Avoid adding an extra columns when describing unions in the documentation.
That makes it much harder to read. See e.g. VIDIOC_QUERY_EXT_CTRLS.
Instead start off a union with 'union {' and end it with an extra row
containing '}'.
This leaves a lot more space for the description of the fields.
This formatting technique was used in a few places already, but this
patches fixes all remaining occurrences of 'union' in the media uAPI.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: Nicolas Dufresne <nicolas@ndufresne.ca>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
.. flat-table:: struct cec_connector_info
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 8
+ :widths: 1 1 8
* - __u32
- ``type``
- The type of connector this adapter is associated with.
- * - union
+ * - union {
- ``(anonymous)``
- -
- * -
- - ``struct cec_drm_connector_info``
+ * - ``struct cec_drm_connector_info``
- drm
- :ref:`cec-drm-connector-info`
+ * - }
+ -
.. tabularcolumns:: |p{4.4cm}|p{2.5cm}|p{10.6cm}|
.. flat-table:: struct cec_event
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 8
+ :widths: 1 1 8
* - __u64
- ``ts``
- - :cspan:`1`\ Timestamp of the event in ns.
+ - Timestamp of the event in ns.
The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock.
To access the same clock from userspace use :c:func:`clock_gettime`.
* - __u32
- ``event``
- - :cspan:`1` The CEC event type, see :ref:`cec-events`.
+ - The CEC event type, see :ref:`cec-events`.
* - __u32
- ``flags``
- - :cspan:`1` Event flags, see :ref:`cec-event-flags`.
- * - union
+ - Event flags, see :ref:`cec-event-flags`.
+ * - union {
- (anonymous)
- -
- -
- * -
- - struct cec_event_state_change
+ * - struct cec_event_state_change
- ``state_change``
- The new adapter state as sent by the :ref:`CEC_EVENT_STATE_CHANGE <CEC-EVENT-STATE-CHANGE>`
event.
- * -
- - struct cec_event_lost_msgs
+ * - struct cec_event_lost_msgs
- ``lost_msgs``
- The number of lost messages as sent by the :ref:`CEC_EVENT_LOST_MSGS <CEC-EVENT-LOST-MSGS>`
event.
+ * - }
+ -
.. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{11.0cm}|
.. flat-table:: struct media_entity_desc
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 1 8
+ :widths: 2 2 1 8
* - __u32
- ``id``
-
- -
- Entity ID, set by the application. When the ID is or'ed with
``MEDIA_ENT_ID_FLAG_NEXT``, the driver clears the flag and returns
the first entity with a larger ID. Do not expect that the ID will
* - char
- ``name``\ [32]
-
- -
- Entity name as an UTF-8 NULL-terminated string. This name must be unique
within the media topology.
* - __u32
- ``type``
-
- -
- Entity type, see :ref:`media-entity-functions` for details.
* - __u32
- ``revision``
-
- -
- Entity revision. Always zero (obsolete)
* - __u32
- ``flags``
-
- -
- Entity flags, see :ref:`media-entity-flag` for details.
* - __u32
- ``group_id``
-
- -
- Entity group ID. Always zero (obsolete)
* - __u16
- ``pads``
-
- -
- Number of pads
* - __u16
- ``links``
-
- -
- Total number of outbound links. Inbound links are not counted in
this field.
* - __u32
- ``reserved[4]``
-
- -
- Reserved for future extensions. Drivers and applications must set
the array to zero.
- * - union
+ * - union {
+ - (anonymous)
- * -
- - struct
+ * - struct
- ``dev``
-
- Valid for (sub-)devices that create a single device node.
* -
- -
- __u32
- ``major``
- Device node major number.
* -
- -
- __u32
- ``minor``
- Device node minor number.
- * -
- - __u8
+ * - __u8
- ``raw``\ [184]
-
-
+ * - }
+ -
Return Value
.. flat-table:: struct v4l2_buffer
:header-rows: 0
:stub-columns: 0
- :widths: 1 2 1 10
+ :widths: 1 2 10
* - __u32
- ``index``
- -
- Number of the buffer, set by the application except when calling
:ref:`VIDIOC_DQBUF <VIDIOC_QBUF>`, then it is set by the
driver. This field can range from zero to the number of buffers
:ref:`VIDIOC_CREATE_BUFS` minus one.
* - __u32
- ``type``
- -
- Type of the buffer, same as struct
:c:type:`v4l2_format` ``type`` or struct
:c:type:`v4l2_requestbuffers` ``type``, set
by the application. See :c:type:`v4l2_buf_type`
* - __u32
- ``bytesused``
- -
- The number of bytes occupied by the data in the buffer. It depends
on the negotiated data format and may change with each buffer for
compressed variable size data like JPEG images. Drivers must set
``planes`` pointer is used instead.
* - __u32
- ``flags``
- -
- Flags set by the application or driver, see :ref:`buffer-flags`.
* - __u32
- ``field``
- -
- Indicates the field order of the image in the buffer, see
:c:type:`v4l2_field`. This field is not used when the buffer
contains VBI data. Drivers must set it when ``type`` refers to a
capture stream, applications when it refers to an output stream.
* - struct timeval
- ``timestamp``
- -
- For capture streams this is time when the first data byte was
captured, as returned by the :c:func:`clock_gettime()` function
for the relevant clock id; see ``V4L2_BUF_FLAG_TIMESTAMP_*`` in
stream.
* - struct :c:type:`v4l2_timecode`
- ``timecode``
- -
- When the ``V4L2_BUF_FLAG_TIMECODE`` flag is set in ``flags``, this
structure contains a frame timecode. In
:c:type:`V4L2_FIELD_ALTERNATE <v4l2_field>` mode the top and
independent of the ``timestamp`` and ``sequence`` fields.
* - __u32
- ``sequence``
- -
- Set by the driver, counting the frames (not fields!) in sequence.
This field is set for both input and output devices.
- * - :cspan:`3`
+ * - :cspan:`2`
In :c:type:`V4L2_FIELD_ALTERNATE <v4l2_field>` mode the top and
bottom field have the same sequence number. The count starts at
* - __u32
- ``memory``
- -
- This field must be set by applications and/or drivers in
accordance with the selected I/O method. See :c:type:`v4l2_memory`
- * - union
+ * - union {
- ``m``
- * -
- - __u32
+ * - __u32
- ``offset``
- For the single-planar API and when ``memory`` is
``V4L2_MEMORY_MMAP`` this is the offset of the buffer from the
and apart of serving as parameter to the
:ref:`mmap() <func-mmap>` function not useful for applications.
See :ref:`mmap` for details
- * -
- - unsigned long
+ * - unsigned long
- ``userptr``
- For the single-planar API and when ``memory`` is
``V4L2_MEMORY_USERPTR`` this is a pointer to the buffer (casted to
unsigned long type) in virtual memory, set by the application. See
:ref:`userp` for details.
- * -
- - struct v4l2_plane
+ * - struct v4l2_plane
- ``*planes``
- When using the multi-planar API, contains a userspace pointer to
an array of struct :c:type:`v4l2_plane`. The size of
the array should be put in the ``length`` field of this
struct :c:type:`v4l2_buffer` structure.
- * -
- - int
+ * - int
- ``fd``
- For the single-plane API and when ``memory`` is
``V4L2_MEMORY_DMABUF`` this is the file descriptor associated with
a DMABUF buffer.
+ * - }
+ -
* - __u32
- ``length``
- -
- Size of the buffer (not the payload) in bytes for the
single-planar API. This is set by the driver based on the calls to
:ref:`VIDIOC_REQBUFS` and/or
actual number of valid elements in that array.
* - __u32
- ``reserved2``
- -
- A place holder for future extensions. Drivers and applications
must set this to 0.
* - __u32
- ``request_fd``
- -
- The file descriptor of the request to queue the buffer to. If the flag
``V4L2_BUF_FLAG_REQUEST_FD`` is set, then the buffer will be
queued to this request. If the flag is not set, then this field will
.. flat-table::
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 1 1 2
* - __u32
- ``bytesused``
- -
- The number of bytes occupied by data in the plane (its payload).
Drivers must set this field when ``type`` refers to a capture
stream, applications when it refers to an output stream. If the
which may not be 0.
* - __u32
- ``length``
- -
- Size in bytes of the plane (not its payload). This is set by the
driver based on the calls to
:ref:`VIDIOC_REQBUFS` and/or
:ref:`VIDIOC_CREATE_BUFS`.
- * - union
+ * - union {
- ``m``
- -
- -
- * -
- - __u32
+ * - __u32
- ``mem_offset``
- When the memory type in the containing struct
:c:type:`v4l2_buffer` is ``V4L2_MEMORY_MMAP``, this
is the value that should be passed to :ref:`mmap() <func-mmap>`,
similar to the ``offset`` field in struct
:c:type:`v4l2_buffer`.
- * -
- - unsigned long
+ * - unsigned long
- ``userptr``
- When the memory type in the containing struct
:c:type:`v4l2_buffer` is ``V4L2_MEMORY_USERPTR``,
this is a userspace pointer to the memory allocated for this plane
by an application.
- * -
- - int
+ * - int
- ``fd``
- When the memory type in the containing struct
:c:type:`v4l2_buffer` is ``V4L2_MEMORY_DMABUF``,
this is a file descriptor associated with a DMABUF buffer, similar
to the ``fd`` field in struct :c:type:`v4l2_buffer`.
+ * - }
+ -
* - __u32
- ``data_offset``
- -
- Offset in bytes to video data in the plane. Drivers must set this
field when ``type`` refers to a capture stream, applications when
it refers to an output stream.
at offset ``data_offset`` from the start of the plane.
* - __u32
- ``reserved[11]``
- -
- Reserved for future use. Should be zeroed by drivers and
applications.
.. flat-table::
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 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
+ * - union {
- (anonymous)
- * -
- - struct :c:type:`v4l2_mpeg_vbi_itv0`
+ * - 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>`
+ * - 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:
* - __u8
- ``flags``
- Flags set by the application or driver, see :ref:`format-flags`.
- * - :cspan:`2` union { (anonymous)
+ * - union {
+ - (anonymous)
* - __u8
- ``ycbcr_enc``
- Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
This information supplements the ``colorspace`` and must be set by
the driver for capture streams and by the application for output
streams, see :ref:`colorspaces`.
- * - :cspan:`2` }
+ * - }
+ -
* - __u8
- ``quantization``
- Quantization range, from enum :c:type:`v4l2_quantization`.
- Flags set by the application or driver, see :ref:`format-flags`.
* - union {
- (anonymous)
- -
* - __u32
- ``ycbcr_enc``
- Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`.
streams, see :ref:`colorspaces`.
* - }
-
- -
* - __u32
- ``quantization``
- Quantization range, from enum :c:type:`v4l2_quantization`.
.. flat-table:: struct v4l2_dbg_match
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 1 1 2
* - __u32
- ``type``
- See :ref:`name-chip-match-types` for a list of possible types.
- * - union
+ * - union {
- (anonymous)
- * -
- - __u32
+ * - __u32
- ``addr``
- Match a chip by this number, interpreted according to the ``type``
field.
- * -
- - char
+ * - char
- ``name[32]``
- Match a chip by this name, interpreted according to the ``type``
field. Currently unused.
+ * - }
+ -
.. flat-table:: struct v4l2_dbg_match
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 1 1 2
* - __u32
- ``type``
- See :ref:`chip-match-types` for a list of possible types.
- * - union
+ * - union {
- (anonymous)
- * -
- - __u32
+ * - __u32
- ``addr``
- Match a chip by this number, interpreted according to the ``type``
field.
- * -
- - char
+ * - char
- ``name[32]``
- Match a chip by this name, interpreted according to the ``type``
field. Currently unused.
+ * - }
+ -
.. flat-table:: struct v4l2_decoder_cmd
:header-rows: 0
:stub-columns: 0
- :widths: 11 24 12 16 106
+ :widths: 1 1 1 3
* - __u32
- ``cmd``
-
- -
- The decoder command, see :ref:`decoder-cmds`.
* - __u32
- ``flags``
-
- -
- Flags to go with the command. If no flags are defined for this
command, drivers and applications must set this field to zero.
- * - union
+ * - union {
- (anonymous)
- -
- -
- -
- * -
- - struct
+ * - struct
- ``start``
-
- Structure containing additional data for the
``V4L2_DEC_CMD_START`` command.
* -
- -
- __s32
- ``speed``
- Playback speed and direction. The playback speed is defined as
of 1 steps just one frame forward, a speed of -1 steps just one
frame back.
* -
- -
- __u32
- ``format``
- Format restrictions. This field is set by the driver, not the
GOPs, which it can then play in reverse order. So to implement
reverse playback the application must feed the decoder the last
GOP in the video file, then the GOP before that, etc. etc.
- * -
- - struct
+ * - struct
- ``stop``
-
- Structure containing additional data for the ``V4L2_DEC_CMD_STOP``
command.
* -
- -
- __u64
- ``pts``
- Stop playback at this ``pts`` or immediately if the playback is
already past that timestamp. Leave to 0 if you want to stop after
the last frame was decoded.
- * -
- - struct
+ * - struct
- ``raw``
- -
- -
* -
- -
- __u32
- ``data``\ [16]
- Reserved for future extensions. Drivers and applications must set
the array to zero.
+ * - }
+ -
.. flat-table:: struct v4l2_event
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
* - __u32
- ``type``
- -
- Type of the event, see :ref:`event-type`.
- * - union
+ * - union {
- ``u``
- -
- -
- * -
- - struct :c:type:`v4l2_event_vsync`
+ * - struct :c:type:`v4l2_event_vsync`
- ``vsync``
- Event data for event ``V4L2_EVENT_VSYNC``.
- * -
- - struct :c:type:`v4l2_event_ctrl`
+ * - struct :c:type:`v4l2_event_ctrl`
- ``ctrl``
- Event data for event ``V4L2_EVENT_CTRL``.
- * -
- - struct :c:type:`v4l2_event_frame_sync`
+ * - struct :c:type:`v4l2_event_frame_sync`
- ``frame_sync``
- Event data for event ``V4L2_EVENT_FRAME_SYNC``.
- * -
- - struct :c:type:`v4l2_event_motion_det`
+ * - struct :c:type:`v4l2_event_motion_det`
- ``motion_det``
- Event data for event V4L2_EVENT_MOTION_DET.
- * -
- - struct :c:type:`v4l2_event_src_change`
+ * - struct :c:type:`v4l2_event_src_change`
- ``src_change``
- Event data for event V4L2_EVENT_SOURCE_CHANGE.
- * -
- - __u8
+ * - __u8
- ``data``\ [64]
- Event data. Defined by the event type. The union should be used to
define easily accessible type for events.
+ * - }
+ -
* - __u32
- ``pending``
- -
- Number of pending events excluding this one.
* - __u32
- ``sequence``
- -
- Event sequence number. The sequence number is incremented for
every subscribed event that takes place. If sequence numbers are
not contiguous it means that events have been lost.
* - struct timespec
- ``timestamp``
- -
- Event timestamp. The timestamp has been taken from the
``CLOCK_MONOTONIC`` clock. To access the same clock outside V4L2,
use :c:func:`clock_gettime`.
* - u32
- ``id``
- -
- The ID associated with the event source. If the event does not
have an associated ID (this depends on the event type), then this
is 0.
* - __u32
- ``reserved``\ [8]
- -
- Reserved for future extensions. Drivers must set the array to
zero.
.. flat-table:: struct v4l2_event_ctrl
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
* - __u32
- ``changes``
- -
- A bitmask that tells what has changed. See
:ref:`ctrl-changes-flags`.
* - __u32
- ``type``
- -
- The type of the control. See enum
:c:type:`v4l2_ctrl_type`.
- * - union (anonymous)
- -
- -
- -
- * -
- - __s32
+ * - union {
+ - (anonymous)
+ * - __s32
- ``value``
- The 32-bit value of the control for 32-bit control types. This is
0 for string controls since the value of a string cannot be passed
using :ref:`VIDIOC_DQEVENT`.
- * -
- - __s64
+ * - __s64
- ``value64``
- The 64-bit value of the control for 64-bit control types.
+ * - }
+ -
* - __u32
- ``flags``
- -
- The control flags. See :ref:`control-flags`.
* - __s32
- ``minimum``
- -
- The minimum value of the control. See struct
:ref:`v4l2_queryctrl <v4l2-queryctrl>`.
* - __s32
- ``maximum``
- -
- The maximum value of the control. See struct
:ref:`v4l2_queryctrl <v4l2-queryctrl>`.
* - __s32
- ``step``
- -
- The step value of the control. See struct
:ref:`v4l2_queryctrl <v4l2-queryctrl>`.
* - __s32
- ``default_value``
- -
- The default value value of the control. See struct
:ref:`v4l2_queryctrl <v4l2-queryctrl>`.
.. flat-table:: struct v4l2_dv_timings_cap
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
* - __u32
- ``type``
- Reserved for future extensions.
Drivers and applications must set the array to zero.
- * - union
- -
- -
- * -
- - struct :c:type:`v4l2_bt_timings_cap`
+ * - union {
+ - (anonymous)
+ * - struct :c:type:`v4l2_bt_timings_cap`
- ``bt``
- BT.656/1120 timings capabilities of the hardware.
- * -
- - __u32
+ * - __u32
- ``raw_data``\ [32]
+ * - }
-
.. tabularcolumns:: |p{7.0cm}|p{10.5cm}|
* - __u32
- ``index``
- -
- IN: Index of the given frame interval in the enumeration.
* - __u32
- ``pixel_format``
- -
- IN: Pixel format for which the frame intervals are enumerated.
* - __u32
- ``width``
- -
- IN: Frame width for which the frame intervals are enumerated.
* - __u32
- ``height``
- -
- IN: Frame height for which the frame intervals are enumerated.
* - __u32
- ``type``
- -
- OUT: Frame interval type the device supports.
- * - union
- -
- -
+ * - union {
+ - (anonymous)
- OUT: Frame interval with the given index.
- * -
- - struct :c:type:`v4l2_fract`
+ * - struct :c:type:`v4l2_fract`
- ``discrete``
- Frame interval [s].
- * -
- - struct :c:type:`v4l2_frmival_stepwise`
+ * - struct :c:type:`v4l2_frmival_stepwise`
- ``stepwise``
-
+ * - }
+ -
+ -
* - __u32
- ``reserved[2]``
-
* - __u32
- ``index``
- -
- IN: Index of the given frame size in the enumeration.
* - __u32
- ``pixel_format``
- -
- IN: Pixel format for which the frame sizes are enumerated.
* - __u32
- ``type``
- -
- OUT: Frame size type the device supports.
- * - union
- -
- -
+ * - union {
+ - (anonymous)
- OUT: Frame size with the given index.
- * -
- - struct :c:type:`v4l2_frmsize_discrete`
+ * - struct :c:type:`v4l2_frmsize_discrete`
- ``discrete``
-
- * -
- - struct :c:type:`v4l2_frmsize_stepwise`
+ * - struct :c:type:`v4l2_frmsize_stepwise`
- ``stepwise``
-
+ * - }
+ -
+ -
* - __u32
- ``reserved[2]``
- -
- Reserved space for future use. Must be zeroed by drivers and
applications.
.. flat-table:: struct v4l2_dv_timings
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
* - __u32
- ``type``
- -
- Type of DV timings as listed in :ref:`dv-timing-types`.
- * - union
- -
- -
- * -
- - struct :c:type:`v4l2_bt_timings`
+ * - union {
+ - (anonymous)
+ * - struct :c:type:`v4l2_bt_timings`
- ``bt``
- Timings defined by BT.656/1120 specifications
- * -
- - __u32
+ * - __u32
- ``reserved``\ [32]
-
+ * - }
+ -
.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
.. flat-table:: struct v4l2_ext_control
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 1 1 2
* - __u32
- ``id``
- -
- Identifies the control, set by the application.
* - __u32
- ``size``
- -
- The total size in bytes of the payload of this control. This is
normally 0, but for pointer controls this should be set to the
size of the memory containing the payload, or that will receive
*length* of the string may well be much smaller.
* - __u32
- ``reserved2``\ [1]
- -
- Reserved for future extensions. Drivers and applications must set
the array to zero.
- * - union
+ * - union {
- (anonymous)
- * -
- - __s32
+ * - __s32
- ``value``
- New value or current value. Valid if this control is not of type
``V4L2_CTRL_TYPE_INTEGER64`` and ``V4L2_CTRL_FLAG_HAS_PAYLOAD`` is
not set.
- * -
- - __s64
+ * - __s64
- ``value64``
- New value or current value. Valid if this control is of type
``V4L2_CTRL_TYPE_INTEGER64`` and ``V4L2_CTRL_FLAG_HAS_PAYLOAD`` is
not set.
- * -
- - char *
+ * - char *
- ``string``
- A pointer to a string. Valid if this control is of type
``V4L2_CTRL_TYPE_STRING``.
- * -
- - __u8 *
+ * - __u8 *
- ``p_u8``
- A pointer to a matrix control of unsigned 8-bit values. Valid if
this control is of type ``V4L2_CTRL_TYPE_U8``.
- * -
- - __u16 *
+ * - __u16 *
- ``p_u16``
- A pointer to a matrix control of unsigned 16-bit values. Valid if
this control is of type ``V4L2_CTRL_TYPE_U16``.
- * -
- - __u32 *
+ * - __u32 *
- ``p_u32``
- A pointer to a matrix control of unsigned 32-bit values. Valid if
this control is of type ``V4L2_CTRL_TYPE_U32``.
- * -
- - :c:type:`v4l2_area` *
+ * - :c:type:`v4l2_area` *
- ``p_area``
- A pointer to a struct :c:type:`v4l2_area`. Valid if this control is
of type ``V4L2_CTRL_TYPE_AREA``.
- * -
- - void *
+ * - void *
- ``ptr``
- A pointer to a compound type which can be an N-dimensional array
and/or a compound type (the control's type is >=
``V4L2_CTRL_COMPOUND_TYPES``). Valid if
``V4L2_CTRL_FLAG_HAS_PAYLOAD`` is set for this control.
+ * - }
+ -
.. tabularcolumns:: |p{4.0cm}|p{2.2cm}|p{2.1cm}|p{8.2cm}|
.. flat-table:: struct v4l2_ext_controls
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
- * - union
+ * - union {
- (anonymous)
- * -
- - __u32
+ * - __u32
- ``ctrl_class``
- The control class to which all controls belong, see
:ref:`ctrl-class`. Drivers that use a kernel framework for
support this can be tested by setting ``ctrl_class`` to 0 and
calling :ref:`VIDIOC_TRY_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>` with a ``count`` of 0. If that
succeeds, then the driver supports this feature.
- * -
- - __u32
+ * - __u32
- ``which``
- Which value of the control to get/set/try.
``V4L2_CTRL_WHICH_CUR_VAL`` will return the current value of the
by setting ctrl_class to ``V4L2_CTRL_WHICH_CUR_VAL`` and calling
VIDIOC_TRY_EXT_CTRLS with a count of 0. If that fails, then the
driver does not support ``V4L2_CTRL_WHICH_CUR_VAL``.
+ * - }
+ -
* - __u32
- ``count``
- The number of controls in the controls array. May also be zero.
* - __u32
- ``type``
- -
- Type of the data stream, see :c:type:`v4l2_buf_type`.
- * - union
+ * - union {
- ``fmt``
- * -
- - struct :c:type:`v4l2_pix_format`
+ * - struct :c:type:`v4l2_pix_format`
- ``pix``
- Definition of an image format, see :ref:`pixfmt`, used by video
capture and output devices.
- * -
- - struct :c:type:`v4l2_pix_format_mplane`
+ * - struct :c:type:`v4l2_pix_format_mplane`
- ``pix_mp``
- Definition of an image format, see :ref:`pixfmt`, used by video
capture and output devices that support the
:ref:`multi-planar version of the API <planar-apis>`.
- * -
- - struct :c:type:`v4l2_window`
+ * - struct :c:type:`v4l2_window`
- ``win``
- Definition of an overlaid image, see :ref:`overlay`, used by
video overlay devices.
- * -
- - struct :c:type:`v4l2_vbi_format`
+ * - struct :c:type:`v4l2_vbi_format`
- ``vbi``
- Raw VBI capture or output parameters. This is discussed in more
detail in :ref:`raw-vbi`. Used by raw VBI capture and output
devices.
- * -
- - struct :c:type:`v4l2_sliced_vbi_format`
+ * - struct :c:type:`v4l2_sliced_vbi_format`
- ``sliced``
- Sliced VBI capture or output parameters. See :ref:`sliced` for
details. Used by sliced VBI capture and output devices.
- * -
- - struct :c:type:`v4l2_sdr_format`
+ * - struct :c:type:`v4l2_sdr_format`
- ``sdr``
- Definition of a data format, see :ref:`pixfmt`, used by SDR
capture and output devices.
- * -
- - struct :c:type:`v4l2_meta_format`
+ * - struct :c:type:`v4l2_meta_format`
- ``meta``
- Definition of a metadata format, see :ref:`meta-formats`, used by
metadata capture devices.
- * -
- - __u8
+ * - __u8
- ``raw_data``\ [200]
- Place holder for future extensions.
+ * - }
+ -
Return Value
.. flat-table:: struct v4l2_streamparm
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 1 2
+ :widths: 1 1 2
* - __u32
- ``type``
- -
- The buffer (stream) type, same as struct
:c:type:`v4l2_format` ``type``, set by the
application. See :c:type:`v4l2_buf_type`.
- * - union
+ * - union {
- ``parm``
- -
- -
- * -
- - struct :c:type:`v4l2_captureparm`
+ * - struct :c:type:`v4l2_captureparm`
- ``capture``
- Parameters for capture devices, used when ``type`` is
``V4L2_BUF_TYPE_VIDEO_CAPTURE`` or
``V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE``.
- * -
- - struct :c:type:`v4l2_outputparm`
+ * - struct :c:type:`v4l2_outputparm`
- ``output``
- Parameters for output devices, used when ``type`` is
``V4L2_BUF_TYPE_VIDEO_OUTPUT`` or ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``.
- * -
- - __u8
+ * - __u8
- ``raw_data``\ [200]
- A place holder for future extensions.
+ * - }
+ -
.. flat-table:: struct v4l2_querymenu
:header-rows: 0
:stub-columns: 0
- :widths: 1 1 2 1
+ :widths: 1 1 2
* - __u32
- -
- ``id``
- Identifies the control, set by the application from the respective
struct :ref:`v4l2_queryctrl <v4l2-queryctrl>` ``id``.
* - __u32
- -
- ``index``
- Index of the menu item, starting at zero, set by the application.
- * - union
- -
- -
- -
- * -
- - __u8
+ * - union {
+ - (anonymous)
+ * - __u8
- ``name``\ [32]
- Name of the menu item, a NUL-terminated ASCII string. This
information is intended for the user. This field is valid for
``V4L2_CTRL_TYPE_MENU`` type controls.
- * -
- - __s64
+ * - __s64
- ``value``
- Value of the integer menu item. This field is valid for
``V4L2_CTRL_TYPE_INTEGER_MENU`` type controls.
- * - __u32
+ * - }
-
+ * - __u32
- ``reserved``
- Reserved for future extensions. Drivers must set the array to
zero.