The prediction of color appearance using the RLAB color space has been tested for a variety of viewing conditions and stimulus types. These tests have shown that RLAB performs well for complex stimuli and not-so-well for simple stimuli. This article reviews the various psychophysical results, interprets their differences, and describes evolutionary enhancements to the RLAB model that simplify i...

Foreground/background segmentation is an active research area for moving object analysis. We combine two probabilistic approaches one of which estimates foreground/background probabilistic density and the other uses prior knowledge to decompose the colour space. The observed performance advantages are associated with the fusion of operators with completely different basis. Tests on outdoor and ...

An investigation of the color metrics and the complexity of the CIEDE2000 formula shows that CIELAB space is inadequate to represent small-medium color differences. The OSA-UCS (Uniform Color Space) Committee has shown that no space with uniform scale for large color differences exists. Therefore the practical way for color-difference specification is a color-difference formula in a nonuniform ...

Given a color image that was quantized in some hidden color space (termed compression color space) during previous JPEG compression, we aim to estimate this unknown compression color space from the image. This knowledge is potentially useful for color image enhancement and JPEG re-compression. JPEG quantizes the discrete cosine transform (DCT) coefficients of each color plane independently duri...

In this paper a study of the influence of luminance L* at the CIE L* a* b* color space during color segmentation in highly saturated color images is presented. A comparative study is made between the behavior of segmentation in color images using (1) the Euclidean metric of the RGB channels (2) the Euclidean metric of a* and b* in CIE L*a*b* color space and (3) an adaptive color similarity func...

We present comparative results obtained in the context of 24-bit true color image encoding by using searchless vs. search-based fractal compression techniques in a perceptually uniform color space. A pixel in the color space is represented as a vector with each component corresponding to a color channel. The least squares approximation of an image block by an Iterated Function System (IFS) is a...

New electronic imaging devices and products, such as cameras or image retouch software, demand new solutions for image correction and enhancement. In this paper we describe significant modifications to the Retinex approach, a human vision based model proposed by Land, introducing nonlinear filtering and functions to obtain improvements in both local and global contrast of the images, avoiding m...

From a 4-hypercube colour space, spaces of the type hue-saturation-luminance are derived. The hue component may have the topology of a 2-sphere, a 2-torus or a 3-sphere, in several possibilities we consider.

Abst ract. Visual search is the task of nding objects in an image which are described in a high dimensional space, spanned by preattentive features , e.g. orientation, scale, and colour. By using steerable lters this search space may be scanned continouosly, though spanned by discrete feature detectors. Based on this idea, we will show a method for detecting arbitrarily oriented bars from steer...