pixfmt-m420.rst

 1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
 2.. c:namespace:: V4L
 3
 4.. _V4L2-PIX-FMT-M420:
 5
 6**************************
 7V4L2_PIX_FMT_M420 ('M420')
 8**************************
 9
10Format with ½ horizontal and vertical chroma resolution, also known as
11YUV 4:2:0. Hybrid plane line-interleaved layout.
12
13
14Description
15===========
16
17M420 is a YUV format with ½ horizontal and vertical chroma subsampling
18(YUV 4:2:0). Pixels are organized as interleaved luma and chroma planes.
19Two lines of luma data are followed by one line of chroma data.
20
21The luma plane has one byte per pixel. The chroma plane contains
22interleaved CbCr pixels subsampled by ½ in the horizontal and vertical
23directions. Each CbCr pair belongs to four pixels. For example,
24Cb\ :sub:`0`/Cr\ :sub:`0` belongs to Y'\ :sub:`00`, Y'\ :sub:`01`,
25Y'\ :sub:`10`, Y'\ :sub:`11`.
26
27All line lengths are identical: if the Y lines include pad bytes so do
28the CbCr lines.
29
30**Byte Order.**
31Each cell is one byte.
32
33
34.. flat-table::
35    :header-rows:  0
36    :stub-columns: 0
37
38    * - start + 0:
39      - Y'\ :sub:`00`
40      - Y'\ :sub:`01`
41      - Y'\ :sub:`02`
42      - Y'\ :sub:`03`
43    * - start + 4:
44      - Y'\ :sub:`10`
45      - Y'\ :sub:`11`
46      - Y'\ :sub:`12`
47      - Y'\ :sub:`13`
48    * - start + 8:
49      - Cb\ :sub:`00`
50      - Cr\ :sub:`00`
51      - Cb\ :sub:`01`
52      - Cr\ :sub:`01`
53    * - start + 16:
54      - Y'\ :sub:`20`
55      - Y'\ :sub:`21`
56      - Y'\ :sub:`22`
57      - Y'\ :sub:`23`
58    * - start + 20:
59      - Y'\ :sub:`30`
60      - Y'\ :sub:`31`
61      - Y'\ :sub:`32`
62      - Y'\ :sub:`33`
63    * - start + 24:
64      - Cb\ :sub:`10`
65      - Cr\ :sub:`10`
66      - Cb\ :sub:`11`
67      - Cr\ :sub:`11`
68
69
70**Color Sample Location:**
71Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>`
72horizontally and vertically.