Adaptive Multi Scale Enhancement Approach for Non Uniform Images

Abstract

Enhancement of images plays a significant role in digital image processing. The need newlinefor enhancement is because of non-uniformity in brightness and contrast in the newlineacquired images. Among various linear and non-linear approaches to enhancement newlinemethods, histogram equalization is the popular transformation technique to modify the newlinehistogram of an input image. Because the image exhibits non-linear characteristics, newlinethe method failed to produce the effective enhancement of non-uniform images. newlineAlternately, gamma correction is the non-linear transformation technique to provide newlineluminance correction of the image. Human perception is more sensitive to brightness newlineor colour intensities, the numerical value of the exponent power, known as the gamma newlinescale, corrects the luminance value. In the proposed study, the self-adaptive approach newlineof scale value in gamma correction produced improved visibility and preserved the newlinemean brightness. Firstly, the luminance coefficients are obtained from a multi-scale newline2D- discrete wavelet transform. The scale power function is computed for a scale newlinevalue for improved brightness. The power function decimated the scale value to avoid newlineexaggerated brightness. newline