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diff --git a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml b/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml deleted file mode 100644 index 0aec62ed2bf8..000000000000 --- a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml +++ /dev/null @@ -1,706 +0,0 @@ - <title>Sliced VBI Data Interface</title> - - <para>VBI stands for Vertical Blanking Interval, a gap in the -sequence of lines of an analog video signal. During VBI no picture -information is transmitted, allowing some time while the electron beam -of a cathode ray tube TV returns to the top of the screen.</para> - - <para>Sliced VBI devices use hardware to demodulate data transmitted -in the VBI. V4L2 drivers shall <emphasis>not</emphasis> do this by -software, see also the <link linkend="raw-vbi">raw VBI -interface</link>. The data is passed as short packets of fixed size, -covering one scan line each. The number of packets per video frame is -variable.</para> - - <para>Sliced VBI capture and output devices are accessed through the -same character special files as raw VBI devices. When a driver -supports both interfaces, the default function of a -<filename>/dev/vbi</filename> device is <emphasis>raw</emphasis> VBI -capturing or output, and the sliced VBI function is only available -after calling the &VIDIOC-S-FMT; ioctl as defined below. Likewise a -<filename>/dev/video</filename> device may support the sliced VBI API, -however the default function here is video capturing or output. -Different file descriptors must be used to pass raw and sliced VBI -data simultaneously, if this is supported by the driver.</para> - - <section> - <title>Querying Capabilities</title> - - <para>Devices supporting the sliced VBI capturing or output API -set the <constant>V4L2_CAP_SLICED_VBI_CAPTURE</constant> or -<constant>V4L2_CAP_SLICED_VBI_OUTPUT</constant> flag respectively, in -the <structfield>capabilities</structfield> field of &v4l2-capability; -returned by the &VIDIOC-QUERYCAP; ioctl. At least one of the -read/write, streaming or asynchronous <link linkend="io">I/O -methods</link> must be supported. Sliced VBI devices may have a tuner -or modulator.</para> - </section> - - <section> - <title>Supplemental Functions</title> - - <para>Sliced VBI devices shall support <link linkend="video">video -input or output</link> and <link linkend="tuner">tuner or -modulator</link> ioctls if they have these capabilities, and they may -support <link linkend="control">control</link> ioctls. The <link -linkend="standard">video standard</link> ioctls provide information -vital to program a sliced VBI device, therefore must be -supported.</para> - </section> - - <section id="sliced-vbi-format-negotitation"> - <title>Sliced VBI Format Negotiation</title> - - <para>To find out which data services are supported by the -hardware applications can call the &VIDIOC-G-SLICED-VBI-CAP; ioctl. -All drivers implementing the sliced VBI interface must support this -ioctl. The results may differ from those of the &VIDIOC-S-FMT; ioctl -when the number of VBI lines the hardware can capture or output per -frame, or the number of services it can identify on a given line are -limited. For example on PAL line 16 the hardware may be able to look -for a VPS or Teletext signal, but not both at the same time.</para> - - <para>To determine the currently selected services applications -set the <structfield>type </structfield> field of &v4l2-format; to -<constant> V4L2_BUF_TYPE_SLICED_VBI_CAPTURE</constant> or <constant> -V4L2_BUF_TYPE_SLICED_VBI_OUTPUT</constant>, and the &VIDIOC-G-FMT; -ioctl fills the <structfield>fmt.sliced</structfield> member, a -&v4l2-sliced-vbi-format;.</para> - - <para>Applications can request different parameters by -initializing or modifying the <structfield>fmt.sliced</structfield> -member and calling the &VIDIOC-S-FMT; ioctl with a pointer to the -<structname>v4l2_format</structname> structure.</para> - - <para>The sliced VBI API is more complicated than the raw VBI API -because the hardware must be told which VBI service to expect on each -scan line. Not all services may be supported by the hardware on all -lines (this is especially true for VBI output where Teletext is often -unsupported and other services can only be inserted in one specific -line). In many cases, however, it is sufficient to just set the -<structfield>service_set</structfield> field to the required services -and let the driver fill the <structfield>service_lines</structfield> -array according to hardware capabilities. Only if more precise control -is needed should the programmer set the -<structfield>service_lines</structfield> array explicitly.</para> - - <para>The &VIDIOC-S-FMT; ioctl modifies the parameters -according to hardware capabilities. When the driver allocates -resources at this point, it may return an &EBUSY; if the required -resources are temporarily unavailable. Other resource allocation -points which may return <errorcode>EBUSY</errorcode> can be the -&VIDIOC-STREAMON; ioctl and the first &func-read;, &func-write; and -&func-select; call.</para> - - <table frame="none" pgwide="1" id="v4l2-sliced-vbi-format"> - <title>struct -<structname>v4l2_sliced_vbi_format</structname></title> - <tgroup cols="5"> - <colspec colname="c1" colwidth="3*" /> - <colspec colname="c2" colwidth="3*" /> - <colspec colname="c3" colwidth="2*" /> - <colspec colname="c4" colwidth="2*" /> - <colspec colname="c5" colwidth="2*" /> - <spanspec namest="c3" nameend="c5" spanname="hspan" /> - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>service_set</structfield></entry> - <entry spanname="hspan"><para>If -<structfield>service_set</structfield> is non-zero when passed with -&VIDIOC-S-FMT; or &VIDIOC-TRY-FMT;, the -<structfield>service_lines</structfield> array will be filled by the -driver according to the services specified in this field. For example, -if <structfield>service_set</structfield> is initialized with -<constant>V4L2_SLICED_TELETEXT_B | V4L2_SLICED_WSS_625</constant>, a -driver for the cx25840 video decoder sets lines 7-22 of both -fields<footnote><para>According to <link -linkend="ets300706">ETS 300 706</link> lines 6-22 of the -first field and lines 5-22 of the second field may carry Teletext -data.</para></footnote> to <constant>V4L2_SLICED_TELETEXT_B</constant> -and line 23 of the first field to -<constant>V4L2_SLICED_WSS_625</constant>. If -<structfield>service_set</structfield> is set to zero, then the values -of <structfield>service_lines</structfield> will be used instead. -</para><para>On return the driver sets this field to the union of all -elements of the returned <structfield>service_lines</structfield> -array. It may contain less services than requested, perhaps just one, -if the hardware cannot handle more services simultaneously. It may be -empty (zero) if none of the requested services are supported by the -hardware.</para></entry> - </row> - <row> - <entry>__u16</entry> - <entry><structfield>service_lines</structfield>[2][24]</entry> - <entry spanname="hspan"><para>Applications initialize this -array with sets of data services the driver shall look for or insert -on the respective scan line. Subject to hardware capabilities drivers -return the requested set, a subset, which may be just a single -service, or an empty set. When the hardware cannot handle multiple -services on the same line the driver shall choose one. No assumptions -can be made on which service the driver chooses.</para><para>Data -services are defined in <xref linkend="vbi-services2" />. Array indices -map to ITU-R line numbers (see also <xref linkend="vbi-525" /> and <xref - linkend="vbi-625" />) as follows: <!-- No nested -tables, sigh. --></para></entry> - </row> - <row> - <entry></entry> - <entry></entry> - <entry>Element</entry> - <entry>525 line systems</entry> - <entry>625 line systems</entry> - </row> - <row> - <entry></entry> - <entry></entry> - <entry><structfield>service_lines</structfield>[0][1]</entry> - <entry align="center">1</entry> - <entry align="center">1</entry> - </row> - <row> - <entry></entry> - <entry></entry> - <entry><structfield>service_lines</structfield>[0][23]</entry> - <entry align="center">23</entry> - <entry align="center">23</entry> - </row> - <row> - <entry></entry> - <entry></entry> - <entry><structfield>service_lines</structfield>[1][1]</entry> - <entry align="center">264</entry> - <entry align="center">314</entry> - </row> - <row> - <entry></entry> - <entry></entry> - <entry><structfield>service_lines</structfield>[1][23]</entry> - <entry align="center">286</entry> - <entry align="center">336</entry> - </row> - <!-- End of line numbers table. --> - <row> - <entry></entry> - <entry></entry> - <entry spanname="hspan">Drivers must set -<structfield>service_lines</structfield>[0][0] and -<structfield>service_lines</structfield>[1][0] to zero. -The <constant>V4L2_VBI_ITU_525_F1_START</constant>, -<constant>V4L2_VBI_ITU_525_F2_START</constant>, -<constant>V4L2_VBI_ITU_625_F1_START</constant> and -<constant>V4L2_VBI_ITU_625_F2_START</constant> defines give the start -line numbers for each field for each 525 or 625 line format as a -convenience. Don't forget that ITU line numbering starts at 1, not 0. -</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>io_size</structfield></entry> - <entry spanname="hspan">Maximum number of bytes passed by -one &func-read; or &func-write; call, and the buffer size in bytes for -the &VIDIOC-QBUF; and &VIDIOC-DQBUF; ioctl. Drivers set this field to -the size of &v4l2-sliced-vbi-data; times the number of non-zero -elements in the returned <structfield>service_lines</structfield> -array (that is the number of lines potentially carrying data).</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>reserved</structfield>[2]</entry> - <entry spanname="hspan">This array is reserved for future -extensions. Applications and drivers must set it to zero.</entry> - </row> - </tbody> - </tgroup> - </table> - - <!-- See also vidioc-g-sliced-vbi-cap.sgml --> - <table frame="none" pgwide="1" id="vbi-services2"> - <title>Sliced VBI services</title> - <tgroup cols="5"> - <colspec colname="c1" colwidth="2*" /> - <colspec colname="c2" colwidth="1*" /> - <colspec colname="c3" colwidth="1*" /> - <colspec colname="c4" colwidth="2*" /> - <colspec colname="c5" colwidth="2*" /> - <spanspec namest="c3" nameend="c5" spanname="rlp" /> - <thead> - <row> - <entry>Symbol</entry> - <entry>Value</entry> - <entry>Reference</entry> - <entry>Lines, usually</entry> - <entry>Payload</entry> - </row> - </thead> - <tbody valign="top"> - <row> - <entry><constant>V4L2_SLICED_TELETEXT_B</constant> -(Teletext System B)</entry> - <entry>0x0001</entry> - <entry><xref linkend="ets300706" />, <xref linkend="itu653" /></entry> - <entry>PAL/SECAM line 7-22, 320-335 (second field 7-22)</entry> - <entry>Last 42 of the 45 byte Teletext packet, that is -without clock run-in and framing code, lsb first transmitted.</entry> - </row> - <row> - <entry><constant>V4L2_SLICED_VPS</constant></entry> - <entry>0x0400</entry> - <entry><xref linkend="ets300231" /></entry> - <entry>PAL line 16</entry> - <entry>Byte number 3 to 15 according to Figure 9 of -ETS 300 231, lsb first transmitted.</entry> - </row> - <row> - <entry><constant>V4L2_SLICED_CAPTION_525</constant></entry> - <entry>0x1000</entry> - <entry><xref linkend="cea608" /></entry> - <entry>NTSC line 21, 284 (second field 21)</entry> - <entry>Two bytes in transmission order, including parity -bit, lsb first transmitted.</entry> - </row> - <row> - <entry><constant>V4L2_SLICED_WSS_625</constant></entry> - <entry>0x4000</entry> - <entry><xref linkend="itu1119" />, <xref linkend="en300294" /></entry> - <entry>PAL/SECAM line 23</entry> - <entry><screen> -Byte 0 1 - msb lsb msb lsb - Bit 7 6 5 4 3 2 1 0 x x 13 12 11 10 9 -</screen></entry> - </row> - <row> - <entry><constant>V4L2_SLICED_VBI_525</constant></entry> - <entry>0x1000</entry> - <entry spanname="rlp">Set of services applicable to 525 -line systems.</entry> - </row> - <row> - <entry><constant>V4L2_SLICED_VBI_625</constant></entry> - <entry>0x4401</entry> - <entry spanname="rlp">Set of services applicable to 625 -line systems.</entry> - </row> - </tbody> - </tgroup> - </table> - - <para>Drivers may return an &EINVAL; when applications attempt to -read or write data without prior format negotiation, after switching -the video standard (which may invalidate the negotiated VBI -parameters) and after switching the video input (which may change the -video standard as a side effect). The &VIDIOC-S-FMT; ioctl may return -an &EBUSY; when applications attempt to change the format while i/o is -in progress (between a &VIDIOC-STREAMON; and &VIDIOC-STREAMOFF; call, -and after the first &func-read; or &func-write; call).</para> - </section> - - <section> - <title>Reading and writing sliced VBI data</title> - - <para>A single &func-read; or &func-write; call must pass all data -belonging to one video frame. That is an array of -<structname>v4l2_sliced_vbi_data</structname> structures with one or -more elements and a total size not exceeding -<structfield>io_size</structfield> bytes. Likewise in streaming I/O -mode one buffer of <structfield>io_size</structfield> bytes must -contain data of one video frame. The <structfield>id</structfield> of -unused <structname>v4l2_sliced_vbi_data</structname> elements must be -zero.</para> - - <table frame="none" pgwide="1" id="v4l2-sliced-vbi-data"> - <title>struct -<structname>v4l2_sliced_vbi_data</structname></title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>id</structfield></entry> - <entry>A flag from <xref linkend="vbi-services" /> -identifying the type of data in this packet. Only a single bit must be -set. When the <structfield>id</structfield> of a captured packet is -zero, the packet is empty and the contents of other fields are -undefined. Applications shall ignore empty packets. When the -<structfield>id</structfield> of a packet for output is zero the -contents of the <structfield>data</structfield> field are undefined -and the driver must no longer insert data on the requested -<structfield>field</structfield> and -<structfield>line</structfield>.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>field</structfield></entry> - <entry>The video field number this data has been captured -from, or shall be inserted at. <constant>0</constant> for the first -field, <constant>1</constant> for the second field.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>line</structfield></entry> - <entry>The field (as opposed to frame) line number this -data has been captured from, or shall be inserted at. See <xref - linkend="vbi-525" /> and <xref linkend="vbi-625" /> for valid -values. Sliced VBI capture devices can set the line number of all -packets to <constant>0</constant> if the hardware cannot reliably -identify scan lines. The field number must always be valid.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>reserved</structfield></entry> - <entry>This field is reserved for future extensions. -Applications and drivers must set it to zero.</entry> - </row> - <row> - <entry>__u8</entry> - <entry><structfield>data</structfield>[48]</entry> - <entry>The packet payload. See <xref - linkend="vbi-services" /> for the contents and number of -bytes passed for each data type. The contents of padding bytes at the -end of this array are undefined, drivers and applications shall ignore -them.</entry> - </row> - </tbody> - </tgroup> - </table> - - <para>Packets are always passed in ascending line number order, -without duplicate line numbers. The &func-write; function and the -&VIDIOC-QBUF; ioctl must return an &EINVAL; when applications violate -this rule. They must also return an &EINVAL; when applications pass an -incorrect field or line number, or a combination of -<structfield>field</structfield>, <structfield>line</structfield> and -<structfield>id</structfield> which has not been negotiated with the -&VIDIOC-G-FMT; or &VIDIOC-S-FMT; ioctl. When the line numbers are -unknown the driver must pass the packets in transmitted order. The -driver can insert empty packets with <structfield>id</structfield> set -to zero anywhere in the packet array.</para> - - <para>To assure synchronization and to distinguish from frame -dropping, when a captured frame does not carry any of the requested -data services drivers must pass one or more empty packets. When an -application fails to pass VBI data in time for output, the driver -must output the last VPS and WSS packet again, and disable the output -of Closed Caption and Teletext data, or output data which is ignored -by Closed Caption and Teletext decoders.</para> - - <para>A sliced VBI device may support <link -linkend="rw">read/write</link> and/or streaming (<link -linkend="mmap">memory mapping</link> and/or <link linkend="userp">user -pointer</link>) I/O. The latter bears the possibility of synchronizing -video and VBI data by using buffer timestamps.</para> - - </section> - - <section> - <title>Sliced VBI Data in MPEG Streams</title> - - <para>If a device can produce an MPEG output stream, it may be -capable of providing <link -linkend="sliced-vbi-format-negotitation">negotiated sliced VBI -services</link> as data embedded in the MPEG stream. Users or -applications control this sliced VBI data insertion with the <link -linkend="v4l2-mpeg-stream-vbi-fmt">V4L2_CID_MPEG_STREAM_VBI_FMT</link> -control.</para> - - <para>If the driver does not provide the <link -linkend="v4l2-mpeg-stream-vbi-fmt">V4L2_CID_MPEG_STREAM_VBI_FMT</link> -control, or only allows that control to be set to <link -linkend="v4l2-mpeg-stream-vbi-fmt"><constant> -V4L2_MPEG_STREAM_VBI_FMT_NONE</constant></link>, then the device -cannot embed sliced VBI data in the MPEG stream.</para> - - <para>The <link linkend="v4l2-mpeg-stream-vbi-fmt"> -V4L2_CID_MPEG_STREAM_VBI_FMT</link> control does not implicitly set -the device driver to capture nor cease capturing sliced VBI data. The -control only indicates to embed sliced VBI data in the MPEG stream, if -an application has negotiated sliced VBI service be captured.</para> - - <para>It may also be the case that a device can embed sliced VBI -data in only certain types of MPEG streams: for example in an MPEG-2 -PS but not an MPEG-2 TS. In this situation, if sliced VBI data -insertion is requested, the sliced VBI data will be embedded in MPEG -stream types when supported, and silently omitted from MPEG stream -types where sliced VBI data insertion is not supported by the device. -</para> - - <para>The following subsections specify the format of the -embedded sliced VBI data.</para> - - <section> - <title>MPEG Stream Embedded, Sliced VBI Data Format: NONE</title> - <para>The <link linkend="v4l2-mpeg-stream-vbi-fmt"><constant> -V4L2_MPEG_STREAM_VBI_FMT_NONE</constant></link> embedded sliced VBI -format shall be interpreted by drivers as a control to cease -embedding sliced VBI data in MPEG streams. Neither the device nor -driver shall insert "empty" embedded sliced VBI data packets in the -MPEG stream when this format is set. No MPEG stream data structures -are specified for this format.</para> - </section> - - <section> - <title>MPEG Stream Embedded, Sliced VBI Data Format: IVTV</title> - <para>The <link linkend="v4l2-mpeg-stream-vbi-fmt"><constant> -V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant></link> embedded sliced VBI -format, when supported, indicates to the driver to embed up to 36 -lines of sliced VBI data per frame in an MPEG-2 <emphasis>Private -Stream 1 PES</emphasis> packet encapsulated in an MPEG-2 <emphasis> -Program Pack</emphasis> in the MPEG stream.</para> - - <para><emphasis>Historical context</emphasis>: This format -specification originates from a custom, embedded, sliced VBI data -format used by the <filename>ivtv</filename> driver. This format -has already been informally specified in the kernel sources in the -file <filename>Documentation/video4linux/cx2341x/README.vbi</filename> -. The maximum size of the payload and other aspects of this format -are driven by the CX23415 MPEG decoder's capabilities and limitations -with respect to extracting, decoding, and displaying sliced VBI data -embedded within an MPEG stream.</para> - - <para>This format's use is <emphasis>not</emphasis> exclusive to -the <filename>ivtv</filename> driver <emphasis>nor</emphasis> -exclusive to CX2341x devices, as the sliced VBI data packet insertion -into the MPEG stream is implemented in driver software. At least the -<filename>cx18</filename> driver provides sliced VBI data insertion -into an MPEG-2 PS in this format as well.</para> - - <para>The following definitions specify the payload of the -MPEG-2 <emphasis>Private Stream 1 PES</emphasis> packets that contain -sliced VBI data when <link linkend="v4l2-mpeg-stream-vbi-fmt"> -<constant>V4L2_MPEG_STREAM_VBI_FMT_IVTV</constant></link> is set. -(The MPEG-2 <emphasis>Private Stream 1 PES</emphasis> packet header -and encapsulating MPEG-2 <emphasis>Program Pack</emphasis> header are -not detailed here. Please refer to the MPEG-2 specifications for -details on those packet headers.)</para> - - <para>The payload of the MPEG-2 <emphasis>Private Stream 1 PES -</emphasis> packets that contain sliced VBI data is specified by -&v4l2-mpeg-vbi-fmt-ivtv;. The payload is variable -length, depending on the actual number of lines of sliced VBI data -present in a video frame. The payload may be padded at the end with -unspecified fill bytes to align the end of the payload to a 4-byte -boundary. The payload shall never exceed 1552 bytes (2 fields with -18 lines/field with 43 bytes of data/line and a 4 byte magic number). -</para> - - <table frame="none" pgwide="1" id="v4l2-mpeg-vbi-fmt-ivtv"> - <title>struct <structname>v4l2_mpeg_vbi_fmt_ivtv</structname> - </title> - <tgroup cols="4"> - &cs-ustr; - <tbody valign="top"> - <row> - <entry>__u8</entry> - <entry><structfield>magic</structfield>[4]</entry> - <entry></entry> - <entry>A "magic" constant from <xref - linkend="v4l2-mpeg-vbi-fmt-ivtv-magic" /> that indicates -this is a valid sliced VBI data payload and also indicates which -member of the anonymous union, <structfield>itv0</structfield> or -<structfield>ITV0</structfield>, to use for the payload data.</entry> - </row> - <row> - <entry>union</entry> - <entry>(anonymous)</entry> - </row> - <row> - <entry></entry> - <entry>struct <link linkend="v4l2-mpeg-vbi-itv0"> - <structname>v4l2_mpeg_vbi_itv0</structname></link> - </entry> - <entry><structfield>itv0</structfield></entry> - <entry>The primary form of the sliced VBI data payload -that contains anywhere from 1 to 35 lines of sliced VBI data. -Line masks are provided in this form of the payload indicating -which VBI lines are provided.</entry> - </row> - <row> - <entry></entry> - <entry>struct <link linkend="v4l2-mpeg-vbi-itv0-1"> - <structname>v4l2_mpeg_vbi_ITV0</structname></link> - </entry> - <entry><structfield>ITV0</structfield></entry> - <entry>An alternate form of the sliced VBI data payload -used when 36 lines of sliced VBI data are present. No line masks are -provided in this form of the payload; all valid line mask bits are -implcitly set.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-mpeg-vbi-fmt-ivtv-magic"> - <title>Magic Constants for &v4l2-mpeg-vbi-fmt-ivtv; - <structfield>magic</structfield> field</title> - <tgroup cols="3"> - &cs-def; - <thead> - <row> - <entry align="left">Defined Symbol</entry> - <entry align="left">Value</entry> - <entry align="left">Description</entry> - </row> - </thead> - <tbody valign="top"> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_MAGIC0</constant> - </entry> - <entry>"itv0"</entry> - <entry>Indicates the <structfield>itv0</structfield> -member of the union in &v4l2-mpeg-vbi-fmt-ivtv; is valid.</entry> - </row> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_MAGIC1</constant> - </entry> - <entry>"ITV0"</entry> - <entry>Indicates the <structfield>ITV0</structfield> -member of the union in &v4l2-mpeg-vbi-fmt-ivtv; is valid and -that 36 lines of sliced VBI data are present.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-mpeg-vbi-itv0"> - <title>struct <structname>v4l2_mpeg_vbi_itv0</structname> - </title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__le32</entry> - <entry><structfield>linemask</structfield>[2]</entry> - <entry><para>Bitmasks indicating the VBI service lines -present. These <structfield>linemask</structfield> values are stored -in little endian byte order in the MPEG stream. Some reference -<structfield>linemask</structfield> bit positions with their -corresponding VBI line number and video field are given below. -b<subscript>0</subscript> indicates the least significant bit of a -<structfield>linemask</structfield> value:<screen> -<structfield>linemask</structfield>[0] b<subscript>0</subscript>: line 6 first field -<structfield>linemask</structfield>[0] b<subscript>17</subscript>: line 23 first field -<structfield>linemask</structfield>[0] b<subscript>18</subscript>: line 6 second field -<structfield>linemask</structfield>[0] b<subscript>31</subscript>: line 19 second field -<structfield>linemask</structfield>[1] b<subscript>0</subscript>: line 20 second field -<structfield>linemask</structfield>[1] b<subscript>3</subscript>: line 23 second field -<structfield>linemask</structfield>[1] b<subscript>4</subscript>-b<subscript>31</subscript>: unused and set to 0</screen></para></entry> - </row> - <row> - <entry>struct <link linkend="v4l2-mpeg-vbi-itv0-line"> - <structname>v4l2_mpeg_vbi_itv0_line</structname></link> - </entry> - <entry><structfield>line</structfield>[35]</entry> - <entry>This is a variable length array that holds from 1 -to 35 lines of sliced VBI data. The sliced VBI data lines present -correspond to the bits set in the <structfield>linemask</structfield> -array, starting from b<subscript>0</subscript> of <structfield> -linemask</structfield>[0] up through b<subscript>31</subscript> of -<structfield>linemask</structfield>[0], and from b<subscript>0 -</subscript> of <structfield>linemask</structfield>[1] up through b -<subscript>3</subscript> of <structfield>linemask</structfield>[1]. -<structfield>line</structfield>[0] corresponds to the first bit -found set in the <structfield>linemask</structfield> array, -<structfield>line</structfield>[1] corresponds to the second bit -found set in the <structfield>linemask</structfield> array, etc. -If no <structfield>linemask</structfield> array bits are set, then -<structfield>line</structfield>[0] may contain one line of -unspecified data that should be ignored by applications.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-mpeg-vbi-itv0-1"> - <title>struct <structname>v4l2_mpeg_vbi_ITV0</structname> - </title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>struct <link linkend="v4l2-mpeg-vbi-itv0-line"> - <structname>v4l2_mpeg_vbi_itv0_line</structname></link> - </entry> - <entry><structfield>line</structfield>[36]</entry> - <entry>A fixed length array of 36 lines of sliced VBI -data. <structfield>line</structfield>[0] through <structfield>line -</structfield>[17] correspond to lines 6 through 23 of the -first field. <structfield>line</structfield>[18] through -<structfield>line</structfield>[35] corresponds to lines 6 -through 23 of the second field.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-mpeg-vbi-itv0-line"> - <title>struct <structname>v4l2_mpeg_vbi_itv0_line</structname> - </title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u8</entry> - <entry><structfield>id</structfield></entry> - <entry>A line identifier value from -<xref linkend="ITV0-Line-Identifier-Constants" /> that indicates -the type of sliced VBI data stored on this line.</entry> - </row> - <row> - <entry>__u8</entry> - <entry><structfield>data</structfield>[42]</entry> - <entry>The sliced VBI data for the line.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="ITV0-Line-Identifier-Constants"> - <title>Line Identifiers for struct <link - linkend="v4l2-mpeg-vbi-itv0-line"><structname> -v4l2_mpeg_vbi_itv0_line</structname></link> <structfield>id -</structfield> field</title> - <tgroup cols="3"> - &cs-def; - <thead> - <row> - <entry align="left">Defined Symbol</entry> - <entry align="left">Value</entry> - <entry align="left">Description</entry> - </row> - </thead> - <tbody valign="top"> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_TELETEXT_B</constant> - </entry> - <entry>1</entry> - <entry>Refer to <link linkend="vbi-services2"> -Sliced VBI services</link> for a description of the line payload.</entry> - </row> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_CAPTION_525</constant> - </entry> - <entry>4</entry> - <entry>Refer to <link linkend="vbi-services2"> -Sliced VBI services</link> for a description of the line payload.</entry> - </row> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_WSS_625</constant> - </entry> - <entry>5</entry> - <entry>Refer to <link linkend="vbi-services2"> -Sliced VBI services</link> for a description of the line payload.</entry> - </row> - <row> - <entry><constant>V4L2_MPEG_VBI_IVTV_VPS</constant> - </entry> - <entry>7</entry> - <entry>Refer to <link linkend="vbi-services2"> -Sliced VBI services</link> for a description of the line payload.</entry> - </row> - </tbody> - </tgroup> - </table> - - </section> - </section> |