Satellite image contrast and resolution enhancement using discrete wavelet transform and singular value decomposition

Abstract

This paper introduced a new satellite image resolution and contrast enhancement technique which is based on the combination of other two technique named as discrete wavelet transform (DWT) and singular value decomposition (SVD). Satellite images are used in many applications such as in meteorology, oceanography, fishing, agriculture, forestry, geology, education, intelligence and warfare. One of the most important quality factors in images comes from its resolution, here this technique decomposes the input image into the four frequency sub-bands by using DWT and the high frequency sub band images which comes from DWT have been interpolated, by adding the difference image of the input image along with this technique also estimates the modified singular value matrix from the LL sub band of histogram equalized image and LL sub band of input image to obtain brightness enhanced image. In, order to get the new image of better contrast and resolution all these sub bands are combined using inverse DWT. Proposed technique is compared with conventional image equalization techniques such as general histogram equalization (GHE), local histogram equalization (LHE) and also from state-of-the-art technique which is singular value equalization (SVE). Then the experimental results show the supremacy of the proposed method over conventional and state-of-art techniques.