From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/video4linux/README.ivtv | 186 ++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 Documentation/video4linux/README.ivtv (limited to 'Documentation/video4linux/README.ivtv') diff --git a/Documentation/video4linux/README.ivtv b/Documentation/video4linux/README.ivtv new file mode 100644 index 00000000..2579b5b7 --- /dev/null +++ b/Documentation/video4linux/README.ivtv @@ -0,0 +1,186 @@ + +ivtv release notes +================== + +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: + +http://dl.ivtvdriver.org/ivtv/firmware/ + +NOTE: '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: + http://www.ivtvdriver.org/index.php/Troubleshooting + +See also: + +Homepage + Wiki +http://www.ivtvdriver.org + +IRC +irc://irc.freenode.net/ivtv-dev + +---------------------------------------------------------- + +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: +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: + +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: + +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. + +--------------------------------- + +Hans Verkuil -- cgit v1.2.3