FFmpeg: Convert MKV to MP4 keeping DoVi and subtitles The following FFmpeg command will convert a Dolby Vision (DoVi) enabled Matroska (MKV) file to MPEG-4 Part 14 (MP4) while preserving all subtitles: ffmpeg -i file.mkv -map 0 -c:v copy -c:a copy -c:s mov_text -strict unofficial file.mp4