利用离散余弦变换进行图像压缩的方法

采用复杂图像的程序在每一种计算机应用领域都能见到，随着图形图像所需存储量的激增和廉价数字信号处理芯片的出现，有效的图像有损压缩技术开始逐渐脱离专用硬件设备走到桌面计算机中来。该文在分析了音频和视频数据同异点的基础上阐述了一种基于离散余弦变换的图像压缩方法，并给出了算法的基本步骤和一些技巧。实际计算结果表明，通过该算法在极小甚至没有降低图像质量的情况下可获得极高的压缩率。现存的主要问题是计算速度要达到实时运行仍很困难。

A METHOD FOR PICTURE COMPRESSION USING DISCRETE COSINE TRANSFORM

Softwares adopted complicated pictures are common in every area of computer application. As the demanding of storage capacity by photographs increases sharply and numerical signal processing units become more and more cheap, effective techniques of lossy compression are generally seperated from some special hardwares and applied to table compter systems. In this paper, the authors first analyze the similarities and differences of audio and video data, then expound a picture compression technique based upon discrete cosine transform (DCT), and finally give detailed steps and some basic skills of its algorithm. Practical computing results by this technique show that very high compression ratios are available under minimum lowering or even no lowering of raw picture quality. The main extant problem is computing speed. It is very difficult to reach real time operation at present.