[Flac-dev] Why so many lossless formats?

[Brian Willoughby]

Hi folks,

I'm trying to get a handle on the many lossless audio formats from the  
perspective of a software developer.  I love the FLAC format because it is open  
source and it performs very well.  But there is also the MLP (Meridian  
Lossless Packing), AAC (Apple Lossless), and probably some Microsoft format(s)  
that compete in the same feature set.  These formats all achieve approximately  
2:1 compression without loss of detail.

What I would like to know is where to go to find out the details on these  
formats.  Is MLP documented anywhere?  It has been accepted as an audio format  
for DVD-HD, so does that mean it must be openly documented?  Dolby Digital AC-3  
is documented as part of the HDTV specification, but it cannot be implemented  
without paying licensing.  Well, a programmer could implement it based on the  
specification, but could not make a product without licensing.

Also, what about Apple's Lossless format?  Is this part of a larger  
specification, like MPEG-4, or is it completely independent?  Is it documented  
anywhere?

Sorry for the non-FLAC questions.  Basically, because FLAC is open source, all  
of these questions are unnecessary for FLAC.  I just want to put the other  
competing formats into perspective, and learn more about them if possible.

Brian Willoughby
Sound Consulting