OpenCloudOS-Kernel/Documentation/media/uapi/v4l/pixfmt-yuv411p.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
.. _V4L2-PIX-FMT-YUV411P:
*****************************
V4L2_PIX_FMT_YUV411P ('411P')
*****************************
Format with ¼ horizontal chroma resolution, also known as YUV 4:1:1.
Planar layout as opposed to ``V4L2_PIX_FMT_Y41P``
Description
===========
This format is not commonly used. This is a planar format similar to the
4:2:2 planar format except with half as many chroma. The three
components are separated into three sub-images or planes. The Y plane is
first. The Y plane has one byte per pixel. The Cb plane immediately
follows the Y plane in memory. The Cb plane is ¼ the width of the Y
plane (and of the image). Each Cb belongs to 4 pixels all on the same
row. For example, Cb\ :sub:`0` belongs to Y'\ :sub:`00`, Y'\ :sub:`01`,
Y'\ :sub:`02` and Y'\ :sub:`03`. Following the Cb plane is the Cr plane,
just like the Cb plane.
If the Y plane has pad bytes after each row, then the Cr and Cb planes
have ¼ as many pad bytes after their rows. In other words, four C x rows
(including padding) is exactly as long as one Y row (including padding).
**Byte Order.**
Each cell is one byte.
.. flat-table::
:header-rows: 0
:stub-columns: 0
* - start + 0:
- Y'\ :sub:`00`
- Y'\ :sub:`01`
- Y'\ :sub:`02`
- Y'\ :sub:`03`
* - start + 4:
- Y'\ :sub:`10`
- Y'\ :sub:`11`
- Y'\ :sub:`12`
- Y'\ :sub:`13`
* - start + 8:
- Y'\ :sub:`20`
- Y'\ :sub:`21`
- Y'\ :sub:`22`
- Y'\ :sub:`23`
* - start + 12:
- Y'\ :sub:`30`
- Y'\ :sub:`31`
- Y'\ :sub:`32`
- Y'\ :sub:`33`
* - start + 16:
- Cb\ :sub:`00`
* - start + 17:
- Cb\ :sub:`10`
* - start + 18:
- Cb\ :sub:`20`
* - start + 19:
- Cb\ :sub:`30`
* - start + 20:
- Cr\ :sub:`00`
* - start + 21:
- Cr\ :sub:`10`
* - start + 22:
- Cr\ :sub:`20`
* - start + 23:
- Cr\ :sub:`30`
**Color Sample Location:**
.. flat-table::
:header-rows: 0
:stub-columns: 0
* -
- 0
- 1
-
- 2
- 3
* - 0
- Y
- Y
- C
- Y
- Y
* - 1
- Y
- Y
- C
- Y
- Y
* - 2
- Y
- Y
- C
- Y
- Y
* - 3
- Y
- Y
- C
- Y
- Y