Musepack
Introduction
Musepack is a lossy audio compression scheme created by Andree Buschmann. It is strongly based on the MPEG-1 Layer-2 (MP2) algorithms. The format doesn't compete well at lower, 'streaming' bitrates such as 32/48/64kbps. This is due to MPC being a subband codec as well as the fact that very little optimization has gone into such low bitrates. As can be seen in various 128kbit/s listening tests (see below), despite the fact that MPC has been optimized little for such bitrates it is in the same class of other modern competitors such as AAC and Ogg Vorbis.
Pros
- Suffers from different "problem cases" than most other formats (less pre-echo)
- Very fast encoding/decoding
- Designed to be very good by default at --standard setting.
- Open source encoder
- Portable playback by Pocket-PCs, Palm OS-based and Windows CE/Windows Mobile-based devices, even Smartphones, see http://tcpmp.corecodec.org
- Portable playback on iRiver h1x0 and Archos Gmini players, see http://www.rockbox.org
- Support & development forum at http://www.Musepack.net
Cons
- Marginal support (yet) on portable players
- No multichannel
- No specification available
- Seeking is imperfect (to be fixed in SV7.5)
- Not streamable
- Can't be cut/edited
- No support for sampling rates above 48khz
Technical details
Supported input formats (SV7)
- channels: 1 or 2
- bit depths: 1 to 32 bit linear PCM
- sample rates: 32kHz, 37.8kHz, 44.1kHz, 48kHz (44.1 and 48 are highly tuned)
- WAV, raw PCM, a lot of lossless compressed audio formats like FLAC, LPAC, APE, OptimFROG, SZIP and Shorten (SHN)
Encoder Functions
Links
User oriented links
- Musepack.net - a general info, news and software site.
- Users' HowTo MPC guide at HydrogenAudio
- Case's page (Winamp plug-ins and more).
- Frank Klemm's official page (out of order now)
- Mirrored at: http://hydrogenaudio.org/musepack/klemm/www.personal.uni-jena.de/~pfk/mpp/
- BetaPlayer, the first Musepack-able player on PocketPCs
Technical links
- Frank Klemm's official page
- MPC at AudioCodingWiki
- libmusepack portable musepack decoding library (in progress)
Listening test involving MPC
- Listening Tests page
- ff123's 128kbit/s group listening test
- ff123's second 128kbit/s group listening test
- rjamorim's 128kbit/s test
Please note that some of these tests, while valid, used versions of the encoders in almost all of the formats tested which have now been superseded. You should make your own decision about the comparative quality of MPC, listening to clips of music in the style you prefer.
Also note that these are tests at low bitrates; an area where MPC is not particularly optimized. The encoder was designed by the author to be transparent at the --standard setting, thus little to no low bitrate tuning has gone into the codec, opposite to that of AAC, Ogg Vorbis, WMA and others which focus more on this region. However, as can be seen in the various listening test pages, MPC competes surprisingly well with the rest of them.