Based on kernel version 4.7.2. Page generated on 2016-08-22 22:45 EST.
1 <refentry id="vidioc-g-std"> 2 <refmeta> 3 <refentrytitle>ioctl VIDIOC_G_STD, VIDIOC_S_STD</refentrytitle> 4 &manvol; 5 </refmeta> 6 7 <refnamediv> 8 <refname>VIDIOC_G_STD</refname> 9 <refname>VIDIOC_S_STD</refname> 10 <refpurpose>Query or select the video standard of the current input</refpurpose> 11 </refnamediv> 12 13 <refsynopsisdiv> 14 <funcsynopsis> 15 <funcprototype> 16 <funcdef>int <function>ioctl</function></funcdef> 17 <paramdef>int <parameter>fd</parameter></paramdef> 18 <paramdef>int <parameter>request</parameter></paramdef> 19 <paramdef>v4l2_std_id 20 *<parameter>argp</parameter></paramdef> 21 </funcprototype> 22 </funcsynopsis> 23 <funcsynopsis> 24 <funcprototype> 25 <funcdef>int <function>ioctl</function></funcdef> 26 <paramdef>int <parameter>fd</parameter></paramdef> 27 <paramdef>int <parameter>request</parameter></paramdef> 28 <paramdef>const v4l2_std_id 29 *<parameter>argp</parameter></paramdef> 30 </funcprototype> 31 </funcsynopsis> 32 </refsynopsisdiv> 33 34 <refsect1> 35 <title>Arguments</title> 36 37 <variablelist> 38 <varlistentry> 39 <term><parameter>fd</parameter></term> 40 <listitem> 41 <para>&fd;</para> 42 </listitem> 43 </varlistentry> 44 <varlistentry> 45 <term><parameter>request</parameter></term> 46 <listitem> 47 <para>VIDIOC_G_STD, VIDIOC_S_STD</para> 48 </listitem> 49 </varlistentry> 50 <varlistentry> 51 <term><parameter>argp</parameter></term> 52 <listitem> 53 <para></para> 54 </listitem> 55 </varlistentry> 56 </variablelist> 57 </refsect1> 58 59 <refsect1> 60 <title>Description</title> 61 62 <para>To query and select the current video standard applications 63 use the <constant>VIDIOC_G_STD</constant> and <constant>VIDIOC_S_STD</constant> ioctls which take a pointer to a 64 &v4l2-std-id; type as argument. <constant>VIDIOC_G_STD</constant> can 65 return a single flag or a set of flags as in &v4l2-standard; field 66 <structfield>id</structfield>. The flags must be unambiguous such 67 that they appear in only one enumerated <structname>v4l2_standard</structname> structure.</para> 68 69 <para><constant>VIDIOC_S_STD</constant> accepts one or more 70 flags, being a write-only ioctl it does not return the actual new standard as 71 <constant>VIDIOC_G_STD</constant> does. When no flags are given or 72 the current input does not support the requested standard the driver 73 returns an &EINVAL;. When the standard set is ambiguous drivers may 74 return <errorcode>EINVAL</errorcode> or choose any of the requested 75 standards. If the current input or output does not support standard video timings (e.g. if 76 &VIDIOC-ENUMINPUT; does not set the <constant>V4L2_IN_CAP_STD</constant> flag), then 77 &ENODATA; is returned.</para> 78 </refsect1> 79 80 <refsect1> 81 &return-value; 82 83 <variablelist> 84 <varlistentry> 85 <term><errorcode>EINVAL</errorcode></term> 86 <listitem> 87 <para>The <constant>VIDIOC_S_STD</constant> parameter was unsuitable.</para> 88 </listitem> 89 </varlistentry> 90 <varlistentry> 91 <term><errorcode>ENODATA</errorcode></term> 92 <listitem> 93 <para>Standard video timings are not supported for this input or output.</para> 94 </listitem> 95 </varlistentry> 96 </variablelist> 97 </refsect1> 98 </refentry>
