[mythtv-users] Export recordings to matroska or similar multi-stream container?

[spectro]

I want to export my OTA HDTV recordings (from HDHomerun) to a format
that keeps all caption and audio streams in a single file (ABC
broadcasts of Lost with English and Spanish captions for example). I
know that matroska can handle multiple streams and I am planning to
put together a script. Just want to know if there are any such scripts
out already before I go reinventing the wheel. Googling didn't find
anything.