Audio Codec : QDesign

QDesign is a music codec, originally known as LBpack, by Dmitry Shmunk. QDesign corporation bought the codec and hired the developer to create what would become the official audio compression inApple Computer's QuickTime v3.

The codec's official name is "RaveSound",^[1] but is commonly called QDesign Codec. It is optimized to compress quite well at very low bitrates, but its aggressiveness introduces audible artifacts at higher bitrates.

The personal version comes with QuickTime Pro and allows encoding at bitrates up to 48 kbit/s. The professional version allows bitrates up to 128 kbit/s.

Apple is now steering away from proprietary codecs in QuickTime like Sorenson Video and QDesign, and focusing on standards (MPEG-4). In recent years, usage of QDMC has generally been eschewed in favor of AAC.

 

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