The Beltrami geometrical framework for scale-space flows is generalized to nontrivial color space geometries and implemented in analysis and processing of color images. We demonstrate how various models of color perception, interpreted as geometries of the color space, result in different enhanced processing schemes.

Many High-Dynamic-Range (HDR) rendering techniques have been developed. Of these, the image color appearance model, iCAM, is a typical HDR image rendering algorithm. HDR rendering methods normally require a tone compression process and include many color space transformations from the RGB signal of an input image to the RGB signal of output devices for the realistic depiction of a captured imag...

In this paper, we present a method for color reduction of Persian carpet cartoons that increases both speed and accuracy of editing. Carpet cartoons are in two categories: machine-printed and hand-drawn. Hand-drawn cartoons are divided into two groups: before and after discretization. The purpose of this study is color reduction of hand-drawn cartoons before discretization. The proposed algorit...

A single sensor color imaging device has a color filter array (CFA) laid on top of its photodiodes, which spatially samples bandpassed spectral responses. Hence, with the popular Bayer pattern, at every pixel site either red, green or blue light is measured. A process known as demosaicing interpolates the vector-valued color image from the scalar-valued sensor output, termed here as the Bayer i...

The most popular technique for image retrieval in a database of color images is the comparison of images based on their color histogram. The color histogram describes the distribution of colors in the color space of a color image. In the most image retrieval systems, the color histogram is used to compute similarities between the query image and all the images in the database. But, small change...

Color quantization is an important part of image processing, image formation, and related research. This paper presents a novel color image quantization algorithm which addresses the question of how to incorporate principles of human perception of color variation into the process of quantization. The color variation measure, calculated first in CIE Lab color space, is used to evaluate color var...

Color histograms are the most commonly used features for image retrieval due to the good attributes of image translation and rotation invariance. However the traditional color histogram features are usually short of spatial structural information which may cause error retrieval results. This paper presents a color image retrieval method based on Weighted DCT Spatial Combination Histogram (WDSCH...

This paper describes two classic style methods to analyze and segment the color space. The RGB space method includes color space pyramiding, low-pass filtering, 3-D object labeling and property calculation to acquire a proper number of colors and a good initial estimate of center positions, then fuzzy cmeans algorithm can be used to optimally cluster the color space distribution points. The sec...

We present an interactive image enhancement technique to adjust the global color composition of an image by finding and replacing color gradients. We show how color gradient transformations can perform the basic operations of color editing. To recolor an image, the user designates a mapping of source color gradients to corresponding target color gradients. Each color gradient can be represented...