Common API Elements

.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later .. c:namespace:: V4L

.. _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