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.. Permission is granted to copy, distribute and/or modify this
.. document under the terms of the GNU Free Documentation License,
.. Version 1.1 or any later version published by the Free Software
.. Foundation, with no Invariant Sections, no Front-Cover Texts
.. and no Back-Cover Texts. A copy of the license is included at
.. Documentation/media/uapi/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
.. _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-jpeg
ext-ctrls-dv
ext-ctrls-rf-tuner
ext-ctrls-fm-tx
ext-ctrls-fm-rx
ext-ctrls-detect
format
planar-apis
selection-api
crop
streaming-par
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