基于分形和小波的混合图像压缩编码

Hybrid Fractal and Wavelet Coding for Image Compression

从近年来受人瞩目的分形和小波图像压缩方法出发，分析了两种图像压缩方法的特点及利弊． 运用小波变换及ＤＣＴ变换下的分形压缩图像方法，提高了编码速度，得到了较高的压缩比和信噪比，但重构图像质量还存在块状效应． 为此，提出了几种结合起来的综合方法，进一步提高了图像的质量，在压缩比和信噪比及匹配速度之间取得了良好的折衷．

This thesis deals with the Fractal and Wavelet Image compression which is a hot research topic in recent years. Their characteristics as well as their merits and demerits are analyzed. Fractal Image compression is carried out after DWT or DCT to improve coding speed and to obtain higher CR and PSNR, but the quality of reconstructed Images is not so satisfactory. Thus it has been proposed that DCT, DWT and Fractal be combined together for Image compression. This method can improve the quality of reconstructed Images further and get fine compromise between CR and PSNR.