A new zerotree structure for color image compression based on DWT and VQ

Colour images are widely used in computer applications. Uncompressed digital images require considerable storage capacity and transmission bandwidth. Efficient image compression solutions are becoming more critical with the recent growth of data intensive, multimedia-based web applications. DCT (relative to the DFT) has the advantages of real-valued, better energy compaction (much of the signal energy can be represented by only a few coefficients), experimentally observed to work well and coefficients are nearly uncorrelated. Fractal coding is a kind of VQ coding but Less than stellar compression ratio for ´good´ image reconstruction. In this paper we implement colour image compression using Discrete Cosine Transform (DCT), VQ coding and a new proposed method that merges DCT and wavelet transform is implemented. Experiment results showed that the performance of new proposed algorithm is effective and can obtain very high compression ration.