[Flac] Exact metadata reproduction

[Bryan Ford]

Hi!  I'm just now preparing the first, still very experimental (way pre-1.0) 
release of a new archival tool, similar to (and based on) zip/unzip, with the 
difference that the enhanced zip tool can store x86-based decompressor code 
fragments in archives along with the compressed data, which the unzip tool 
runs in an isolated user-mode virtual machine in order to extract the data.  
The main benefit is that the archiver can upgrade or adapt its compression 
algorithms to different file types without further changing the basic archive 
format or breaking compatibility with existing tools.  The new tools and the 
virtual machine they are based on are more fully described in this paper (to 
appear in USENIX File and Storage Technologies next month):

	http://www.brynosaurus.com/pub/os/vxa.pdf
	http://www.brynosaurus.com/pub/os/vxa/ (HTML version)

I've already integrated FLAC as an example media-type-specific compressor that 
the archiver can use automatically on WAV files it runs across, rather than 
futilely trying to run them through gzip or another general-purpose 
algorithm.  It works, and everything's peachy, except for the minor problem 
that FLAC is currently only lossless at the audio data level and not at the 
file level.  I see that this issue has already been discussed on this list 
and is in the FAQ, and for the current typical uses of FLAC I don't see its 
current behavior as a problem.  But to work as a component of a 
general-purpose archiver that's supposed to (by default anyway) reproduce the 
files it archives _exactly_, we really need exact metadata replication for 
whatever uncompressed audio formats it supports (certainly WAV, ideally 8SVX 
too).

So, my question: has anyone done work on adding exact metadata replication 
support to FLAC, or is it currently planned or on the horizon?

Thanks!
Bryan