这篇文章大体上介绍了JPEG文件的结构信息以及它的压缩算法和编码方式。使读者能够对JPEG文件格式有大体上的了解。为读者进一步进行学习JPEG文件压缩做好准备-This article describes the general structure of information as well as a JPEG file compression algorithm and its encoding. Enable the reader to the JPEG file format for general understanding. To further study the reader ready JPEG file compression