FFmpeg startcode analysis
The starting code is divided into two types: 0x00 00 01 and 0x00 00 01
There is no start code in the code stream transmitted through rtp. It is necessary to add the start code manually and complete it into a complete NAL video unit before a complete image can be parsed.
It is found that the starting code of H264 stream is 0x00 0001, while that of H265 stream is 0x00 0001, and there is no starting code for audio stream.
