Abstract:

A new embedded wavelet image coding scheme is proposed to improve the efficiency of EZW which was founded by Shapiro: divide subbands into important ones and unimportant ones. To avoid the repetitive scans,it is necessary to scan only the important subbands,which will decrease the number of zerotrees needed to scan and code. Besides,the resorting of the subordinate list,which pays a lot but little benefits is given up. Experiments show the simple algorithm saves code streams,speeds up the coding and decoding course,and increases the efficiency without losing the precision of coding. Moreover,we analyse and study some improved algorithms put forward recently,and compare the algorithm in this paper with them.

Key words: wavelet;embedded;EZW coding;repetitive scan;subband division