Comparison : 24bit/192KHz/stereo FLAC vs. APE, How can it be ? Options

[foorious]

Hi everybody,

I've just made a small comparison between Monkey's Audio 3.99 (Extra High Compression) and FLAC 1.21 (Compression level 8 ), using 24bit/192KHz/stereo files (the files were generated from a vinyl rip).

Of course I expected APE to perform slightly better than FLAC, like it usually does for 16bit/44KHz/stereo files (2-3%, maybe even 5%)... but I didn't really expect this !



Take a look at all the file sizes : we're talking about 20% difference here ! The total file size is 1,53 Go for APE vs. 1,88 Go for FLAC.

So I don't understand. I'm a genuine FLAC enthusiast (all my files are FLAC), but... how can it be ? Is there something wrong here ? Can we do something to improve all the FLAC file sizes ?

Thanks in advance for your explanation.

[SebastianG]

"[...] but if someone has time to try out sebastian's ideas I would be open to incorporating improvements into the encoder."

"[...] Still, this lattice quantization problem is kind of intriguing. [...]"


Just in case anyone works on this: I sent Josh and Justin some C89 source code. It's able to compute approximations and the actual optimal set of quantized LP coefficients given a desired filter order and LP coefficient accuracy.

edit: Since Josh and Justin might not have enough time at their hands to incorporate this in its current form I'm willing to share the source code with others, too (simplified BSD license).

Cheers,
SG

This post has been edited by SebastianG: Aug 16 2008, 11:32