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在深入研究尺度小波变换和嵌入式小波零树压缩编码算法的基础上 ,探讨了一种改进的小波零树编码算法 .通过采用基于嵌入式零树预测扫描算法的改进小波变换编码方法 ,对小波分解的低频子带图像采用DPCM预测编码 ,高频子带图像采用了改进的取消重要系数排序的零树预测扫描算法进行压缩编码 ,使之既具有原零树算法良好的压缩品质 ,同时也简化了原压缩算法 ,提高了该算法的适应性 ,与 JPEG压缩相比 ,它消除了JPEG图像在高压缩比下的方块效应 ,取得了令人满意的实验效果
Based on the further study of the standard wavelet transform and embedded wavelet zerotree compression coding algorithm, an improved wavelet zerotree coding algorithm is discussed. By using the improved wavelet transform coding method based on embedded zerotree-prediction scanning algorithm, The decomposed low-frequency sub-band images are encoded by DPCM, and the high-frequency sub-band images are compressed and encoded by the improved zero-tree prediction scanning algorithm with the cancellation of significant coefficients, so that both the original zero-tree algorithm has good compression quality and simplification The original compression algorithm improves the adaptability of the algorithm. Compared with JPEG compression, it eliminates the square effect of JPEG images under high compression ratio and achieves satisfactory experimental results