2020-08-26 15:03:09 +08:00
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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
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2018-08-30 22:15:26 +08:00
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2016-06-30 21:18:56 +08:00
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.. _dvb_video:
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2017-09-02 00:28:16 +08:00
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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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2016-06-30 21:18:56 +08:00
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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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2017-09-02 00:28:16 +08:00
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Note that the Digital TV video device only controls decoding of the MPEG video
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2016-06-30 21:18:56 +08:00
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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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2017-09-02 00:28:16 +08:00
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Some Digital TV cards don’t have their own MPEG decoder, which results in the
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2016-06-30 21:18:56 +08:00
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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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