Broken MXF support

[slydiman]

Summary of the bug:

Here is the MXF sample recorded by Canon C300 ​http://slydiman.me/ffmpeg/mxf/test.mxf (60MB)

I used ffmpeg nightly build version 20230507 with libavformat 60.5.100
ffmpeg_2021 is ffmpeg version 20210714 with libavformat 59.4.100

How to reproduce:

ffmpeg -i test.mxf -c:v copy -y video.h264

ffmpeg_2021 -i video.h264 -c:v copy -y test1_ok.mxf
ffmpeg      -i video.h264 -c:v copy -y test2_fail.mxf

[mxf @ 000002e37b40eac0] Unsupported frame rate 1200000/1. Set -strict option to 'unofficial' or lower in order to allow it!
[out#0/mxf @ 000002e37b409900] Could not write header (incorrect codec parameters ?): Invalid argument
Invalid argument

ffmpeg -r 25 -i video.h264 -c:v copy -y test3_ok.mxf

ffmpeg -i test.mxf -c:v copy -an -y video.mp4

ffmpeg -i video.mp4 -c:v copy -y test4_fail.mxf

[mxf @ 0000022e9ad499c0] Unsupported frame rate 12800/1. Set -strict option to 'unofficial' or lower in order to allow it!
[out#0/mxf @ 0000022e9ad49880] Could not write header (incorrect codec parameters ?): Invalid argument
Invalid argument

ffmpeg -r 25 -i video.mp4 -c:v copy -y test5_fail.mxf

[mxf @ 00000246dee3b180] h264 profile not supported
[mxf @ 00000246dee3b180] could not get h264 profile
av_interleaved_write_frame(): Operation not permitted
[out#0/mxf @ 00000246dceb9400] Error muxing a packet
[out#0/mxf @ 00000246dceb9400] Error writing trailer: Unknown error occurred
[out#0/mxf @ 00000246dceb9400] video:1878kB audio:0kB subtitle:0kB other streams:0kB global headers:10kB muxing overhead: unknown

[Balling]

As was mentioned [1], mxf is asking for Annex B. It does not support normal AVC. Partially fixed here, but of course some work left 64634e809f2e7b6c1a1ea3f6952a17c5915c3f22

[1] ​https://patchwork.ffmpeg.org/project/ffmpeg/patch/AM7PR03MB66600B2742E305A97C277D898F929@AM7PR03MB6660.eurprd03.prod.outlook.com/