MKV / WebM: Subtitle codec not recognized
Subtitles in WebM and MKV files don't work:
title-unknown-Decoder|decoder-application/x-subtitle-unknown (application/x-subtitle-unknown-Decoder)
The subtitles are stored in their own track where CodecID is D_WEBVTT/SUBTITLES
.
Sample file: trailer_400p_subtitle.webm
Sample file info
The sample file is made from https://peach.blender.org/trailer-page/ (trailer_400p.ogg) and the following WebVTT (trailer_400p.vtt):WEBVTT
00:00.000 --> 00:33.000
[Dramatic music throughout but no speaking]
The WebM file was created with ffmpeg:
ffmpeg -i trailer_400p.ogg -i trailer_400p.vtt -map 0 -map 1:0 -metadata:s:s language=en -metadata:s:s title=English trailer_400p_subtitle.webm