[FFmpeg-devel] Late SEI is not implemented (providing a sample)

[Miguel Borges de Freitas]

Answering my own question here in case someone else stumbles into this, it turns out those streams were completely broken:

- The CC data SEI NAL units were defined after the primary coded picture which violates the H264 standard
- The user data part of SEI was lacking the marker_bits (0xFF) at the end

Both issues were fixed upstream by the Dash industry forum and the public samples regenerated after the report, they work correctly now in ffmpeg.
Cross-reference: https://github.com/Dash-Industry-Forum/dash-live-source-simulator/issues/115