row-mp3

row-mp3 is a perceptual audio codec developed by Colin Raffel, Jieun Oh, and Isaac Wang. It is backwards-compatible with the mp3 (that is, it will play in any mp3 player) but offers higher perceived audio quality at a low file size cost for players that support the format. It works by storing perceptually coded information about the MP3 coding error in the MP3's ID3 tags. It is based on early work on using noise substitution for backwards-compatible audio codec improvement. Lots more information can be found in this write-up, and if you're interested in hearing how it sounds and comparing it to lossless files and a normal mp3, please click here. The source is available on the Google Code page.