[Ffmpeg-devel] Re: integrating AVS decoding into MPlayer

[Baptiste Coudurier]

Rich Felker wrote:
>> [...]
>>
>> And why not specifying BEST wraping method for codecs instead of using
>> AVI one ?
> 
> We don't specify the AVI one. If there are global headers for the
> codec they are required to be stored globally in NUT, not repeatedly
> attached to every keyframe or whatever other broken formats the codec
> allows.

How to deal with H264 here ? You need to specify something. It is stored
with global headers in MOV and not in AVI. A choice is needed, then a
standard, or do you plan to identify wraping differently ?

> [...]
> 
> Care to explain how these rules will cease to apply?

Like they changed in those years, when compression appeared, then VBR,
who knows...

NUT system is the best one around. Still I persist to say that wraping
specs are needed, and even more for ambiguous codecs wraping formats,
and a fourcc for each codec recognized must be written in the specs,
that means standardized.

>> (And of course you
>> can't be sure that every codec in this world will be wraped correctly in
>> NUT).
> 
> Some nonsense things cannot be, but they won't be able to be stored in
> any other existing container either.

DV in AVI exists. DV in MOV also, PS in MOV, who knows...

>> I persist to say that a container SHALL standardize a codec wraping
>> (even just saying "default wraping rule applies" and its fourcc is ...)
>> if it needs to support it. It should just be a matter of one line per
>> codec, as NUT is very generic ;)
> 
> The one line would be the same for every codec so it's pointless.

IMHO not for H264,

> What about timecode ? Subtitles ?

There is no specifications in NUT specs about wraping those kind of
data. A stream type identifier is not sufficient IMHO.

I just read the specs again and I also do not see and decent standard to
pack extradata for specific codec. Just put the MOV atoms in NUT ?

Btw this thread now belongs to NUT devel IMHO.

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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