diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/DocBook/media-entities.tmpl | 1 | ||||
-rw-r--r-- | Documentation/DocBook/v4l/nv12mt.gif | bin | 0 -> 2108 bytes | |||
-rw-r--r-- | Documentation/DocBook/v4l/nv12mt_example.gif | bin | 0 -> 6858 bytes | |||
-rw-r--r-- | Documentation/DocBook/v4l/pixfmt-nv12mt.xml | 74 | ||||
-rw-r--r-- | Documentation/DocBook/v4l/pixfmt.xml | 1 |
5 files changed, 76 insertions, 0 deletions
diff --git a/Documentation/DocBook/media-entities.tmpl b/Documentation/DocBook/media-entities.tmpl index 40158ee..5d259c6 100644 --- a/Documentation/DocBook/media-entities.tmpl +++ b/Documentation/DocBook/media-entities.tmpl @@ -272,6 +272,7 @@ <!ENTITY sub-grey SYSTEM "v4l/pixfmt-grey.xml"> <!ENTITY sub-nv12 SYSTEM "v4l/pixfmt-nv12.xml"> <!ENTITY sub-nv12m SYSTEM "v4l/pixfmt-nv12m.xml"> +<!ENTITY sub-nv12mt SYSTEM "v4l/pixfmt-nv12mt.xml"> <!ENTITY sub-nv16 SYSTEM "v4l/pixfmt-nv16.xml"> <!ENTITY sub-packed-rgb SYSTEM "v4l/pixfmt-packed-rgb.xml"> <!ENTITY sub-packed-yuv SYSTEM "v4l/pixfmt-packed-yuv.xml"> diff --git a/Documentation/DocBook/v4l/nv12mt.gif b/Documentation/DocBook/v4l/nv12mt.gif Binary files differnew file mode 100644 index 0000000..ef2d4cf --- /dev/null +++ b/Documentation/DocBook/v4l/nv12mt.gif diff --git a/Documentation/DocBook/v4l/nv12mt_example.gif b/Documentation/DocBook/v4l/nv12mt_example.gif Binary files differnew file mode 100644 index 0000000..df81d68 --- /dev/null +++ b/Documentation/DocBook/v4l/nv12mt_example.gif diff --git a/Documentation/DocBook/v4l/pixfmt-nv12mt.xml b/Documentation/DocBook/v4l/pixfmt-nv12mt.xml new file mode 100644 index 0000000..5cb5bec --- /dev/null +++ b/Documentation/DocBook/v4l/pixfmt-nv12mt.xml @@ -0,0 +1,74 @@ + <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 adjactent 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"> + <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> + + <!-- +Local Variables: +mode: sgml +sgml-parent-document: "pixfmt.sgml" +indent-tabs-mode: nil +End: + --> diff --git a/Documentation/DocBook/v4l/pixfmt.xml b/Documentation/DocBook/v4l/pixfmt.xml index f8436dc..c6fdcbb 100644 --- a/Documentation/DocBook/v4l/pixfmt.xml +++ b/Documentation/DocBook/v4l/pixfmt.xml @@ -709,6 +709,7 @@ information.</para> &sub-yuv411p; &sub-nv12; &sub-nv12m; + &sub-nv12mt; &sub-nv16; </section> |