[v4,4/5] docs: Document CLL and Mastering display colorimetry controls

Document Content Light Level and Mastering Display v4l2 colorimetry
controls.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 .../media/v4l/ext-ctrls-colorimetry.rst       | 71 +++++++++++++++++++
 .../media/videodev2.h.rst.exceptions          |  2 +
 2 files changed, 73 insertions(+)

On 20/01/2021 10:26, Stanimir Varbanov wrote:
> Document Content Light Level and Mastering Display v4l2 colorimetry
> controls.
> 
> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
> ---
>  .../media/v4l/ext-ctrls-colorimetry.rst       | 71 +++++++++++++++++++
>  .../media/videodev2.h.rst.exceptions          |  2 +
>  2 files changed, 73 insertions(+)
> 
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-colorimetry.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-colorimetry.rst
> index 6b0cd2054e84..e7e55323651f 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-colorimetry.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-colorimetry.rst
> @@ -17,3 +17,74 @@ Colorimetry Control IDs
>      The Colorimetry class descriptor. Calling
>      :ref:`VIDIOC_QUERYCTRL` for this control will
>      return a description of this control class.
> +
> +``V4L2_CID_COLORIMETRY_HDR10_CLL_INFO (struct)``
> +    The Content Light Level defines upper bounds for the nominal target
> +    brightness light level of the pictures.
> +
> +.. c:type:: v4l2_ctrl_hdr10_cll_info
> +
> +.. cssclass:: longtable
> +
> +.. flat-table:: struct v4l2_ctrl_hdr10_cll_info
> +    :header-rows:  0
> +    :stub-columns: 0
> +    :widths:       1 1 2
> +
> +    * - __u16
> +      - ``max_content_light_level``
> +      - The upper bound for the maximum light level among all individual
> +        samples for the pictures of a coded video sequence, cd/m2. When

For this document:

cd/m2 -> cd/m\ :sup:`2`

> +        equal to 0 no such upper bound is present.
> +    * - __u16
> +      - ``max_pic_average_light_level``
> +      - The upper bound for the maximum average light level among the
> +        samples for any individual picture of a coded video sequence, cd/m2.
> +        When equal to 0 no such upper bound is present.
> +
> +``V4L2_CID_COLORIMETRY_HDR10_MASTERING_DISPLAY (struct)``
> +    The mastering display defines the colour volume (the colour primaries,

For this document: colour -> color

(The US spelling is used)

> +    white point and luminance range) of a display considered to be the
> +    mastering display for the current video content.
> +
> +.. c:type:: v4l2_ctrl_hdr10_mastering_display
> +
> +.. cssclass:: longtable
> +
> +.. flat-table:: struct v4l2_ctrl_hdr10_mastering_display
> +    :header-rows:  0
> +    :stub-columns: 0
> +    :widths:       1 1 2
> +
> +    * - __u16
> +      - ``display_primaries_x[3]``
> +      - Specifies the normalized x chromaticity coordinate of the colour
> +        primary component c of the mastering display in increments of 0.00002.
> +        For describing the mastering display that uses Red, Green and Blue
> +        colour primaries, index value c equal to 0 corresponds to the Green
> +        primary, c equal to 1 corresponds to Blue primary and c equal to 2
> +        corresponds to the Red colour primary.
> +    * - __u16
> +      - ``display_primaries_y[3]``
> +      - Specifies the normalized y chromaticity coordinate of the colour
> +        primary component c of the mastering display in increments of 0.00002.
> +        For describing the mastering display that uses Red, Green and Blue
> +        colour primaries, index value c equal to 0 corresponds to the Green
> +        primary, c equal to 1 corresponds to Blue primary and c equal to 2
> +        corresponds to Red colour primary.
> +    * - __u16
> +      - ``white_point_x``
> +      - Specifies the normalized x chromaticity coordinate of the white
> +        point of the mastering display in increments of 0.00002.
> +    * - __u16
> +      - ``white_point_y``
> +      - Specifies the normalized y chromaticity coordinate of the white
> +        point of the mastering display in increments of 0.00002.
> +    * - __u32
> +      - ``max_luminance``
> +      - Specifies the nominal maximum display luminance of the mastering
> +        display in units of 0.0001 cd/m2.
> +    * - __u32
> +      - ``min_luminance``
> +      - specifies the nominal minimum display luminance of the mastering
> +        display in units of 0.0001 cd/m2.
> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> index 0ed170c6e720..af4b8b87c5d7 100644
> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> @@ -147,6 +147,8 @@ replace symbol V4L2_CTRL_TYPE_HEVC_PPS :c:type:`v4l2_ctrl_type`
>  replace symbol V4L2_CTRL_TYPE_HEVC_SLICE_PARAMS :c:type:`v4l2_ctrl_type`
>  replace symbol V4L2_CTRL_TYPE_AREA :c:type:`v4l2_ctrl_type`
>  replace symbol V4L2_CTRL_TYPE_FWHT_PARAMS :c:type:`v4l2_ctrl_type`
> +replace symbol V4L2_CTRL_TYPE_HDR10_CLL_INFO :c:type:`v4l2_ctrl_hdr10_cll_info`
> +replace symbol V4L2_CTRL_TYPE_HDR10_MASTERING_DISPLAY :c:type:`v4l2_ctrl_hdr10_mastering_display`

No, these two should be :c:type:`v4l2_ctrl_type` like the others.

>  
>  # V4L2 capability defines
>  replace define V4L2_CAP_VIDEO_CAPTURE device-capabilities
> 

You also need to document the new p_hdr10_cll and p_hdr10_mastering
fields in Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst.

Regards,

	Hans