The Improved Embedded Zerotree Wavelet Coding (EZW) Algorithm
نویسندگان
چکیده
According to the high and low frequency distribution characteristics of wavelet coefficients that were given by Wavelet transform decomposition of images, in this paper, a improved algorithm was proposed for the disadvantage of the classic EZW. The improved algorithm included four steps to improve the coding efficiency of EZW: to predict low-frequency sub-band coding and code after move the forecasted errors by arithmetic coding; set a new threshold value for high-frequency sub-band to improve the quality of quantify; according to the characteristics of the human eye, improve the Diagonal direction threshold to increase the number of zero-tree; according to the table characteristics of the main scan, compressed image by improved huffman coding. Experiments show an improved effectiveness of the algorithm.
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