MAD is a MPEG audio decoder. It currently supports MPEG-1 and the
MPEG-2 extension to Lower Sampling Frequencies, as well as the
so-called MPEG 2.5 format. All three audio layers (Layer I, Layer II,
and Layer III a.k.a. MP3) are implemented.

MAD supports 24-bit PCM output. MAD computes using 100%% fixed-point
(integer) computation, so you can run it without a floating point
unit.