RTP协议是承载在UDP协议之上的应用协议
http://blog.****.net/chen495810242/article/details/39207305
http://blog.51cto.com/692344/1062683
https://www.cnblogs.com/qingquan/archive/2011/07/28/2120440.html
H264 RTP打包rfc文档
https://datatracker.ietf.org/doc/rfc3984/
RTP draft
https://tools.ietf.org/html/rfc3550