Subtitle workflows

Add a selectable track

pyffmpegcore subtitles add --video lesson.mp4 --subtitle captions.srt --output lesson-captioned.mp4 --language eng

Extract an embedded track

pyffmpegcore subtitles extract --video lesson-captioned.mp4 --output extracted.srt --stream-index 0

Burn text into video

pyffmpegcore subtitles burn --video lesson.mp4 --subtitle captions.srt --output lesson-burned.mp4

Selectable subtitles can be preserved separately; burned subtitles permanently change video pixels. The FFmpeg build must provide the relevant subtitle decoder/muxer and the subtitles filter for burning. Paths embedded in filter syntax receive separate escaping from normal process arguments.