Image conversion

About: Image conversion is a research topic. Over the lifetime, 2490 publications have been published within this topic receiving 19077 citations.

Colour-to-Greyscale Image Conversion by Linear Anisotropic Diffusion of Perceptual Colour Metrics

Abstract: We present an algorithm for conversion of colour images to greyscale. The underlying idea is that local perceptual colour differences in the colour image should translate into local differences in greylevel in the greyscale image. This is obtained by constructing a gradient for the greyscale image from the eigenvalues and eigenvectors of the structure tensor of the colour image, which, in turn, is computed by means of perceptual colour difference metrics. The greyscale image is then constructed from the gradient by means of linear anisotropic diffusion, where the diffusion tensor is constructed from the same structure tensor. By means of psychometric experiments, it is found that the algorithm gives the most accurate image reproduction when used with the $\triangle E_{99}$ colour metric, and that it performs at the level of, or better than, other state-of-the-art spatial algorithms. Surprisingly, the only algorithm that can compete in terms of accuracy is a simple luminance map computed as the $L^{*}$ channel of the image represented in the CIELAB colour space.

Personal Computer Based Image Processing With Halftoning

Abstract: A versatile and useful personal computer based procedure to generate halftone representation of digitized image data is presented. This feature provides limited interactive image processing capability for a basic personal computer work station without having to acquire a video monitor and a digital-to-analog converter board. The generated halftone images can be displayed on the standard dot-addressable graphics monitor, and/or they can be printed on regular paper via an associated printer. The halftoning procedure is based on an error diffusion technique in which dots are produced randomly, one at a time, based on both the local gray level value and some accumulated measure of the error due to previous assignments. The key elements in halftoning, such as dynamic, spatial, and display medium resolutions, are defined, and the mathematical correspondence among them is established.

Image converter, image conversion method, and recording medium

Abstract: PROBLEM TO BE SOLVED: To provide an image converter and method, and a recording medium for decoding compressed data subjected to reduction processing without the need for a frame memory having a capacity of one screen image. SOLUTION: The image converter applies reduction processing to each unit block and provides an output of a result so as to avoid the size of a work memory required for the reduction processing from being increased even when the size of an input image increases. Further, the image converter decodes and reduces compressed data by each minimum unit at the same time so as to store only a reduced and decoded image. Thus, the downsized converter, reduced cost, and saved power consumption are attained. COPYRIGHT: (C)2004,JPO

Driving support device for vehicle

Abstract: PROBLEM TO BE SOLVED: To confirm the rearward view of a vehicle by viewing an image, in place of using a rearward view mirror, in a driving support device therefor. SOLUTION: A display control means (14) includes a first image conversion means (24) that converts a rearward image imaged by a rearward imaging means (12) into a rearward image adjacent to the vehicle, and a second conversion means (25) that converts the rearward image imaged by the rearward imaging means (12) into a rearward image of the region more distant from the vehicle than the region of the image converted by the first image conversion means (24). In the display control means, the image converted by the first image conversion means (24) is displayed on a display means (16), when the range position detected by a range position detection means (17) is in a backward range; whereas the image converted by the second image conversion means (25) is displayed on the display means (16), when the range position detected by the range-position detection means (17) is in a forward range. COPYRIGHT: (C)2011,JPO&INPIT

X-ray cross-sectional plane examination apparatus

Abstract: PROBLEM TO BE SOLVED: To provide an X-ray cross-sectional plane examination apparatus which can obtain clear X-ray images using a limited number of parts and a simple structure and without the use of a special optical system. SOLUTION: This apparatus is provided with an X-ray source 2 for irradiating a subject S with X rays, a first rotating means (rotating stage 4) for revolving the specimen, an X ray-optical image conversion means (X rays I.I5) to convert a fluoroscopic image transmitted through the specimen into an optical image, an image pickup means 8 for picking up the optical image, a second rotating means (rotation mechanism 6) for rotating the imaging means synchronized with the first rotation means and an image processing means 9, which composites a plurality of images at the angles of rotation to generate a tomographic image of a subject. The fluoroscopic image is detected by rotating the subject, while the imaging means for obtaining the optical image from transmission X rays is rotated to synchronize the rotation of the subject, thereby obtaining an X-ray image with a higher sharpness.