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Based on kernel version 3.13. Page generated on 2014-01-20 22:05 EST.

1	
2	ivtv release notes
3	==================
4	
5	This is a v4l2 device driver for the Conexant cx23415/6 MPEG encoder/decoder.
6	The cx23415 can do both encoding and decoding, the cx23416 can only do MPEG
7	encoding. Currently the only card featuring full decoding support is the
8	Hauppauge PVR-350.
9	
10	NOTE: this driver requires the latest encoder firmware (version 2.06.039, size
11	376836 bytes). Get the firmware from here:
12	
13	http://dl.ivtvdriver.org/ivtv/firmware/
14	
15	NOTE: 'normal' TV applications do not work with this driver, you need
16	an application that can handle MPEG input such as mplayer, xine, MythTV,
17	etc.
18	
19	The primary goal of the IVTV project is to provide a "clean room" Linux
20	Open Source driver implementation for video capture cards based on the
21	iCompression iTVC15 or Conexant CX23415/CX23416 MPEG Codec.
22	
23	Features:
24	 * Hardware mpeg2 capture of broadcast video (and sound) via the tuner or
25	   S-Video/Composite and audio line-in.
26	 * Hardware mpeg2 capture of FM radio where hardware support exists
27	 * Supports NTSC, PAL, SECAM with stereo sound
28	 * Supports SAP and bilingual transmissions.
29	 * Supports raw VBI (closed captions and teletext).
30	 * Supports sliced VBI (closed captions and teletext) and is able to insert
31	   this into the captured MPEG stream.
32	 * Supports raw YUV and PCM input.
33	
34	Additional features for the PVR-350 (CX23415 based):
35	 * Provides hardware mpeg2 playback
36	 * Provides comprehensive OSD (On Screen Display: ie. graphics overlaying the
37	   video signal)
38	 * Provides a framebuffer (allowing X applications to appear on the video
39	   device)
40	 * Supports raw YUV output.
41	
42	IMPORTANT: In case of problems first read this page:
43		   http://www.ivtvdriver.org/index.php/Troubleshooting
44	
45	See also:
46	
47	Homepage + Wiki
48	http://www.ivtvdriver.org
49	
50	IRC
51	irc://irc.freenode.net/ivtv-dev
52	
53	----------------------------------------------------------
54	
55	Devices
56	=======
57	
58	A maximum of 12 ivtv boards are allowed at the moment.
59	
60	Cards that don't have a video output capability (i.e. non PVR350 cards)
61	lack the vbi8, vbi16, video16 and video48 devices. They also do not
62	support the framebuffer device /dev/fbx for OSD.
63	
64	The radio0 device may or may not be present, depending on whether the
65	card has a radio tuner or not.
66	
67	Here is a list of the base v4l devices:
68	crw-rw----    1 root     video     81,   0 Jun 19 22:22 /dev/video0
69	crw-rw----    1 root     video     81,  16 Jun 19 22:22 /dev/video16
70	crw-rw----    1 root     video     81,  24 Jun 19 22:22 /dev/video24
71	crw-rw----    1 root     video     81,  32 Jun 19 22:22 /dev/video32
72	crw-rw----    1 root     video     81,  48 Jun 19 22:22 /dev/video48
73	crw-rw----    1 root     video     81,  64 Jun 19 22:22 /dev/radio0
74	crw-rw----    1 root     video     81, 224 Jun 19 22:22 /dev/vbi0
75	crw-rw----    1 root     video     81, 228 Jun 19 22:22 /dev/vbi8
76	crw-rw----    1 root     video     81, 232 Jun 19 22:22 /dev/vbi16
77	
78	Base devices
79	============
80	
81	For every extra card you have the numbers increased by one. For example,
82	/dev/video0 is listed as the 'base' encoding capture device so we have:
83	
84	 /dev/video0  is the encoding capture device for the first card (card 0)
85	 /dev/video1  is the encoding capture device for the second card (card 1)
86	 /dev/video2  is the encoding capture device for the third card (card 2)
87	
88	Note that if the first card doesn't have a feature (eg no decoder, so no
89	video16, the second card will still use video17. The simple rule is 'add
90	the card number to the base device number'. If you have other capture
91	cards (e.g. WinTV PCI) that are detected first, then you have to tell
92	the ivtv module about it so that it will start counting at 1 (or 2, or
93	whatever). Otherwise the device numbers can get confusing. The ivtv
94	'ivtv_first_minor' module option can be used for that.
95	
96	
97	/dev/video0
98	The encoding capture device(s).
99	Read-only.
100	
101	Reading from this device gets you the MPEG1/2 program stream.
102	Example:
103	
104	cat /dev/video0 > my.mpg (you need to hit ctrl-c to exit)
105	
106	
107	/dev/video16
108	The decoder output device(s)
109	Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
110	
111	An mpeg2 stream sent to this device will appear on the selected video
112	display, audio will appear on the line-out/audio out.  It is only
113	available for cards that support video out. Example:
114	
115	cat my.mpg >/dev/video16
116	
117	
118	/dev/video24
119	The raw audio capture device(s).
120	Read-only
121	
122	The raw audio PCM stereo stream from the currently selected
123	tuner or audio line-in.  Reading from this device results in a raw
124	(signed 16 bit Little Endian, 48000 Hz, stereo pcm) capture.
125	This device only captures audio. This should be replaced by an ALSA
126	device in the future.
127	Note that there is no corresponding raw audio output device, this is
128	not supported in the decoder firmware.
129	
130	
131	/dev/video32
132	The raw video capture device(s)
133	Read-only
134	
135	The raw YUV video output from the current video input. The YUV format
136	is non-standard (V4L2_PIX_FMT_HM12).
137	
138	Note that the YUV and PCM streams are not synchronized, so they are of
139	limited use.
140	
141	
142	/dev/video48
143	The raw video display device(s)
144	Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
145	
146	Writes a YUV stream to the decoder of the card.
147	
148	
149	/dev/radio0
150	The radio tuner device(s)
151	Cannot be read or written.
152	
153	Used to enable the radio tuner and tune to a frequency. You cannot
154	read or write audio streams with this device.  Once you use this
155	device to tune the radio, use /dev/video24 to read the raw pcm stream
156	or /dev/video0 to get an mpeg2 stream with black video.
157	
158	
159	/dev/vbi0
160	The 'vertical blank interval' (Teletext, CC, WSS etc) capture device(s)
161	Read-only
162	
163	Captures the raw (or sliced) video data sent during the Vertical Blank
164	Interval. This data is used to encode teletext, closed captions, VPS,
165	widescreen signalling, electronic program guide information, and other
166	services.
167	
168	
169	/dev/vbi8
170	Processed vbi feedback device(s)
171	Read-only. Only present if the MPEG decoder (i.e. CX23415) exists.
172	
173	The sliced VBI data embedded in an MPEG stream is reproduced on this
174	device. So while playing back a recording on /dev/video16, you can
175	read the embedded VBI data from /dev/vbi8.
176	
177	
178	/dev/vbi16
179	The vbi 'display' device(s)
180	Write-only. Only present if the MPEG decoder (i.e. CX23415) exists.
181	
182	Can be used to send sliced VBI data to the video-out connector.
183	
184	---------------------------------
185	
186	Hans Verkuil <hverkuil@xs4all.nl>
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