FR: playing audio track from video files (`mkv`, `webm`, `mp4`,...)

[groutoutlook]

Feature request

Right now I have to add them into .mpdignore since it's kept popping up errors as

2026-04-26T15:04:05 ffmpeg/tty: Could not find codec parameters for stream 0 (Video: ansi, none): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
2026-04-26T15:04:05 ffmpeg: Unsupported libavcodec SampleFormat value: name   depth (?)
2026-04-26T15:04:05 update: added music.backup.highres/Accendio.mkv
....
2026-04-26T16:44:00 ffmpeg/tty: Could not find codec parameters for stream 0 (Video: ansi, none): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
2026-04-26T16:44:00 ffmpeg: Unsupported libavcodec SampleFormat value: name   depth (?)
2026-04-26T16:44:00 update: added music.backup.highres/Billionare.webm

I want to avoid another duplicate of those files (as detach/re-encode audio files out of video files, that will work)... so can we support my use case by just take the video's audio track and somehow select just audio channel instead?

[groutoutlook]

Actually for certain kind of media files we cant do that since it's tightly packed with video data.
Rather than that, just duplicate another audio track, mkv and webm actually does support that, and it works with current ffmpeg decoder.

> ffmpeg -i .\Accendio.mkv  -map 0:v -c:v copy -map 0:a -c:a copy -map 0:a -strict -2 -c:a aac .\Accendio-multi.mkv