两种静止图像压缩算法研究

Study on 2 still image compression themes

概述了静止图像压缩算法的分类,介绍了各压缩算法的理论基础,阐述了离散余弦算法(DCT)以及离散小波变换(DWT)的基本变换算法,总结了常用于这两种算法的编码方式,并对DCT和DWT进行比较分析.DCT算法简单,运行方便,但有模块效应.DWT算法虽然比较复杂,但由于它有多分辨率分析的优点,从而提高了压缩比,并可以进行渐进传输和对感兴趣区域压缩.最后给出了图像压缩算法的衡量标准.

The classification of still image compression algorithms was presented. It summarizes the theoretical fundament of each image compression algorithm. It explains the basic compression process of discrete cosine transform (DCT) and discrete wavelet transform (DWT). It gives out the usual coding themes of the two transforms and has a comparison of these two algorithms. DCT is simple, convenient, but with effect of module. DCT is a little complicate, but it has multi-differentiate ratio, which improves the compression ratio and makes it possible to transfer image gradually and compress region of interest. At last, it lists the scale standard of image compression.