Comparative Study of Contrast Enhancement Techniques for Remote Sensing Images
Shini Antony, Shine P. James · 2015
Satellite images are used in many fields of research. Image enhancement is a technique to improve the contrast of the remote sensing data and to provide better representation of the remote image data. This paper proposes an enhancement method for satellite images which using the concept of dual tree complex wavelet transform , brightness level analysis and principal component analysis(PCA). Here the input image is decomposed into different wavelet subbands and the brightness level is computed in the LL subband using log average luminance. Based on the brightness level value LL subband decomposed into low, middle and high intensity layers. PCA analysis of the each decomposed layer is calculated and finally enhanced image is formed. The performance of this algorithm is compared using measurement of enhancement(EME),PSNR,MAE, and MSE. The experimental results show that the proposed algorithm enhances the overall contrast and visibility of local details better than existing techniques.