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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.


Papers
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Proceedings Article
21 May 2012
TL;DR: This paper describes the calibration procedure of a CCD digital camera based on the perspective projection method to calibrate the camera in order to extract precise three dimensional information from the images so that they can be used for the computer vision and similar applications which take the images acquired from the camera as an input.
Abstract: This paper describes the calibration procedure of a CCD digital camera based on the perspective projection method. The idea of this method is to calibrate the camera in order to extract precise three dimensional information from the images so that they can be used for the computer vision and similar applications which take the images acquired from the camera as an input. The image capturing process reduces the dimensions of data from three to two. The camera calibration procedure determines which light source is associated with each pixel on the resulting image. Since the camera used in the process is a complex CCD camera, errors resulting from the misaligned lenses and deformations in their structures result in more complex distortions in the acquired image. In order to associate the points in the cameras image space with the locations in a 3D world space the camera projection matrix consisting of the estimated intrinsic and extrinsic parametars is calculated. The calibration process is comprised of capturing calibration images and processing them in order to get the intrinsic and extrinsic camera parameters. The results of the calibration are tested using the test images captured with the same camera. The calibration process was implemented using a MATLAB software package.

58 citations

Patent
Masahito Niikawa1
26 Sep 2002
TL;DR: In this paper, a digital camera which is an image processing apparatus is controlled so that a first image and a second image are acquired for the same subject in different timings and a plurality of correction tables for use in shading correction are prepared in advance in a shading ROM of the camera.
Abstract: A digital camera which is an image processing apparatus is controlled so that a first image and a second image are acquired for the same subject in different timings. A plurality of correction tables for use in shading correction are prepared in advance in a shading ROM of the digital camera. When a first image and a second image are acquired, multiplication of one correction table is performed on both images by a shading correction circuit. As a result of this, a shading correction is effected on both images. The first image and the second image that have been subjected to the shading correction are taken into respective image memories, and after being subjected to a positioning process by a general controller, they are synthesized to generate a synthesized image.

57 citations

Patent
Toni Ostergard1
08 Feb 2001
TL;DR: In this paper, a digital camera for use in a communication device in which the image sensor is formed on a substrate and is mounted on a micro-electromechanical system for movement relative to the camera lens to provide an autofocus capability.
Abstract: A digital camera for use in a communication device in which the image sensor is formed on a substrate and is mounted on a micro-electromechanical system for movement relative to the camera lens to provide an autofocus capability. In addition the lens may be mounted on a micro-electromechanical system for movement relative to the image sensor to provide both an autofocus and a zoom capability.

57 citations

Book ChapterDOI
14 Oct 2000
TL;DR: A presentation interface that pre-warps the image to be projected in such a way that the distortions induced by the projector-screen geometry precisely negate the warping, allowing the projector to be placed anywhere in the presentation room.
Abstract: Projection systems have become the ubiquitous infrastructure for presentation technology. However, unless the projector is precisely aligned to the presentation screen, the resulting image suffers from perspective (keystone) distortions requiring manual optical or digital correction. This tedious process must be repeated whenever the projector or screen is moved and is increasingly relevant given the emerging trend towards highly-portable LCD projection systems. This paper presents a presentation interface that pre-warps the image to be projected in such a way that the distortions induced by the projector-screen geometry precisely negate the warping. An uncalibrated, low-resolution digital camera is used to infer the projector-screen geometry and to automatically determine the pre-warping parameters. This vision-based system is augmented with a natural interface that enables the user to interactively refine the suggested rectification. Arbitrary distortions due to projector placement are negated, allowing the projector (and camera) to be placed anywhere in the presentation room -- for instance, at the side rather than the center of the room. Our solution works with existing projector hardware, and could easily be incorporated into the next generation of LCD projector systems.

57 citations

Journal ArticleDOI
TL;DR: A simple, fast and accurate algorithm for leaf area measurement using image processing is implemented and accuracy is above 99% which is confirmed by comparing the results of proposed algorithm with grid count method.
Abstract: Leaf area plays an important role in plant growth analysis and photosynthesis. Traditionally leaf area is measured by regression equitation, grid count method, gravimetric method and planimeter. In this paper a simple, fast and accurate algorithm for leaf area measurement using image processing is implemented. Image is acquired using digital camera and stored in JPEG format. RGB image is color transformed into CIELAB color space. Color transformed image is segmented using threshold technique. Threshold is calculated using OTSU‟s method. Holes in leaf region are filled using region filling technique. Number of pixels in square object and leaf region are calculated and leaf area is measured by number of pixels statistics. Accuracy of algorithm is above 99% which is confirmed by comparing the results of proposed algorithm with grid count method. General Terms Digital Image Processing, Image Segmentation.

57 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202325
202280
202168
2020166
2019228
2018186