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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. _common:
###################
Common API Elements
###################
Programming a V4L2 device consists of these steps:
- Opening the device
- Changing device properties, selecting a video and audio input, video
standard, picture brightness a. o.
- Negotiating a data format
- Negotiating an input/output method
- The actual input/output loop
- Closing the device
In practice most steps are optional and can be executed out of order. It
depends on the V4L2 device type, you can read about the details in
:ref:`devices`. In this chapter we will discuss the basic concepts
applicable to all devices.
.. toctree::
:maxdepth: 1
open
querycap
app-pri
video
audio
tuner
standard
dv-timings
control
extended-controls
ext-ctrls-camera
ext-ctrls-flash
ext-ctrls-image-source
ext-ctrls-image-process
ext-ctrls-codec
ext-ctrls-codec-stateless
ext-ctrls-jpeg
ext-ctrls-dv
ext-ctrls-rf-tuner
ext-ctrls-fm-tx
ext-ctrls-fm-rx
ext-ctrls-detect
ext-ctrls-colorimetry
fourcc
format
planar-apis
selection-api
crop
streaming-par
|
