EZW Algorithm and Computation of Its Coefficients for Image Compression by Using “Bottom-Up” Approach

Different coding standards for image and video are already in existence such as JPEG for still image and MPEG for video coding. Both the standards utilize block based DCT (discrete cosine transform) technique to remove redundancy. But the problem with DCT approach is that at high compression the decoded image or video suffers from blocking artifacts. To avoid this problem, wavelet transformation is applied over the entire image or image frame. This paper presents a Bottom-Up algorithm by using EZW (Embedded Zerotree Wavelet) transformation technique for getting best compression ratio while maintaining the same quality. Experimental results demonstrate that the method is fast, robust and efficient enough to implement it in still and complex images with significant image compression.