二维提升的CDF(1,3)小波结合改进的SPIHT的渐进性无损图像压缩方法

针对传统小波变换计算复杂的缺点和多级树集合分裂算法(SPIHT)编码过程重复运算、存储量大的问题,提出了一种二维提升的CDF(1,3)小波结合改进的SPIHT的渐进性无损图像压缩方法。对整数CDF(1,3)双正交小波变换实现二维提升,利用提升的小波对图像做变换,提高了运算速度、便于硬件实现。对SPIHT算法加以改进,根据各个子图像的不同特点,改变扫描路线,采用四路并行分块处理的方法,提高了编码速度,降低了编解码过程的运算复杂度和时间消耗。利用提升的CDF(1,3)小波变换结合改进的SPIHT实现了渐进性无损图像压缩,证明了二维提升方案的有效性。

Progressively lossless image compression algorithm based on two-dimension lifting scheme CDF(1, 3)wavelet transform and improved SPIHT

In view of the problems of complicated convolution process of wavelet transform,repeated calculations and a large number of needed memories of SPIHT algorithm,The progressively lossless image compression algorithm based on twodimension lifting scheme CDF(1,3) wavelet transform and improved SPIHT is proposed.CDF(1,3) wavelet is two-dimension lifted.The image is translated by lifting scheme CDF(1,3) wavelet transform,fast,easy to implemented by hardware.SPIHT algorithm is improved by the differ characteristic of every image,to change scan path,and improve coding speed by the processing method of four parallel divided block,the operation complex degree and time expend of coding and decoding are reduced.The fast lossless image compression algorithm is realized by two-dimension lifting scheme CDF(1,3) wavelet transform and improved SPIHT.The validity of two-dimension lifting scheme is tested.