摘要
嵌入式零树小波编码算法(EZW)为了确定一系数是零树根还是孤立零,必须对该系数进行反复多次扫描,不仅耗时,而且造成二进制符号流中存在大量冗余.在研究Shapiro零树图像编码算法的基础上,通过对重要系数的全新界定和精确量化,增加零树的数量,减少孤立零点,从而缩短搜索扫描编码时间、提高压缩比.实验结果表明:改进的嵌入式零树小波编码算法在峰值信噪比、编码时间、图像恢复质量等方面都优于J.M.Shapiro最初提出的EZW算法.
The improved image coding algorithm was put forward to improve the deficiency of embedded zerotree wavelet(EZW) by redefining significant coefficient and exacting quantization.The algorithm increased the numbers of zerotree and improved the coding efficiency.In comparison to the previous EZW algorithm,the results of the experiment showed that the new algorithm performed better in the peak signal-to-noise ratio(PSNR) and coding speed.
出处
《南京晓庄学院学报》
2009年第3期82-85,共4页
Journal of Nanjing Xiaozhuang University
关键词
小波变换
零树
峰值信噪比
编码时间
wavelet transforms
zerotree
the peak signal-to-noise ratio(PSNR)
coding speed
