linux/linux-5.4.31/Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst

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.. Permission is granted to copy, distribute and/or modify this
.. document under the terms of the GNU Free Documentation License,
.. Version 1.1 or any later version published by the Free Software
.. Foundation, with no Invariant Sections, no Front-Cover Texts
.. and no Back-Cover Texts. A copy of the license is included at
.. Documentation/media/uapi/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
******************************
Multi-planar format structures
******************************
The struct :c:type:`v4l2_plane_pix_format` structures define size
and layout for each of the planes in a multi-planar format. The
struct :c:type:`v4l2_pix_format_mplane` structure contains
information common to all planes (such as image width and height) and an
array of struct :c:type:`v4l2_plane_pix_format` structures,
describing all planes of that format.
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
.. c:type:: v4l2_plane_pix_format
.. flat-table:: struct v4l2_plane_pix_format
:header-rows: 0
:stub-columns: 0
:widths: 1 1 2
* - __u32
- ``sizeimage``
- Maximum size in bytes required for image data in this plane,
set by the driver. When the image consists of variable length
compressed data this is the number of bytes required by the
codec to support the worst-case compression scenario.
The driver will set the value for uncompressed images.
Clients are allowed to set the sizeimage field for variable length
compressed data flagged with ``V4L2_FMT_FLAG_COMPRESSED`` at
:ref:`VIDIOC_ENUM_FMT`, but the driver may ignore it and set the
value itself, or it may modify the provided value based on
alignment requirements or minimum/maximum size requirements.
If the client wants to leave this to the driver, then it should
set sizeimage to 0.
* - __u32
- ``bytesperline``
- Distance in bytes between the leftmost pixels in two adjacent
lines. See struct :c:type:`v4l2_pix_format`.
* - __u16
- ``reserved[6]``
- Reserved for future extensions. Should be zeroed by drivers and
applications.
.. raw:: latex
\small
.. tabularcolumns:: |p{4.4cm}|p{5.6cm}|p{7.5cm}|
.. c:type:: v4l2_pix_format_mplane
.. flat-table:: struct v4l2_pix_format_mplane
:header-rows: 0
:stub-columns: 0
:widths: 1 1 2
* - __u32
- ``width``
- Image width in pixels. See struct
:c:type:`v4l2_pix_format`.
* - __u32
- ``height``
- Image height in pixels. See struct
:c:type:`v4l2_pix_format`.
* - __u32
- ``pixelformat``
- The pixel format. Both single- and multi-planar four character
codes can be used.
* - __u32
- ``field``
- Field order, from enum :c:type:`v4l2_field`.
See struct :c:type:`v4l2_pix_format`.
* - __u32
- ``colorspace``
- Colorspace encoding, from enum :c:type:`v4l2_colorspace`.
See struct :c:type:`v4l2_pix_format`.
* - struct :c:type:`v4l2_plane_pix_format`
- ``plane_fmt[VIDEO_MAX_PLANES]``
- An array of structures describing format of each plane this pixel
format consists of. The number of valid entries in this array has
to be put in the ``num_planes`` field.
* - __u8
- ``num_planes``
- Number of planes (i.e. separate memory buffers) for this format
and the number of valid entries in the ``plane_fmt`` array.
* - __u8
- ``flags``
- Flags set by the application or driver, see :ref:`format-flags`.
* - :cspan:`2` union { (anonymous)
* - __u8
- ``ycbcr_enc``
- Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
This information supplements the ``colorspace`` and must be set by
the driver for capture streams and by the application for output
streams, see :ref:`colorspaces`.
* - __u8
- ``hsv_enc``
- HSV encoding, from enum :c:type:`v4l2_hsv_encoding`.
This information supplements the ``colorspace`` and must be set by
the driver for capture streams and by the application for output
streams, see :ref:`colorspaces`.
* - :cspan:`2` }
* - __u8
- ``quantization``
- Quantization range, from enum :c:type:`v4l2_quantization`.
This information supplements the ``colorspace`` and must be set by
the driver for capture streams and by the application for output
streams, see :ref:`colorspaces`.
* - __u8
- ``xfer_func``
- Transfer function, from enum :c:type:`v4l2_xfer_func`.
This information supplements the ``colorspace`` and must be set by
the driver for capture streams and by the application for output
streams, see :ref:`colorspaces`.
* - __u8
- ``reserved[7]``
- Reserved for future extensions. Should be zeroed by drivers and
applications.
.. raw:: latex
\normalsize