参考
iOS原生API 音/视频录制 编辑
https://www.cnblogs.com/kenshincui/p/4186022.html#summary
iOS视频编解码常用库比较
http://blog.csdn.net/humiaor/article/details/76651561
基于FFmpeg的移动端例子
http://blog.csdn.net/leixiaohua1020/article/details/47071547
iOS直播app(原理篇)
http://www.cocoachina.com/design/20160831/17444.html