QDesign Music Codec

• FOURCCs: QDMC, QDM2
• Company: QDesign
• Samples: http://samples.mplayerhq.hu/A-codecs/QDMC/ (QDMC)
• Samples: http://samples.mplayerhq.hu/A-codecs/QDM2/ (QDM2)

QDesign Music Codec is a perceptual audio codec commonly used in MOV files between 1998 and 2005, after which it was more or less supplanted by AAC for the same role. Variants of QDM2 with 32, 16 or 8 subbands exist, 16 and 8 decode with noticeable artifacts (metallic sound).

QDMC was the first version of the codec which was apparently short lived and quickly superceded by the second version, QDM2. While QDM2 is supported in open source software (via FFmpeg), QDMC is not supported at all at this point.