Laurent,
On Wed, Dec 21, 2011 at 05:32:08, Laurent Pinchart wrote:
> Hi Manju,
>
> On Friday 16 December 2011 14:42:48 Hadli, Manjunath wrote:
> > On Thu, Dec 15, 2011 at 18:30:47, Laurent Pinchart wrote:
> > > On Thursday 15 December 2011 13:24:58 Manjunath Hadli wrote:
> > > > add new macro V4L2_PIX_FMT_SGRBG10ALAW8 to represent Bayer format
> > > > frames compressed by A-LAW alogorithm.
> > > > add V4L2_PIX_FMT_UV8 to represent storage of C (UV interleved) only.
> > > >
> > > > Signed-off-by: Manjunath Hadli <manjunath.hadli@xxxxxx>
> > > > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > > > ---
> > > >
> > > > include/linux/videodev2.h | 6 ++++++
> > > > 1 files changed, 6 insertions(+), 0 deletions(-)
> > >
> > > Could you please also document these formats in
> > > Documentation/DocBook/media/v4l ?
> >
> > I will. Sorry to have missed that out.
> >
> > > > diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
> > > > index 4b752d5..969112d 100644
> > > > --- a/include/linux/videodev2.h
> > > > +++ b/include/linux/videodev2.h
> > > > @@ -338,6 +338,9 @@ struct v4l2_pix_format {
> > > >
> > > > #define V4L2_PIX_FMT_HM12 v4l2_fourcc('H', 'M', '1', '2') /* 8
> > > > YUV
> > > >
> > > > 4:2:0 16x16 macroblocks */ #define V4L2_PIX_FMT_M420
> > > > v4l2_fourcc('M', '4', '2', '0') /* 12 YUV 4:2:0 2 lines y, 1 line
> > > > uv interleaved */
> > > >
> > > > +/* Chrominance formats */
> > > > +#define V4L2_PIX_FMT_UV8 v4l2_fourcc('U', 'V', '8', ' ') /* 8
> > > > UV 4:4 */ +
> > > >
> > > > /* two planes -- one Y, one Cr + Cb interleaved */
> > > > #define V4L2_PIX_FMT_NV12 v4l2_fourcc('N', 'V', '1', '2') /* 12
> > > > Y/CbCr
> > > >
> > > > 4:2:0 */ #define V4L2_PIX_FMT_NV21 v4l2_fourcc('N', 'V', '2', '1')
> > > > /* 12 Y/CrCb 4:2:0 */ @@ -366,6 +369,9 @@ struct v4l2_pix_format
> > > > { #define V4L2_PIX_FMT_SRGGB12 v4l2_fourcc('R', 'G', '1', '2') /*
> > > > 12 RGRG.. GBGB.. */ /* 10bit raw bayer DPCM compressed to 8 bits
> > > > */ #define V4L2_PIX_FMT_SGRBG10DPCM8 v4l2_fourcc('B', 'D', '1',
> > > > '0')
> > > > + /* 10bit raw bayer a-law compressed to 8 bits */ #define
> > > > +V4L2_PIX_FMT_SGRBG10ALAW8 v4l2_fourcc('A', 'L', 'W', '8')
> > > > +
> > >
> > > That's not very future-proof, how would you describe SGBRG10ALAW8
> > > for instance ?
> > >
> > > Maybe it's time to standardize FOURCCs for Bayer new formats. We
> > > have 4 characters, we could start with 'B' to denote Bayer, followed
> > > by one character for the order, one for the compression, and one for
> > > the number of bits.
> >
> > I agree.
> > May be ('B', 'G', 'A', '8') is fine for the above?
>
> We need to describe at last BGGR, GBRG, GRBG and RGGB. We could use 'B', 'g', 'G' and 'R' respectively for the second character. The third character would be 'A' for A-law and 'D' for DPCM, and the fourth character could describe the bus width in bits from 0 to 15 with '0' - '9', 'A' - 'F'. However, I suspect that we will need 16-bit wide busses for raw Bayer at some point, and a 0 width is definitely not useful. We could thus offset the width by some value.
>
> This is just a preliminary idea, I'm open to suggestions.
I think it is a very good suggestion that we can go with.
B : BGGR
g : GBRG
G : GRBG
R : RGGB
and 0-F can signify 1-16.
Thx,
-Manju
>
> > > > /*
> > > >
> > > > * 10bit raw bayer, expanded to 16 bits
> > > > * xxxxrrrrrrrrrrxxxxgggggggggg xxxxggggggggggxxxxbbbbbbbbbb...
>
> --
> Regards,
>
> Laurent Pinchart
>
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
