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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-enumstd.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-enumstd.xml b/Documentation/DocBook/media/v4l/vidioc-enumstd.xml new file mode 100644 index 00000000..3a5fc540 --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-enumstd.xml @@ -0,0 +1,383 @@ +<refentry id="vidioc-enumstd"> + <refmeta> + <refentrytitle>ioctl VIDIOC_ENUMSTD</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_ENUMSTD</refname> + <refpurpose>Enumerate supported video standards</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_standard *<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_ENUMSTD</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para>To query the attributes of a video standard, +especially a custom (driver defined) one, applications initialize the +<structfield>index</structfield> field of &v4l2-standard; and call the +<constant>VIDIOC_ENUMSTD</constant> ioctl with a pointer to this +structure. Drivers fill the rest of the structure or return an +&EINVAL; when the index is out of bounds. To enumerate all standards +applications shall begin at index zero, incrementing by one until the +driver returns <errorcode>EINVAL</errorcode>. Drivers may enumerate a +different set of standards after switching the video input or +output.<footnote> + <para>The supported standards may overlap and we need an +unambiguous set to find the current standard returned by +<constant>VIDIOC_G_STD</constant>.</para> + </footnote></para> + + <table pgwide="1" frame="none" id="v4l2-standard"> + <title>struct <structname>v4l2_standard</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>index</structfield></entry> + <entry>Number of the video standard, set by the +application.</entry> + </row> + <row> + <entry>&v4l2-std-id;</entry> + <entry><structfield>id</structfield></entry> + <entry>The bits in this field identify the standard as +one of the common standards listed in <xref linkend="v4l2-std-id" />, +or if bits 32 to 63 are set as custom standards. Multiple bits can be +set if the hardware does not distinguish between these standards, +however separate indices do not indicate the opposite. The +<structfield>id</structfield> must be unique. No other enumerated +<structname>v4l2_standard</structname> structure, for this input or +output anyway, can contain the same set of bits.</entry> + </row> + <row> + <entry>__u8</entry> + <entry><structfield>name</structfield>[24]</entry> + <entry>Name of the standard, a NUL-terminated ASCII +string, for example: "PAL-B/G", "NTSC Japan". This information is +intended for the user.</entry> + </row> + <row> + <entry>&v4l2-fract;</entry> + <entry><structfield>frameperiod</structfield></entry> + <entry>The frame period (not field period) is numerator +/ denominator. For example M/NTSC has a frame period of 1001 / +30000 seconds.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>framelines</structfield></entry> + <entry>Total lines per frame including blanking, +e. g. 625 for B/PAL.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[4]</entry> + <entry>Reserved for future extensions. Drivers must set +the array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="v4l2-fract"> + <title>struct <structname>v4l2_fract</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>numerator</structfield></entry> + <entry></entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>denominator</structfield></entry> + <entry></entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="v4l2-std-id"> + <title>typedef <structname>v4l2_std_id</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u64</entry> + <entry><structfield>v4l2_std_id</structfield></entry> + <entry>This type is a set, each bit representing another +video standard as listed below and in <xref +linkend="video-standards" />. The 32 most significant bits are reserved +for custom (driver defined) video standards.</entry> + </row> + </tbody> + </tgroup> + </table> + + <para><programlisting> +#define V4L2_STD_PAL_B ((v4l2_std_id)0x00000001) +#define V4L2_STD_PAL_B1 ((v4l2_std_id)0x00000002) +#define V4L2_STD_PAL_G ((v4l2_std_id)0x00000004) +#define V4L2_STD_PAL_H ((v4l2_std_id)0x00000008) +#define V4L2_STD_PAL_I ((v4l2_std_id)0x00000010) +#define V4L2_STD_PAL_D ((v4l2_std_id)0x00000020) +#define V4L2_STD_PAL_D1 ((v4l2_std_id)0x00000040) +#define V4L2_STD_PAL_K ((v4l2_std_id)0x00000080) + +#define V4L2_STD_PAL_M ((v4l2_std_id)0x00000100) +#define V4L2_STD_PAL_N ((v4l2_std_id)0x00000200) +#define V4L2_STD_PAL_Nc ((v4l2_std_id)0x00000400) +#define V4L2_STD_PAL_60 ((v4l2_std_id)0x00000800) +</programlisting></para><para><constant>V4L2_STD_PAL_60</constant> is +a hybrid standard with 525 lines, 60 Hz refresh rate, and PAL color +modulation with a 4.43 MHz color subcarrier. Some PAL video recorders +can play back NTSC tapes in this mode for display on a 50/60 Hz agnostic +PAL TV.</para><para><programlisting> +#define V4L2_STD_NTSC_M ((v4l2_std_id)0x00001000) +#define V4L2_STD_NTSC_M_JP ((v4l2_std_id)0x00002000) +#define V4L2_STD_NTSC_443 ((v4l2_std_id)0x00004000) +</programlisting></para><para><constant>V4L2_STD_NTSC_443</constant> +is a hybrid standard with 525 lines, 60 Hz refresh rate, and NTSC +color modulation with a 4.43 MHz color +subcarrier.</para><para><programlisting> +#define V4L2_STD_NTSC_M_KR ((v4l2_std_id)0x00008000) + +#define V4L2_STD_SECAM_B ((v4l2_std_id)0x00010000) +#define V4L2_STD_SECAM_D ((v4l2_std_id)0x00020000) +#define V4L2_STD_SECAM_G ((v4l2_std_id)0x00040000) +#define V4L2_STD_SECAM_H ((v4l2_std_id)0x00080000) +#define V4L2_STD_SECAM_K ((v4l2_std_id)0x00100000) +#define V4L2_STD_SECAM_K1 ((v4l2_std_id)0x00200000) +#define V4L2_STD_SECAM_L ((v4l2_std_id)0x00400000) +#define V4L2_STD_SECAM_LC ((v4l2_std_id)0x00800000) + +/* ATSC/HDTV */ +#define V4L2_STD_ATSC_8_VSB ((v4l2_std_id)0x01000000) +#define V4L2_STD_ATSC_16_VSB ((v4l2_std_id)0x02000000) +</programlisting></para><para><!-- ATSC proposal by Mark McClelland, +video4linux-list@redhat.com on 17 Oct 2002 +--><constant>V4L2_STD_ATSC_8_VSB</constant> and +<constant>V4L2_STD_ATSC_16_VSB</constant> are U.S. terrestrial digital +TV standards. Presently the V4L2 API does not support digital TV. See +also the Linux DVB API at <ulink +url="http://linuxtv.org">http://linuxtv.org</ulink>.</para> +<para><programlisting> +#define V4L2_STD_PAL_BG (V4L2_STD_PAL_B |\ + V4L2_STD_PAL_B1 |\ + V4L2_STD_PAL_G) +#define V4L2_STD_B (V4L2_STD_PAL_B |\ + V4L2_STD_PAL_B1 |\ + V4L2_STD_SECAM_B) +#define V4L2_STD_GH (V4L2_STD_PAL_G |\ + V4L2_STD_PAL_H |\ + V4L2_STD_SECAM_G |\ + V4L2_STD_SECAM_H) +#define V4L2_STD_PAL_DK (V4L2_STD_PAL_D |\ + V4L2_STD_PAL_D1 |\ + V4L2_STD_PAL_K) +#define V4L2_STD_PAL (V4L2_STD_PAL_BG |\ + V4L2_STD_PAL_DK |\ + V4L2_STD_PAL_H |\ + V4L2_STD_PAL_I) +#define V4L2_STD_NTSC (V4L2_STD_NTSC_M |\ + V4L2_STD_NTSC_M_JP |\ + V4L2_STD_NTSC_M_KR) +#define V4L2_STD_MN (V4L2_STD_PAL_M |\ + V4L2_STD_PAL_N |\ + V4L2_STD_PAL_Nc |\ + V4L2_STD_NTSC) +#define V4L2_STD_SECAM_DK (V4L2_STD_SECAM_D |\ + V4L2_STD_SECAM_K |\ + V4L2_STD_SECAM_K1) +#define V4L2_STD_DK (V4L2_STD_PAL_DK |\ + V4L2_STD_SECAM_DK) + +#define V4L2_STD_SECAM (V4L2_STD_SECAM_B |\ + V4L2_STD_SECAM_G |\ + V4L2_STD_SECAM_H |\ + V4L2_STD_SECAM_DK |\ + V4L2_STD_SECAM_L |\ + V4L2_STD_SECAM_LC) + +#define V4L2_STD_525_60 (V4L2_STD_PAL_M |\ + V4L2_STD_PAL_60 |\ + V4L2_STD_NTSC |\ + V4L2_STD_NTSC_443) +#define V4L2_STD_625_50 (V4L2_STD_PAL |\ + V4L2_STD_PAL_N |\ + V4L2_STD_PAL_Nc |\ + V4L2_STD_SECAM) + +#define V4L2_STD_UNKNOWN 0 +#define V4L2_STD_ALL (V4L2_STD_525_60 |\ + V4L2_STD_625_50) +</programlisting></para> + + <table pgwide="1" id="video-standards" orient="land"> + <title>Video Standards (based on [<xref linkend="itu470" />])</title> + <tgroup cols="12" colsep="1" rowsep="1" align="center"> + <colspec colname="c1" align="left" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <colspec colnum="7" colname="c7" /> + <colspec colnum="9" colname="c9" /> + <colspec colnum="12" colname="c12" /> + <spanspec namest="c2" nameend="c3" spanname="m" align="center" /> + <spanspec namest="c4" nameend="c12" spanname="x" align="center" /> + <spanspec namest="c5" nameend="c7" spanname="b" align="center" /> + <spanspec namest="c9" nameend="c12" spanname="s" align="center" /> + <thead> + <row> + <entry>Characteristics</entry> + <entry><para>M/NTSC<footnote><para>Japan uses a standard +similar to M/NTSC +(V4L2_STD_NTSC_M_JP).</para></footnote></para></entry> + <entry>M/PAL</entry> + <entry><para>N/PAL<footnote><para> The values in +brackets apply to the combination N/PAL a.k.a. +N<subscript>C</subscript> used in Argentina +(V4L2_STD_PAL_Nc).</para></footnote></para></entry> + <entry align="center">B, B1, G/PAL</entry> + <entry align="center">D, D1, K/PAL</entry> + <entry align="center">H/PAL</entry> + <entry align="center">I/PAL</entry> + <entry align="center">B, G/SECAM</entry> + <entry align="center">D, K/SECAM</entry> + <entry align="center">K1/SECAM</entry> + <entry align="center">L/SECAM</entry> + </row> + </thead> + <tbody valign="top"> + <row> + <entry>Frame lines</entry> + <entry spanname="m">525</entry> + <entry spanname="x">625</entry> + </row> + <row> + <entry>Frame period (s)</entry> + <entry spanname="m">1001/30000</entry> + <entry spanname="x">1/25</entry> + </row> + <row> + <entry>Chrominance sub-carrier frequency (Hz)</entry> + <entry>3579545 ± 10</entry> + <entry>3579611.49 ± 10</entry> + <entry>4433618.75 ± 5 (3582056.25 +± 5)</entry> + <entry spanname="b">4433618.75 ± 5</entry> + <entry>4433618.75 ± 1</entry> + <entry spanname="s">f<subscript>OR</subscript> = +4406250 ± 2000, f<subscript>OB</subscript> = 4250000 +± 2000</entry> + </row> + <row> + <entry>Nominal radio-frequency channel bandwidth +(MHz)</entry> + <entry>6</entry> + <entry>6</entry> + <entry>6</entry> + <entry>B: 7; B1, G: 8</entry> + <entry>8</entry> + <entry>8</entry> + <entry>8</entry> + <entry>8</entry> + <entry>8</entry> + <entry>8</entry> + <entry>8</entry> + </row> + <row> + <entry>Sound carrier relative to vision carrier +(MHz)</entry> + <entry>+ 4.5</entry> + <entry>+ 4.5</entry> + <entry>+ 4.5</entry> + <entry><para>+ 5.5 ± 0.001 +<footnote><para>In the Federal Republic of Germany, Austria, Italy, +the Netherlands, Slovakia and Switzerland a system of two sound +carriers is used, the frequency of the second carrier being +242.1875 kHz above the frequency of the first sound carrier. For +stereophonic sound transmissions a similar system is used in +Australia.</para></footnote> <footnote><para>New Zealand uses a sound +carrier displaced 5.4996 ± 0.0005 MHz from the vision +carrier.</para></footnote> <footnote><para>In Denmark, Finland, New +Zealand, Sweden and Spain a system of two sound carriers is used. In +Iceland, Norway and Poland the same system is being introduced. The +second carrier is 5.85 MHz above the vision carrier and is DQPSK +modulated with 728 kbit/s sound and data multiplex. (NICAM +system)</para></footnote> <footnote><para>In the United Kingdom, a +system of two sound carriers is used. The second sound carrier is +6.552 MHz above the vision carrier and is DQPSK modulated with a +728 kbit/s sound and data multiplex able to carry two sound +channels. (NICAM system)</para></footnote></para></entry> + <entry>+ 6.5 ± 0.001</entry> + <entry>+ 5.5</entry> + <entry>+ 5.9996 ± 0.0005</entry> + <entry>+ 5.5 ± 0.001</entry> + <entry>+ 6.5 ± 0.001</entry> + <entry>+ 6.5</entry> + <entry><para>+ 6.5 <footnote><para>In France, a +digital carrier 5.85 MHz away from the vision carrier may be used in +addition to the main sound carrier. It is modulated in differentially +encoded QPSK with a 728 kbit/s sound and data multiplexer capable of +carrying two sound channels. (NICAM +system)</para></footnote></para></entry> + </row> + </tbody> + </tgroup> + </table> + </refsect1> + + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>EINVAL</errorcode></term> + <listitem> + <para>The &v4l2-standard; <structfield>index</structfield> +is out of bounds.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> |