1.. SPDX-License-Identifier: GPL-2.0 2 3The ivtv driver 4=============== 5 6Author: Hans Verkuil <hverkuil@xs4all.nl> 7 8This is a v4l2 device driver for the Conexant cx23415/6 MPEG encoder/decoder. 9The cx23415 can do both encoding and decoding, the cx23416 can only do MPEG 10encoding. Currently the only card featuring full decoding support is the 11Hauppauge PVR-350. 12 13.. note:: 14 15 #) This driver requires the latest encoder firmware (version 2.06.039, size 16 376836 bytes). Get the firmware from here: 17 18 https://linuxtv.org/downloads/firmware/#conexant 19 20 #) 'normal' TV applications do not work with this driver, you need 21 an application that can handle MPEG input such as mplayer, xine, MythTV, 22 etc. 23 24The primary goal of the IVTV project is to provide a "clean room" Linux 25Open Source driver implementation for video capture cards based on the 26iCompression iTVC15 or Conexant CX23415/CX23416 MPEG Codec. 27 28Features 29-------- 30 31 * Hardware mpeg2 capture of broadcast video (and sound) via the tuner or 32 S-Video/Composite and audio line-in. 33 * Hardware mpeg2 capture of FM radio where hardware support exists 34 * Supports NTSC, PAL, SECAM with stereo sound 35 * Supports SAP and bilingual transmissions. 36 * Supports raw VBI (closed captions and teletext). 37 * Supports sliced VBI (closed captions and teletext) and is able to insert 38 this into the captured MPEG stream. 39 * Supports raw YUV and PCM input. 40 41Additional features for the PVR-350 (CX23415 based) 42--------------------------------------------------- 43 44 * Provides hardware mpeg2 playback 45 * Provides comprehensive OSD (On Screen Display: ie. graphics overlaying the 46 video signal) 47 * Provides a framebuffer (allowing X applications to appear on the video 48 device) 49 * Supports raw YUV output. 50 51IMPORTANT: In case of problems first read this page: 52 https://help.ubuntu.com/community/Install_IVTV_Troubleshooting 53 54See also 55-------- 56 57https://linuxtv.org 58 59IRC 60--- 61 62irc://irc.freenode.net/#v4l 63 64---------------------------------------------------------- 65 66Devices 67------- 68 69A maximum of 12 ivtv boards are allowed at the moment. 70 71Cards that don't have a video output capability (i.e. non PVR350 cards) 72lack the vbi8, vbi16, video16 and video48 devices. They also do not 73support the framebuffer device /dev/fbx for OSD. 74 75The radio0 device may or may not be present, depending on whether the 76card has a radio tuner or not. 77 78Here is a list of the base v4l devices: 79 80.. code-block:: none 81 82 crw-rw---- 1 root video 81, 0 Jun 19 22:22 /dev/video0 83 crw-rw---- 1 root video 81, 16 Jun 19 22:22 /dev/video16 84 crw-rw---- 1 root video 81, 24 Jun 19 22:22 /dev/video24 85 crw-rw---- 1 root video 81, 32 Jun 19 22:22 /dev/video32 86 crw-rw---- 1 root video 81, 48 Jun 19 22:22 /dev/video48 87 crw-rw---- 1 root video 81, 64 Jun 19 22:22 /dev/radio0 88 crw-rw---- 1 root video 81, 224 Jun 19 22:22 /dev/vbi0 89 crw-rw---- 1 root video 81, 228 Jun 19 22:22 /dev/vbi8 90 crw-rw---- 1 root video 81, 232 Jun 19 22:22 /dev/vbi16 91 92Base devices 93------------ 94 95For every extra card you have the numbers increased by one. For example, 96/dev/video0 is listed as the 'base' encoding capture device so we have: 97 98- /dev/video0 is the encoding capture device for the first card (card 0) 99- /dev/video1 is the encoding capture device for the second card (card 1) 100- /dev/video2 is the encoding capture device for the third card (card 2) 101 102Note that if the first card doesn't have a feature (eg no decoder, so no 103video16, the second card will still use video17. The simple rule is 'add 104the card number to the base device number'. If you have other capture 105cards (e.g. WinTV PCI) that are detected first, then you have to tell 106the ivtv module about it so that it will start counting at 1 (or 2, or 107whatever). Otherwise the device numbers can get confusing. The ivtv 108'ivtv_first_minor' module option can be used for that. 109 110 111- /dev/video0 112 113 The encoding capture device(s). 114 115 Read-only. 116 117 Reading from this device gets you the MPEG1/2 program stream. 118 Example: 119 120 .. code-block:: none 121 122 cat /dev/video0 > my.mpg (you need to hit ctrl-c to exit) 123 124 125- /dev/video16 126 127 The decoder output device(s) 128 129 Write-only. Only present if the MPEG decoder (i.e. CX23415) exists. 130 131 An mpeg2 stream sent to this device will appear on the selected video 132 display, audio will appear on the line-out/audio out. It is only 133 available for cards that support video out. Example: 134 135 .. code-block:: none 136 137 cat my.mpg >/dev/video16 138 139 140- /dev/video24 141 142 The raw audio capture device(s). 143 144 Read-only 145 146 The raw audio PCM stereo stream from the currently selected 147 tuner or audio line-in. Reading from this device results in a raw 148 (signed 16 bit Little Endian, 48000 Hz, stereo pcm) capture. 149 This device only captures audio. This should be replaced by an ALSA 150 device in the future. 151 Note that there is no corresponding raw audio output device, this is 152 not supported in the decoder firmware. 153 154 155- /dev/video32 156 157 The raw video capture device(s) 158 159 Read-only 160 161 The raw YUV video output from the current video input. The YUV format 162 is a 16x16 linear tiled NV12 format (V4L2_PIX_FMT_NV12_16L16) 163 164 Note that the YUV and PCM streams are not synchronized, so they are of 165 limited use. 166 167 168- /dev/video48 169 170 The raw video display device(s) 171 172 Write-only. Only present if the MPEG decoder (i.e. CX23415) exists. 173 174 Writes a YUV stream to the decoder of the card. 175 176 177- /dev/radio0 178 179 The radio tuner device(s) 180 181 Cannot be read or written. 182 183 Used to enable the radio tuner and tune to a frequency. You cannot 184 read or write audio streams with this device. Once you use this 185 device to tune the radio, use /dev/video24 to read the raw pcm stream 186 or /dev/video0 to get an mpeg2 stream with black video. 187 188 189- /dev/vbi0 190 191 The 'vertical blank interval' (Teletext, CC, WSS etc) capture device(s) 192 193 Read-only 194 195 Captures the raw (or sliced) video data sent during the Vertical Blank 196 Interval. This data is used to encode teletext, closed captions, VPS, 197 widescreen signalling, electronic program guide information, and other 198 services. 199 200 201- /dev/vbi8 202 203 Processed vbi feedback device(s) 204 205 Read-only. Only present if the MPEG decoder (i.e. CX23415) exists. 206 207 The sliced VBI data embedded in an MPEG stream is reproduced on this 208 device. So while playing back a recording on /dev/video16, you can 209 read the embedded VBI data from /dev/vbi8. 210 211 212- /dev/vbi16 213 214 The vbi 'display' device(s) 215 216 Write-only. Only present if the MPEG decoder (i.e. CX23415) exists. 217 218 Can be used to send sliced VBI data to the video-out connector. 219