Flac - Sep 2004 - [Flac-users] Re: settings for tighter compression than -8?

If processing time is not a big factor -- say, I could put up with four 
to six times the duration of compressing at -8 -- what command-line 
settings could one use to get even more compression?

I have a case where the FLACs encoded at -8 are about 653.3 MB, but the 
set comes with artwork whose jpegs are 50.5 MB (I tried zipping the 
jpegs, realizing it would do very little, and the zip file still came to 
50.1 MB).  Any hope of squeezing the FLAC files a little more to get the 
total down to 703.12 MB to fit onto a CDR?  My hardware doesn't support 
overburning, and I don't want to cut the resolution of the jpegs.

Thanks for any assistance.

Miroslav Lichvar wrote:

 > Ok, you need 0.04% improvement, that should not be a problem.

Perhaps a little more than that, since the sizes I listed were after 
stripping out the padding and all metadata blocks except SEEKTABLE and 
STREAMINFO.

 > Try flac --lax -e -p -l 32 -r 10 --no-padding
 > and if it is not enough, increase -r up to 16.

Thank you.  I'll do that.  What, though, are the "non-Subset
files" that
the description of the --lax option allows?

Early this past week, Miroslav Lichvar suggested for me:
> Ok, you need 0.04% improvement, that should not be a problem. Try
> flac --lax -e -p -l 32 -r 10 --no-padding
Thank you again, Miroslav.  I tried that, and it took almost two full 
days (surprisingly, Windows ME stayed up that long without crashing) to 
re-encode the entire set on my 266-MHz machine.  After all, in the help 
file Josh gives us fair warning that a couple of those options are slow. 
  But thirty-eight of the forty-six tracks came out larger than they had 
in my original attempt at the -8 preset (both groups were compared after 
stripping all metadata and padding except STREAMINFO and SEEKTABLE).

When I took the smaller version of each track, the total was still too 
big for a CDR without overburning -- by apparently less than 10 KB, but 
still too big.

Miroslav concluded,
> and if it is not enough, increase -r up to 16.
... so I tried -r 16 on the eight tracks that had benefited before.  All 
of the first four came out larger at -r 16 than at -r 10, and the 
detailed help display from flac --explain says that setting -r "above 4 
usually doesn't help much," so I stopped the process there.

In the end, I tried zipping the original .flac files done at -8, and 
although about sixteen (or fourteen?) of them came out larger, the total 
decreased enough to fit the music and .jpegs onto one CDR.  I tried 
removing the ones that had increased from the .zip archive, but neither 
Explorer nor WinZip could manage that without hanging.  Then I was going 
to write down which ones got larger from zipping and re-zip the others 
without them, but in the end I figured it wasn't worth the trouble to 
keep track of which ones belonged in the .zip archive and which didn't. 
  As long as the data fit onto one disc, that was good enough.

On Sun, Apr 06, 2003 at 04:40:42PM -0500, David W. Tamkin
wrote:
> If processing time is not a big factor -- say, I could put up with four 
> to six times the duration of compressing at -8 -- what command-line 
> settings could one use to get even more compression?
> 
> I have a case where the FLACs encoded at -8 are about 653.3 MB, but the 
> set comes with artwork whose jpegs are 50.5 MB (I tried zipping the 
> jpegs, realizing it would do very little, and the zip file still came to 
> 50.1 MB).  Any hope of squeezing the FLAC files a little more to get the 
> total down to 703.12 MB to fit onto a CDR?  My hardware doesn't support
> overburning, and I don't want to cut the resolution of the jpegs.
Ok, you need 0.04% improvement, that should not be a problem. Try
flac --lax -e -p -l 32 -r 10 --no-padding
and if it is not enough, increase -r up to 16.

-- 
Miroslav Lichvar