by Hans Verkuil

[permalink] [raw]

Subject: Re: [PATCH v4 05/10] media: Add BGR48_12 video format

On 14/03/2023 11:08, Ming Qian wrote:
> BGR48_12 is a reversed RGB format with 12 bits per component like BGR24,
> expanded to 16bits.
> Data in the 12 high bits, zeros in the 4 low bits,
> arranged in little endian order.
>
> Signed-off-by: Ming Qian <[email protected]>
> ---
> .../userspace-api/media/v4l/pixfmt-rgb.rst | 33 +++++++++++++++++++
> drivers/media/v4l2-core/v4l2-common.c | 1 +
> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
> include/uapi/linux/videodev2.h | 3 ++
> 4 files changed, 38 insertions(+)
>
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst b/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
> index d330aeb4d3eb..fc98a10991f1 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
> @@ -956,6 +956,39 @@ number of bits for each component.
>
> \endgroup
>
> +12 Bits Per Component
> +==============================
> +
> +These formats store an RGB triplet in six or eighth bytes, with 12 bits per component.

eighth -> eight

> +expand the bits per component to 16 bits, data in the high bits, zeros in the low bits,

expand -> Expand

> +arranged in little endian order.
> +
> +.. raw:: latex
> +
> + \small
> +
> +.. flat-table:: RGB Formats With 12 Bits Per Component
> + :header-rows: 1
> +
> + * - Identifier
> + - Code
> + - Byte 1-0
> + - Byte 3-2
> + - Byte 5-4
> + - Byte 7-6
> + * .. _V4L2-PIX-FMT-BGR48-12:
> +
> + - ``V4L2_PIX_FMT_BGR48_12``
> + - 'B312'
> +
> + - B\ :sub:`15-4`
> + - G\ :sub:`15-4`
> + - R\ :sub:`15-4`
> + -
> +
> +.. raw:: latex
> +
> + \normalsize
>
> Deprecated RGB Formats
> ======================
> diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
> index da313a0637de..16d3c91c7da2 100644
> --- a/drivers/media/v4l2-core/v4l2-common.c
> +++ b/drivers/media/v4l2-core/v4l2-common.c
> @@ -252,6 +252,7 @@ const struct v4l2_format_info *v4l2_format_info(u32 format)
> { .format = V4L2_PIX_FMT_RGB565, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
> { .format = V4L2_PIX_FMT_RGB555, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
> { .format = V4L2_PIX_FMT_BGR666, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
> + { .format = V4L2_PIX_FMT_BGR48_12, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
>
> /* YUV packed formats */
> { .format = V4L2_PIX_FMT_YUYV, .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 2, .vdiv = 1 },
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 6543cda5815f..6d9599391d7b 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1302,6 +1302,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_PIX_FMT_RGBX1010102: descr = "32-bit RGBX 10-10-10-2"; break;
> case V4L2_PIX_FMT_RGBA1010102: descr = "32-bit RGBA 10-10-10-2"; break;
> case V4L2_PIX_FMT_ARGB2101010: descr = "32-bit ARGB 2-10-10-10"; break;
> + case V4L2_PIX_FMT_BGR48_12: descr = "12-bit Depth BGR"; break;
> case V4L2_PIX_FMT_GREY: descr = "8-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y4: descr = "4-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y6: descr = "6-bit Greyscale"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 8a6430bc4a00..3c5acd72606c 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -580,6 +580,9 @@ struct v4l2_pix_format {
> #define V4L2_PIX_FMT_RGBA1010102 v4l2_fourcc('R', 'A', '3', '0') /* 32 RGBA-10-10-10-2 */
> #define V4L2_PIX_FMT_ARGB2101010 v4l2_fourcc('A', 'R', '3', '0') /* 32 ARGB-2-10-10-10 */
>
> +/* RGB formats (6 or 8 bytes per pixel) */
> +#define V4L2_PIX_FMT_BGR48_12 v4l2_fourcc('B', '3', '1', '2') /* 48 BGR 12-bit per component */
> +
> /* Grey formats */
> #define V4L2_PIX_FMT_GREY v4l2_fourcc('G', 'R', 'E', 'Y') /* 8 Greyscale */
> #define V4L2_PIX_FMT_Y4 v4l2_fourcc('Y', '0', '4', ' ') /* 4 Greyscale */

Regards,

Hans