使用 Video Toolbox 进行H.264编码
这个demo实现了H.264的硬件编码与硬件解码。编码视频来源为摄像头，调试的时候最好横屏
1、点击start按钮开始录像（把录像编码成H.h264存入沙盒中，文件名为：test.h264）
2、点击stop按钮停止录像。
3、点击play按钮播放录像（从沙盒中读取test.h264文件并解码播放）
4、点击stop停止播放、清除播放对象
沙盒中的test.h264文件可以通过设备连接电脑后打开iTunes，选定自己的设备，在文件共享那里可以找到第一步保存的test.h264源码文件
把test.h264文件拷到电脑中后缀名改为.mov，用MPlayerX可以直接播放
通过参考以下博客、github上的demo与苹果官方的资料整理出这个集H.264编码与解码于一身的demo供大家参考
参考博客：
http://www.jianshu.com/p/a6530fa46a88
http://www.zhihu.com/question/20692215/answer/37458146
苹果官方参考资料：
WWDC2014 513《direct access to media encoding and decoding》
参考开源项目：
https://github.com/stevenyao/iOSHardwareDecoder （解码）
https://github.com/manishganvir/iOS-h264Hw-Toolbox （编码）
This demo use Video Toolbox to encode/decode H264 video stream.
Compressing into H264,and decompress for CVPixelbuffer ,using OpenGL to display. The video source come from camera. Recommending use landscape mode for this demo.(I do it on my ipad :)
1.Tap "start" button to begin capture video and decode video stream into H.264 format and save a file named:"test.h264"(file stream, raw H.264. Or you can save it as "xxx.mov""xxx.txt" whatever you want) in sanbox at the same time;
2.Tap "stop" button for stop capturing and stop encoding;
3.Tap "play" button to replay the video you just record in sanbox(decode H.264 stream).
4.Tap "Stop" button to stop decode.
You can get that file(test.h264) after those steps from iTunes:device->"thisDemo"->file shareing. Change the file subffix to ".mov". Drag into MPlayerX can play.
Refred: