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Diffstat (limited to 'Documentation/DocBook/v4l/planar-apis.xml')
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diff --git a/Documentation/DocBook/v4l/planar-apis.xml b/Documentation/DocBook/v4l/planar-apis.xml deleted file mode 100644 index 878ce2040488..000000000000 --- a/Documentation/DocBook/v4l/planar-apis.xml +++ /dev/null @@ -1,62 +0,0 @@ -<section id="planar-apis"> - <title>Single- and multi-planar APIs</title> - - <para>Some devices require data for each input or output video frame - to be placed in discontiguous memory buffers. In such cases, one - video frame has to be addressed using more than one memory address, i.e. one - pointer per "plane". A plane is a sub-buffer of the current frame. For - examples of such formats see <xref linkend="pixfmt" />.</para> - - <para>Initially, V4L2 API did not support multi-planar buffers and a set of - extensions has been introduced to handle them. Those extensions constitute - what is being referred to as the "multi-planar API".</para> - - <para>Some of the V4L2 API calls and structures are interpreted differently, - depending on whether single- or multi-planar API is being used. An application - can choose whether to use one or the other by passing a corresponding buffer - type to its ioctl calls. Multi-planar versions of buffer types are suffixed - with an `_MPLANE' string. For a list of available multi-planar buffer types - see &v4l2-buf-type;. - </para> - - <section> - <title>Multi-planar formats</title> - <para>Multi-planar API introduces new multi-planar formats. Those formats - use a separate set of FourCC codes. It is important to distinguish between - the multi-planar API and a multi-planar format. Multi-planar API calls can - handle all single-planar formats as well (as long as they are passed in - multi-planar API structures), while the single-planar API cannot - handle multi-planar formats.</para> - </section> - - <section> - <title>Calls that distinguish between single and multi-planar APIs</title> - <variablelist> - <varlistentry> - <term>&VIDIOC-QUERYCAP;</term> - <listitem><para>Two additional multi-planar capabilities are added. They can - be set together with non-multi-planar ones for devices that handle - both single- and multi-planar formats.</para></listitem> - </varlistentry> - <varlistentry> - <term>&VIDIOC-G-FMT;, &VIDIOC-S-FMT;, &VIDIOC-TRY-FMT;</term> - <listitem><para>New structures for describing multi-planar formats are added: - &v4l2-pix-format-mplane; and &v4l2-plane-pix-format;. Drivers may - define new multi-planar formats, which have distinct FourCC codes from - the existing single-planar ones.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>&VIDIOC-QBUF;, &VIDIOC-DQBUF;, &VIDIOC-QUERYBUF;</term> - <listitem><para>A new &v4l2-plane; structure for describing planes is added. - Arrays of this structure are passed in the new - <structfield>m.planes</structfield> field of &v4l2-buffer;.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>&VIDIOC-REQBUFS;</term> - <listitem><para>Will allocate multi-planar buffers as requested.</para></listitem> - </varlistentry> - </variablelist> - </section> -</section> |