本人去年在UCLA打酱油的时候曾经要求抓过新浪微博的有关数据。然而要读写这些微博信息和朋友关系，必须要在新浪围脖平台上注册应用。也就是要接触 OAuth 2.0 这个东西。当时基本不懂，今天看到了阮一峰博客上的这篇文章,决定自己动手一试。

ffmpeg is a very fast video and audio converter that can also grab from a live audio/video source. It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter.