Matroska (mka mkv) support

[cameuh]

Hello,

My audio library is consisting of full length albums, each being one single Matroska audio file (mka) where track information are Matroska chapters.

I'm using mplayer to read them (VLC also does).

I searched through the wiki (no result) and the forum (some results indicating such support exists). The documentation's chapter "Supported file formats" doesn't show any matroska format.

Is there a clear support status for this format? Where can we track it?
If it is supported, as I think it is, is the chapter-navigation working?

Thanks,
Camille

[LambdaCalculus]

I moved your thread to Feature Ideas so that we can discuss the possibility of working on Matroska support for Rockbox. Sounds like a pretty nice idea, to begin with.

Anyway, if you're interested, the best thing to do right now is to start reading up on the file format's technical specifications, and looking for a simple, fixed point decoder that we can adapt for use in Rockbox. Since you mentioned that VLC supports MKV/MKA, and VLC is based on ffmpeg, that should be your starting point.

[GodEater]

And in case Lambda's reply doesn't make it clear:

No, it's not currently supported.

[Llorean]

MKV should denote a Matroska Video container, which is not something you should be putting an "album" into anyway. MKA is an audio file, but again it's just a container.

You haven't noted what audio format your files are within the container. Odds are it's a format supported by Rockbox and if you just switch the type of container you're using to the native one for the audio format, you can use your songs without actually re-encoding them.

Matroska is a designed as a universal "container" format. Much like ziploc bags, you can put a lot of things in it, but what's important is what's in it more than the bag itself.

And the closest thing Rockbox has to chapter support is cue sheet support.

[cameuh]

Thanks for your answers

Indeed, I forget to mention my music is Ogg Vorbis because I know it is supported.

The CUE sheet support should be very close to what I'm looking for with matroska chapters, and matroska is supported by the ffmeg library.

If I can find some time for this, putting these pieces together shouldn't be too difficult (note that I'm not a developer and I don't know the Rockbox code).

Best regards,
Camille

[Llorean]

I would suggest you just move the audio into Ogg containers and use cue sheets.

Or better yet, just use separate files since Vorbis is gapless anyway, and doesn't need to be kept in a single file.

Since it's just a container change (and possibly cutting) you should be able to do it without transcoding, as Rockbox is unlikely to ever officially support containers other than the "native" ones for a given format.