HydrogenAudio

Lossless Audio Compression => FLAC => Topic started by: BFG on 2012-11-24 02:13:46

Title: Strongest FLAC compression possible?
Post by: BFG on 2012-11-24 02:13:46
Currently, I'm ripping my entire CD collection and compressing into FLACs.  I'm interested in making the FLACs as small as possible and have no concern whatsoever for encoding time.

To achieve this, I'm currently using -V -p -l 12 -b 4096 -m -e -r 8.
(Those who use FLAC regularly will note these settings are even stronger than -8.  I tried using -r 16 which the documentation states is supported, but anything over -r 8 caused an error in my tests.)


My question is: what settings, if any, would allow for even better compression?
Title: Strongest FLAC compression possible?
Post by: saratoga on 2012-11-24 02:17:02
You could try flake, or cudaflac.  They might be able to squeeze a little more compression out.
Title: Strongest FLAC compression possible?
Post by: BFG on 2012-11-24 02:33:31
You could try flake, or cudaflac.  They might be able to squeeze a little more compression out.

Thanks!  I'm not interested in flake since the current version doesn't support metadata (though it'd be great to see the optimizations applied in the reference FLAC).  And it's my understanding that "cuda flac" is a class of Nvidia GPU-based encoders.  If so, is there a specific one you'd recommend?
Title: Strongest FLAC compression possible?
Post by: skamp on 2012-11-24 09:27:38
I'm interested in making the FLACs as small as possible and have no concern whatsoever for encoding time.


FWIW, FLAC -8 is only 0.35% smaller than FLAC -5 on my music collection, and the difference between -8 and your settings is probably going to be a lot smaller than that. It's just not worth it.
Also, see FLACCL (http://www.cuetools.net/wiki/FLACCL).
Title: Strongest FLAC compression possible?
Post by: lvqcl on 2012-11-24 09:41:45
Quote
Also, see FLACCL.

This wiki page is a bit outdated: CUETools 2.1.4 contains FlacCL encoder ver. 0.4.
Title: Strongest FLAC compression possible?
Post by: Porcus on 2012-11-24 10:41:09
The metadata could of course be transferred to flake-encoded files afterwards, if you are a bit handy.

But those who are truly obsessed with compression, should maybe consider other codecs than FLAC, which was optimized for decoding speed. There is really no way to improve over FLAC without sacrificing some degree of compatibility, but if that is no issue, then ... TAK.
Title: Strongest FLAC compression possible?
Post by: IgorC on 2012-12-01 18:08:50
Additional settings "-A tukey(0.5) -A flattop" should bring a bit more compression gain.
http://www.synthetic-soul.co.uk/comparison/lossless/ (http://www.synthetic-soul.co.uk/comparison/lossless/)
Title: Strongest FLAC compression possible?
Post by: BFG on 2012-12-03 17:21:22
Additional settings "-A tukey(0.5) -A flattop" should bring a bit more compression gain.
http://www.synthetic-soul.co.uk/comparison/lossless/ (http://www.synthetic-soul.co.uk/comparison/lossless/)

Thanks for the suggestion.  Not knowing anything about the different -A options, I've left it at default in the past.  I don't suppose you're aware of a website that discusses the different algorithms in depth?
Title: Strongest FLAC compression possible?
Post by: saratoga on 2012-12-03 18:18:13
If this is for portable use, you may want to experiment with lossyflac, as it will remove some of bits wasted storing noise.