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diff --git a/Documentation/media/uapi/v4l/pixfmt-nv12m.rst b/Documentation/media/uapi/v4l/pixfmt-nv12m.rst new file mode 100644 index 000000000000..a4e7eaeccea8 --- /dev/null +++ b/Documentation/media/uapi/v4l/pixfmt-nv12m.rst @@ -0,0 +1,238 @@ +.. -*- 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 |