Image Compression Using Discrete Cosine Transform & Discrete Wavelet Transform

A hybrid algorithm for efficient image compression and reconstruction using DCT and DWT

Abstract

This paper describes anarchitecture of DCT and DWT standard of an image compression It is usedspecially for the compression of images where tolerable degradation isrequired.. The discrete cosine transform is a fast transform and has fixedbasis images which gives good compromise between information packing abilityand computational complexity. DWT can be used to reduce the image size withoutlosing much of the resolutions computed and values less than a pre-specifiedthreshold The paper covers some background of wavelet analysis, datacompression and how DCT and DWT can be used for image compression and wepropose a hybrid DWT-DCT algorithm for image compression and reconstructiontaking benefit from the advantages of both algorithms. The algorithm performsthe Discrete Cosine Transform (DCT) on the Discrete Wavelet Transform (DWT)coefficients.