Improved set-partitioning embedded block scheme for still image compression

摘要

In the last few years, wavelet-based still image compression schemes have become one of the most popular fields of research. Several powerful methods of encoding the wavelet coefficients have been proposed and set-partitioning embedded block (SPECK) is one of the most popular techniques. We propose a method called HSPECK (Huffman SPECK), which is based on SPECK to further improve the compression ratio. By observation, we are able to establish the probability distribution over the significance pattern of four subblocks generated successively along the wavelet decomposition process. Therefore, the Huffman coding scheme can then be employed for coding wavelet coefficients. The experimental results show that under the same peak signal-to-noise ratio, the bit rates via the proposed approach improve between 6.1% and 14.9%.