* - __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 {
  - ``parm``
* - 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`
  - ``output``
  - Parameters for output devices, used when ``type`` is
``V4L2_BUF_TYPE_VIDEO_OUTPUT`` or ``V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE``.
* - __u8
  - ``raw_data``\ [200]
  - A place holder for future extensions.
* - }

* - __u32
  - ``capability``
  - See :ref:`parm-caps`.
* - __u32
  - ``capturemode``
  - Set by drivers and applications, see :ref:`parm-flags`.
* - struct :c:type:`v4l2_fract`
  - ``timeperframe``
  - This is the desired period between successive frames captured by
the driver, in seconds.
* - :cspan:`2`

This will configure the speed at which the video source (e.g. a sensor)
generates video frames. If the speed is fixed, then the driver may
choose to skip or repeat frames in order to achieve the requested
frame rate.

For stateful encoders (see :ref:`encoder`) this represents the
frame interval that is typically embedded in the encoded video stream.

Applications store here the desired frame period, drivers return
the actual frame period.

Changing the video standard (also implicitly by switching
the video input) may reset this parameter to the nominal frame
period. To reset manually applications can just set this field to
zero.

Drivers support this function only when they set the
``V4L2_CAP_TIMEPERFRAME`` flag in the ``capability`` field.
* - __u32
  - ``extendedmode``
  - Custom (driver specific) streaming parameters. When unused,
applications and drivers must set this field to zero. Applications
using this field should check the driver name and version, see
:ref:`querycap`.
* - __u32
  - ``readbuffers``
  - Applications set this field to the desired number of buffers used
internally by the driver in :c:func:`read()` mode.
Drivers return the actual number of buffers. When an application
requests zero buffers, drivers should just return the current
setting rather than the minimum or an error code. For details see
:ref:`rw`.
* - __u32
  - ``reserved``\ [4]
  - Reserved for future extensions. Drivers and applications must set
the array to zero.

* - __u32
  - ``capability``
  - See :ref:`parm-caps`.
* - __u32
  - ``outputmode``
  - Set by drivers and applications, see :ref:`parm-flags`.
* - struct :c:type:`v4l2_fract`
  - ``timeperframe``
  - This is the desired period between successive frames output by the
driver, in seconds.
* - :cspan:`2`

The field is intended to repeat frames on the driver side in
:c:func:`write()` mode (in streaming mode timestamps
can be used to throttle the output), saving I/O bandwidth.

For stateful encoders (see :ref:`encoder`) this represents the
frame interval that is typically embedded in the encoded video stream
and it provides a hint to the encoder of the speed at which raw
frames are queued up to the encoder.

Applications store here the desired frame period, drivers return
the actual frame period.

Changing the video standard (also implicitly by switching
the video output) may reset this parameter to the nominal frame
period. To reset manually applications can just set this field to
zero.

Drivers support this function only when they set the
``V4L2_CAP_TIMEPERFRAME`` flag in the ``capability`` field.
* - __u32
  - ``extendedmode``
  - Custom (driver specific) streaming parameters. When unused,
applications and drivers must set this field to zero. Applications
using this field should check the driver name and version, see
:ref:`querycap`.
* - __u32
  - ``writebuffers``
  - Applications set this field to the desired number of buffers used
internally by the driver in :c:func:`write()` mode. Drivers
return the actual number of buffers. When an application requests
zero buffers, drivers should just return the current setting
rather than the minimum or an error code. For details see
:ref:`rw`.
* - __u32
  - ``reserved``\ [4]
  - Reserved for future extensions. Drivers and applications must set
the array to zero.

* - ``V4L2_CAP_TIMEPERFRAME``
  - 0x1000
  - The frame period can be modified by setting the ``timeperframe``
field.

* - ``V4L2_MODE_HIGHQUALITY``
  - 0x0001
  - High quality imaging mode. High quality mode is intended for still
imaging applications. The idea is to get the best possible image
quality that the hardware can deliver. It is not defined how the
driver writer may achieve that; it will depend on the hardware and
the ingenuity of the driver writer. High quality mode is a
different mode from the regular motion video capture modes. In
high quality mode:

-  The driver may be able to capture higher resolutions than for
   motion capture.

-  The driver may support fewer pixel formats than motion capture
   (eg; true color).

-  The driver may capture and arithmetically combine multiple
   successive fields or frames to remove color edge artifacts and
   reduce the noise in the video data.

-  The driver may capture images in slices like a scanner in order
   to handle larger format images than would otherwise be
   possible.

-  An image capture operation may be significantly slower than
   motion capture.

-  Moving objects in the image might have excessive motion blur.

-  Capture might only work through the :c:func:`read()` call.