[MPlayer-dev-eng] new nut thread

[Roberto Togni]

On 2004.10.08 00:10, D Richard Felker III wrote:
> ok here are the things that have been discussed recently. let's make
> some decisions on the ones still open:
[...]
> 
> 7. removing m$ & apple header support
> 
> proposed by me
> michael agreed, iirc
> seems like a very good idea

Agree, as long as all all the info required to recreate them are  
available in some other header. We need those info to recreate the  
proprietary structures for binary codecs, and some fields are needed  
also by native implementations.

Looks like for video all the infos are available, maybe except for the  
bit per pixel value, unless it can be coded in colorspace_type field  
(some codec ie. qtrle and iirc huffyuv requires it)

For audio we have to check if some codecs need things like sample size  
as input value.


> 8. codec id for raw (uncompressed) formats
> 
> michael and i both agreed each raw format should have a separate id
> i think others agree too
> what remains? making a table of ids

i'm for using a single id (except maybe for yuv formats) and store  
other data in codec_specific_data (like number of bits for rgb  
formats).

Maybe for video we can use colorspace_type, if i didn't misunderstood  
it's meaning, so we don't even need codec data.
If we use a single id for raw audio we need to store at least sample  
size

In this way we don't need to create new id to support new variations.

Bu if you prefer to go with one id per format that's ok too.


> 9. stick with fourcc/twocc system or improve/replace it?-
> 
> i raised the question
> no proposals yet

I'm for sticking with fourcc, i see no advantage in having every  
container defining it's own id for every codec.

twocc are a m$ invention, everything else (quicktime, real, ...) uses  
fourcc for audio too. QT stores m$ data with fourcc "ms##", where ## is  
the twocc, we could do something similar for codecs that don't have any  
other commonly used name.

So my sugestion is: use fourcc for video and for audio (and make them  
case insensitive).

Ciao,
 Roberto