diff options
Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-cropcap.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/vidioc-cropcap.xml | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-cropcap.xml b/Documentation/DocBook/media/v4l/vidioc-cropcap.xml deleted file mode 100644 index 50cb940cbe5c..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-cropcap.xml +++ /dev/null @@ -1,166 +0,0 @@ -<refentry id="vidioc-cropcap"> - <refmeta> - <refentrytitle>ioctl VIDIOC_CROPCAP</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_CROPCAP</refname> - <refpurpose>Information about the video cropping and scaling abilities</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>struct v4l2_cropcap -*<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Arguments</title> - - <variablelist> - <varlistentry> - <term><parameter>fd</parameter></term> - <listitem> - <para>&fd;</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>request</parameter></term> - <listitem> - <para>VIDIOC_CROPCAP</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>Applications use this function to query the cropping -limits, the pixel aspect of images and to calculate scale factors. -They set the <structfield>type</structfield> field of a v4l2_cropcap -structure to the respective buffer (stream) type and call the -<constant>VIDIOC_CROPCAP</constant> ioctl with a pointer to this -structure. Drivers fill the rest of the structure. The results are -constant except when switching the video standard. Remember this -switch can occur implicit when switching the video input or -output.</para> - -<para>Do not use the multiplanar buffer types. Use <constant>V4L2_BUF_TYPE_VIDEO_CAPTURE</constant> -instead of <constant>V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE</constant> -and use <constant>V4L2_BUF_TYPE_VIDEO_OUTPUT</constant> instead of -<constant>V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE</constant>.</para> - - <para>This ioctl must be implemented for video capture or output devices that -support cropping and/or scaling and/or have non-square pixels, and for overlay devices.</para> - - <table pgwide="1" frame="none" id="v4l2-cropcap"> - <title>struct <structname>v4l2_cropcap</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>type</structfield></entry> - <entry>Type of the data stream, set by the application. -Only these types are valid here: -<constant>V4L2_BUF_TYPE_VIDEO_CAPTURE</constant>, -<constant>V4L2_BUF_TYPE_VIDEO_OUTPUT</constant> and -<constant>V4L2_BUF_TYPE_VIDEO_OVERLAY</constant>. See <xref linkend="v4l2-buf-type" />.</entry> - </row> - <row> - <entry>struct <link linkend="v4l2-rect-crop">v4l2_rect</link></entry> - <entry><structfield>bounds</structfield></entry> - <entry>Defines the window within capturing or output is -possible, this may exclude for example the horizontal and vertical -blanking areas. The cropping rectangle cannot exceed these limits. -Width and height are defined in pixels, the driver writer is free to -choose origin and units of the coordinate system in the analog -domain.</entry> - </row> - <row> - <entry>struct <link linkend="v4l2-rect-crop">v4l2_rect</link></entry> - <entry><structfield>defrect</structfield></entry> - <entry>Default cropping rectangle, it shall cover the -"whole picture". Assuming pixel aspect 1/1 this could be for example a -640 × 480 rectangle for NTSC, a -768 × 576 rectangle for PAL and SECAM centered over -the active picture area. The same co-ordinate system as for - <structfield>bounds</structfield> is used.</entry> - </row> - <row> - <entry>&v4l2-fract;</entry> - <entry><structfield>pixelaspect</structfield></entry> - <entry><para>This is the pixel aspect (y / x) when no -scaling is applied, the ratio of the actual sampling -frequency and the frequency required to get square -pixels.</para><para>When cropping coordinates refer to square pixels, -the driver sets <structfield>pixelaspect</structfield> to 1/1. Other -common values are 54/59 for PAL and SECAM, 11/10 for NTSC sampled -according to [<xref linkend="itu601" />].</para></entry> - </row> - </tbody> - </tgroup> - </table> - - <!-- NB this table is duplicated in the overlay chapter. --> - - <table pgwide="1" frame="none" id="v4l2-rect-crop"> - <title>struct <structname>v4l2_rect</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__s32</entry> - <entry><structfield>left</structfield></entry> - <entry>Horizontal offset of the top, left corner of the -rectangle, in pixels.</entry> - </row> - <row> - <entry>__s32</entry> - <entry><structfield>top</structfield></entry> - <entry>Vertical offset of the top, left corner of the -rectangle, in pixels.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>width</structfield></entry> - <entry>Width of the rectangle, in pixels.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>height</structfield></entry> - <entry>Height of the rectangle, in pixels.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The &v4l2-cropcap; <structfield>type</structfield> is -invalid.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |