一种新的小波域彩色图像压缩编码算法

A New Color Image Coding Scheme in DWT Domain

为了快速地进行彩色图像压缩，提出了一种基于视觉掩蔽与色彩相关的小波变换域彩色图像压缩编码算法。该算法首先在RGB空间内对原始图像的彩色分量进行小波变换，并结合视觉掩蔽特性对不同区域内的小波系数进行加权处理；然后将经过加权处理的小波系数转换到自定义的Y’U’V’空间；最后依据色彩相关性来构造扩展零树结构，并利用改进的嵌入零树小波（EZW）方案在Y’U’V’空间内对小波系数进行嵌入零树编码。仿真实验结果表明，该彩色图像编码方法是一种高效的图像压缩算法，其编解码时间较CZW算法、CEZW算法缩短约1／3-1／4。

In this paper, a now color image compression algorithm in DWT domain is proposed, in which the visual masking and the correlation between color components are utilized. Firstly, the discrete wavelet transform is performed on three different color components in RGB color space, and the wavelet coefficients are weighed based on the human visual masking. Then weighed wavelet coefficients are converted to user＇ s defined Y＇U＇V＇ color space. Finally, the wavelet coefficients are progressively encoded in Y＇U＇V＇ Color space by the extended zerotree structure and the improved EZW scheme. Experimental results show that the new color image compression scheme performs better than that of CEZW and CZW in the aspect of recovery image quality and coding/decoding time.