Adaptive gamma correction for contrast enhancement of remote sensing images

Abstract

Contrast magnification is a critical parameter of image enhancement. Remote sensing images are distance captured images, so they naturally have very low contrast as compared to other images. In this paper a very simple and efficient technique based on adaptive gamma correction and Discrete cosine transform(DCT) is proposed which can bring out the maximum information present in the image and enhance the contrast of the image very well. We first apply an adaptive gamma correction which enhances the image globally and than high frequency components of DCT transformation are further altered to intensify the minute details of the image. Proposed method is judged on the basis of visual quality and numerical parameters compared with the other existing techniques. The results obtained for proposed technique surpasses all the other methods both qualitatively and quantitatively.