IMPROVED IMAGE COMPRESSION BASED ON FEED-FORWARD ADAPTIVE DOWNSAMPLING ALGORITHM

Abstract

All the visual signals used in internet, mobile and multimedia applications are needed to be coded at very low bit rates, without affecting much the quality of image or video data. To achieve a very low bit rate and very high compression ratio the image can be downsampled prior to compression and the full resolution image can be obtained by estimating the missing portion after decompression with reward of better PSNR. In this paper an attempt has been made to design an improved image compression system based on the feed forward adaptive downsampling algorithm considering the visual significance of the image. The mathematical basis has been established for visual significance and downsampling parameters, the mathematical formulation has also been established to get the PSNR value reconstructed image, without the actual reconstruction on the downsampled image in terms of known pixel values, remained after downsampling. Through this paper a fast image compression method is proposed which is having high compression ratio, feed-forward nature, acceptable signal-to-noise ratio and is application oriented. This method can also be used further for variable bit rate application.