| .. -*- coding: utf-8; mode: rst -*- |
| |
| .. _V4L2-PIX-FMT-YVU420: |
| |
| ********************************************************** |
| V4L2_PIX_FMT_YVU420 ('YV12'), V4L2_PIX_FMT_YUV420 ('YU12') |
| ********************************************************** |
| |
| *man V4L2_PIX_FMT_YVU420(2)* |
| |
| V4L2_PIX_FMT_YUV420 |
| Planar formats with ½ horizontal and vertical chroma resolution, also |
| known as YUV 4:2:0 |
| |
| |
| Description |
| =========== |
| |
| These are planar formats, 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_YVU420``, the Cr plane immediately follows the Y plane in |
| memory. The Cr plane is half the width and half the height of the Y |
| plane (and of the image). Each Cr belongs to four pixels, a two-by-two |
| square of the image. For example, Cr\ :sub:`0` belongs to Y'\ :sub:`00`, |
| Y'\ :sub:`01`, Y'\ :sub:`10`, and Y'\ :sub:`11`. Following the Cr plane |
| is the Cb plane, just like the Cr plane. ``V4L2_PIX_FMT_YUV420`` is the |
| same except the Cb plane comes first, then the Cr plane. |
| |
| If the Y plane has pad bytes after each row, then the Cr and Cb 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). |
| |
| **Byte Order..** |
| |
| Each cell is one byte. |
| |
| |
| |
| .. flat-table:: |
| :header-rows: 0 |
| :stub-columns: 0 |
| :widths: 2 1 1 1 1 |
| |
| |
| - .. row 1 |
| |
| - start + 0: |
| |
| - Y'\ :sub:`00` |
| |
| - Y'\ :sub:`01` |
| |
| - Y'\ :sub:`02` |
| |
| - Y'\ :sub:`03` |
| |
| - .. row 2 |
| |
| - start + 4: |
| |
| - Y'\ :sub:`10` |
| |
| - Y'\ :sub:`11` |
| |
| - Y'\ :sub:`12` |
| |
| - Y'\ :sub:`13` |
| |
| - .. row 3 |
| |
| - start + 8: |
| |
| - Y'\ :sub:`20` |
| |
| - Y'\ :sub:`21` |
| |
| - Y'\ :sub:`22` |
| |
| - Y'\ :sub:`23` |
| |
| - .. row 4 |
| |
| - start + 12: |
| |
| - Y'\ :sub:`30` |
| |
| - Y'\ :sub:`31` |
| |
| - Y'\ :sub:`32` |
| |
| - Y'\ :sub:`33` |
| |
| - .. row 5 |
| |
| - start + 16: |
| |
| - Cr\ :sub:`00` |
| |
| - Cr\ :sub:`01` |
| |
| - .. row 6 |
| |
| - start + 18: |
| |
| - Cr\ :sub:`10` |
| |
| - Cr\ :sub:`11` |
| |
| - .. row 7 |
| |
| - start + 20: |
| |
| - Cb\ :sub:`00` |
| |
| - Cb\ :sub:`01` |
| |
| - .. row 8 |
| |
| - start + 22: |
| |
| - Cb\ :sub:`10` |
| |
| - Cb\ :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 |
| |
| |
| |
| |
| .. ------------------------------------------------------------------------------ |
| .. This file was automatically converted from DocBook-XML with the dbxml |
| .. library (https://github.com/return42/sphkerneldoc). The origin XML comes |
| .. from the linux kernel, refer to: |
| .. |
| .. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook |
| .. ------------------------------------------------------------------------------ |