RE: [EXT] Re: [PATCH 01/10] media: Add P012 and P012M video format

From: Ming Qian
Date: Mon Jan 30 2023 - 03:16:43 EST


>From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
>Sent: 2023年1月27日 22:32
>To: Ming Qian <ming.qian@xxxxxxx>; mchehab@xxxxxxxxxx; Mirela Rabulea
>(OSS) <mirela.rabulea@xxxxxxxxxxx>
>Cc: shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
>festevam@xxxxxxxxx; X.H. Bao <xiahong.bao@xxxxxxx>; dl-linux-imx <linux-
>imx@xxxxxxx>; linux-media@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
>devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>Subject: [EXT] Re: [PATCH 01/10] media: Add P012 and P012M video format
>
>Caution: EXT Email
>
>On 20/12/2022 04:11, Ming Qian wrote:
>> P012 is a YUV format with 12-bits per component with interleaved UV,
>> like NV12, expanded to 16 bits.
>> Data in the 12 high bits, zeros in the 4 low bits, arranged in little
>> endian order.
>> And P012M has two non contiguous planes.
>>
>> Signed-off-by: Ming Qian <ming.qian@xxxxxxx>
>> ---
>> .../media/v4l/pixfmt-yuv-planar.rst | 94 +++++++++++++++++++
>> drivers/media/v4l2-core/v4l2-common.c | 2 +
>> drivers/media/v4l2-core/v4l2-ioctl.c | 2 +
>> include/uapi/linux/videodev2.h | 2 +
>> 4 files changed, 100 insertions(+)
>>
>> diff --git
>> a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
>> b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
>> index f1d5bb7b806d..aa37c3de8808 100644
>> --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
>> +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-planar.rst
>> @@ -123,6 +123,20 @@ All components are stored with the same number
>of bits per component.
>> - Cb, Cr
>> - Yes
>> - 4x4 tiles
>> + * - V4L2_PIX_FMT_P012
>> + - 'P012'
>> + - 12
>> + - 4:2:0
>> + - Cb, Cr
>> + - Yes
>> + - Linear
>> + * - V4L2_PIX_FMT_P012M
>> + - 'PM12'
>> + - 12
>> + - 4:2:0
>> + - Cb, Cr
>> + - Yes
>> + - Linear
>> * - V4L2_PIX_FMT_NV16
>> - 'NV16'
>> - 8
>> @@ -586,6 +600,86 @@ Data in the 10 high bits, zeros in the 6 low bits,
>arranged in little endian ord
>> - Cb\ :sub:`11`
>> - Cr\ :sub:`11`
>>
>> +.. _V4L2-PIX-FMT-P012:
>> +.. _V4L2-PIX-FMT-P012M:
>> +
>> +P012 and P012M
>> +--------------
>> +
>> +P012 is like NV12 with 12 bits per component, expanded to 16 bits.
>> +Data in the 12 high bits, zeros in the 4 low bits, arranged in little endian
>order.
>> +
>> +.. flat-table:: Sample 4x4 P012 Image
>> + :header-rows: 0
>> + :stub-columns: 0
>> +
>> + * - start + 0:
>> + - Y'\ :sub:`00`
>> + - Y'\ :sub:`01`
>> + - Y'\ :sub:`02`
>> + - Y'\ :sub:`03`
>> + * - start + 8:
>> + - Y'\ :sub:`10`
>> + - Y'\ :sub:`11`
>> + - Y'\ :sub:`12`
>> + - Y'\ :sub:`13`
>> + * - start + 16:
>> + - Y'\ :sub:`20`
>> + - Y'\ :sub:`21`
>> + - Y'\ :sub:`22`
>> + - Y'\ :sub:`23`
>> + * - start + 24:
>> + - Y'\ :sub:`30`
>> + - Y'\ :sub:`31`
>> + - Y'\ :sub:`32`
>> + - Y'\ :sub:`33`
>> + * - start + 32:
>> + - Cb\ :sub:`00`
>> + - Cr\ :sub:`00`
>> + - Cb\ :sub:`01`
>> + - Cr\ :sub:`01`
>> + * - start + 40:
>> + - Cb\ :sub:`10`
>> + - Cr\ :sub:`10`
>> + - Cb\ :sub:`11`
>> + - Cr\ :sub:`11`
>> +
>> +.. flat-table:: Sample 4x4 P012M Image
>> + :header-rows: 0
>> + :stub-columns: 0
>> +
>> + * - start0 + 0:
>> + - Y'\ :sub:`00`
>> + - Y'\ :sub:`01`
>> + - Y'\ :sub:`02`
>> + - Y'\ :sub:`03`
>> + * - start0 + 8:
>> + - Y'\ :sub:`10`
>> + - Y'\ :sub:`11`
>> + - Y'\ :sub:`12`
>> + - Y'\ :sub:`13`
>> + * - start0 + 16:
>> + - Y'\ :sub:`20`
>> + - Y'\ :sub:`21`
>> + - Y'\ :sub:`22`
>> + - Y'\ :sub:`23`
>> + * - start0 + 24:
>> + - Y'\ :sub:`30`
>> + - Y'\ :sub:`31`
>> + - Y'\ :sub:`32`
>> + - Y'\ :sub:`33`
>> + * -
>> + * - start1 + 0:
>> + - Cb\ :sub:`00`
>> + - Cr\ :sub:`00`
>> + - Cb\ :sub:`01`
>> + - Cr\ :sub:`01`
>> + * - start1 + 8:
>> + - Cb\ :sub:`10`
>> + - Cr\ :sub:`10`
>> + - Cb\ :sub:`11`
>> + - Cr\ :sub:`11`
>> +
>>
>> Fully Planar YUV Formats
>> ========================
>> diff --git a/drivers/media/v4l2-core/v4l2-common.c
>> b/drivers/media/v4l2-core/v4l2-common.c
>> index 40f56e044640..a5e8ba370d33 100644
>> --- a/drivers/media/v4l2-core/v4l2-common.c
>> +++ b/drivers/media/v4l2-core/v4l2-common.c
>> @@ -267,6 +267,7 @@ const struct v4l2_format_info
>*v4l2_format_info(u32 format)
>> { .format = V4L2_PIX_FMT_NV24, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 1, 2, 0,
>0 }, .hdiv = 1, .vdiv = 1 },
>> { .format = V4L2_PIX_FMT_NV42, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 1, 2, 0,
>0 }, .hdiv = 1, .vdiv = 1 },
>> { .format = V4L2_PIX_FMT_P010, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 2, 2, 0,
>0 }, .hdiv = 2, .vdiv = 1 },
>> + { .format = V4L2_PIX_FMT_P012, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 2, 4, 0,
>0 }, .hdiv = 2, .vdiv = 2 },
>>
>> { .format = V4L2_PIX_FMT_YUV410, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 3, .bpp = { 1, 1, 1,
>0 }, .hdiv = 4, .vdiv = 4 },
>> { .format = V4L2_PIX_FMT_YVU410, .pixel_enc =
>> V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 3, .bpp = { 1, 1, 1,
>0 }, .hdiv = 4, .vdiv = 4 }, @@ -292,6 +293,7 @@ const struct v4l2_format_info
>*v4l2_format_info(u32 format)
>> { .format = V4L2_PIX_FMT_NV21M, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 2, .comp_planes = 2, .bpp = { 1, 2, 0,
>0 }, .hdiv = 2, .vdiv = 2 },
>> { .format = V4L2_PIX_FMT_NV16M, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 2, .comp_planes = 2, .bpp = { 1, 2, 0,
>0 }, .hdiv = 2, .vdiv = 1 },
>> { .format = V4L2_PIX_FMT_NV61M, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 2, .comp_planes = 2, .bpp = { 1, 2, 0,
>0 }, .hdiv = 2, .vdiv = 1 },
>> + { .format = V4L2_PIX_FMT_P012M, .pixel_enc =
>V4L2_PIXEL_ENC_YUV, .mem_planes = 2, .comp_planes = 2, .bpp = { 2, 4, 0,
>0 }, .hdiv = 2, .vdiv = 2 },
>>
>> /* Bayer RGB formats */
>> { .format = V4L2_PIX_FMT_SBGGR8, .pixel_enc =
>V4L2_PIXEL_ENC_BAYER, .mem_planes = 1, .comp_planes = 1, .bpp = { 1, 0, 0,
>0 }, .hdiv = 1, .vdiv = 1 },
>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c
>> b/drivers/media/v4l2-core/v4l2-ioctl.c
>> index 8e0a0ff62a70..067dbdd0a9ef 100644
>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>> @@ -1348,6 +1348,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc
>*fmt)
>> case V4L2_PIX_FMT_NV24: descr = "Y/UV 4:4:4"; break;
>> case V4L2_PIX_FMT_NV42: descr = "Y/VU 4:4:4"; break;
>> case V4L2_PIX_FMT_P010: descr = "10-bit Y/UV 4:2:0"; break;
>> + case V4L2_PIX_FMT_P012: descr = "12-bit Y/UV 4:2:0"; break;
>> case V4L2_PIX_FMT_NV12_4L4: descr = "Y/UV 4:2:0 (4x4 Linear)";
>break;
>> case V4L2_PIX_FMT_NV12_16L16: descr = "Y/UV 4:2:0 (16x16 Linear)";
>break;
>> case V4L2_PIX_FMT_NV12_32L32: descr = "Y/UV 4:2:0 (32x32 Linear)";
>break;
>> @@ -1358,6 +1359,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc
>*fmt)
>> case V4L2_PIX_FMT_NV61M: descr = "Y/VU 4:2:2 (N-C)"; break;
>> case V4L2_PIX_FMT_NV12MT: descr = "Y/UV 4:2:0 (64x32 MB, N-C)";
>break;
>> case V4L2_PIX_FMT_NV12MT_16X16: descr = "Y/UV 4:2:0 (16x16 MB,
>> N-C)"; break;
>> + case V4L2_PIX_FMT_P012M: descr = "12-bit Y/UV 4:2:0 (N-C)"; break;
>> case V4L2_PIX_FMT_YUV420M: descr = "Planar YUV 4:2:0 (N-C)";
>break;
>> case V4L2_PIX_FMT_YVU420M: descr = "Planar YVU 4:2:0 (N-C)";
>break;
>> case V4L2_PIX_FMT_YUV422M: descr = "Planar YUV 4:2:2 (N-C)";
>break;
>> diff --git a/include/uapi/linux/videodev2.h
>> b/include/uapi/linux/videodev2.h index 1befd181a4cc..5448aa3b7858
>> 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -626,12 +626,14 @@ struct v4l2_pix_format {
>> #define V4L2_PIX_FMT_NV24 v4l2_fourcc('N', 'V', '2', '4') /* 24 Y/CbCr
>4:4:4 */
>> #define V4L2_PIX_FMT_NV42 v4l2_fourcc('N', 'V', '4', '2') /* 24 Y/CrCb
>4:4:4 */
>> #define V4L2_PIX_FMT_P010 v4l2_fourcc('P', '0', '1', '0') /* 24 Y/CbCr
>4:2:0 10-bit per component */
>> +#define V4L2_PIX_FMT_P012 v4l2_fourcc('P', '0', '1', '2') /* 24 Y/CbCr
>4:2:0 12-bit per component */
>>
>> /* two non contiguous planes - one Y, one Cr + Cb interleaved */
>> #define V4L2_PIX_FMT_NV12M v4l2_fourcc('N', 'M', '1', '2') /* 12 Y/CbCr
>4:2:0 */
>> #define V4L2_PIX_FMT_NV21M v4l2_fourcc('N', 'M', '2', '1') /* 21 Y/CrCb
>4:2:0 */
>> #define V4L2_PIX_FMT_NV16M v4l2_fourcc('N', 'M', '1', '6') /* 16 Y/CbCr
>4:2:2 */
>> #define V4L2_PIX_FMT_NV61M v4l2_fourcc('N', 'M', '6', '1') /* 16 Y/CrCb
>4:2:2 */
>> +#define V4L2_PIX_FMT_P012M v4l2_fourcc('P', 'M', '1', '2') /* 24 Y/CbCr
>4:2:0 12-bit per component */
>
>The name of the V4L2_PIX_FMT_ defines in this series are hard to decode.
>
>In this case is it derived from V4L2_PIX_FMT_P010, which really should have
>been named differently, but it's too late now :-(
>
>So I guess we'll stick with this naming, but it's not obvious what 'P012' means
>without referring to documentation.
>
>Oh well.
>
>Regards,
>
> Hans

Hi Hans,
I'll update the format name, as you know, the P012 is following the P010, as they are almost the same, and the Y212 comes from gstreamer (GST_VIDEO_FORMAT_Y212_LE), then I did some naming like that.
I'll correct them in v2 patch.

Ming

>
>>
>> /* three planes - Y Cb, Cr */
>> #define V4L2_PIX_FMT_YUV410 v4l2_fourcc('Y', 'U', 'V', '9') /* 9 YUV 4:1:0
>*/