论文部分内容阅读
本文研究以零树方法进行小波图象压缩编码，在零树编码各级小波系数前，根据不同分解级小波系数幅值（即幅度的绝对值）间的相关特性，通过以树结构对小波系数的能量估测与排序，不仅优化了码率的分配，提高编码图象ＰＳＮＲ约０．３～０．１ｄＢ，而且加速了编解码过程各约１０％，同时该编码方案仍保持零树编码产生嵌入式码流，支持多码率图象解码．
In this paper, the zero-tree method for wavelet image compression coding is introduced. Before the zero-tree coding of the wavelet coefficients at all levels, according to the correlation between the amplitude of different wavelet coefficients (ie the absolute value of amplitude) Of the energy estimation and ranking, not only to optimize the allocation of the code rate to improve the encoded image PSNR about 0.3 ~ 0.1dB, but also speed up the codec process of about 10%, while the encoding scheme is still maintained zero-tree coding Embedded stream, support for multi-rate image decoding.