说明：  本上传是在matlab环境下实现图像的基于DCT的JPEG压缩，上传内容包括主程序、子函数和实验原理pdf。可供朋友学习与参考。
(This upload is in the matlab environment to achieve the image DCT-based JPEG compression, upload content, including the main program, subroutine and experimental principles of pdf. For friends to study and reference.)