[NUT-devel] Re: [Vorbis-dev] minor Vorbis specification amendment proposal

[Michael Niedermayer]

Hi

On Sun, Jul 30, 2006 at 03:41:38AM +0200, Baptiste Coudurier wrote:
> Hi
> 
> Alex Beregszaszi wrote:
> >>> [...]
> >>>
> >>>    Quicktime lacks an unambigous place for a global header so its
> >>>    outside the scope of this document.
> >> we could add mov to the list of supported containers if we define a
> >> chunk for the global header, other codecs have their own codec
> >> specific global header chunks too, maybe "glbl" could be used if its
> >> not taken yet, but i need to look more carefully at the mov/qt spec so
> >> we unambiguosly define and place it
> > 
> > glbl below trak? vmhd/mdhd/smhd/tkhd are leaf
> 
> Humm, IMHO best place is in stsd like every other codec. Decoder

yes


> specific config atom like 'dvrb'. Is MOV fourcc for vorbis defined ?
> I can't find it anywhere. 'vrbs' would be nice.

my post to vorbis-dev/nut-dev contained vrbs and vorbis as 4-cc and n-cc
identifers, not sure if they where lost in alexs rfc conversation ...


> 
> > Will some Quicktime fanatic speak up? Mike?
> > 
> >> about .mp4, that wasnt covered by the quicktime/mov point, it has a
> >> ESDS atom into which a global header can be put, but iam not very
> >> familiar with the mpeg4-systems / iso-mp4 container specs so i didnt
> >> mention it
> > 
> > That ESDS looks HUGE.
> > 
> 
> MP4 specs would require it to be in stsd as 'mp4a' and object type set
> correctly in esds. It seems gpac already does it and uses a object type.
> That object type should be registered to mp4ra.org I think.

and we of course should use the same method/id gpac uses if we mention .mp4
at all

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
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