Digital camera

About: Digital camera is a research topic. Over the lifetime, 12169 publications have been published within this topic receiving 137431 citations. The topic is also known as: digicam & digital still camera.

Method and system for compensating for parallax in multiple camera systems

Abstract: A camera array captures plural component images which are combined into a single scene In one embodiment, each camera of the array is a fixed digital camera The images from each camera are warped to a common coordinate system and the disparity between overlapping images is reduced using disparity estimation techniques

A study of digital camera colorimetric characterization based on polynomial modeling

Abstract: The digital camera is a powerful tool to capture images for use in image processing and colour communication. However, the RGB signals generated by a digital camera are device-dependent, i.e., different digital cameras produce different RGB responses for the same scene. Furthermore, they are not colorimetric, i.e., the output RGB signals do not directly correspond to the device-independent tristimulus values based on the CIE standard colorimetric observer. One approach for deriving a colorimetric mapping between camera RGB signals and CIE tristimulus values uses polynomial modeling and is described here. The least squares fitting technique was used to derive the coefficients of 3 × n polynomial transfer matrices, yielding a modeling accuracy typically averaging 1 ΔE units in CMC(1:1) when a 3 × 11 matrix is used. Experiments were carried out to investigate the repeatability of the digitizing system, characterization performance when different polynomials were used, modeling accuracy when 8-bit and 12-bit RGB data were used for characterization, and the number of reference samples needed to achieve a reasonable degree of modeling accuracy. Choice of characterization target and media and their effect on metamerism have been examined. It is demonstrated that a model is dependent upon both media and colorant, and applying a model to other media/colorants can lead to serious eye–camera metamerism problems. © 2001 John Wiley & Sons, Inc. Col Res Appl, 26, 76–84, 2001

Image display and archiving system and method

Abstract: A system 10 and methods for acquiring and archiving images derived from multiple sources with minimal operator interaction and understanding of the archiving computer 11. The system 10 and methods provide for reception of digitized images via modem 24 from a remote source, and the input of images from local sources including a digital photographic image source 25 such as a digital camera or 35 millimeter digitizing camera data back, an optical scanner 23, and digitized images previously stored on magneto-optical disk or digital audio tape. The system 10 also archives and distributes image and document data to multiple destinations, including a magneto-optical drive 22, digital or hard disk drive 15, and to laser or photographic quality continuous tone printers 26, 27. One key aspect of the system 10 and methods is that the operator is not given access to the operating system of the computer 11 and can only perform a predetermined set of functions that correspond to graphical icons 30 disposed on the computer desktop 17 (monitor 12). Each of the icons 30 launches a set of linked macro functions that initialize the modem 24, control data transfer, format the received image data into a predetermined format, attach textual data to the image files, and automatically archive or print the files. Submenus are provided during operation that permit certain selected actions related to the macro that is being run.

Imaging with a small number of photons

Abstract: Low-light-level imaging techniques have application in many diverse fields, ranging from biological sciences to security. A high-quality digital camera based on a multi-megapixel array will typically record an image by collecting of order 105 photons per pixel, but by how much could this photon flux be reduced? In this work we demonstrate a single-photon imaging system based on a time-gated intensified camera from which the image of an object can be inferred from very few detected photons. We show that a ghost-imaging configuration, where the image is obtained from photons that have never interacted with the object, is a useful approach for obtaining images with high signal-to-noise ratios. The use of heralded single photons ensures that the background counts can be virtually eliminated from the recorded images. By applying principles of image compression and associated image reconstruction, we obtain high-quality images of objects from raw data formed from an average of fewer than one detected photon per image pixel.

Image Forgery Localization via Fine-Grained Analysis of CFA Artifacts

Abstract: In this paper, a forensic tool able to discriminate between original and forged regions in an image captured by a digital camera is presented. We make the assumption that the image is acquired using a Color Filter Array, and that tampering removes the artifacts due to the demosaicking algorithm. The proposed method is based on a new feature measuring the presence of demosaicking artifacts at a local level, and on a new statistical model allowing to derive the tampering probability of each 2 × 2 image block without requiring to know a priori the position of the forged region. Experimental results on different cameras equipped with different demosaicking algorithms demonstrate both the validity of the theoretical model and the effectiveness of our scheme.