Let's say you've got a video file on hand with baked-in subtitles. No matter what you try, your casting software just can't convince ChromeCast to utilize those subs. What's a man to do?
Below is a quick guide to solve this.
MP4Box can extract subtitles reliably. On Arch Linux, it's a binary included in the
gpac package. Before we can extract subtitles, let's analyse our file:
This will highlight all the video, audio, and subtitles "tracks" within the file. If our target subtitle track were "Track 4", then to extract it:
Your subtitles may have been extracted as a pair of files: a
.sub and a
.srt is a more friendly, plain-text format that casting software can handle easier. To convert, use this website.
VLC has decent casting support, but often trips over subtitles. On the other hand, Catt supports these well. With your original
.mp4 file and newly converted
.srt in hand, we can begin casting with: