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diff --git a/Documentation/media/uapi/v4l/dev-sliced-vbi.rst b/Documentation/media/uapi/v4l/dev-sliced-vbi.rst deleted file mode 100644 index e86346f66017..000000000000 --- a/Documentation/media/uapi/v4l/dev-sliced-vbi.rst +++ /dev/null @@ -1,672 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -.. _sliced: - -************************* -Sliced VBI Data Interface -************************* - -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. - -Sliced VBI devices use hardware to demodulate data transmitted in the -VBI. V4L2 drivers shall *not* do this by software, see also the -:ref:`raw VBI interface <raw-vbi>`. The data is passed as short -packets of fixed size, covering one scan line each. The number of -packets per video frame is variable. - -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 ``/dev/vbi`` device is *raw* VBI -capturing or output, and the sliced VBI function is only available after -calling the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl as defined -below. Likewise a ``/dev/video`` 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. - - -Querying Capabilities -===================== - -Devices supporting the sliced VBI capturing or output API set the -``V4L2_CAP_SLICED_VBI_CAPTURE`` or ``V4L2_CAP_SLICED_VBI_OUTPUT`` flag -respectively, in the ``capabilities`` field of struct -:c:type:`v4l2_capability` returned by the -:ref:`VIDIOC_QUERYCAP` ioctl. At least one of the -read/write, streaming or asynchronous :ref:`I/O methods <io>` must be -supported. Sliced VBI devices may have a tuner or modulator. - - -Supplemental Functions -====================== - -Sliced VBI devices shall support :ref:`video input or output <video>` -and :ref:`tuner or modulator <tuner>` ioctls if they have these -capabilities, and they may support :ref:`control` ioctls. -The :ref:`video standard <standard>` ioctls provide information vital -to program a sliced VBI device, therefore must be supported. - - -.. _sliced-vbi-format-negotitation: - -Sliced VBI Format Negotiation -============================= - -To find out which data services are supported by the hardware -applications can call the -:ref:`VIDIOC_G_SLICED_VBI_CAP <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 -:ref:`VIDIOC_S_FMT <VIDIOC_G_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. - -To determine the currently selected services applications set the -``type`` field of struct :c:type:`v4l2_format` to -``V4L2_BUF_TYPE_SLICED_VBI_CAPTURE`` or -``V4L2_BUF_TYPE_SLICED_VBI_OUTPUT``, and the -:ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` ioctl fills the ``fmt.sliced`` -member, a struct -:c:type:`v4l2_sliced_vbi_format`. - -Applications can request different parameters by initializing or -modifying the ``fmt.sliced`` member and calling the -:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl with a pointer to the -struct :c:type:`v4l2_format` structure. - -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 ``service_set`` field -to the required services and let the driver fill the ``service_lines`` -array according to hardware capabilities. Only if more precise control -is needed should the programmer set the ``service_lines`` array -explicitly. - -The :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl modifies the parameters -according to hardware capabilities. When the driver allocates resources -at this point, it may return an ``EBUSY`` error code if the required -resources are temporarily unavailable. Other resource allocation points -which may return ``EBUSY`` can be the -:ref:`VIDIOC_STREAMON` ioctl and the first -:ref:`read() <func-read>`, :ref:`write() <func-write>` and -:ref:`select() <func-select>` call. - - -.. c:type:: v4l2_sliced_vbi_format - -struct v4l2_sliced_vbi_format ------------------------------ - -.. raw:: latex - - \begingroup - \scriptsize - \setlength{\tabcolsep}{2pt} - -.. tabularcolumns:: |p{.85cm}|p{3.3cm}|p{4.4cm}|p{4.4cm}|p{4.4cm}| - -.. cssclass:: longtable - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 3 3 2 2 2 - - * - __u32 - - ``service_set`` - - :cspan:`2` - - If ``service_set`` is non-zero when passed with - :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` or - :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>`, the ``service_lines`` - array will be filled by the driver according to the services - specified in this field. For example, if ``service_set`` is - initialized with ``V4L2_SLICED_TELETEXT_B | V4L2_SLICED_WSS_625``, - a driver for the cx25840 video decoder sets lines 7-22 of both - fields [#f1]_ to ``V4L2_SLICED_TELETEXT_B`` and line 23 of the first - field to ``V4L2_SLICED_WSS_625``. If ``service_set`` is set to - zero, then the values of ``service_lines`` will be used instead. - - On return the driver sets this field to the union of all elements - of the returned ``service_lines`` 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. - * - __u16 - - ``service_lines``\ [2][24] - - :cspan:`2` - - 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. - - Data services are defined in :ref:`vbi-services2`. Array indices - map to ITU-R line numbers\ [#f2]_ as follows: - * - - - - - Element - - 525 line systems - - 625 line systems - * - - - - - ``service_lines``\ [0][1] - - 1 - - 1 - * - - - - - ``service_lines``\ [0][23] - - 23 - - 23 - * - - - - - ``service_lines``\ [1][1] - - 264 - - 314 - * - - - - - ``service_lines``\ [1][23] - - 286 - - 336 - * - - - - - :cspan:`2` Drivers must set ``service_lines`` [0][0] and - ``service_lines``\ [1][0] to zero. The - ``V4L2_VBI_ITU_525_F1_START``, ``V4L2_VBI_ITU_525_F2_START``, - ``V4L2_VBI_ITU_625_F1_START`` and ``V4L2_VBI_ITU_625_F2_START`` - 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. - * - __u32 - - ``io_size`` - - :cspan:`2` Maximum number of bytes passed by one - :ref:`read() <func-read>` or :ref:`write() <func-write>` call, - and the buffer size in bytes for the - :ref:`VIDIOC_QBUF` and - :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` ioctl. Drivers set this field - to the size of struct - :c:type:`v4l2_sliced_vbi_data` times the - number of non-zero elements in the returned ``service_lines`` - array (that is the number of lines potentially carrying data). - * - __u32 - - ``reserved``\ [2] - - :cspan:`2` This array is reserved for future extensions. - - Applications and drivers must set it to zero. - -.. raw:: latex - - \endgroup - -.. _vbi-services2: - -Sliced VBI services -------------------- - -.. raw:: latex - - \scriptsize - -.. tabularcolumns:: |p{4.1cm}|p{1.1cm}|p{2.4cm}|p{2.0cm}|p{7.3cm}| - -.. flat-table:: - :header-rows: 1 - :stub-columns: 0 - :widths: 2 1 1 2 2 - - * - Symbol - - Value - - Reference - - Lines, usually - - Payload - * - ``V4L2_SLICED_TELETEXT_B`` (Teletext System B) - - 0x0001 - - :ref:`ets300706`, - - :ref:`itu653` - - PAL/SECAM line 7-22, 320-335 (second field 7-22) - - Last 42 of the 45 byte Teletext packet, that is without clock - run-in and framing code, lsb first transmitted. - * - ``V4L2_SLICED_VPS`` - - 0x0400 - - :ref:`ets300231` - - PAL line 16 - - Byte number 3 to 15 according to Figure 9 of ETS 300 231, lsb - first transmitted. - * - ``V4L2_SLICED_CAPTION_525`` - - 0x1000 - - :ref:`cea608` - - NTSC line 21, 284 (second field 21) - - Two bytes in transmission order, including parity bit, lsb first - transmitted. - * - ``V4L2_SLICED_WSS_625`` - - 0x4000 - - :ref:`itu1119`, - - :ref:`en300294` - - PAL/SECAM line 23 - - - - :: - - Byte 0 1 - msb lsb msb lsb - Bit 7 6 5 4 3 2 1 0 x x 13 12 11 10 9 - * - ``V4L2_SLICED_VBI_525`` - - 0x1000 - - :cspan:`2` Set of services applicable to 525 line systems. - * - ``V4L2_SLICED_VBI_625`` - - 0x4401 - - :cspan:`2` Set of services applicable to 625 line systems. - -.. raw:: latex - - \normalsize - - -Drivers may return an ``EINVAL`` error code 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 :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl may -return an ``EBUSY`` error code when applications attempt to change the -format while i/o is in progress (between a -:ref:`VIDIOC_STREAMON` and -:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` call, and after the first -:ref:`read() <func-read>` or :ref:`write() <func-write>` call). - - -Reading and writing sliced VBI data -=================================== - -A single :ref:`read() <func-read>` or :ref:`write() <func-write>` -call must pass all data belonging to one video frame. That is an array -of struct :c:type:`v4l2_sliced_vbi_data` structures with one or -more elements and a total size not exceeding ``io_size`` bytes. Likewise -in streaming I/O mode one buffer of ``io_size`` bytes must contain data -of one video frame. The ``id`` of unused -struct :c:type:`v4l2_sliced_vbi_data` elements must be zero. - - -.. c:type:: v4l2_sliced_vbi_data - -struct v4l2_sliced_vbi_data ---------------------------- - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 3 1 4 - - * - __u32 - - ``id`` - - A flag from :ref:`vbi-services` identifying the type of data in - this packet. Only a single bit must be set. When the ``id`` 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 ``id`` of a packet for output is zero the - contents of the ``data`` field are undefined and the driver must - no longer insert data on the requested ``field`` and ``line``. - * - __u32 - - ``field`` - - The video field number this data has been captured from, or shall - be inserted at. ``0`` for the first field, ``1`` for the second - field. - * - __u32 - - ``line`` - - The field (as opposed to frame) line number this data has been - captured from, or shall be inserted at. See :ref:`vbi-525` and - :ref:`vbi-625` for valid values. Sliced VBI capture devices can - set the line number of all packets to ``0`` if the hardware cannot - reliably identify scan lines. The field number must always be - valid. - * - __u32 - - ``reserved`` - - This field is reserved for future extensions. Applications and - drivers must set it to zero. - * - __u8 - - ``data``\ [48] - - The packet payload. See :ref:`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. - - -Packets are always passed in ascending line number order, without -duplicate line numbers. The :ref:`write() <func-write>` function and -the :ref:`VIDIOC_QBUF` ioctl must return an ``EINVAL`` -error code when applications violate this rule. They must also return an -EINVAL error code when applications pass an incorrect field or line -number, or a combination of ``field``, ``line`` and ``id`` which has not -been negotiated with the :ref:`VIDIOC_G_FMT <VIDIOC_G_FMT>` or -:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl. When the line numbers are -unknown the driver must pass the packets in transmitted order. The -driver can insert empty packets with ``id`` set to zero anywhere in the -packet array. - -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. - -A sliced VBI device may support :ref:`read/write <rw>` and/or -streaming (:ref:`memory mapping <mmap>` and/or -:ref:`user pointer <userp>`) I/O. The latter bears the possibility of -synchronizing video and VBI data by using buffer timestamps. - - -Sliced VBI Data in MPEG Streams -=============================== - -If a device can produce an MPEG output stream, it may be capable of -providing -:ref:`negotiated sliced VBI services <sliced-vbi-format-negotitation>` -as data embedded in the MPEG stream. Users or applications control this -sliced VBI data insertion with the -:ref:`V4L2_CID_MPEG_STREAM_VBI_FMT <v4l2-mpeg-stream-vbi-fmt>` -control. - -If the driver does not provide the -:ref:`V4L2_CID_MPEG_STREAM_VBI_FMT <v4l2-mpeg-stream-vbi-fmt>` -control, or only allows that control to be set to -:ref:`V4L2_MPEG_STREAM_VBI_FMT_NONE <v4l2-mpeg-stream-vbi-fmt>`, -then the device cannot embed sliced VBI data in the MPEG stream. - -The -:ref:`V4L2_CID_MPEG_STREAM_VBI_FMT <v4l2-mpeg-stream-vbi-fmt>` -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. - -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. - -The following subsections specify the format of the embedded sliced VBI -data. - - -MPEG Stream Embedded, Sliced VBI Data Format: NONE --------------------------------------------------- - -The -:ref:`V4L2_MPEG_STREAM_VBI_FMT_NONE <v4l2-mpeg-stream-vbi-fmt>` -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. - - -MPEG Stream Embedded, Sliced VBI Data Format: IVTV --------------------------------------------------- - -The -:ref:`V4L2_MPEG_STREAM_VBI_FMT_IVTV <v4l2-mpeg-stream-vbi-fmt>` -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 *Private -Stream 1 PES* packet encapsulated in an MPEG-2 *Program Pack* in the -MPEG stream. - -*Historical context*: This format specification originates from a -custom, embedded, sliced VBI data format used by the ``ivtv`` driver. -This format has already been informally specified in the kernel sources -in the file ``Documentation/media/v4l-drivers/cx2341x.rst`` . 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. - -This format's use is *not* exclusive to the ``ivtv`` driver *nor* -exclusive to CX2341x devices, as the sliced VBI data packet insertion -into the MPEG stream is implemented in driver software. At least the -``cx18`` driver provides sliced VBI data insertion into an MPEG-2 PS in -this format as well. - -The following definitions specify the payload of the MPEG-2 *Private -Stream 1 PES* packets that contain sliced VBI data when -:ref:`V4L2_MPEG_STREAM_VBI_FMT_IVTV <v4l2-mpeg-stream-vbi-fmt>` -is set. (The MPEG-2 *Private Stream 1 PES* packet header and -encapsulating MPEG-2 *Program Pack* header are not detailed here. Please -refer to the MPEG-2 specifications for details on those packet headers.) - -The payload of the MPEG-2 *Private Stream 1 PES* packets that contain -sliced VBI data is specified by struct -:c:type:`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). - - -.. c:type:: v4l2_mpeg_vbi_fmt_ivtv - -struct v4l2_mpeg_vbi_fmt_ivtv ------------------------------ - -.. tabularcolumns:: |p{1.0cm}|p{3.8cm}|p{1.0cm}|p{11.2cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 1 2 - - * - __u8 - - ``magic``\ [4] - - - - A "magic" constant from :ref:`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, ``itv0`` or - ``ITV0``, to use for the payload data. - * - union - - (anonymous) - * - - - struct :c:type:`v4l2_mpeg_vbi_itv0` - - ``itv0`` - - 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. - * - - - struct :ref:`v4l2_mpeg_vbi_ITV0 <v4l2-mpeg-vbi-itv0-1>` - - ``ITV0`` - - 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. - - - -.. _v4l2-mpeg-vbi-fmt-ivtv-magic: - -Magic Constants for struct v4l2_mpeg_vbi_fmt_ivtv magic field -------------------------------------------------------------- - -.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}| - -.. flat-table:: - :header-rows: 1 - :stub-columns: 0 - :widths: 3 1 4 - - * - Defined Symbol - - Value - - Description - * - ``V4L2_MPEG_VBI_IVTV_MAGIC0`` - - "itv0" - - Indicates the ``itv0`` member of the union in struct - :c:type:`v4l2_mpeg_vbi_fmt_ivtv` is - valid. - * - ``V4L2_MPEG_VBI_IVTV_MAGIC1`` - - "ITV0" - - Indicates the ``ITV0`` member of the union in struct - :c:type:`v4l2_mpeg_vbi_fmt_ivtv` is - valid and that 36 lines of sliced VBI data are present. - - - -.. c:type:: v4l2_mpeg_vbi_itv0 - -.. c:type:: v4l2_mpeg_vbi_ITV0 - -structs v4l2_mpeg_vbi_itv0 and v4l2_mpeg_vbi_ITV0 -------------------------------------------------- - -.. tabularcolumns:: |p{5.2cm}|p{2.4cm}|p{9.9cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __le32 - - ``linemask``\ [2] - - Bitmasks indicating the VBI service lines present. These - ``linemask`` values are stored in little endian byte order in the - MPEG stream. Some reference ``linemask`` bit positions with their - corresponding VBI line number and video field are given below. - b\ :sub:`0` indicates the least significant bit of a ``linemask`` - value: - - - - :: - - linemask[0] b0: line 6 first field - linemask[0] b17: line 23 first field - linemask[0] b18: line 6 second field - linemask[0] b31: line 19 second field - linemask[1] b0: line 20 second field - linemask[1] b3: line 23 second field - linemask[1] b4-b31: unused and set to 0 - * - struct - :c:type:`v4l2_mpeg_vbi_itv0_line` - - ``line``\ [35] - - 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 ``linemask`` array, starting from b\ :sub:`0` - of ``linemask``\ [0] up through b\ :sub:`31` of ``linemask``\ [0], - and from b\ :sub:`0` of ``linemask``\ [1] up through b\ :sub:`3` of - ``linemask``\ [1]. ``line``\ [0] corresponds to the first bit - found set in the ``linemask`` array, ``line``\ [1] corresponds to - the second bit found set in the ``linemask`` array, etc. If no - ``linemask`` array bits are set, then ``line``\ [0] may contain - one line of unspecified data that should be ignored by - applications. - - - -.. _v4l2-mpeg-vbi-itv0-1: - -struct v4l2_mpeg_vbi_ITV0 -------------------------- - -.. tabularcolumns:: |p{5.2cm}|p{2.4cm}|p{9.9cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - struct - :c:type:`v4l2_mpeg_vbi_itv0_line` - - ``line``\ [36] - - A fixed length array of 36 lines of sliced VBI data. ``line``\ [0] - through ``line``\ [17] correspond to lines 6 through 23 of the - first field. ``line``\ [18] through ``line``\ [35] corresponds to - lines 6 through 23 of the second field. - - - -.. c:type:: v4l2_mpeg_vbi_itv0_line - -struct v4l2_mpeg_vbi_itv0_line ------------------------------- - -.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 1 2 - - * - __u8 - - ``id`` - - A line identifier value from - :ref:`ITV0-Line-Identifier-Constants` that indicates the type of - sliced VBI data stored on this line. - * - __u8 - - ``data``\ [42] - - The sliced VBI data for the line. - - - -.. _ITV0-Line-Identifier-Constants: - -Line Identifiers for struct v4l2_mpeg_vbi_itv0_line id field ------------------------------------------------------------- - -.. tabularcolumns:: |p{7.0cm}|p{1.8cm}|p{8.7cm}| - -.. flat-table:: - :header-rows: 1 - :stub-columns: 0 - :widths: 3 1 4 - - * - Defined Symbol - - Value - - Description - * - ``V4L2_MPEG_VBI_IVTV_TELETEXT_B`` - - 1 - - Refer to :ref:`Sliced VBI services <vbi-services2>` for a - description of the line payload. - * - ``V4L2_MPEG_VBI_IVTV_CAPTION_525`` - - 4 - - Refer to :ref:`Sliced VBI services <vbi-services2>` for a - description of the line payload. - * - ``V4L2_MPEG_VBI_IVTV_WSS_625`` - - 5 - - Refer to :ref:`Sliced VBI services <vbi-services2>` for a - description of the line payload. - * - ``V4L2_MPEG_VBI_IVTV_VPS`` - - 7 - - Refer to :ref:`Sliced VBI services <vbi-services2>` for a - description of the line payload. - - - -.. [#f1] - According to :ref:`ETS 300 706 <ets300706>` lines 6-22 of the first - field and lines 5-22 of the second field may carry Teletext data. - -.. [#f2] - See also :ref:`vbi-525` and :ref:`vbi-625`. |