracies in object space were accomplished with a Canon EOS 5D and a 35 mm Canon lens where the focusing tube was fixed with epoxy (47 μm maximum absolute length measurement error in object space). The fixation of the Canon lens was fairly easy and inexpensive resulting in a sevenfold increase in accuracy compared with the same lens type without modification. A similar accuracy was accomplished with a Nikon D3 when mounting the ringflash to the camera instead of the lens (52 μm maximum absolute length measurement error in object space). Parameterisation of geometric instabilities by introduction of an image variant interior orientation in the calibration process improved results for most cameras. In this case, a modified Alpa 12 WA yielded the best results (29 μm maximum absolute length measurement error in object space). Extending the parameter model with Fi

  10. Calibration of Low Cost Digital Camera Using Data from Simultaneous LIDAR and Photogrammetric Surveys

    NASA Astrophysics Data System (ADS)

    Mitishita, E.; Debiasi, P.; Hainosz, F.; Centeno, J.

    2012-07-01

    Digital photogrammetric products from the integration of imagery and lidar datasets are a reality nowadays. When the imagery and lidar surveys are performed together and the camera is connected to the lidar system, a direct georeferencing can be applied to compute the exterior orientation parameters of the images. Direct georeferencing of the images requires accurate interior orientation parameters to perform photogrammetric application. Camera calibration is a procedure applied to compute the interior orientation parameters (IOPs). Calibration researches have established that to obtain accurate IOPs, the calibration must be performed with same or equal condition that the photogrammetric survey is done. This paper shows the methodology and experiments results from in situ self-calibration using a simultaneous images block and lidar dataset. The calibration results are analyzed and discussed. To perform this research a test field was fixed in an urban area. A set of signalized points was implanted on the test field to use as the check points or control points. The photogrammetric images and lidar dataset of the test field were taken simultaneously. Four strips of flight were used to obtain a cross layout. The strips were taken with opposite directions of flight (W-E, E-W, N-S and S-N). The Kodak DSC Pro SLR/c digital camera was connected to the lidar system. The coordinates of the exposition station were computed from the lidar trajectory. Different layouts of vertical control points were used in the calibration experiments. The experiments use vertical coordinates from precise differential GPS survey or computed by an interpolation procedure using the lidar dataset. The positions of the exposition stations are used as control points in the calibration procedure to eliminate the linear dependency of the group of interior and exterior orientation parameters. This linear dependency happens, in the calibration procedure, when the vertical images and flat test field are

  11. Real-time increase in depth of field of an uncooled thermal camera using several phase-mask technologies.

    PubMed

    Diaz, Frédéric; Lee, Mane-Si Laure; Rejeaunier, Xavier; Lehoucq, Gaelle; Goudail, François; Loiseaux, Brigitte; Bansropun, Shailendra; Rollin, Joel; Debes, Eric; Mils, Philippe

    2011-02-01

    Imaging systems that combine a phase mask in the pupil and digital postprocessing may have better performance than conventional ones. We have built such a system to enhance the depth of field of an uncooled thermal camera. The phase masks are binary, their structures are optimized thanks to an image quality criterion, and they have been realized with three different technologies that give equivalent results. The deconvolution postprocessing is performed in real time with a graphics processing unit. A significant increase of the depth of field of a factor 3 has been obtained. PMID:21283209

  12. Counterfeit deterrence and digital imaging technology

    NASA Astrophysics Data System (ADS)

    Church, Sara E.; Fuller, Reese H.; Jaffe, Annette B.; Pagano, Lorelei W.

    2000-04-01

    The US government recognizes the growing problem of counterfeiting currency using digital imaging technology, as desktop systems become more sophisticated, less expensive and more prevalent. As the rate of counterfeiting with this type of equipment has grown, the need for specific prevention methods has become apparent to the banknote authorities. As a result, the Treasury Department and Federal Reserve have begun to address issues related specifically to this type of counterfeiting. The technical representatives of these agencies are taking a comprehensive approach to minimize counterfeiting using digital technology. This approach includes identification of current technology solutions for banknote recognition, data stream intervention and output marking, outreach to the hardware and software industries and enhancement of public education efforts. Other aspects include strong support and cooperation with existing international efforts to prevent counterfeiting, review and amendment of existing anti- counterfeiting legislation and investigation of currency design techniques to make faithful reproduction more difficult. Implementation of these steps and others are to lead to establishment of a formal, permanent policy to address and prevent the use of emerging technologies to counterfeit currency.

  13. Quality Metrics of Semi Automatic DTM from Large Format Digital Camera

    NASA Astrophysics Data System (ADS)

    Narendran, J.; Srinivas, P.; Udayalakshmi, M.; Muralikrishnan, S.

    2014-11-01

    The high resolution digital images from Ultracam-D Large Format Digital Camera (LFDC) was used for near automatic DTM generation. In the past, manual method for DTM generation was used which are time consuming and labour intensive. In this study LFDC in synergy with accurate position and orientation system and processes like image matching algorithms, distributed processing and filtering techniques for near automatic DTM generation. Traditionally the DTM accuracy is reported using check points collected from the field which are limited in number, time consuming and costly. This paper discusses the reliability of near automatic DTM generated from Ultracam-D for an operational project covering an area of nearly 600 Sq. Km. using 21,000 check points captured stereoscopically by experienced operators. The reliability of the DTM for the three study areas with different morphology is presented using large number of stereo check points and parameters related to statistical distribution of residuals such as skewness, kurtosis, standard deviation and linear error at 90% confidence interval. The residuals obtained for the three areas follow normal distribution in agreement with the majority of standards on positional accuracy. The quality metrics in terms of reliability were computed for the DTMs generated and the tables and graphs show the potential of Ultracam-D for the generation of semiautomatic DTM process for different terrain types.

  14. Differentiating Digital Writing Instruction: The Intersection of Technology, Writing Instruction, and Digital Genre Knowledge

    ERIC Educational Resources Information Center

    Martin, Nicole M.; Lambert, Claire

    2015-01-01

    U.S. adolescents' prior technology experiences and exposure to digital genres vary, but they will often write digital texts as they enter college and adulthood. We explored middle school students' digital writing instructional experience in the context of a university-based summer digital writing camp. The sixth- through eighth-grade adolescents…

  15. A practical enhanced-resolution integrated optical-digital imaging camera (PERIODIC)

    NASA Astrophysics Data System (ADS)

    Mirotznik, M.; Mathews, S.; Plemmons, R.; Pauca, P.; Torgersen, T.; Barnard, R.; Gray, B.; Zhang, Q.; van der Gracht, J.; Curt, P.; Bodnar, M.; Prasad, S.

    2009-05-01

    An integrated array computational imaging system, dubbed PERIODIC, is presented which is capable of exploiting a diverse variety of optical information including sub-pixel displacements, phase, polarization, intensity, and wavelength. Several applications of this technology will be presented including digital superresolution, enhanced dynamic range and multi-spectral imaging. Other applications include polarization based dehazing, extended depth of field and 3D imaging. The optical hardware system and software algorithms are described, and sample results are shown.

  16. Field test of an autocorrelation technique for determining grain size using a digital camera

    NASA Astrophysics Data System (ADS)

    Barnard, P. L.; Rubin, D. M.; Harney, J.; Mustain, N.

    2007-12-01

    An extensive field test using Rubin's (2004) autocorrelation technique shows that median and mean grain size can be determined with suitable accuracy using a digital camera and associated autocorrelation when compared to traditional methods such as mechanical sieving and settling-tube analysis. The field test included 205 sediment samples and > 1200 digital images from a variety of beaches on the west coast of the United States, with grain sizes ranging from sand to granules. To test the accuracy of the digital-image grain-size algorithm, we compared results with manual point counts of a large image data set in the Santa Barbara littoral cell. Grain sizes calculated using the autocorrelation algorithm were highly correlated with the point counts of the same images (r2=0.93; n=79) and had an error of only 1%. Although grain sizes calculated from digital images give an accurate result for grains in the image, natural lateral and vertical variability in grain size can cause differences between grain size measured in digital images of the bed surface and grain size measured by sieving a grab sample that includes subsurface sediment. Lateral spatial variability was tested by analyzing the results of up to 100 images taken in a series of 1 m2 sample areas. Comparisons of calculated grain sizes and grain sizes measured from grab samples show small differences between surface sediment and grab samples on high- energy dissipative beaches with well-sorted sediment such as in the Pacific Northwest (r2 > 0.92; n=115). In contrast, on less dissipative, more poorly sorted beaches such as Ocean Beach in San Francisco, differences between surface and subsurface grain size are greater (r2 > 0.70; n=67; within 3% accuracy). In all field tests the autocorrelation method was able to predict the mean and median grain size with ~96% accuracy, which is more than adequate for the majority of sedimentological applications. When properly automated for large numbers of samples, the

  17. Deconstructing Digital Natives: Young People, Technology, and the New Literacies

    ERIC Educational Resources Information Center

    Thomas, Michael, Ed.

    2011-01-01

    There have been many attempts to define the generation of students who emerged with the Web and new digital technologies in the early 1990s. The term "digital native" refers to the generation born after 1980, which has grown up in a world where digital technologies and the internet are a normal part of everyday life. Young people belonging to this…

  18. New Stereo Vision Digital Camera System for Simultaneous Measurement of Cloud Base Height and Atmospheric Visibility

    NASA Astrophysics Data System (ADS)

    Janeiro, F. M.; Carretas, F.; Palma, N.; Ramos, P. M.; Wagner, F.

    2013-12-01

    Clouds play an important role in many aspects of everyday life. They affect both the local weather as well as the global climate and are an important parameter on climate change studies. Cloud parameters are also important for weather prediction models which make use of actual measurements. It is thus important to have low-cost instrumentation that can be deployed in the field to measure those parameters. This kind of instruments should also be automated and robust since they may be deployed in remote places and be subject to adverse weather conditions. Although clouds are very important in environmental systems, they are also an essential component of airplane safety when visual flight rules (VFR) are enforced, such as in most small aerodromes where it is not economically viable to install instruments for assisted flying. Under VFR there are strict limits on the height of the cloud base, cloud cover and atmospheric visibility that ensure the safety of the pilots and planes. Although there are instruments, available in the market, to measure those parameters, their relatively high cost makes them unavailable in many local aerodromes. In this work we present a new prototype which has been recently developed and deployed in a local aerodrome as proof of concept. It is composed by two digital cameras that capture photographs of the sky and allow the measurement of the cloud height from the parallax effect. The new developments consist on having a new geometry which allows the simultaneous measurement of cloud base height, wind speed at cloud base height and atmospheric visibility, which was not previously possible with only two cameras. The new orientation of the cameras comes at the cost of a more complex geometry to measure the cloud base height. The atmospheric visibility is calculated from the Lambert-Beer law after the measurement of the contrast between a set of dark objects and the background sky. The prototype includes the latest hardware developments that

  19. The use of a consumer grade photo camera in optical-digital correlator for pattern recognition and input scene restoration

    NASA Astrophysics Data System (ADS)

    Konnik, Mikhail V.; Starikov, Sergey N.

    2009-11-01

    In this work an optical-digital correlator for pattern recognition and input scene restoration is described. Main features of the described correlator are portability and ability of multi-element input scenes processing. The correlator consists of a consumer grade digital photo camera with a diffractive optical element (DOE) inserted as a correlation filter. Correlation of an input scene with a reference image recorded on the DOE are provided optically and registered by the digital photo camera for further processing. Using obtained correlation signals and DOE's point spread function (PSF), one can restore the image of the input scene from the image of correlation signals by digital deconvolution algorithms. The construction of the correlator based on the consumer grade digital photo camera is presented. The software procedure that is necessary for images linearization of correlation signals is described. Experimental results on optical correlation are compared with numerical simulation. The results of images restoration from conventionally and specially processed correlation signals are reported. Quantitative estimations of accuracy of correlation signals as well as restored images of the input scene are presented.

  20. Using digital time-lapse cameras to monitor species-specific understorey and overstorey phenology in support of wildlife habitat assessment.

    PubMed

    Bater, Christopher W; Coops, Nicholas C; Wulder, Michael A; Hilker, Thomas; Nielsen, Scott E; McDermid, Greg; Stenhouse, Gordon B

    2011-09-01

    Critical to habitat management is the understanding of not only the location of animal food resources, but also the timing of their availability. Grizzly bear (Ursus arctos) diets, for example, shift seasonally as different vegetation species enter key phenological phases. In this paper, we describe the use of a network of seven ground-based digital camera systems to monitor understorey and overstorey vegetation within species-specific regions of interest. Established across an elevation gradient in western Alberta, Canada, the cameras collected true-colour (RGB) images daily from 13 April 2009 to 27 October 2009. Fourth-order polynomials were fit to an RGB-derived index, which was then compared to field-based observations of phenological phases. Using linear regression to statistically relate the camera and field data, results indicated that 61% (r (2) = 0.61, df = 1, F = 14.3, p = 0.0043) of the variance observed in the field phenological phase data is captured by the cameras for the start of the growing season and 72% (r (2) = 0.72, df = 1, F = 23.09, p = 0.0009) of the variance in length of growing season. Based on the linear regression models, the mean absolute differences in residuals between predicted and observed start of growing season and length of growing season were 4 and 6 days, respectively. This work extends upon previous research by demonstrating that specific understorey and overstorey species can be targeted for phenological monitoring in a forested environment, using readily available digital camera technology and RGB-based vegetation indices. PMID:21082343

  1. Teaching "Digital Earth" technologies in Environmental Sciences

    NASA Astrophysics Data System (ADS)

    Griffiths, J. A.

    2014-04-01

    As part of a review process for a module entitled "Digital Earth" which is currently taught as part of a BSc in Environmental Sciences program, research into the current provision of Geographical Information Science and Technology (GIS&T) related modules on UKbased Environmental Science degrees is made. The result of this search is used with DiBiase et al. (2006) "Body of Knowledge of GIS&T" to develop a foundation level module for Environmental Sciences. Reference is also made to the current provision geospatial analysis techniques in secondary and tertiary education in the UK, US and China, and the optimal use of IT and multimedia in geo-education.

  2. On digital image processing technology and application in geometric measure

    NASA Astrophysics Data System (ADS)

    Yuan, Jiugen; Xing, Ruonan; Liao, Na

    2014-04-01

    Digital image processing technique is an emerging science that emerging with the development of semiconductor integrated circuit technology and computer science technology since the 1960s.The article introduces the digital image processing technique and principle during measuring compared with the traditional optical measurement method. It takes geometric measure as an example and introduced the development tendency of digital image processing technology from the perspective of technology application.

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

  4. Today's CAD/CAM: flexible digital technologies expanding workflow options.

    PubMed

    Ferencz, Jonathan L

    2015-03-01

    CAD/CAM and digital scanning technologies have become essential components of dentistry. Digital impression scanning, restoration design, and manufacturing techniques yield greater treatment predictability, high-level esthetics, and functional accuracy using a variety of materials. PMID:25822749

  5. New Integrated Video and Graphics Technology: Digital Video Interactive.

    ERIC Educational Resources Information Center

    Optical Information Systems, 1987

    1987-01-01

    Describes digital video interactive (DVI), a new technology which combines the interactivity of the graphics capabilities in personal computers with the realism of high-quality motion video and multitrack audio in an all-digital integrated system. (MES)

  6. A Historical Perspective on Digital Hearing Aids: How Digital Technology Has Changed Modern Hearing Aids

    PubMed Central

    Levitt, Harry

    2007-01-01

    This article provides the author's perspective on the development of digital hearing aids and how digital signal processing approaches have led to changes in hearing aid design. Major landmarks in the evolution of digital technology are identified, and their impact on the development of digital hearing aids is discussed. Differences between analog and digital approaches to signal processing in hearing aids are identified. PMID:17301334

  7. Respiratory-Gated MRgHIFU in Upper Abdomen Using an MR-Compatible In-Bore Digital Camera

    PubMed Central

    Petrusca, Lorena; Viallon, Magalie; Muller, Arnaud; Breguet, Romain; Becker, Christoph D.; Salomir, Rares

    2014-01-01

    Objective. To demonstrate the technical feasibility and the potential interest of using a digital optical camera inside the MR magnet bore for monitoring the breathing cycle and subsequently gating the PRFS MR thermometry, MR-ARFI measurement, and MRgHIFU sonication in the upper abdomen. Materials and Methods. A digital camera was reengineered to remove its magnetic parts and was further equipped with a 7 m long USB cable. The system was electromagnetically shielded and operated inside the bore of a closed 3T clinical scanner. Suitable triggers were generated based on real-time motion analysis of the images produced by the camera (resolution 640 × 480 pixels, 30 fps). Respiratory-gated MR-ARFI prepared MRgHIFU ablation was performed in the kidney and liver of two sheep in vivo, under general anaesthesia and ventilator-driven forced breathing. Results. The optical device demonstrated very good MR compatibility. The current setup permitted the acquisition of motion artefact-free and high resolution MR 2D ARFI and multiplanar interleaved PRFS thermometry (average SNR 30 in liver and 56 in kidney). Microscopic histology indicated precise focal lesions with sharply delineated margins following the respiratory-gated HIFU sonications. Conclusion. The proof-of-concept for respiratory motion management in MRgHIFU using an in-bore digital camera has been validated in vivo. PMID:24716196

  8. The integration of digital camera derived images with a computer based diabetes register for use in retinal screening.

    PubMed

    Taylor, D J; Jacob, J S; Tooke, J E

    2000-07-01

    Exeter district provides a retinal screening service based on a mobile non-mydriatic camera operated by a dedicated retinal screener visiting general practices on a 2-yearly cycle. Digital attachments to eye cameras can now provide a cost effective alternative to the use of film in population based eye screening programmes. Whilst the manufacturers of digital cameras provide a database for the storage of pictures, the images do not as yet interface readily with the rest of the patient's computer held data or allow for a sophisticated grading, reporting and administration system. The system described is a development of the Exeter diabetes register (EXSYST) which can import digitally derived pictures from either Ris-Lite TM and Imagenet TM camera systems or scanned Polaroids Pictures can be reported by the screener, checked by a consultant ophthalmologist via the hospital network, and a report, consisting of colour pictures, map of relevant pathology and referral recommendations produced. This concise report can be hard copied inexpensively on a high resolution ink-jet printer to be returned to the patient's general practitioner. Eye images remain available within the hospital diabetes centre computer network to facilitate shared care. This integrated system would form an ideal platform for the addition of computer based pathology recognition and total paperless transmission when suitable links to GP surgeries become available. PMID:10837903

  9. Digital Technology for Geological Field Mapping

    NASA Astrophysics Data System (ADS)

    Rourke, Peter; Smith, Stuart; Vaughan, Alan; Ellis, Jenny

    2014-05-01

    The amount of time that students and professionals spend in the field has reduced over the past 25 years (Gibbs, 2012). Recent advances in technology are changing the way students and professionals are able to conduct geological field study. Applications such as Midland Valley Exploration's FieldMove Clino now allow the geologist to use their smartphone as a fast, georeferenced measuring device compared with a traditional compass-clinometer. Although we support the view that an understanding of field mapping and model building, taught at university level, is essential to give the geologist the ability to think in three and four dimensions, new technologies that automate the ability to digitise and visualise data in the field lead to a better appreciation of the geometry, scale, and evolution of geological structures and trapping mechanisms that will be encountered during a career in industry. The majority of future industry professionals own a smartphone or tablet device: A recent study found that four-fifths of new students own a smartphone and one-fifth own a tablet device (UCAS Media, 2013). This figure is increasing with each new intake of geoscience students. With the increased availability and affordability of smartphone and tablet devices, new techniques are being examined for digital data collection in the field. If the trend continues that geoscience students are likely to spend less time in the field than their predecessors, then the time available must be spent as effectively as possible. Digital devices allow students and professionals alike to optimise the time spent in the field, allowing more time to think about geological relationships, and highlighting areas of uncertainty that can be studied further. This poster will examine the use of new digital smartphone and tablet devices for the collection of geological field data.

  10. Implementing PET-guided biopsy: integrating functional imaging data with digital x-ray mammography cameras

    NASA Astrophysics Data System (ADS)

    Weinberg, Irving N.; Zawarzin, Valera; Pani, Roberto; Williams, Rodney C.; Freimanis, Rita L.; Lesko, Nadia M.; Levine, E. A.; Perrier, N.; Berg, Wendie A.; Adler, Lee P.

    2001-05-01

    Purpose: Phantom trials using the PET data for localization of hot spots have demonstrated positional accuracies in the millimeter range. We wanted to perform biopsy based on information from both anatomic and functional imaging modalities, however we had a communication challenge. Despite the digital nature of DSM stereotactic X-ray mammography devices, and the large number of such devices in Radiology Departments (approximately 1600 in the US alone), we are not aware of any methods of connecting stereo units to other computers in the Radiology department. Methods: We implemented a local network between an external IBM PC (running Linux) and the Lorad Stereotactic Digital Spot Mammography PC (running DOS). The application used IP protocol on the parallel port, and could be run in the background on the LORAD PC without disrupting important clinical activities such as image acquisition or archiving. With this software application, users of the external PC could pull x-ray images on demand form the Load DSM computer. Results: X-ray images took about a minute to ship to the external PC for analysis or forwarding to other computers on the University's network. Using image fusion techniques we were able to designate locations of functional imaging features as the additional targets on the anatomic x-rays. These pseudo-features could then potentially be used to guide biopsy using the stereotactic gun stage on the Lorad camera. New Work to be Presented: A method of transferring and processing stereotactic x-ray mammography images to a functional PET workstation for implementing image-guided biopsy.

  11. Seismic Rayleigh Wave Digital Processing Technology

    NASA Astrophysics Data System (ADS)

    Jie, Li

    2013-04-01

    In Rayleigh wave exploration, the digital processing of data plays a very important position. This directly affects the interpretation of ground effect. Therefore, the use of accurate processing software and effective method in the Rayleigh wave exploration has important theoretical and practical significance. Previously, Rayleigh wave dispersion curve obtained by the one-dimensional phase analysis. This method requires channel spacing should be less than the effective wavelength. And minimal phase error will cause great changes in the phase velocity of Rayleigh wave. Damped least square method is a local linear model. It is easy to cause that inversion objective function cannot find the global optimal solution. Therefore, the method and the technology used in the past are difficult to apply the requirements of the current Rayleigh wave exploration. This study focused on the related technologies and algorithms of F-K domain dispersion curve extraction and GA global non-linear inversion, and combined with the impact of Rayleigh wave data acquisition parameters and the characteristics. Rayleigh wave exploration data processing software design and process technology research is completed. Firstly, the article describes the theoretical basis of Rayleigh wave method. This is also part of the theoretical basis of following treatment. The theoretical proof of existence of Rayleigh wave Dispersive in layered strata. Secondly, F-K domain dispersion curve extraction tests showed that the method can overcome the one-dimensional digital processing technology deficiencies, and make full use of multi-channel Rayleigh wave data record information. GA global non-linear inversion indicated that the inversion is not easy getting into local optimal solution. Thirdly, some examples illustrate each mode Rayleigh wave dispersion curve characteristics in the X-T domain. Tests demonstrated the impact on their extraction of dispersion curves. Parameters change example (including the X

  12. The Impact of Digital Technologies on the Elementary School Classroom.

    ERIC Educational Resources Information Center

    Ruberg, Laurie; And Others

    This paper examines the impact of digital technologies on an elementary school classroom. The following topics are addressed: (1) how classrooms were physically adjusted to incorporate new digital technologies; (2) the context and content areas in which students used these technologies, based on observation, teacher interviews, and teacher…

  13. Applying Digital Sensor Technology: A Problem-Solving Approach

    ERIC Educational Resources Information Center

    Seedhouse, Paul; Knight, Dawn

    2016-01-01

    There is currently an explosion in the number and range of new devices coming onto the technology market that use digital sensor technology to track aspects of human behaviour. In this article, we present and exemplify a three-stage model for the application of digital sensor technology in applied linguistics that we have developed, namely,…

  14. Commercial communications technology on the digital battlefield

    NASA Astrophysics Data System (ADS)

    Kalomiris, Vasilios E.; Hafer, Tom

    1996-06-01

    To meet its objectives of winning the information ware and digitizing the battlefield, the U.S. Army must leverage advances in commercial technology. The Department of Defense has adopted a new approach to acquiring and fielding systems in response to economic realities and the need to incorporate rapidly advancing commercial technology into Army systems. This approach calls for the evaluation of commercial breakthroughs in a laboratory environment followed by evaluation by the user in a warfighting experiment. The most promising products are then transitioned to a program executive officer/project manager for accelerated acquisition and fielding. The U.S. Army Communications-Electronics Command (CECOM) Research, Development and Engineering Center Space & Terrestrial Communications Directorate is working with the Advanced Research Projects Agency (ARPA) to study the applicability of personal communications systems and related technologies for Army applications. The results of this cooperative effort were demonstrated in 1995 through the use of the trunked Land Mobile Radio (LMR) during field exercises. This paper will describe the joint CECOM/ARPA programs that sponsor the evaluation of commercial technologies, characteristics of the LMR and the details of its interface with the legacy systems, and current plans for further experimentation/evaluation.

  15. Digital chemiluminescence imaging of DNA sequencing blots using a charge-coupled device camera.

    PubMed Central

    Karger, A E; Weiss, R; Gesteland, R F

    1992-01-01

    Digital chemiluminescence imaging with a cryogenically cooled charge-coupled device (CCD) camera is used to visualize DNA sequencing fragments covalently bound to a blotting membrane. The detection is based on DNA hybridization with an alkaline phosphatase(AP) labeled oligodeoxyribonucleotide probe and AP triggered chemiluminescence of the substrate 3-(2'-spiro-adamantane)-4-methoxy-4-(3"-phosphoryloxy)phenyl- 1,2-dioxetane (AMPPD). The detection using a direct AP-oligonucleotide conjugate is compared to the secondary detection of biotinylated oligonucleotides with respect to their sensitivity and nonspecific binding to the nylon membrane by quantitative imaging. Using the direct oligonucleotide-AP conjugate as a hybridization probe, sub-attomol (0.5 pg of 2.7 kb pUC plasmid DNA) quantities of membrane bound DNA are detectable with 30 min CCD exposures. Detection using the biotinylated probe in combination with streptavidin-AP was found to be background limited by nonspecific binding of streptavidin-AP and the oligo(biotin-11-dUTP) label in equal proportions. In contrast, the nonspecific background of AP-labeled oligonucleotide is indistinguishable from that seen with 5'-32P-label, in that respect making AP an ideal enzymatic label. The effect of hybridization time, probe concentration, and presence of luminescence enhancers on the detection of plasmid DNA were investigated. Images PMID:1480487

  16. New long-zoom lens for 4K super 35mm digital cameras

    NASA Astrophysics Data System (ADS)

    Thorpe, Laurence J.; Usui, Fumiaki; Kamata, Ryuhei

    2015-05-01

    The world of television production is beginning to adopt 4K Super 35 mm (S35) image capture for a widening range of program genres that seek both the unique imaging properties of that large image format and the protection of their program assets in a world anticipating future 4K services. Documentary and natural history production in particular are transitioning to this form of production. The nature of their shooting demands long zoom lenses. In their traditional world of 2/3-inch digital HDTV cameras they have a broad choice in portable lenses - with zoom ranges as high as 40:1. In the world of Super 35mm the longest zoom lens is limited to 12:1 offering a telephoto of 400mm. Canon was requested to consider a significantly longer focal range lens while severely curtailing its size and weight. Extensive computer simulation explored countless combinations of optical and optomechanical systems in a quest to ensure that all operational requests and full 4K performance could be met. The final lens design is anticipated to have applications beyond entertainment production, including a variety of security systems.

  17. Measuring the orbital period of the Moon using a digital camera

    NASA Astrophysics Data System (ADS)

    Hughes, Stephen W.

    2006-03-01

    A method of measuring the orbital velocity of the Moon around the Earth using a digital camera is described. Separate images of the Moon and stars taken 24 hours apart were loaded into Microsoft PowerPoint and the centre of the Moon marked on each image. Four stars common to both images were connected together to form a 'home-made' constellation. On each image the Moon and constellation were grouped together. The group from one image was pasted onto the other image and translated and rotated so that the two constellations overlay each other. The distance between the Moon centres in pixels was converted into a physical distance on the CCD chip in order to calculate the angular separation on the sky. The angular movement was then used to calculate the orbital period of the Moon. A metre rule was photographed from a known distance in order to calculate the physical size of the CCD pixels. The orbital period of the Moon was measured as 27.1 days, which is within 0.7% of the actual period of 27.3 days.

  18. A new lunar digital elevation model from the Lunar Orbiter Laser Altimeter and SELENE Terrain Camera

    NASA Astrophysics Data System (ADS)

    Barker, M. K.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Haruyama, J.; Smith, D. E.

    2016-07-01

    We present an improved lunar digital elevation model (DEM) covering latitudes within ±60°, at a horizontal resolution of 512 pixels per degree (∼60 m at the equator) and a typical vertical accuracy ∼3 to 4 m. This DEM is constructed from ∼ 4.5 ×109 geodetically-accurate topographic heights from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter, to which we co-registered 43,200 stereo-derived DEMs (each 1° × 1°) from the SELENE Terrain Camera (TC) (∼1010 pixels total). After co-registration, approximately 90% of the TC DEMs show root-mean-square vertical residuals with the LOLA data of <5 m compared to ∼ 50% prior to co-registration. We use the co-registered TC data to estimate and correct orbital and pointing geolocation errors from the LOLA altimetric profiles (typically amounting to <10 m horizontally and <1 m vertically). By combining both co-registered datasets, we obtain a near-global DEM with high geodetic accuracy, and without the need for surface interpolation. We evaluate the resulting LOLA + TC merged DEM (designated as "SLDEM2015") with particular attention to quantifying seams and crossover errors.

  19. Tone-transfer (OECF) characteristics and spatial frequency response measurements for digital cameras and scanners

    NASA Astrophysics Data System (ADS)

    Burns, Peter D.

    2005-01-01

    Measurement of the spatial frequency response (SFR) of digital still cameras by slanted-edge analysis has been established for several years. The method, described in standard ISO 12233, has also been applied to other image acquisition subsystems such as document and print scanners. With the frequent application of the method and use of supporting software, questions often arise about the form of the input test image data. The tone-transfer characteristics of the system under test can influence the results, as can signal quantization and clipping. For this reason, the original standard called for a transformation of the input data prior to the slanted-edge analysis. The transformation is based on the measured opto-electronic conversion function (OECF) and can convert the image data to a reference-exposure signal space. This is often helpful when comparing different devices, if the intent is to do so in terms of the performance of optics, detector, and primary signal processing. We describe the use of the OECF and its inverse to derive the signal transformation in question. The influence of typical characteristics will be shown in several examples. It was found that, for test target data of modest contrast, the resulting SFR measurements were only moderately sensitive to the use of the inverse OECF transformation.

  20. Tone-transfer (OECF) characteristics and spatial frequency response measurements for digital cameras and scanners

    NASA Astrophysics Data System (ADS)

    Burns, Peter D.

    2004-10-01

    Measurement of the spatial frequency response (SFR) of digital still cameras by slanted-edge analysis has been established for several years. The method, described in standard ISO 12233, has also been applied to other image acquisition subsystems such as document and print scanners. With the frequent application of the method and use of supporting software, questions often arise about the form of the input test image data. The tone-transfer characteristics of the system under test can influence the results, as can signal quantization and clipping. For this reason, the original standard called for a transformation of the input data prior to the slanted-edge analysis. The transformation is based on the measured opto-electronic conversion function (OECF) and can convert the image data to a reference-exposure signal space. This is often helpful when comparing different devices, if the intent is to do so in terms of the performance of optics, detector, and primary signal processing. We describe the use of the OECF and its inverse to derive the signal transformation in question. The influence of typical characteristics will be shown in several examples. It was found that, for test target data of modest contrast, the resulting SFR measurements were only moderately sensitive to the use of the inverse OECF transformation.

  1. Transitioning towards the Digital Native: Examining Digital Technologies, Video Games, and Learning

    ERIC Educational Resources Information Center

    Salomon, John

    2010-01-01

    Although digital technologies have become commonplace among people who grew up around them, little is known about the effect that such technology will have on learners or its impact on traditional methods of educational delivery. This dissertation examines how certain technologies affect digital natives and seeks to understand specific…

  2. Study on key techniques for camera-based hydrological record image digitization

    NASA Astrophysics Data System (ADS)

    Li, Shijin; Zhan, Di; Hu, Jinlong; Gao, Xiangtao; Bo, Ping

    2015-10-01

    With the development of information technology, the digitization of scientific or engineering drawings has received more and more attention. In hydrology, meteorology, medicine and mining industry, the grid drawing sheet is commonly used to record the observations from sensors. However, these paper drawings may be destroyed and contaminated due to improper preservation or overuse. Further, it will be a heavy workload and prone to error if these data are manually transcripted into the computer. Hence, in order to digitize these drawings, establishing the corresponding data base will ensure the integrity of data and provide invaluable information for further research. This paper presents an automatic system for hydrological record image digitization, which consists of three key techniques, i.e., image segmentation, intersection point localization and distortion rectification. First, a novel approach to the binarization of the curves and grids in the water level sheet image has been proposed, which is based on the fusion of gradient and color information adaptively. Second, a fast search strategy for cross point location is invented and point-by-point processing is thus avoided, with the help of grid distribution information. And finally, we put forward a local rectification method through analyzing the central portions of the image and utilizing the domain knowledge of hydrology. The processing speed is accelerated, while the accuracy is still satisfying. Experiments on several real water level records show that our proposed techniques are effective and capable of recovering the hydrological observations accurately.

  3. Digital technology and human development: a charter for nature conservation.

    PubMed

    Maffey, Georgina; Homans, Hilary; Banks, Ken; Arts, Koen

    2015-11-01

    The application of digital technology in conservation holds much potential for advancing the understanding of, and facilitating interaction with, the natural world. In other sectors, digital technology has long been used to engage communities and share information. Human development-which holds parallels with the nature conservation sector-has seen a proliferation of innovation in technological development. Throughout this Perspective, we consider what nature conservation can learn from the introduction of digital technology in human development. From this, we derive a charter to be used before and throughout project development, in order to help reduce replication and failure of digital innovation in nature conservation projects. We argue that the proposed charter will promote collaboration with the development of digital tools and ensure that nature conservation projects progress appropriately with the development of new digital technologies. PMID:26508341

  4. Digital Technology Projects: Already Thriving in Public Libraries.

    ERIC Educational Resources Information Center

    Scally, Patricia H.

    1999-01-01

    Describes the results of a survey of public libraries that was conducted to identify digital technology projects. Highlights include kinds of collections being digitized (primarily photographs); costs; hardware and software used; experience levels of personnel; reasons for digitizing, including providing access to fragile materials; and technology…

  5. Dry imaging cameras

    PubMed Central

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

    2011-01-01

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

  6. Time-to-digital converter based on analog time expansion for 3D time-of-flight cameras

    NASA Astrophysics Data System (ADS)

    Tanveer, Muhammad; Nissinen, Ilkka; Nissinen, Jan; Kostamovaara, Juha; Borg, Johan; Johansson, Jonny

    2014-03-01

    This paper presents an architecture and achievable performance for a time-to-digital converter, for 3D time-of-flight cameras. This design is partitioned in two levels. In the first level, an analog time expansion, where the time interval to be measured is stretched by a factor k, is achieved by charging a capacitor with current I, followed by discharging the capacitor with a current I/k. In the second level, the final time to digital conversion is performed by a global gated ring oscillator based time-to-digital converter. The performance can be increased by exploiting its properties of intrinsic scrambling of quantization noise and mismatch error, and first order noise shaping. The stretched time interval is measured by counting full clock cycles and storing the states of nine phases of the gated ring oscillator. The frequency of the gated ring oscillator is approximately 131 MHz, and an appropriate stretch factor k, can give a resolution of ≍ 57 ps. The combined low nonlinearity of the time stretcher and the gated ring oscillator-based time-to-digital converter can achieve a distance resolution of a few centimeters with low power consumption and small area occupation. The carefully optimized circuit configuration achieved by using an edge aligner, the time amplification property and the gated ring oscillator-based time-to-digital converter may lead to a compact, low power single photon configuration for 3D time-of-flight cameras, aimed for a measurement range of 10 meters.

  7. Estimates of the error caused by atmospheric turbulence in determining object's motion speed using a digital camera

    NASA Astrophysics Data System (ADS)

    Valley, M. T.; Dudorov, V. V.; Kolosov, V. V.; Filimonov, G. A.

    2006-11-01

    The paper considers the error caused by atmospheric turbulence, in determining the motion speed of an object by using its successive images recorded on a matrix of a digital camera. Numerical modeling of the image of a moving object in successive time moments is performed. Fluctuation variance of the image mass centre affecting the measurement error is calculated. Error dependences on the distance to the object and path slope angle are obtained for different turbulence models. Considered are the situations, when the angular displacement of the object between two immediate shots of the digital camera is greater than the isoplanatism angle as well as the situations when the angular displacement is smaller than this angle.

  8. Two Years of Digital Terrain Model Production Using the Lunar Reconnaissance Orbiter Narrow Angle Camera

    NASA Astrophysics Data System (ADS)

    Burns, K.; Robinson, M. S.; Speyerer, E.; LROC Science Team

    2011-12-01

    One of the primary objectives of the Lunar Reconnaissance Orbiter Camera (LROC) is to gather stereo observations with the Narrow Angle Camera (NAC). These stereo observations are used to generate digital terrain models (DTMs). The NAC has a pixel scale of 0.5 to 2.0 meters but was not designed for stereo observations and thus requires the spacecraft to roll off-nadir to acquire these images. Slews interfere with the data collection of the other instruments, so opportunities are currently limited to four per day. Arizona State University has produced DTMs from 95 stereo pairs for 11 Constellation Project (CxP) sites (Aristarchus, Copernicus crater, Gruithuisen domes, Hortensius domes, Ina D-caldera, Lichtenberg crater, Mare Ingenii, Marius hills, Reiner Gamma, South Pole-Aitkin Rim, Sulpicius Gallus) as well as 30 other regions of scientific interest (including: Bhabha crater, highest and lowest elevation points, Highland Ponds, Kugler Anuchin, Linne Crater, Planck Crater, Slipher crater, Sears Crater, Mandel'shtam Crater, Virtanen Graben, Compton/Belkovich, Rumker Domes, King Crater, Luna 16/20/23/24 landing sites, Ranger 6 landing site, Wiener F Crater, Apollo 11/14/15/17, fresh craters, impact melt flows, Larmor Q crater, Mare Tranquillitatis pit, Hansteen Alpha, Moore F Crater, and Lassell Massif). To generate DTMs, the USGS ISIS software and SOCET SET° from BAE Systems are used. To increase the absolute accuracy of the DTMs, data obtained from the Lunar Orbiter Laser Altimeter (LOLA) is used to coregister the NAC images and define the geodetic reference frame. NAC DTMs have been used in examination of several sites, e.g. Compton-Belkovich, Marius Hills and Ina D-caldera [1-3]. LROC will continue to acquire high-resolution stereo images throughout the science phase of the mission and any extended mission opportunities, thus providing a vital dataset for scientific research as well as future human and robotic exploration. [1] B.L. Jolliff (2011) Nature

  9. Digital X-ray camera for quality evaluation three-dimensional topographic reconstruction of single crystals of biological macromolecules

    NASA Technical Reports Server (NTRS)

    Borgstahl, Gloria (Inventor); Lovelace, Jeff (Inventor); Snell, Edward Holmes (Inventor); Bellamy, Henry (Inventor)

    2008-01-01

    The present invention provides a digital topography imaging system for determining the crystalline structure of a biological macromolecule, wherein the system employs a charge coupled device (CCD) camera with antiblooming circuitry to directly convert x-ray signals to electrical signals without the use of phosphor and measures reflection profiles from the x-ray emitting source after x-rays are passed through a sample. Methods for using said system are also provided.

  10. Digital monochrome CCD camera for robust pixel correspondant, data compression, and preprocessing in an integrated PC-based image-processing environment

    NASA Astrophysics Data System (ADS)

    Arshad, Norhashim M.; Harvey, David M.; Hobson, Clifford A.

    1996-12-01

    This paper describes the development of a compact digital CCD camera which contains image digitization and processing which interfaces to a personal computer (PC) via a standard enhanced parallel port. Digitizing of precise pixel samples coupled with the provision of putting a single chip FPGA for data processing, became the main digital components of the camera prior to sending the data to the PC. A form of compression scheme is applied so that the digital images may be transferred within the existing parallel port bandwidth. The data is decompressed in the PC environment for a real- time display of the video images using purely native processor resources. Frame capture is built into the camera so that a full uncompressed digital image could be sent for special processing.