This is a fast C implementation of Arturo Camacho's SWIPE' pitch extraction algorithm. See the project homepage for more about the advantages of the SWIPE' algorithm. swipe-1.0.tar.gz contains the current source, which should compile quite neatly.
...Purpose is to buid an MP3 player with the lowest possible cost. Works on mono files (going stereo shouldn't be very complicated). Doesn't use Helix. The huffman decoding uses a clustering based algorithm.