[FFmpeg-devel] [PATCH] MOV YUV2 fourcc -> PIX_FMT_YUYV422 mapping

[Jai Menon]

On 3/26/09, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Wed, Mar 25, 2009 at 08:47:33AM -0700, Baptiste Coudurier wrote:
>  > On 3/25/2009 8:35 AM, Reimar D?ffinger wrote:
>  > > On Wed, Mar 25, 2009 at 03:01:50PM +0100, Michael Niedermayer wrote:
>  > >> On Wed, Mar 25, 2009 at 09:48:51AM +0530, Jai Menon wrote:
>  > >>> Index: libavcodec/rawdec.c
>  > >>> ===================================================================
>  > >>> --- libavcodec/rawdec.c   (revision 17944)
>  > >>> +++ libavcodec/rawdec.c   (working copy)
>  > >>> @@ -144,6 +144,13 @@
>  > >>>          picture->data[2] = tmp;
>  > >>>      }
>  > >>>
>  > >>> +    if(avctx->codec_tag == MKTAG('y', 'u', 'v', '2')) {
>  > >>> +        int i;
>  > >>> +        for(i=1; i<picture->linesize[0]*avctx->height; i+=2) {
>  > >>> +            picture->data[0][i] ^= 128;
>  > >>> +        }
>  > >>> +    }
>  > >>> +
>  > >>>      *data_size = sizeof(AVPicture);
>  > >>>      return buf_size;
>  > >>>  }
>  > >> uhm, apple messed up again?
>  > >> anyway, if this is how its stored in mov this hack (assuminh baptiste agrees)
>  > >> should be in mov.c
>  > >
>  > > yuv2 (not yv12 oder yuy2, I don't think the fourcc conflicts with any other format)
>  > > is a special format that uses signed chroma, seems to be used by some cameras.
>  > > Not sure if it's worth adding a pixfmt for it, but it would be a
>  > > possibility.
>  > > Personally I would consider rawdec an acceptable place for that code.
>  >
>  > I agree with Reimar, however I don't mind if this hack is put in mov.c
>
>
> hmm, it stays ugly no matter where it is ...
>  if people prefer rawdec then iam ok but we also need it in rawenc then

I don't quite understand why someone would want to store color data
like this (chroma plane signed). And as Reimar will confirm, the yuv2
fourcc doesn't seem to conflict with anything else seen in the wild.
Are you suggesting adding a similar if case in raw_encode which sets
the sign bit? such a patch will be quite intrusive, especially for a
pixel fmt which most people won't use :)

>  [...]
>
> --
>  Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
>  GMX, the mailprovider that uses RBL lists to reject mails from your friends
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And hence I shifted to gmail :)

[...]

-- 
Regards,

Jai