High Resolution Satellite Image Compression using DCT and EZW

Abstract

Image Compression has played vital role for efficient image storage, retrieval and transmission. In today’s digital world, images are captured with high wavelength camera lens for better quality, but requires more storage space. Comparison is carried out on multi spectral satellite images using DCT and EZW on basis of compression ratio, PSNR and MSE. DCT performs efficiently at medium bit rates giving compression ratio over 99% and low PSNR whereas EZW performs well at low bit rate giving efficient compression ratio. Disadvantage with DCT is that only spatial correlation of the pixels is considered and the neighborhood correlation is neglected, on the other hand, use of larger EZW wavelet functions produced blurred images.

Keywords: DCT, EZW, LANDSAT image compression, Satellite Imaging