flac dev - Jul 2005 - Apple's Core Audio File container format

Hi all,

It hasn't really been publicized much yet, but Apple has a new 
container file format called CAF:

   http://developer.apple.com/documentation/MusicAudio/Reference/CAFSpec/

CAF files current support integer and float PCM formats, A-law,
u-law and a number of others including AAC and Apple's own Apple 
Lossless Audio Codec (alac).

I have already implemented support for what I can (PCM, A-law,
u-law) in a libsndfile pre-release:

    http://www.mega-nerd.com/tmp/libsndfile-1.0.12pre10.tar.gz

and I'm thinking of adding support for FLAC in a CAF container
as well. Is anyone else working on this? If so please let me
know so we can agree on how FLAC should be contained with CAF.

Cheers,
Erik
-- 
+-----------------------------------------------------------+
  Erik de Castro Lopo  nospam@mega-nerd.com (Yes it's valid)
+-----------------------------------------------------------+
"If you are going to SCO to license superior driver technology,
 you need to reevaluate your product."
  -- Comment about SUN and SCO on Linuxtoday.com

On 7/11/05, Erik de Castro Lopo <erikd-flac@mega-nerd.com>
wrote:
> and I'm thinking of adding support for FLAC in a CAF container
> as well. Is anyone else working on this? If so please let me
> know so we can agree on how FLAC should be contained with CAF.
I'm sorry, but what are the advantages to the different containers, or
this container in particular? I mean this is nothing different than
flac/OggFlac, which are little to none from what I've read (around
hydrogenaudio), am I wrong?

thanks,
avuton
-- 
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.

Avuton Olrich wrote:
> I'm sorry, but what are the advantages to the different containers, or
> this container in particular? I mean this is nothing different than
> flac/OggFlac,
The nice thing is that this single container format can hold audio
data in a number of different encodings. This is also true for
Ogg, but I don't think its true for the FLAC container format.
> which are little to none from what I've read (around hydrogenaudio),
Do you have a link? I googled but couldn't find anything.

Erik
-- 
+-----------------------------------------------------------+
  Erik de Castro Lopo  nospam@mega-nerd.com (Yes it's valid)
+-----------------------------------------------------------+
"I'd crawl over an acre of 'Visual This++' and 'Integrated 
Development That' to get to gcc, Emacs, and gdb.  Thank you."
-- Vance Petree

Avuton Olrich wrote:
> On 7/11/05, Erik de Castro Lopo <erikd-flac@mega-nerd.com> wrote:
> 
>>and I'm thinking of adding support for FLAC in a CAF container
>>as well. Is anyone else working on this? If so please let me
>>know so we can agree on how FLAC should be contained with CAF.
> 
> 
> I'm sorry, but what are the advantages to the different containers, or
> this container in particular? I mean this is nothing different than
> flac/OggFlac, which are little to none from what I've read (around
> hydrogenaudio), am I wrong?
the first thing that comes to mind is the channel layout capabilities of
CAF, it's more advanced than Ogg or Flac.

http://developer.apple.com/documentation/MusicAudio/Reference/CAFSpec/CAF_spec/chapter_3_section_5.html

is there any other format that can properly tag an audio file as an
ambisonics 1st order file?

i havn't looked into CAF before, it looks promising.

my question is: if you put Flac in a CAF container, it's not playable
with any FLAC compatible player. FLAC is also a lossless format, which
means you can recode it. this would be a good time to fix design
"errors" (if there are any) in Flac for CAF/Flac.

btw, do you also want to put wavpack into the CAF container? (to Erik)