spdifenc: Too large TrueHD frame

[Mitzsch01]

Summary of the bug:
Play a high bitrate (11+Mbit) TrueHD track with passthrough enabled, you will experience dropouts.

How to reproduce:
Play a file that contains a TrueHD (with Atmos) track which exceeds a bitrate of approximately 11 Mbits in any FFmpeg based software.
kodi on windows will crash, vlc will "skip" (means you won´t hear something at these parts, continues playback) this part or crash
mpv will "skip" (like vlc) this part but also prints an "error"

Too large TrueHD frame of 2618 bytes is not implemented. 
Update your FFmpeg version to the newest one from Git. 
If the problem still occurs, it means that your file has a feature which has not been implemented.

[Mitzsch01]

I also have a file that produces these issues, but it´s too large (6mb)
Any idea how to submit it?

[Carl Eugen Hoyos]

Use a file hoster of your choice or ​https://streams.videolan.org/upload/

[Mitzsch01]

Thank you!
I´ve uploaded it to the videolan page.
​https://streams.videolan.org/ffmpeg/incoming/truehd_11mbit_bug.mkv

[Carl Eugen Hoyos]

The crashes are imo an independent issue, see ticket #7733, I believe that at least some of the programs you tested do not use FFmpeg for spdif muxing.

Work-around is to use -bsf:a truehd_core, I don't think my receiver allows Atmos substreams at all, at least I was unable to find a muxing strategy that allows playback without stuttering (it is very easy to find a muxing strategy that does not overflow the spdif frame size for the sample you provided). My tests showed that the current strategy can definitely be improved though.

[Carl Eugen Hoyos]

This was fixed by Anssi Hannula in 56df8296f5221524bd06e91e6639c08753d1b8a0 and some earlier commits.