1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3.. _V4L2-PIX-FMT-YUV420M: 4.. _v4l2-pix-fmt-yvu420m: 5 6************************************************************ 7V4L2_PIX_FMT_YUV420M ('YM12'), V4L2_PIX_FMT_YVU420M ('YM21') 8************************************************************ 9 10 11V4L2_PIX_FMT_YVU420M 12Variation of ``V4L2_PIX_FMT_YUV420`` and ``V4L2_PIX_FMT_YVU420`` with 13planes non contiguous in memory. 14 15 16Description 17=========== 18 19This is a multi-planar format, as opposed to a packed format. The three 20components are separated into three sub-images or planes. 21 22The Y plane is first. The Y plane has one byte per pixel. For 23``V4L2_PIX_FMT_YUV420M`` the Cb data constitutes the second plane which 24is half the width and half the height of the Y plane (and of the image). 25Each Cb belongs to four pixels, a two-by-two square of the image. For 26example, Cb\ :sub:`0` belongs to Y'\ :sub:`00`, Y'\ :sub:`01`, 27Y'\ :sub:`10`, and Y'\ :sub:`11`. The Cr data, just like the Cb plane, 28is in the third plane. 29 30``V4L2_PIX_FMT_YVU420M`` is the same except the Cr data is stored in the 31second plane and the Cb data in the third plane. 32 33If the Y plane has pad bytes after each row, then the Cb and Cr planes 34have half as many pad bytes after their rows. In other words, two Cx 35rows (including padding) is exactly as long as one Y row (including 36padding). 37 38``V4L2_PIX_FMT_YUV420M`` and ``V4L2_PIX_FMT_YVU420M`` are intended to be 39used only in drivers and applications that support the multi-planar API, 40described in :ref:`planar-apis`. 41 42**Byte Order.** 43Each cell is one byte. 44 45 46 47 48.. flat-table:: 49 :header-rows: 0 50 :stub-columns: 0 51 52 * - start0 + 0: 53 - Y'\ :sub:`00` 54 - Y'\ :sub:`01` 55 - Y'\ :sub:`02` 56 - Y'\ :sub:`03` 57 * - start0 + 4: 58 - Y'\ :sub:`10` 59 - Y'\ :sub:`11` 60 - Y'\ :sub:`12` 61 - Y'\ :sub:`13` 62 * - start0 + 8: 63 - Y'\ :sub:`20` 64 - Y'\ :sub:`21` 65 - Y'\ :sub:`22` 66 - Y'\ :sub:`23` 67 * - start0 + 12: 68 - Y'\ :sub:`30` 69 - Y'\ :sub:`31` 70 - Y'\ :sub:`32` 71 - Y'\ :sub:`33` 72 * - 73 * - start1 + 0: 74 - Cb\ :sub:`00` 75 - Cb\ :sub:`01` 76 * - start1 + 2: 77 - Cb\ :sub:`10` 78 - Cb\ :sub:`11` 79 * - 80 * - start2 + 0: 81 - Cr\ :sub:`00` 82 - Cr\ :sub:`01` 83 * - start2 + 2: 84 - Cr\ :sub:`10` 85 - Cr\ :sub:`11` 86 87 88**Color Sample Location:** 89 90 91 92.. flat-table:: 93 :header-rows: 0 94 :stub-columns: 0 95 96 * - 97 - 0 98 - 99 - 1 100 - 101 - 2 102 - 103 - 3 104 * - 0 105 - Y 106 - 107 - Y 108 - 109 - Y 110 - 111 - Y 112 * - 113 - 114 - C 115 - 116 - 117 - 118 - C 119 - 120 * - 1 121 - Y 122 - 123 - Y 124 - 125 - Y 126 - 127 - Y 128 * - 129 * - 2 130 - Y 131 - 132 - Y 133 - 134 - Y 135 - 136 - Y 137 * - 138 - 139 - C 140 - 141 - 142 - 143 - C 144 - 145 * - 3 146 - Y 147 - 148 - Y 149 - 150 - Y 151 - 152 - Y 153