[NUT-devel] [RFC] FourCCs for rawvideo rgb4_byte / bgr4_byte

[Michael Niedermayer]

On Wed, May 26, 2010 at 12:49:54AM +0200, Stefano Sabatini wrote:
> On date Sunday 2010-05-23 04:30:44 +0200, Michael Niedermayer wrote:
> > On Fri, May 21, 2010 at 12:19:10AM +0200, Stefano Sabatini wrote:
> > > Hi all, this follows a thread from ffmpeg-devel:
> > > http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/109054/focus=109394
> > > 
> > > I proposed these names:
> > > B4BY (bgr4_byte) Packed BGR 1:2:1,  8bpp, (msb)1B 2G 1R(lsb)
> > > R4BY (rgb4_byte) Packed RGB 1:2:1,  8bpp, (msb)1R 2G 1B(lsb)
> > > 
> > > Other idea:
> > > bgr4_byte => B[1][2][1]
> > > rgb4_byte => R[1][2][1]
> > > 
> > 
> > > Note that I'm very satisfied with these names, maybe someone can find
> > > a better scheme.
> > > 
> > > What do you think?
> > 
> > i think you are missin a "not" in your sentance
> 
> Yes indeed.
>  
> > and iam not sure abut the fourccs here, this format is simply inefficient
> > to store 4bit rgb, is it used in the wild?
> 
> I have not the faintest idea, and I couldn't even manage to understand
> who introduced it, since it exists since the night of time of FFmpeg.

i probably added it to sws for playing with 4bit dithering


> 
> > if not (its just for ffmpegs test lavfi test system we can just pick any
> > random fourcc and treat it like some ffmpeg internal thing)
> > either of your choices would do for that
> 
> My problem is that I need to *write* such a format in NUT, so I need a
> codec for that. Also to add such a tag shouldn't hurt anyway. If you
> have an idea for avoiding to define a tag for it and still be able to
> store such a format in NUT please tell (well an idea would be to make
> possible to define the codec tag), as for me I prefer to add these two
> rather than add exceptions/special cases to the FFmpeg code.
> 
> Patch updated, regards.

>  nut4cc.txt |    2 ++
>  1 file changed, 2 insertions(+)
> 6e19f1c1d96011a3c5ac6716f91f1040703604bb  add-bgr4-rgb4-byte-codec-tags.patch

ya ok

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

Awnsering whenever a program halts or runs forever is
On a turing machine, in general impossible (turings halting problem).
On any real computer, always possible as a real computer has a finite number
of states N, and will either halt in less than N cycles or never halt.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/nut-devel/attachments/20100526/b691a357/attachment.pgp>