The algorithm of the JPEG image compression based on DCT was discussed. Then simulation experiments were done with MATLAB 6.5 and rate distortion curve was drawn with different compression to the same image Lena.

• 首先介绍了基于离散余弦变换的JPEG图像压缩编码算法；接着用MATLAB6.；5对标准灰度图像进行仿真；并对同一幅Lena图像做不同的压缩；绘制了率失真曲线。