基于系数块的改进SPIHT算法

Improved SPIHT Algorithm Based on Block of Coefficients

介绍基于离散小波变换的分层树集合分割排序(SPIHT)编码算法的图像压缩流程和特点,论述了针对该算法进行改进的方向,分析该算法的优缺点,并针对其缺点提出不影响算法整体结构的改进方法,减少编码冗余,提高编码速度。理论分析和实验结果表明,该算法在低比特率时能提高峰值信噪比,在高比特率时也能有较高的峰值信噪比。

This paper introduces the procedure and features for image compression using Set Partitioning In Hierarchical Trees（SPIHT） coding based on DWT,summarizes the aspects of improved SPIHT algorithm,analyzes the advantages and disadvantages of the algorithm profoundly,gives some initial treatments which do not affect the algorithm main frame in accordance with the above disadvantages and develops the algorithm,which can reduce the redundancy and improve the encoding speed.Theoretical analysis and experimental result show the proposed algorithm can enhance the PSNR with low bit rate and maintain high PSNR with high bit rate.