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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+
+.. _V4L2-PIX-FMT-YUV420M:
+.. _v4l2-pix-fmt-yvu420m:
+
+************************************************************
+V4L2_PIX_FMT_YUV420M ('YM12'), V4L2_PIX_FMT_YVU420M ('YM21')
+************************************************************
+
+
+V4L2_PIX_FMT_YVU420M
+Variation of ``V4L2_PIX_FMT_YUV420`` and ``V4L2_PIX_FMT_YVU420`` with
+planes non contiguous in memory.
+
+
+Description
+===========
+
+This is a multi-planar format, as opposed to a packed format. The three
+components are separated into three sub-images or planes.
+
+The Y plane is first. The Y plane has one byte per pixel. For
+``V4L2_PIX_FMT_YUV420M`` the Cb data constitutes the second plane which
+is half the width and half the height of the Y plane (and of the image).
+Each Cb belongs to four pixels, a two-by-two square of the image. For
+example, Cb\ :sub:`0` belongs to Y'\ :sub:`00`, Y'\ :sub:`01`,
+Y'\ :sub:`10`, and Y'\ :sub:`11`. The Cr data, just like the Cb plane,
+is in the third plane.
+
+``V4L2_PIX_FMT_YVU420M`` is the same except the Cr data is stored in the
+second plane and the Cb data in the third plane.
+
+If the Y plane has pad bytes after each row, then the Cb and Cr planes
+have half as many pad bytes after their rows. In other words, two Cx
+rows (including padding) is exactly as long as one Y row (including
+padding).
+
+``V4L2_PIX_FMT_YUV420M`` and ``V4L2_PIX_FMT_YVU420M`` are intended to be
+used only in drivers and applications that support the multi-planar API,
+described in :ref:`planar-apis`.
+
+**Byte Order.**
+Each cell is one byte.
+
+
+
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+
+ * - start0 + 0:
+ - Y'\ :sub:`00`
+ - Y'\ :sub:`01`
+ - Y'\ :sub:`02`
+ - Y'\ :sub:`03`
+ * - start0 + 4:
+ - Y'\ :sub:`10`
+ - Y'\ :sub:`11`
+ - Y'\ :sub:`12`
+ - Y'\ :sub:`13`
+ * - start0 + 8:
+ - Y'\ :sub:`20`
+ - Y'\ :sub:`21`
+ - Y'\ :sub:`22`
+ - Y'\ :sub:`23`
+ * - start0 + 12:
+ - Y'\ :sub:`30`
+ - Y'\ :sub:`31`
+ - Y'\ :sub:`32`
+ - Y'\ :sub:`33`
+ * -
+ * - start1 + 0:
+ - Cb\ :sub:`00`
+ - Cb\ :sub:`01`
+ * - start1 + 2:
+ - Cb\ :sub:`10`
+ - Cb\ :sub:`11`
+ * -
+ * - start2 + 0:
+ - Cr\ :sub:`00`
+ - Cr\ :sub:`01`
+ * - start2 + 2:
+ - Cr\ :sub:`10`
+ - Cr\ :sub:`11`
+
+
+**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
+ * -
+ * - 2
+ - Y
+ -
+ - Y
+ -
+ - Y
+ -
+ - Y
+ * -
+ -
+ - C
+ -
+ -
+ -
+ - C
+ -
+ * - 3
+ - Y
+ -
+ - Y
+ -
+ - Y
+ -
+ - Y