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anon
27.03.09, 20:28
It's a measure of success that the term "MP3" is probably generally understood to mean "digital audio file." But an MP3 file contains a very specific type of audio compression, and its success, in part, comes from its flexibility. As disk space (and, subsequently, flash memory space) has become less constrained, lighter compression could be used to produce better audio quality, even if it meant larger files. The inevitable end of the game will come when portable devices have the ability to hold complete music files in a lossless format. Thomson, one of the companies that developed the MP3 format, has prepared for that day, and is now releasing what it's terming a backwards-compatible lossless format, mp3HD.

Thomson is somewhat vague on the details of the file format, but it appears to have separate streams or forks. One contains a lossless version of the music, which Thomson describes as "additional side information." The other portion contains standard MP3 music data. The idea is that when a player that isn't aware of mp3HD encounters the file, it will pick out and play the MP3 portion. Anything that has been updated to handle the new format will play the full, lossless glory encoded in the alternate data stream.

The problem here is that, as a certain fictional character would put it, Thomson cannot change the laws of physics. Music can only be compressed so far and still retain the label lossless, and other, competing formats appear to be close to those limits. Meanwhile, a high-quality MP3 file also requires a decent amount of space. Put them together in the same file, and you will inevitably get a file that's even larger than anything a lossless encoder would produce. That's exactly what CNET UK found when it took Thomson's mp3HD encoder for a test drive.

Article (http://arstechnica.com/media/news/2009/03/new-lossless-mp3hd-format-trades-convenience-for-file-size.ars)
Codec (http://www.all4mp3.com/Learn_mp3_hd_1.aspx)