8968da9b86
This patch touches on places where it shouldn't: image files and code examples. Also, it doesn't fix all array occurrences. So, let's revert it. This reverts commit ffbab694ede33c294e5864a5e0bf4d1474446a71.
277 lines
5.1 KiB
ReStructuredText
277 lines
5.1 KiB
ReStructuredText
.. -*- coding: utf-8; mode: rst -*-
|
|
|
|
.. _VIDIOC_G_SLICED_VBI_CAP:
|
|
|
|
*****************************
|
|
ioctl VIDIOC_G_SLICED_VBI_CAP
|
|
*****************************
|
|
|
|
Name
|
|
====
|
|
|
|
VIDIOC_G_SLICED_VBI_CAP - Query sliced VBI capabilities
|
|
|
|
|
|
Synopsis
|
|
========
|
|
|
|
.. cpp:function:: int ioctl( int fd, int request, struct v4l2_sliced_vbi_cap *argp )
|
|
|
|
|
|
Arguments
|
|
=========
|
|
|
|
``fd``
|
|
File descriptor returned by :ref:`open() <func-open>`.
|
|
|
|
``request``
|
|
VIDIOC_G_SLICED_VBI_CAP
|
|
|
|
``argp``
|
|
|
|
|
|
Description
|
|
===========
|
|
|
|
To find out which data services are supported by a sliced VBI capture or
|
|
output device, applications initialize the ``type`` field of a struct
|
|
:ref:`v4l2_sliced_vbi_cap <v4l2-sliced-vbi-cap>`, clear the
|
|
``reserved`` array and call the :ref:`VIDIOC_G_SLICED_VBI_CAP <VIDIOC_G_SLICED_VBI_CAP>` ioctl. The
|
|
driver fills in the remaining fields or returns an ``EINVAL`` error code if
|
|
the sliced VBI API is unsupported or ``type`` is invalid.
|
|
|
|
.. note:: The ``type`` field was added, and the ioctl changed from read-only
|
|
to write-read, in Linux 2.6.19.
|
|
|
|
|
|
.. _v4l2-sliced-vbi-cap:
|
|
|
|
.. flat-table:: struct v4l2_sliced_vbi_cap
|
|
:header-rows: 0
|
|
:stub-columns: 0
|
|
:widths: 3 3 2 2 2
|
|
|
|
|
|
- .. row 1
|
|
|
|
- __u16
|
|
|
|
- ``service_set``
|
|
|
|
- :cspan:`2` A set of all data services supported by the driver.
|
|
Equal to the union of all elements of the ``service_lines`` array.
|
|
|
|
- .. row 2
|
|
|
|
- __u16
|
|
|
|
- ``service_lines``\ [2][24]
|
|
|
|
- :cspan:`2` Each element of this array contains a set of data
|
|
services the hardware can look for or insert into a particular
|
|
scan line. Data services are defined in :ref:`vbi-services`.
|
|
Array indices map to ITU-R line numbers (see also :ref:`vbi-525`
|
|
and :ref:`vbi-625`) as follows:
|
|
|
|
- .. row 3
|
|
|
|
-
|
|
-
|
|
- Element
|
|
|
|
- 525 line systems
|
|
|
|
- 625 line systems
|
|
|
|
- .. row 4
|
|
|
|
-
|
|
-
|
|
- ``service_lines``\ [0][1]
|
|
|
|
- 1
|
|
|
|
- 1
|
|
|
|
- .. row 5
|
|
|
|
-
|
|
-
|
|
- ``service_lines``\ [0][23]
|
|
|
|
- 23
|
|
|
|
- 23
|
|
|
|
- .. row 6
|
|
|
|
-
|
|
-
|
|
- ``service_lines``\ [1][1]
|
|
|
|
- 264
|
|
|
|
- 314
|
|
|
|
- .. row 7
|
|
|
|
-
|
|
-
|
|
- ``service_lines``\ [1][23]
|
|
|
|
- 286
|
|
|
|
- 336
|
|
|
|
- .. row 8
|
|
|
|
-
|
|
|
|
- .. row 9
|
|
|
|
-
|
|
-
|
|
- :cspan:`2` 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 may be 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. Applications can learn about these limits using the
|
|
:ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl as described in
|
|
:ref:`sliced`.
|
|
|
|
- .. row 10
|
|
|
|
-
|
|
|
|
- .. row 11
|
|
|
|
-
|
|
-
|
|
- :cspan:`2` Drivers must set ``service_lines`` [0][0] and
|
|
``service_lines``\ [1][0] to zero.
|
|
|
|
- .. row 12
|
|
|
|
- __u32
|
|
|
|
- ``type``
|
|
|
|
- Type of the data stream, see :ref:`v4l2-buf-type`. Should be
|
|
``V4L2_BUF_TYPE_SLICED_VBI_CAPTURE`` or
|
|
``V4L2_BUF_TYPE_SLICED_VBI_OUTPUT``.
|
|
|
|
- .. row 13
|
|
|
|
- __u32
|
|
|
|
- ``reserved``\ [3]
|
|
|
|
- :cspan:`2` This array is reserved for future extensions.
|
|
Applications and drivers must set it to zero.
|
|
|
|
|
|
|
|
.. _vbi-services:
|
|
|
|
.. flat-table:: Sliced VBI services
|
|
:header-rows: 1
|
|
:stub-columns: 0
|
|
:widths: 2 1 1 2 2
|
|
|
|
|
|
- .. row 1
|
|
|
|
- Symbol
|
|
|
|
- Value
|
|
|
|
- Reference
|
|
|
|
- Lines, usually
|
|
|
|
- Payload
|
|
|
|
- .. row 2
|
|
|
|
- ``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.
|
|
|
|
- .. row 3
|
|
|
|
- ``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.
|
|
|
|
- .. row 4
|
|
|
|
- ``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.
|
|
|
|
- .. row 5
|
|
|
|
- ``V4L2_SLICED_WSS_625``
|
|
|
|
- 0x4000
|
|
|
|
- :ref:`en300294`, :ref:`itu1119`
|
|
|
|
- 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
|
|
|
|
- .. row 6
|
|
|
|
- ``V4L2_SLICED_VBI_525``
|
|
|
|
- 0x1000
|
|
|
|
- :cspan:`2` Set of services applicable to 525 line systems.
|
|
|
|
- .. row 7
|
|
|
|
- ``V4L2_SLICED_VBI_625``
|
|
|
|
- 0x4401
|
|
|
|
- :cspan:`2` Set of services applicable to 625 line systems.
|
|
|
|
|
|
Return Value
|
|
============
|
|
|
|
On success 0 is returned, on error -1 and the ``errno`` variable is set
|
|
appropriately. The generic error codes are described at the
|
|
:ref:`Generic Error Codes <gen-errors>` chapter.
|
|
|
|
EINVAL
|
|
The value in the ``type`` field is wrong.
|