Image conversion

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

Perceptually Consistent Color-to-Gray Image Conversion.

Abstract: In this paper, we propose a color to grayscale image conversion algorithm (C2G) that aims to preserve the perceptual properties of the color image as much as possible. To this end, we propose measures for two perceptual properties based on contemporary research in vision science: brightness and multi-scale contrast. The brightness measurement is based on the idea that the brightness of a grayscale image will affect the perception of the probability of color information. The color contrast measurement is based on the idea that the contrast of a given pixel to its surroundings can be measured as a linear combination of color contrast at different scales. Based on these measures we propose a graph based optimization framework to balance the brightness and contrast measurements. To solve the optimization, an $\ell_1$-norm based method is provided which converts color discontinuities to brightness discontinuities. To validate our methods, we evaluate against the existing \cadik and Color250 datasets, and against NeoColor, a new dataset that improves over existing C2G datasets. NeoColor contains around 300 images from typical C2G scenarios, including: commercial photograph, printing, books, magazines, masterpiece artworks and computer designed graphics. We show improvements in metrics of performance, and further through a user study, we validate the performance of both the algorithm and the metric.

Method and device for image processing

Abstract: PROBLEM TO BE SOLVED: To perform image conversion at a low sampling frequency without including high spatial frequencies. SOLUTION: One or more image IR(x,y) of low resolution are generated from one input image I1(x,y) and a plurality of images of different resolution including the input image are properly selected and geometrically converted to obtain output images 0(p,q). Consequently, images of low resolution can be converted into converted parts of low sampling frequency and deterioration in picture quality resulting from high spatial frequencies can be suppressed.

Real time digital radiography

Abstract: PROBLEM TO BE SOLVED: To obtain the real time DR (digital radiography device by using a television camera whose operating condition is optimized so as to receive a stable and excellent image. SOLUTION: This DR device is provided with an X ray generating source generating an X ray emitted onto an object 3, an image conversion means 4 converting an X ray image of the reagent into an optical image, and an optical system 5 forming the optical image to an image pickup tube of a television camera 6. In this case, the DR device is provided with a target voltage control means which has a tomology mode to obtain a tomology image and a plurality of image pickup modes to obtain an image pickup image as scanning modes for the image pickup tube, and controls a target voltage so as to satisfy a relation of VS>=VF, where VS is a target voltage applied to an image pickup tube when the scanning mode is the image pickup mode and VF is a target voltage applied to the image pickup tube when the scanning mode is the tomology mode, and controls the target voltage to be increased corresponding to a decreased frame number depending on each image pickup mode having a different frame number per each second. Thus, high S/N and a wide dynamic range are attained for each scanning mode.

Image processor, image processing method, image output method, program, program recording medium and image output system

Abstract: PROBLEM TO BE SOLVED: To output images having approximately the same density contrast according to image output units having different image observing conditions or different image output characteristics. SOLUTION: Image signals are related to perception indexes by a first nonlinear image signal conversion. A frequency emphasis or a frequency de-emphasis is applied so as to have natural gradation characteristics by a frequency processing. The image processing condition concerning the frequency processing is determined, based on output gradation characteristics and the reception index ranges about a first and second image output units or image observing condition information. The image signals are converted so as to correspond to the output gradation characteristics about the second image output unit by a second nonlinear image signal conversion. Using the above image conversion processes, images having approximately the same density contrast can be outputted even between different image output units. COPYRIGHT: (C)2004,JPO&NCIPI

Medical image conversion method and equipment

Abstract: The invention relates to a medical image conversion method. The method comprises steps that interpolation of original pixel values of an original coordinate system is carried out on the basis of a search table to acquire a pixel value of each target pixel of a target coordinate system, and the position of a boundary of each target pixel of the target coordinate system in the original coordinate system is recorded by the search table. The invention further relates to the medical image conversion equipment.