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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml')
-rw-r--r-- | kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml b/kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml new file mode 100644 index 000000000..8a70a1707 --- /dev/null +++ b/kernel/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml @@ -0,0 +1,66 @@ + <refentry> + <refmeta> + <refentrytitle>V4L2_PIX_FMT_NV12MT ('TM12')</refentrytitle> + &manvol; + </refmeta> + <refnamediv> + <refname id="V4L2-PIX-FMT-NV12MT"><constant>V4L2_PIX_FMT_NV12MT +</constant></refname> + <refpurpose>Formats with ½ horizontal and vertical +chroma resolution. This format has two planes - one for luminance and one for +chrominance. Chroma samples are interleaved. The difference to +<constant>V4L2_PIX_FMT_NV12</constant> is the memory layout. Pixels are +grouped in macroblocks of 64x32 size. The order of macroblocks in memory is +also not standard. + </refpurpose> + </refnamediv> + <refsect1> + <title>Description</title> + + <para>This is the two-plane versions of the YUV 4:2:0 format where data +is grouped into 64x32 macroblocks. The three components are separated into two +sub-images or planes. The Y plane has one byte per pixel and pixels are grouped +into 64x32 macroblocks. The CbCr plane has the same width, in bytes, as the Y +plane (and the image), but is half as tall in pixels. The chroma plane is also +grouped into 64x32 macroblocks.</para> + <para>Width of the buffer has to be aligned to the multiple of 128, and +height alignment is 32. Every four adjacent buffers - two horizontally and two +vertically are grouped together and are located in memory in Z or flipped Z +order. </para> + <para>Layout of macroblocks in memory is presented in the following +figure.</para> + <para><figure id="nv12mt"> + <title><constant>V4L2_PIX_FMT_NV12MT</constant> macroblock Z shape +memory layout</title> + <mediaobject> + <imageobject> + <imagedata fileref="nv12mt.gif" format="GIF" /> + </imageobject> + </mediaobject> + </figure> + The requirement that width is multiple of 128 is implemented because, +the Z shape cannot be cut in half horizontally. In case the vertical resolution +of macroblocks is odd then the last row of macroblocks is arranged in a linear +order. </para> + <para>In case of chroma the layout is identical. Cb and Cr samples are +interleaved. Height of the buffer is aligned to 32. + </para> + <example> + <title>Memory layout of macroblocks in <constant>V4L2_PIX_FMT_NV12 +</constant> format pixel image - extreme case</title> + <para> + <figure id="nv12mt_ex"> + <title>Example <constant>V4L2_PIX_FMT_NV12MT</constant> memory +layout of macroblocks</title> + <mediaobject> + <imageobject> + <imagedata fileref="nv12mt_example.gif" format="GIF" /> + </imageobject> + </mediaobject> + </figure> + Memory layout of macroblocks of <constant>V4L2_PIX_FMT_NV12MT +</constant> format in most extreme case. + </para> + </example> + </refsect1> + </refentry> |