Merge branch 'for-viro' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi...

[deliverable/linux.git] / Documentation / media / uapi / v4l / pixfmt-nv12m.rst

.. -*- coding: utf-8; mode: rst -*-

.. _V4L2-PIX-FMT-NV12M:
.. _v4l2-pix-fmt-nv12mt-16x16:
.. _V4L2-PIX-FMT-NV21M:

***********************************************************************************
V4L2_PIX_FMT_NV12M ('NM12'), V4L2_PIX_FMT_NV21M ('NM21'), V4L2_PIX_FMT_NV12MT_16X16
***********************************************************************************

*man V4L2_PIX_FMT_NV12M(2)*

V4L2_PIX_FMT_NV21M
V4L2_PIX_FMT_NV12MT_16X16
Variation of ``V4L2_PIX_FMT_NV12`` and ``V4L2_PIX_FMT_NV21`` with planes
non contiguous in memory.


Description
===========

This is a multi-planar, two-plane version of the YUV 4:2:0 format. The
three components are separated into two sub-images or planes.
``V4L2_PIX_FMT_NV12M`` differs from ``V4L2_PIX_FMT_NV12`` in that the
two planes are non-contiguous in memory, i.e. the chroma plane do not
necessarily immediately follows the luma plane. The luminance data
occupies the first plane. The Y plane has one byte per pixel. In the
second plane there is a chrominance data with alternating chroma
samples. The CbCr plane is the same width, in bytes, as the Y plane (and
of the image), but is half as tall in pixels. Each CbCr pair belongs to
four pixels. For example, Cb\ :sub:`0`/Cr\ :sub:`0` belongs to
Y'\ :sub:`00`, Y'\ :sub:`01`, Y'\ :sub:`10`, Y'\ :sub:`11`.
``V4L2_PIX_FMT_NV12MT_16X16`` is the tiled version of
``V4L2_PIX_FMT_NV12M`` with 16x16 macroblock tiles. Here pixels are
arranged in 16x16 2D tiles and tiles are arranged in linear order in
memory. ``V4L2_PIX_FMT_NV21M`` is the same as ``V4L2_PIX_FMT_NV12M``
except the Cb and Cr bytes are swapped, the CrCb plane starts with a Cr
byte.

``V4L2_PIX_FMT_NV12M`` is intended to be used only in drivers and
applications that support the multi-planar API, described in
:ref:`planar-apis`.

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
    :widths:       2 1 1 1 1


    -  .. row 1

       -  start0 + 0:

       -  Y'\ :sub:`00`

       -  Y'\ :sub:`01`

       -  Y'\ :sub:`02`

       -  Y'\ :sub:`03`

    -  .. row 2

       -  start0 + 4:

       -  Y'\ :sub:`10`

       -  Y'\ :sub:`11`

       -  Y'\ :sub:`12`

       -  Y'\ :sub:`13`

    -  .. row 3

       -  start0 + 8:

       -  Y'\ :sub:`20`

       -  Y'\ :sub:`21`

       -  Y'\ :sub:`22`

       -  Y'\ :sub:`23`

    -  .. row 4

       -  start0 + 12:

       -  Y'\ :sub:`30`

       -  Y'\ :sub:`31`

       -  Y'\ :sub:`32`

       -  Y'\ :sub:`33`

    -  .. row 5

       -

    -  .. row 6

       -  start1 + 0:

       -  Cb\ :sub:`00`

       -  Cr\ :sub:`00`

       -  Cb\ :sub:`01`

       -  Cr\ :sub:`01`

    -  .. row 7

       -  start1 + 4:

       -  Cb\ :sub:`10`

       -  Cr\ :sub:`10`

       -  Cb\ :sub:`11`

       -  Cr\ :sub:`11`


**Color Sample Location..**



.. flat-table::
    :header-rows:  0
    :stub-columns: 0


    -  .. row 1

       -
       -  0

       -
       -  1

       -  2

       -
       -  3

    -  .. row 2

       -  0

       -  Y

       -
       -  Y

       -  Y

       -
       -  Y

    -  .. row 3

       -
       -
       -  C

       -
       -
       -  C

       -

    -  .. row 4

       -  1

       -  Y

       -
       -  Y

       -  Y

       -
       -  Y

    -  .. row 5

       -

    -  .. row 6

       -  2

       -  Y

       -
       -  Y

       -  Y

       -
       -  Y

    -  .. row 7

       -
       -
       -  C

       -
       -
       -
       -  C

       -

    -  .. row 8

       -  3

       -  Y

       -
       -  Y

       -  Y

       -
       -  Y