diff options
Diffstat (limited to 'Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml | 66 |
1 files changed, 0 insertions, 66 deletions
diff --git a/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml b/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml deleted file mode 100644 index 8a70a1707b7a..000000000000 --- a/Documentation/DocBook/media/v4l/pixfmt-nv12mt.xml +++ /dev/null @@ -1,66 +0,0 @@ - <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> |