121,511 research outputs found

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

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

    Conclusion of Viking Lander Imaging Investigation: Picture catalog of experiment data record

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    The images returned by the two Viking landers during the Viking Survey Mission are presented in this report. Listing of supplemental information which describe the conditions under which the images were acquired are included. Subsets of the images are listed in a variety of sequences to aid in locating images of interest. The format and organization of the digital magnetic tape storage of the images are described. A brief description of the mission and the camera system is also included

    Random on-board pixel sampling (ROPS) X-ray Camera

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    Recent advances in compressed sensing theory and algorithms offer new possibilities for high-speed X-ray camera design. In many CMOS cameras, each pixel has an independent on-board circuit that includes an amplifier, noise rejection, signal shaper, an analog-to-digital converter (ADC), and optional in-pixel storage. When X-ray images are sparse, i.e., when one of the following cases is true: (a.) The number of pixels with true X-ray hits is much smaller than the total number of pixels; (b.) The X-ray information is redundant; or (c.) Some prior knowledge about the X-ray images exists, sparse sampling may be allowed. Here we first illustrate the feasibility of random on-board pixel sampling (ROPS) using an existing set of X-ray images, followed by a discussion about signal to noise as a function of pixel size. Next, we describe a possible circuit architecture to achieve random pixel access and in-pixel storage. The combination of a multilayer architecture, sparse on-chip sampling, and computational image techniques, is expected to facilitate the development and applications of high-speed X-ray camera technology.Comment: 9 pages, 6 figures, Presented in 19th iWoRI

    Method for acquiring, storing and analyzing crystal images

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    A system utilizing a digital computer for acquiring, storing and evaluating crystal images. The system includes a video camera (12) which produces a digital output signal representative of a crystal specimen positioned within its focal window (16). The digitized output from the camera (12) is then stored on data storage media (32) together with other parameters inputted by a technician and relevant to the crystal specimen. Preferably, the digitized images are stored on removable media (32) while the parameters for different crystal specimens are maintained in a database (40) with indices to the digitized optical images on the other data storage media (32). Computer software is then utilized to identify not only the presence and number of crystals and the edges of the crystal specimens from the optical image, but to also rate the crystal specimens by various parameters, such as edge straightness, polygon formation, aspect ratio, surface clarity, crystal cracks and other defects or lack thereof, and other parameters relevant to the quality of the crystals

    Digital Forensic Technique for Multiple Compression based JPEG Forgery

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    In today's digital world digital multimedia like, images, voice-notes and videos etc., are the major source of information/data exchange. The authenticity of these multimedia is greatly vital in the legitimate business, media world and broadcast industry. However, with enormous multiplication of ease, simple-to-utilize data manipulation tools and softwares lead to the faithfulness of digital images is in question. In our work, we propose a technique to identify digital forgery or tampering in JPEG (Joint Photographic Experts Group) images which are based on multiple compression factor. We are dealing with the JPEG images on the grounds because JPEG is the standard storage format used in almost all present day digital devices like digital camera, camcorder, mobile devices and other image acquisition devices. JPEG compresses a image to the best compression in-order to manage the storage requirement. JPEG is a lossy compression standard. At the point when an assailant or criminal modifies some region/part of a JPEG image by any image processing tools and save it, the modified region of the image is doubly-compressed. In our work, we exploit this multiple compression in JPEG images to distinguish digital forgery or falsification

    Viking Lander imaging investigation: Picture catalog of primary mission experiment data record

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    All the images returned by the two Viking Landers during the primary phase of the Viking Mission are presented. Listings of supplemental information which described the conditions under which the images were acquired are included together with skyline drawings which show where the images are positioned in the field of view of the cameras. Subsets of the images are listed in a variety of sequences to aid in locating images of interest. The format and organization of the digital magnetic tape storage of the images are described. The mission and the camera system are briefly described

    Mallory archival filmstrip registration

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    This project will create a method for importing and registering archival filmstrips for analysis and digital storage. Images will be registered in the horizontal and vertical directions with subpixel accuracy, and a method for rotational registration will also be developed to compensate for camera movement. In addition, the three filmstrips used to develop the programs will be analyzed for possible sightings of climbers scaling Mount Everest in 1924

    Electronic Still Camera

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    A handheld, programmable, digital camera is disclosed that supports a variety of sensors and has program control over the system components to provide versatility. The camera uses a high performance design which produces near film quality images from an electronic system. The optical system of the camera incorporates a conventional camera body that was slightly modified, thus permitting the use of conventional camera accessories, such as telephoto lenses, wide-angle lenses, auto-focusing circuitry, auto-exposure circuitry, flash units, and the like. An image sensor, such as a charge coupled device ('CCD') collects the photons that pass through the camera aperture when the shutter is opened, and produces an analog electrical signal indicative of the image. The analog image signal is read out of the CCD and is processed by preamplifier circuitry, a correlated double sampler, and a sample and hold circuit before it is converted to a digital signal. The analog-to-digital converter has an accuracy of eight bits to insure accuracy during the conversion. Two types of data ports are included for two different data transfer needs. One data port comprises a general purpose industrial standard port and the other a high speed/high performance application specific port. The system uses removable hard disks as its permanent storage media. The hard disk receives the digital image signal from the memory buffer and correlates the image signal with other sensed parameters, such as longitudinal or other information. When the storage capacity of the hard disk has been filled, the disk can be replaced with a new disk

    life More Photographic; mapping the networked image

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    Twenty two years since the arrival of the first consumer digital camera (Tatsuno 36) Western culture is now characterised by ubiquitous photography. The disappearance of the camera inside the mobile phone has ensured that even the most banal moments of the day can become a point of photographic reverie, potentially shared instantly. Supported by the increased affordability of computers, digital storage and access to broadband, consumers are provided with new opportunities for the capture and transmission of images, particularly online where snapshot photography is being transformed from an individual to a communal activity. As the digital image proliferates online and becomes increasingly delivered via networks, numerous practices emerge surrounding the image’s transmission, encoding, ordering and reception. Informing these practices is a growing cultural shift towards a conception of the Internet as a platform for sharing and collaboration, supported by a mosaic of technologies termed Web 2.0
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