S. Baluta, M. Zoran, M. Pearsica, An improvement of filtering techniques designed to correct the non-uniform illumination effect of images, J. Optoelectron. Adv. Mater., 10/11 (2008) 3106-3110

Title: An improvement of filtering techniques designed to correct the non-uniform illumination effect of images

Abstract: The quality of some images might be reduced because of non-uniform illumination effect. In order to perform illumination correction, can be successfully used homomorphic filtering techniques. Most of the existing published papers on these methods for image enhancement and/or correction, are restricted to present only the qualitative aspects of this generalized technique. The aim of this article is to develop this subject by computing the appropriate filter's parameters for better monitoring of some image's quality characteristics such as the standard deviation, measured in an image region which is supposed to have a constant reflectance.

Key words: Image generation process; Image enhancement; Image processing; Image quality; Homomorphic filtering; Illumination; Spatial frequencies; Standard deviation