ffmpeg, spawned and left to die like ffprobe, maps one subtitle stream
and converts it to SRT under §15's sidecar name. Text formats become
legal translation sources; bitmap tracks never extract.
SubtitleTrack now carries the codec, split text formats from bitmap
ones per DESIGN.md §15, plus the forced and SDH dispositions ffprobe
reports. Without the forced flag a file carrying only a forced track
read as satisfied for that language.
Miguel Palhas
naps62-yolo