https://github.com/winlinvip/simple-rtmp-server/issues/66
https://github.com/justinmakaila/iOS-FrameEncoder/blob/master/libRTMPClient.m
https://github.com/winlinvip/simple-rtmp-server/wiki/Edge#hls%E8%BE%B9%E7%BC%98
https://github.com/wenjiegit/Bull-Live-Server