Mauro Carvalho Chehab 54f38fcae5 media: docs: move uAPI book to userspace-api/media
Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").

As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.

Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-14 10:31:49 +02:00

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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/userspace-api/media/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
.. _V4L2-PIX-FMT-NV16:
.. _V4L2-PIX-FMT-NV61:
******************************************************
V4L2_PIX_FMT_NV16 ('NV16'), V4L2_PIX_FMT_NV61 ('NV61')
******************************************************
V4L2_PIX_FMT_NV61
Formats with ½ horizontal chroma resolution, also known as YUV 4:2:2.
One luminance and one chrominance plane with alternating chroma samples
as opposed to ``V4L2_PIX_FMT_YVU420``
Description
===========
These are two-plane versions of the YUV 4:2:2 format. The three
components are separated into two sub-images or planes. The Y plane is
first. The Y plane has one byte per pixel. For ``V4L2_PIX_FMT_NV16``, a
combined CbCr plane immediately follows the Y plane in memory. The CbCr
plane is the same width and height, in bytes, as the Y plane (and of the
image). Each CbCr pair belongs to two pixels. For example,
Cb\ :sub:`0`/Cr\ :sub:`0` belongs to Y'\ :sub:`00`, Y'\ :sub:`01`.
``V4L2_PIX_FMT_NV61`` is the same except the Cb and Cr bytes are
swapped, the CrCb plane starts with a Cr byte.
If the Y plane has pad bytes after each row, then the CbCr plane has as
many pad bytes after its rows.
**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`
- Cr\ :sub:`00`
- Cb\ :sub:`01`
- Cr\ :sub:`01`
* - start + 20:
- Cb\ :sub:`10`
- Cr\ :sub:`10`
- Cb\ :sub:`11`
- Cr\ :sub:`11`
* - start + 24:
- Cb\ :sub:`20`
- Cr\ :sub:`20`
- Cb\ :sub:`21`
- Cr\ :sub:`21`
* - start + 28:
- Cb\ :sub:`30`
- Cr\ :sub:`30`
- Cb\ :sub:`31`
- Cr\ :sub:`31`
**Color Sample Location:**
.. flat-table::
:header-rows: 0
:stub-columns: 0
* -
- 0
-
- 1
- 2
-
- 3
* - 0
- Y
-
- Y
- Y
-
- Y
* -
-
- C
-
-
- C
-
* - 1
- Y
-
- Y
- Y
-
- Y
* -
-
- C
-
-
- C
-
* -
* - 2
- Y
-
- Y
- Y
-
- Y
* -
-
- C
-
-
- C
-
* - 3
- Y
-
- Y
- Y
-
- Y
* -
-
- C
-
-
- C
-