Musepack

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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

MPC Encoder Functions


Links

User oriented links

Technical links

Listening test involving MPC

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some of these tests, while valid, used versions of the encoders in almost all of the formats tested which have now been superseded.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.