58 lines
2.1 KiB
ReStructuredText
58 lines
2.1 KiB
ReStructuredText
|
.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
|
||
|
|
|
||
|
|
.. _image-process-controls:
|
||
|
|
|
||
|
|
*******************************
|
||
|
|
Image Process Control Reference
|
||
|
|
*******************************
|
||
|
|
|
||
|
|
The Image Process control class is intended for low-level control of
|
||
|
|
image processing functions. Unlike ``V4L2_CID_IMAGE_SOURCE_CLASS``, the
|
||
|
|
controls in this class affect processing the image, and do not control
|
||
|
|
capturing of it.
|
||
|
|
|
||
|
|
|
||
|
|
.. _image-process-control-id:
|
||
|
|
|
||
|
|
Image Process Control IDs
|
||
|
|
=========================
|
||
|
|
|
||
|
|
``V4L2_CID_IMAGE_PROC_CLASS (class)``
|
||
|
|
The IMAGE_PROC class descriptor.
|
||
|
|
|
||
|
|
.. _v4l2-cid-link-freq:
|
||
|
|
|
||
|
|
``V4L2_CID_LINK_FREQ (integer menu)``
|
||
|
|
The frequency of the data bus (e.g. parallel or CSI-2).
|
||
|
|
|
||
|
|
.. _v4l2-cid-pixel-rate:
|
||
|
|
|
||
|
|
``V4L2_CID_PIXEL_RATE (64-bit integer)``
|
||
|
|
Pixel sampling rate in the device's pixel array. This control is
|
||
|
|
read-only and its unit is pixels / second.
|
||
|
|
|
||
|
|
Some devices use horizontal and vertical balanking to configure the frame
|
||
|
|
rate. The frame rate can be calculated from the pixel rate, analogue crop
|
||
|
|
rectangle as well as horizontal and vertical blanking. The pixel rate
|
||
|
|
control may be present in a different sub-device than the blanking controls
|
||
|
|
and the analogue crop rectangle configuration.
|
||
|
|
|
||
|
|
The configuration of the frame rate is performed by selecting the desired
|
||
|
|
horizontal and vertical blanking. The unit of this control is Hz.
|
||
|
|
|
||
|
|
``V4L2_CID_TEST_PATTERN (menu)``
|
||
|
|
Some capture/display/sensor devices have the capability to generate
|
||
|
|
test pattern images. These hardware specific test patterns can be
|
||
|
|
used to test if a device is working properly.
|
||
|
|
|
||
|
|
``V4L2_CID_DEINTERLACING_MODE (menu)``
|
||
|
|
The video deinterlacing mode (such as Bob, Weave, ...). The menu items are
|
||
|
|
driver specific and are documented in :ref:`uapi-v4l-drivers`.
|
||
|
|
|
||
|
|
``V4L2_CID_DIGITAL_GAIN (integer)``
|
||
|
|
Digital gain is the value by which all colour components
|
||
|
|
are multiplied by. Typically the digital gain applied is the
|
||
|
|
control value divided by e.g. 0x100, meaning that to get no
|
||
|
|
digital gain the control value needs to be 0x100. The no-gain
|
||
|
|
configuration is also typically the default.
|