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.
Now, there is something to be said for the convenience aspect here. It's undoubtedly easier to manage a music library where each song appears as a single file, rather than maintaining separate lossless and lossy files for each piece of music. But mp3HD doesn't actually solve the problem that created the need for separate files in the first place: getting music onto a storage-constrained device.
Nearly every portable device currently on the market can support playback of at least one form of lossless compression. The reason that this capacity isn't used is because lossless files take up too much space, meaning that far fewer tracks can be stuffed onto a portable player. mp3HD actually exacerbates this problem. And, unless and until the format is supported by portable players, most devices are going to be playing the lossy, MP3 portion of the file anyway.
The format also doesn't seem to do anything to future-proof Thomson for the time when more portable devices contain enough storage to hold large, lossless libraries. Since it's a simple matter for any device to support both lossless and MP3 playback, the backwards compatibility is essentially meaningless. In fact, the "one file fits all" approach will be a drawback at an intermediate stage, when storage will be sufficient to hold a mix of lossless and lossy tracks.
Thomson may recognize that it has an uphill battle on its hands, as it's giving an encoder away. There are command line versions for Windows and Linux, along with a Winamp plugin. Although the company's site is silent about a Mac version, its Twitter feed says that one will be available soon.
Source: ars technica