Short for MPEG Audio Decoder, MAD is an MPEG audio decoder that has a reputation for excellent sound quality. MAD is fully compliant, having satisfied the ISO/IEC 11172-4 computational accuracy requirements for compliance and so qualifies (in most conditions) as a Full Layer III ISO/IEC 11172-3 audio decoder as defined by the standard. Currently supports MPEG-1, MPEG-2 Lower Sampling Frequencies extension and "MPEG 2.5". All three audio layers (Layer I, Layer II and Layer III) are fully implemented. MAD does not yet support MPEG-2 multichannel audio (though it should be backwardly compatible with those streams) or Advanced Audio Coding (AAC).
Some of MAD's features include:
MAD appears to be quite widely implemented, as the following list of programs containing MAD will show:
Source:
MAD homepage - http://www.mars.org/home/rob/proj/mpeg/