QDesign Music Codec
The QDesign Music Codec was originally LBpack, by
Dmitry Shmunk. QDesign corporation bought the codec and hired the developer
to create what would become the official audio compression in Apple's
The codec's official name is "RaveSound", according to this press release,
but is commonly called QDesign Codec. It is one of the most agressive encoders
known - meaning it compresses quite well at very low bitrates, but its
aggressiveness introduces too many artifacts at higher bitrates.
The personal version comes with QuickTime Pro and allows encoding at bitrates up
to 48kbps. The professional version allows bitrates up to 128kbps.
Hosted here are a Demo professional plugin for QuickTime Pro that works for 15
days, and MVP - QDesign's attempt to enter the audio library manager market -
that has unlimited encoding of QDMC up to 128kbps. It can also encode MP3
but the encoder quality is terrible.
I am also hosting here an analysis document created by Benjamin Larsson,
describing the first steps in reverse engineering the codec.
Apple has steered away from proprietary codecs like Sorenson Video and
QDesign, and focused on standards (MPEG4). The QDesign codec lost relevance,
and the company was bought by DTS in 2002.
A mirror of the QDesign website can still be checked at archive.org. I also saved locally a mirror of the QDesign
Music Codec Professional Edition product page.
Download: mvppc12.exe - 2.083kB
Interface: Graphical (QuickTime component)
Download: QDMC2_Pro_Demo.exe - 1.327kB
Interface: PDF document
Download: qdmc2.pdf - 309kB
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