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54f38fcae5
Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee38 ("docs: Create a user-space API guide").
As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.
Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
44 lines
1.6 KiB
ReStructuredText
44 lines
1.6 KiB
ReStructuredText
.. Permission is granted to copy, distribute and/or modify this
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.. document under the terms of the GNU Free Documentation License,
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.. Version 1.1 or any later version published by the Free Software
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.. Foundation, with no Invariant Sections, no Front-Cover Texts
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.. and no Back-Cover Texts. A copy of the license is included at
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.. Documentation/userspace-api/media/fdl-appendix.rst.
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..
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.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
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.. _dvb_video:
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#######################
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Digital TV Video Device
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#######################
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The Digital TV video device controls the MPEG2 video decoder of the Digital
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TV hardware. It can be accessed through **/dev/dvb/adapter0/video0**. Data
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types and and ioctl definitions can be accessed by including
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**linux/dvb/video.h** in your application.
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Note that the Digital TV video device only controls decoding of the MPEG video
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stream, not its presentation on the TV or computer screen. On PCs this
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is typically handled by an associated video4linux device, e.g.
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**/dev/video**, which allows scaling and defining output windows.
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Some Digital TV cards don’t have their own MPEG decoder, which results in the
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omission of the audio and video device as well as the video4linux
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device.
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The ioctls that deal with SPUs (sub picture units) and navigation
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packets are only supported on some MPEG decoders made for DVD playback.
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These ioctls were also used by V4L2 to control MPEG decoders implemented
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in V4L2. The use of these ioctls for that purpose has been made obsolete
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and proper V4L2 ioctls or controls have been created to replace that
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functionality.
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.. toctree::
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:maxdepth: 1
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video_types
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video_function_calls
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