forked from Minki/linux
f2ac8ce823
All Documentation files outside the uAPI are all licensed with, at least, GPL 2.0. So, mark them as such. The ondes at media/uapi are at least GFDL 1.1+. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
219 lines
6.5 KiB
ReStructuredText
219 lines
6.5 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
The ivtv driver
|
|
===============
|
|
|
|
Author: Hans Verkuil <hverkuil@xs4all.nl>
|
|
|
|
This is a v4l2 device driver for the Conexant cx23415/6 MPEG encoder/decoder.
|
|
The cx23415 can do both encoding and decoding, the cx23416 can only do MPEG
|
|
encoding. Currently the only card featuring full decoding support is the
|
|
Hauppauge PVR-350.
|
|
|
|
.. note::
|
|
|
|
#) This driver requires the latest encoder firmware (version 2.06.039, size
|
|
376836 bytes). Get the firmware from here:
|
|
|
|
https://linuxtv.org/downloads/firmware/#conexant
|
|
|
|
#) 'normal' TV applications do not work with this driver, you need
|
|
an application that can handle MPEG input such as mplayer, xine, MythTV,
|
|
etc.
|
|
|
|
The primary goal of the IVTV project is to provide a "clean room" Linux
|
|
Open Source driver implementation for video capture cards based on the
|
|
iCompression iTVC15 or Conexant CX23415/CX23416 MPEG Codec.
|
|
|
|
Features
|
|
--------
|
|
|
|
* Hardware mpeg2 capture of broadcast video (and sound) via the tuner or
|
|
S-Video/Composite and audio line-in.
|
|
* Hardware mpeg2 capture of FM radio where hardware support exists
|
|
* Supports NTSC, PAL, SECAM with stereo sound
|
|
* Supports SAP and bilingual transmissions.
|
|
* Supports raw VBI (closed captions and teletext).
|
|
* Supports sliced VBI (closed captions and teletext) and is able to insert
|
|
this into the captured MPEG stream.
|
|
* Supports raw YUV and PCM input.
|
|
|
|
Additional features for the PVR-350 (CX23415 based)
|
|
---------------------------------------------------
|
|
|
|
* Provides hardware mpeg2 playback
|
|
* Provides comprehensive OSD (On Screen Display: ie. graphics overlaying the
|
|
video signal)
|
|
* Provides a framebuffer (allowing X applications to appear on the video
|
|
device)
|
|
* Supports raw YUV output.
|
|
|
|
IMPORTANT: In case of problems first read this page:
|
|
https://help.ubuntu.com/community/Install_IVTV_Troubleshooting
|
|
|
|
See also
|
|
--------
|
|
|
|
https://linuxtv.org
|
|
|
|
IRC
|
|
---
|
|
|
|
irc://irc.freenode.net/#v4l
|
|
|
|
----------------------------------------------------------
|
|
|
|
Devices
|
|
-------
|
|
|
|
A maximum of 12 ivtv boards are allowed at the moment.
|
|
|
|
Cards that don't have a video output capability (i.e. non PVR350 cards)
|
|
lack the vbi8, vbi16, video16 and video48 devices. They also do not
|
|
support the framebuffer device /dev/fbx for OSD.
|
|
|
|
The radio0 device may or may not be present, depending on whether the
|
|
card has a radio tuner or not.
|
|
|
|
Here is a list of the base v4l devices:
|
|
|
|
.. code-block:: none
|
|
|
|
crw-rw---- 1 root video 81, 0 Jun 19 22:22 /dev/video0
|
|
crw-rw---- 1 root video 81, 16 Jun 19 22:22 /dev/video16
|
|
crw-rw---- 1 root video 81, 24 Jun 19 22:22 /dev/video24
|
|
crw-rw---- 1 root video 81, 32 Jun 19 22:22 /dev/video32
|
|
crw-rw---- 1 root video 81, 48 Jun 19 22:22 /dev/video48
|
|
crw-rw---- 1 root video 81, 64 Jun 19 22:22 /dev/radio0
|
|
crw-rw---- 1 root video 81, 224 Jun 19 22:22 /dev/vbi0
|
|
crw-rw---- 1 root video 81, 228 Jun 19 22:22 /dev/vbi8
|
|
crw-rw---- 1 root video 81, 232 Jun 19 22:22 /dev/vbi16
|
|
|
|
Base devices
|
|
------------
|
|
|
|
For every extra card you have the numbers increased by one. For example,
|
|
/dev/video0 is listed as the 'base' encoding capture device so we have:
|
|
|
|
- /dev/video0 is the encoding capture device for the first card (card 0)
|
|
- /dev/video1 is the encoding capture device for the second card (card 1)
|
|
- /dev/video2 is the encoding capture device for the third card (card 2)
|
|
|
|
Note that if the first card doesn't have a feature (eg no decoder, so no
|
|
video16, the second card will still use video17. The simple rule is 'add
|
|
the card number to the base device number'. If you have other capture
|
|
cards (e.g. WinTV PCI) that are detected first, then you have to tell
|
|
the ivtv module about it so that it will start counting at 1 (or 2, or
|
|
whatever). Otherwise the device numbers can get confusing. The ivtv
|
|
'ivtv_first_minor' module option can be used for that.
|
|
|
|
|
|
- /dev/video0
|
|
|
|
The encoding capture device(s).
|
|
|
|
Read-only.
|
|
|
|
Reading from this device gets you the MPEG1/2 program stream.
|
|
Example:
|
|
|
|
.. code-block:: none
|
|
|
|
cat /dev/video0 > my.mpg (you need to hit ctrl-c to exit)
|
|
|
|
|
|
- /dev/video16
|
|
|
|
The decoder output device(s)
|
|
|
|
Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
|
|
|
|
An mpeg2 stream sent to this device will appear on the selected video
|
|
display, audio will appear on the line-out/audio out. It is only
|
|
available for cards that support video out. Example:
|
|
|
|
.. code-block:: none
|
|
|
|
cat my.mpg >/dev/video16
|
|
|
|
|
|
- /dev/video24
|
|
|
|
The raw audio capture device(s).
|
|
|
|
Read-only
|
|
|
|
The raw audio PCM stereo stream from the currently selected
|
|
tuner or audio line-in. Reading from this device results in a raw
|
|
(signed 16 bit Little Endian, 48000 Hz, stereo pcm) capture.
|
|
This device only captures audio. This should be replaced by an ALSA
|
|
device in the future.
|
|
Note that there is no corresponding raw audio output device, this is
|
|
not supported in the decoder firmware.
|
|
|
|
|
|
- /dev/video32
|
|
|
|
The raw video capture device(s)
|
|
|
|
Read-only
|
|
|
|
The raw YUV video output from the current video input. The YUV format
|
|
is non-standard (V4L2_PIX_FMT_HM12).
|
|
|
|
Note that the YUV and PCM streams are not synchronized, so they are of
|
|
limited use.
|
|
|
|
|
|
- /dev/video48
|
|
|
|
The raw video display device(s)
|
|
|
|
Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
|
|
|
|
Writes a YUV stream to the decoder of the card.
|
|
|
|
|
|
- /dev/radio0
|
|
|
|
The radio tuner device(s)
|
|
|
|
Cannot be read or written.
|
|
|
|
Used to enable the radio tuner and tune to a frequency. You cannot
|
|
read or write audio streams with this device. Once you use this
|
|
device to tune the radio, use /dev/video24 to read the raw pcm stream
|
|
or /dev/video0 to get an mpeg2 stream with black video.
|
|
|
|
|
|
- /dev/vbi0
|
|
|
|
The 'vertical blank interval' (Teletext, CC, WSS etc) capture device(s)
|
|
|
|
Read-only
|
|
|
|
Captures the raw (or sliced) video data sent during the Vertical Blank
|
|
Interval. This data is used to encode teletext, closed captions, VPS,
|
|
widescreen signalling, electronic program guide information, and other
|
|
services.
|
|
|
|
|
|
- /dev/vbi8
|
|
|
|
Processed vbi feedback device(s)
|
|
|
|
Read-only. Only present if the MPEG decoder (i.e. CX23415) exists.
|
|
|
|
The sliced VBI data embedded in an MPEG stream is reproduced on this
|
|
device. So while playing back a recording on /dev/video16, you can
|
|
read the embedded VBI data from /dev/vbi8.
|
|
|
|
|
|
- /dev/vbi16
|
|
|
|
The vbi 'display' device(s)
|
|
|
|
Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
|
|
|
|
Can be used to send sliced VBI data to the video-out connector.
|