一种改进的嵌入零树小波编码算法RA-EZW  

Study of RA-EZW-based image coding algorithm

作　　者：金海[1] 姜文超[1] 陶文兵[1] 王抒[2] 

机构地区：[1]华中科技大学计算机科学与技术学院,湖北武汉430074 [2]曲阜师范大学计算机学院,山东曲阜273165

出　　处：《华中科技大学学报（自然科学版）》2006年第1期39-41,共3页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：中国教育科研网格计划ChinaGrid资助项目(CG2003-GA001)

摘　　要：针对嵌入零树小波编码算法(EZW)中不同阈值下相同系数被多次扫描编码的不足,通过对小波变换后系数幅值的变换调整,减少孤立零点,增加零树的数量,从而提高编码效率.实验结果表明:基于幅值变换的嵌入零树小波编码算法在信噪比、编/解码时间、图像恢复质量等方面都高于EZW算法,在恢复质量方面,比特率较低时效果尤为明显.RA-EZW（embedded zerotree wavelet based range-adjusting） was presented on the basis of EZW＇s deficiency. The method decreased the coding numbers of the same coefficient under the different threshold by range-adjusting to improve the coding efficiency. In comparison with the previous EZW algorithm, the experiment results showed that the new scheme performed better in compression ratio, image quality, coding speed and coding efficiency, especially in the condition of low bit-ratio.

关 键 词：嵌入零树小波编码 幅值调整 基于幅值调整的嵌入零树小波编码 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]