[FFmpeg-devel] [PATCH] Common ACELP code & G.729 [4/7] - G.729 core

Benjamin Larsson banan
Fri Oct 17 23:40:36 CEST 2008

Michael Niedermayer wrote:
> On Fri, Oct 17, 2008 at 11:57:26AM +0200, Benjamin Larsson wrote:
>> Michael Niedermayer wrote:
>>>> 4400 mode is (i assume) Chinese extension of G.729. it is not covered
>>>> by official specification.
>>>> And since i have no samples i can't test it. This is why i put those comment.
>>> What makes you think this format even exists?
>>> Is there any source code for a decoder?
>>> Or a specification?
>>> Or is it mentioned in any manual for any hardware?
>>> Iam just a little curious where this stuff comes from ...
>> This comes from Chinese portable media players capable of recording .act 
>> files(the same players are most likely also able to play .amv files), 
>> the only thing that can play these kind of files is a windows application.
>> http://wiki.multimedia.cx/index.php?title=ACT
> well, thats just our wiki ...
> i was more interrested in the source of these claims.
> We do not have a single 4k4 file and we have just a binary decoder that
> may (or may not) support such files.
> we dont even have a manual that claims that such files are supported or
> even exist ...
> Or to say it differently, what evidence is there that this 4400 mode is
> not just a typo in some chinese - english translation of some manual?

The only thing I have seen was in a manual.

Benjamin Larsson

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