2020-08-26 09:03:09 +02:00
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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
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2018-08-30 10:15:26 -04:00
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2016-06-30 15:18:56 +02:00
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.. _common:
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###################
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Common API Elements
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###################
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Programming a V4L2 device consists of these steps:
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- Opening the device
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- Changing device properties, selecting a video and audio input, video
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standard, picture brightness a. o.
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- Negotiating a data format
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- Negotiating an input/output method
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- The actual input/output loop
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- Closing the device
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In practice most steps are optional and can be executed out of order. It
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depends on the V4L2 device type, you can read about the details in
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:ref:`devices`. In this chapter we will discuss the basic concepts
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applicable to all devices.
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.. toctree::
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:maxdepth: 1
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open
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querycap
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app-pri
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video
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audio
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tuner
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standard
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dv-timings
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2016-07-02 08:37:16 -03:00
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control
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extended-controls
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2019-02-08 10:53:50 +01:00
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ext-ctrls-camera
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ext-ctrls-flash
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ext-ctrls-image-source
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ext-ctrls-image-process
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ext-ctrls-codec
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2020-11-26 10:36:18 +01:00
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ext-ctrls-codec-stateless
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2019-02-08 10:53:50 +01:00
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ext-ctrls-jpeg
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ext-ctrls-dv
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ext-ctrls-rf-tuner
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ext-ctrls-fm-tx
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ext-ctrls-fm-rx
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ext-ctrls-detect
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2020-03-06 08:34:41 +01:00
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fourcc
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2016-06-30 15:18:56 +02:00
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format
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planar-apis
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selection-api
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2018-05-14 07:27:24 -04:00
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crop
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2016-06-30 15:18:56 +02:00
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streaming-par
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