A couple of forum posts at hydrogenaudio.org caught my eye.

Would these developments make MPC playback on the empeg/karma easier to implement?

http://www.hydrogenaudio.org/index.php?showtopic=4094&hl=

http://www.hydrogenaudio.org/index.php?showtopic=12153&hl=

Follow the links and you'll find.... no souce code.

Looks like the files will be mirrored soon at http://rarewares.hydrogenaudio.org/... we'll see...

That's great! What is it?

Peter

The source code is now up at http://rarewares.hydrogenaudio.org/mpc.html

This is supposedly an open-source MPC decoder for the ARM chip. I'm wondering if this source code makes empeg/karma support easy to do, or if ogg support is the only upcoming format for the empeg.

I haven't encoded any MPC files yet, except for test ones, and the benefits of MPC are:

1) Extremely high quality audio (Suitable for archiving and transcoding if lossless is not an option)
2) Very fast encoding time
3) More efficient bitrate usage: MPC has a lower bitrate than MP3s with comparable audio quality. (BTW MPC is VBR only)

The main problems with MPC are very low harware acceptance. Currently, I don't think there are any hardware players! Since I listen to all my music on the empeg (car/living room) or computer (bedroom) I'd make a move towards MPC if there was empeg support. My music would sound a little better, and take up a lot less room. (I'm currently using LAME --alt-preset standard encoded MP3s)

Hope this source code helps out somehow!

-Steve

Depends on the licensing really, just because it's open source doesn't mean much. The code on the site doesn't mention anything apart from it's copyright "START GROUP"
A little before the Tremor codec was released for free, me and a few others on here managed to get a free license given to the empeg team for use with the empeg car. It wasn't really viable however as it still required a lot of legal work to get the contracts and licensing details sorted out. It was the release of the Tremor code under it's current license that really made it possible to be used.

I haven't encoded any MPC files yet, except for test ones, and the benefits of MPC are:

1) Extremely high quality audio (Suitable for archiving and transcoding if lossless is not an option)
2) Very fast encoding time
3) More efficient bitrate usage: MPC has a lower bitrate than MP3s with comparable audio quality. (BTW MPC is VBR only)

If it's based on MP3, it seems likely that it uses techniques covered by the MP3 patents; if so, and bearing in mind that the patent holders would rather people wanting an upgrade from MP3 chose MP3Pro, it seems very unlikely that this will ever become licensable for the car-player. All the BSD source code in the world won't help that; if anyone's interested in MPC support on the car-player, they'll need to approach their country's legislature to get software patents ruled invalid first.

Otherwise, use Vorbis; it shares at least advantages 1 and 3. Or FLAC.

Peter

If it's based on MP3, it seems likely that it uses techniques covered by the MP3 patents; if so, and bearing in mind that the patent holders would rather people wanting an upgrade from MP3 chose MP3Pro, it seems very unlikely that this will ever become licensable for the car-player.

I remember Rob saying at the meet, that, because Rio has already paid Thomson/Frauenhofer for using an MP3 decoder, Rio could use any codec that is covered by their patents.

Perhaps I misunderstood?

Pim

I remember Rob saying at the meet, that, because Rio has already paid Thomson/Frauenhofer for using an MP3 decoder, Rio could use any codec that is covered by their patents.

Yep in theory. That's why we're not worried about including Ogg Vorbis - but an Off Vorbis *only* player which has not paid a patent should be a cause for worry.

Rob

Off Vorbis

Is that anything like Off Broadway?