Re: [LAD] Ardour session archiver (Was: new lossless/lossy audio compressor)

I got 32-bit true lossless j2kaudio transcoding working today. I compared it against wavpack and
wavpack seems far superior in terms of speed and compression for 32-bit floating point data. I
created the test files with audacity, which only uses float values from +1 to -1, so I am not sure
if it actually uses the full 32-bits, but it is still good enough for a meaningful test.

Here are the compressed size % for the worst case that I tested:
32bWN.wav 44.1kHz/32b/10ch
60sec 10 channels of white noise
105840152B
j2kaudio 91.06
wavpack 82.32
tar czf (gzip) 92.29
tar cjf (bz2) 93.24

The full test tables are here:
http://geocities.com/hildstrom/projects/j2kaudio/

Are there any wav/audio programs out there that use the full float range of 3.4e+/-38? It seems to
me that this larger range would use more of the 32 bits.

Thanks. -Greg

--- Marc-Olivier Barre <mobarre@email-addr-hidden> wrote:

> Paul Winkler wrote:
> > On Tue, Jul 31, 2007 at 10:25:34PM +0200, Marc-Olivier Barre wrote:
> >> I been thinking of the same thing... can't ardour handle FLAC files
> >> natively ?
> >
> > Nope.
>
> I only meant natively reading them.
>
> On 8/1/07, Stefan Kost <ensonic@email-addr-hidden-obscura.de> wrote:
> > >> a simple script in <you-name-it> language calling flac to
> > >> to compress the audio and change the session file to match the new
> > >> names should work I think.
> > >>
> > >> Thoughts anyone ?
> > >
> > > That'd be nice but as I said earlier, FLAC can't handle Ardour's wav
> > > files:
> > >
> > > pw@email-addr-hidden sounds $ flac Audio\ 1-1.wav
> > >
> > > flac 1.1.2, Copyright (C) 2000,2001,2002,2003,2004,2005 Josh Coalson
> > > flac comes with ABSOLUTELY NO WARRANTY. This is free software, and
> > > you are
> > > welcome to redistribute it under certain conditions. Type `flac' for
> > > details.
> > >
> > > options: -P 4096 -b 4608 -m -l 8 -q 0 -r 3,3
> > > Audio 1-1.wav: ERROR: unsupported compression type 3
> >
> > Seems that ardor uses WAVE_FORMAT_IEEE_FLOAT and flac can only do pcm.
> > http://flac.sourceforge.net/faq.html#general__samples
> > That make flac not idea for that purpose. If one still wants to do that,
> > gstreamer could do the converion and en/decoding.
>
> Well if FLAC can be read by ardour directly, gstreamer is not such a
> bother... I can include that in my script.
>
> Paul Winkler wrote:
> > > But as pointed out earlier in the thread, wavpack is open source and
> > > it seems to work.
>
> I'll give a try to wavpack too and tell you how things went.
> _________________
> Marc-Olivier Barre.
> _______________________________________________
> Linux-audio-dev mailing list
> Linux-audio-dev@email-addr-hidden
> http://lists.linuxaudio.org/mailman/listinfo.cgi/linux-audio-dev
>

_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/mailman/listinfo.cgi/linux-audio-dev
Received on Thu Aug 2 00:15:02 2007