On 14/03/2023 11:08, Ming Qian wrote:
> Y012 is a luma-only formats with 12-bits per pixel,
> 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 <ming.qian@xxxxxxx>
> ---
> .../userspace-api/media/v4l/pixfmt-yuv-luma.rst | 15 +++++++++++++++
> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
> include/uapi/linux/videodev2.h | 1 +
> 3 files changed, 17 insertions(+)
>
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> index 62078a01de76..7888151f2cd4 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> @@ -103,6 +103,17 @@ are often referred to as greyscale formats.
> - ...
> - ...
>
> + * .. _V4L2-PIX-FMT-Y012:
> +
> + - ``V4L2_PIX_FMT_Y012``
> + - 'Y012'
> +
> + - Y'\ :sub:`0`\ [3:0] `0000`
> + - Y'\ :sub:`0`\ [11:4]
> + - ...
> + - ...
> + - ...
> +
> * .. _V4L2-PIX-FMT-Y14:
>
> - ``V4L2_PIX_FMT_Y14``
> @@ -146,3 +157,7 @@ are often referred to as greyscale formats.
> than 16 bits. For example, 10 bits per pixel uses values in the range 0 to
> 1023. For the IPU3_Y10 format 25 pixels are packed into 32 bytes, which
> leaves the 6 most significant bits of the last byte padded with 0.
> +
> + For Y012 and Y12 formats, Y012 place its data in the 12 high bits, with
place -> places
> + padding zeros in the 4 low bits, in contrast to Y12 format, which have
to Y12 -> to the Y12
have -> has
> + its padding located in the most significant bits of the 16 bit word.
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 6489b67babfa..2cb485643562 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1307,6 +1307,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_PIX_FMT_Y6: descr = "6-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y10: descr = "10-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y12: descr = "12-bit Greyscale"; break;
> + case V4L2_PIX_FMT_Y012: descr = "12-bit Greyscale"; break;
I don't really like having two identical pixelformat names, but I can't
think of a good way to describe the difference.
Perhaps "12-bit Greyscale (bits 15-4)"?
Regards,
Hans
> case V4L2_PIX_FMT_Y14: descr = "14-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y16: descr = "16-bit Greyscale"; break;
> case V4L2_PIX_FMT_Y16_BE: descr = "16-bit Greyscale BE"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index f83a9d1210fb..db06d4c4f008 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -586,6 +586,7 @@ struct v4l2_pix_format {
> #define V4L2_PIX_FMT_Y6 v4l2_fourcc('Y', '0', '6', ' ') /* 6 Greyscale */
> #define V4L2_PIX_FMT_Y10 v4l2_fourcc('Y', '1', '0', ' ') /* 10 Greyscale */
> #define V4L2_PIX_FMT_Y12 v4l2_fourcc('Y', '1', '2', ' ') /* 12 Greyscale */
> +#define V4L2_PIX_FMT_Y012 v4l2_fourcc('Y', '0', '1', '2') /* 12 Greyscale */
> #define V4L2_PIX_FMT_Y14 v4l2_fourcc('Y', '1', '4', ' ') /* 14 Greyscale */
> #define V4L2_PIX_FMT_Y16 v4l2_fourcc('Y', '1', '6', ' ') /* 16 Greyscale */
> #define V4L2_PIX_FMT_Y16_BE v4l2_fourcc_be('Y', '1', '6', ' ') /* 16 Greyscale BE */
