RTPM中H264的VideoTag

Frame TypeUB [4]

Type of video frame. The following values are defined:
1 = key frame (for AVC, a seekable frame)
2 = inter frame (for AVC, a non-seekable frame)
3 = disposable inter frame (H.263 only)
4 = generated key frame (reserved for server use only)
5 = video info/command frame

CodecIDUB [4]

Codec Identifier. The following values are defined:
2 = Sorenson H.263
3 = Screen video
4 = On2 VP6
5 = On2 VP6 with alpha channel
6 = Screen video version 2
7 = AVC

AVCPacketTypeF UI8

The following values are defined:
0 = AVC sequence header
1 = AVC NALU
2 = AVC end of sequence (lower level NALU sequence ender isnot required or supported)

CompositionTimeSI24
IF AVCPacketType == 1
Composition time offset
ELSE
0

在第一个RTMP Message的数据包中,需要发送AVC sequence header, 也就是AVCDecoderConfigurationRecord

其中就包含有Profile / Level / SPS / PPS 等解码需要的信息，然后就开始发送NALU了。