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| author | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2020-03-04 10:21:39 +0100 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2020-04-14 10:31:49 +0200 |
| commit | 54f38fcae536ea202ce7d6a359521492fba30c1f (patch) | |
| tree | dd1a2b36d8de0b13702f2716526ad3b91650e090 /Documentation/userspace-api/media/v4l/pixfmt-m420.rst | |
| parent | 5dfb8db56b273740a76e8687ee7efb4b2c0ec83b (diff) | |
media: docs: move uAPI book to userspace-api/media
Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").
As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.
Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Diffstat (limited to 'Documentation/userspace-api/media/v4l/pixfmt-m420.rst')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/pixfmt-m420.rst | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-m420.rst b/Documentation/userspace-api/media/v4l/pixfmt-m420.rst new file mode 100644 index 000000000000..5180bbe16c6e --- /dev/null +++ b/Documentation/userspace-api/media/v4l/pixfmt-m420.rst @@ -0,0 +1,133 @@ +.. Permission is granted to copy, distribute and/or modify this +.. document under the terms of the GNU Free Documentation License, +.. Version 1.1 or any later version published by the Free Software +.. Foundation, with no Invariant Sections, no Front-Cover Texts +.. and no Back-Cover Texts. A copy of the license is included at +.. Documentation/userspace-api/media/fdl-appendix.rst. +.. +.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections + +.. _V4L2-PIX-FMT-M420: + +************************** +V4L2_PIX_FMT_M420 ('M420') +************************** + +Format with ½ horizontal and vertical chroma resolution, also known as +YUV 4:2:0. Hybrid plane line-interleaved layout. + + +Description +=========== + +M420 is a YUV format with ½ horizontal and vertical chroma subsampling +(YUV 4:2:0). Pixels are organized as interleaved luma and chroma planes. +Two lines of luma data are followed by one line of chroma data. + +The luma plane has one byte per pixel. The chroma plane contains +interleaved CbCr pixels subsampled by ½ in the horizontal and vertical +directions. 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`. + +All line lengths are identical: if the Y lines include pad bytes so do +the CbCr lines. + +**Byte Order.** +Each cell is one byte. + + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + * - start + 0: + - Y'\ :sub:`00` + - Y'\ :sub:`01` + - Y'\ :sub:`02` + - Y'\ :sub:`03` + * - start + 4: + - Y'\ :sub:`10` + - Y'\ :sub:`11` + - Y'\ :sub:`12` + - Y'\ :sub:`13` + * - start + 8: + - Cb\ :sub:`00` + - Cr\ :sub:`00` + - Cb\ :sub:`01` + - Cr\ :sub:`01` + * - start + 16: + - Y'\ :sub:`20` + - Y'\ :sub:`21` + - Y'\ :sub:`22` + - Y'\ :sub:`23` + * - start + 20: + - Y'\ :sub:`30` + - Y'\ :sub:`31` + - Y'\ :sub:`32` + - Y'\ :sub:`33` + * - start + 24: + - Cb\ :sub:`10` + - Cr\ :sub:`10` + - Cb\ :sub:`11` + - 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 |