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...

In this paper a novel method for machine-based black and white films colorization is presented. The kernel of the proposed scheme is a trained artificial neural network which maps the frame pixels from a grayscale space into a color space. We employ the texture coding method to capture the line/texture characteristics of each pixel as its most significant gray scale space feature, and using tha...

When light is reflected from object surface, its spectral characteristics will be affected by the surface’s elemental composition, and its polarimetric characteristics will be governed by the surface’s roughness and conductance. Polarimetric and multispectral imaging can provide complementary discriminative information in applications such as object separation. However, few methods have been pr...

In photorealistic image synthesis the radiative transfer equation is often not solved by simulating every wavelength of light, but instead by computing tristimulus transport, for instance using sRGB primaries as a basis. This choice is convenient, because input texture data is usually stored in RGB colour spaces. However, there are problems with this approach which are often overlooked or ignor...