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Diffstat (limited to 'v4l2-spec/vidioc-g-crop.sgml')
-rw-r--r-- | v4l2-spec/vidioc-g-crop.sgml | 143 |
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diff --git a/v4l2-spec/vidioc-g-crop.sgml b/v4l2-spec/vidioc-g-crop.sgml deleted file mode 100644 index d235b1ded..000000000 --- a/v4l2-spec/vidioc-g-crop.sgml +++ /dev/null @@ -1,143 +0,0 @@ -<refentry id="vidioc-g-crop"> - <refmeta> - <refentrytitle>ioctl VIDIOC_G_CROP, VIDIOC_S_CROP</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_G_CROP</refname> - <refname>VIDIOC_S_CROP</refname> - <refpurpose>Get or set the current cropping rectangle</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_crop *<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>const struct v4l2_crop *<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_G_CROP, VIDIOC_S_CROP</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>To query the cropping rectangle size and position -applications set the <structfield>type</structfield> field of a -<structname>v4l2_crop</structname> structure to the respective buffer -(stream) type and call the <constant>VIDIOC_G_CROP</constant> ioctl -with a pointer to this structure. The driver fills the rest of the -structure or returns the &EINVAL; if cropping is not supported.</para> - - <para>To change the cropping rectangle applications initialize the -<structfield>type</structfield> and &v4l2-rect; substructure named -<structfield>c</structfield> of a v4l2_crop structure and call the -<constant>VIDIOC_S_CROP</constant> ioctl with a pointer to this -structure.</para> - - <para>The driver first adjusts the requested dimensions against -hardware limits, &ie; the bounds given by the capture/output window, -and it rounds to the closest possible values of horizontal and -vertical offset, width and height. In particular the driver must round -the vertical offset of the cropping rectangle to frame lines modulo -two, such that the field order cannot be confused.</para> - - <para>Second the driver adjusts the image size (the opposite -rectangle of the scaling process, source or target depending on the -data direction) to the closest size possible while maintaining the -current horizontal and vertical scaling factor.</para> - - <para>Finally the driver programs the hardware with the actual -cropping and image parameters. <constant>VIDIOC_S_CROP</constant> is a -write-only ioctl, it does not return the actual parameters. To query -them applications must call <constant>VIDIOC_G_CROP</constant> and -&VIDIOC-G-FMT;. When the parameters are unsuitable the application may -modify the cropping or image parameters and repeat the cycle until -satisfactory parameters have been negotiated.</para> - - <para>When cropping is not supported then no parameters are -changed and <constant>VIDIOC_S_CROP</constant> returns the -&EINVAL;.</para> - - <table pgwide="1" frame="none" id="v4l2-crop"> - <title>struct <structname>v4l2_crop</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>&v4l2-buf-type;</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>, -<constant>V4L2_BUF_TYPE_VIDEO_OVERLAY</constant>, and custom (driver -defined) types with code <constant>V4L2_BUF_TYPE_PRIVATE</constant> -and higher.</entry> - </row> - <row> - <entry>&v4l2-rect;</entry> - <entry><structfield>c</structfield></entry> - <entry>Cropping rectangle. The same co-ordinate system as -for &v4l2-cropcap; <structfield>bounds</structfield> is used.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>Cropping is not supported.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> - -<!-- -Local Variables: -mode: sgml -sgml-parent-document: "v4l2.sgml" -indent-tabs-mode: nil -End: ---> |