[NUT-devel] [PATCH] fourcc spec

[Rich Felker]

On Fri, Apr 14, 2006 at 11:05:20PM +0200, Michael Niedermayer wrote:
> Hi
> 
> On Fri, Apr 14, 2006 at 12:43:36PM +0200, Alex Beregszaszi wrote:
> > Hi,
> > 
> > > length,string
> > > 
> > > Video
> > > 4,"MP4S"	MPEG-4 Part 2
> > > 4,"H264"	MPEG-4 Part 10
> > > 
> > > Audio
> > > 4,"vrbs"	Xiph.org Vorbis
> > > 2,"\x00\x50"	MP3
> > 
> > For gods sake, dont do that mess.
> > 
> > 0050 for mp3..

I agree, random numeric twocc's for audio are an abomination.

> > Also first decide to use all-uppercase or all-lowercase, but dont mix
> 
> agree

On occasion there may be a reason to choose a specific case, but cases
should not be mixed just randomly for the hell of it, for sure.

I would prefer lowercase but it's not a big deal, and if historic
usage is DOS UPPERCASE LAMENESS then perhaps we should just use it.

> > it. And I would just stick to all fourcc (4bytes) for audio aswell. I
> 
> agree

Agree strongly.

> and may i suggest to do mpeg audio/video more consistant?
> 
> mpegX      video "MXV",0 (M1V,M2V,M4V)
> AC3     "AC3",0
> H26X    "H26X"

Looks good. What about h263+? :)

> mp3     "MP3",0

And "MP2",0 "MP1",0 ...?

> and a generic suggestion that the file extension should be used as
> fourcc if theres a well known filename extension for the elementary
> stream
> and generic suggestion 2 if theres a well known avi fourcc then that
> should be used

These seem reasonable.
Can we clarify that the "well known avi fourcc" should refer to the
compression format and not a specific implementation name or marketing
crap?

Rich