media: zoran: move documentation file to the right place
The zoran revert patch misplaced the Zoran doc file. Move it to the right place. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Mauro Carvalho Chehab
@@ -25,6 +25,7 @@ Video4Linux (V4L) drivers
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sh_mobile_ceu_camera
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tuners
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vimc-devel
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zoran
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Digital TV drivers
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575
Documentation/driver-api/media/drivers/v4l-drivers/zoran.rst
Normal file
575
Documentation/driver-api/media/drivers/v4l-drivers/zoran.rst
Normal file
@@ -0,0 +1,575 @@
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.. SPDX-License-Identifier: GPL-2.0
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The Zoran driver
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================
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unified zoran driver (zr360x7, zoran, buz, dc10(+), dc30(+), lml33)
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website: http://mjpeg.sourceforge.net/driver-zoran/
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Frequently Asked Questions
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--------------------------
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What cards are supported
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------------------------
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Iomega Buz, Linux Media Labs LML33/LML33R10, Pinnacle/Miro
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DC10/DC10+/DC30/DC30+ and related boards (available under various names).
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Iomega Buz
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~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36060 MJPEG codec
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* Philips saa7111 TV decoder
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* Philips saa7185 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, saa7111, saa7185, zr36060, zr36067
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Inputs/outputs: Composite and S-video
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Norms: PAL, SECAM (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps)
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Card number: 7
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AverMedia 6 Eyes AVS6EYES
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~~~~~~~~~~~~~~~~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36060 MJPEG codec
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* Samsung ks0127 TV decoder
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* Conexant bt866 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, ks0127, bt866, zr36060, zr36067
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Inputs/outputs:
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Six physical inputs. 1-6 are composite,
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1-2, 3-4, 5-6 doubles as S-video,
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1-3 triples as component.
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One composite output.
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Norms: PAL, SECAM (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps)
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Card number: 8
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.. note::
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Not autodetected, card=8 is necessary.
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Linux Media Labs LML33
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~~~~~~~~~~~~~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36060 MJPEG codec
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* Brooktree bt819 TV decoder
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* Brooktree bt856 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, bt819, bt856, zr36060, zr36067
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Inputs/outputs: Composite and S-video
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Norms: PAL (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps)
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Card number: 5
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Linux Media Labs LML33R10
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~~~~~~~~~~~~~~~~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36060 MJPEG codec
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* Philips saa7114 TV decoder
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* Analog Devices adv7170 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, saa7114, adv7170, zr36060, zr36067
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Inputs/outputs: Composite and S-video
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Norms: PAL (720x576 @ 25 fps), NTSC (720x480 @ 29.97 fps)
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Card number: 6
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Pinnacle/Miro DC10(new)
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~~~~~~~~~~~~~~~~~~~~~~~
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* Zoran zr36057 PCI controller
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* Zoran zr36060 MJPEG codec
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* Philips saa7110a TV decoder
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* Analog Devices adv7176 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, saa7110, adv7175, zr36060, zr36067
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Inputs/outputs: Composite, S-video and Internal
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Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps)
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Card number: 1
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Pinnacle/Miro DC10+
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~~~~~~~~~~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36060 MJPEG codec
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* Philips saa7110a TV decoder
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* Analog Devices adv7176 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, saa7110, adv7175, zr36060, zr36067
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Inputs/outputs: Composite, S-video and Internal
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Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps)
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Card number: 2
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Pinnacle/Miro DC10(old)
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~~~~~~~~~~~~~~~~~~~~~~~
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* Zoran zr36057 PCI controller
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* Zoran zr36050 MJPEG codec
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* Zoran zr36016 Video Front End or Fuji md0211 Video Front End (clone?)
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* Micronas vpx3220a TV decoder
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* mse3000 TV encoder or Analog Devices adv7176 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, vpx3220, mse3000/adv7175, zr36050, zr36016, zr36067
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Inputs/outputs: Composite, S-video and Internal
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Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps)
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Card number: 0
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Pinnacle/Miro DC30
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~~~~~~~~~~~~~~~~~~
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* Zoran zr36057 PCI controller
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* Zoran zr36050 MJPEG codec
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* Zoran zr36016 Video Front End
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* Micronas vpx3225d/vpx3220a/vpx3216b TV decoder
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* Analog Devices adv7176 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, vpx3220/vpx3224, adv7175, zr36050, zr36016, zr36067
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Inputs/outputs: Composite, S-video and Internal
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Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps)
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Card number: 3
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Pinnacle/Miro DC30+
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~~~~~~~~~~~~~~~~~~~
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* Zoran zr36067 PCI controller
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* Zoran zr36050 MJPEG codec
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* Zoran zr36016 Video Front End
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* Micronas vpx3225d/vpx3220a/vpx3216b TV decoder
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* Analog Devices adv7176 TV encoder
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Drivers to use: videodev, i2c-core, i2c-algo-bit,
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videocodec, vpx3220/vpx3224, adv7175, zr36050, zr36015, zr36067
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Inputs/outputs: Composite, S-video and Internal
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Norms: PAL, SECAM (768x576 @ 25 fps), NTSC (640x480 @ 29.97 fps)
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Card number: 4
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.. note::
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#) No module for the mse3000 is available yet
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#) No module for the vpx3224 is available yet
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1.1 What the TV decoder can do an what not
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------------------------------------------
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The best know TV standards are NTSC/PAL/SECAM. but for decoding a frame that
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information is not enough. There are several formats of the TV standards.
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And not every TV decoder is able to handle every format. Also the every
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combination is supported by the driver. There are currently 11 different
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tv broadcast formats all aver the world.
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The CCIR defines parameters needed for broadcasting the signal.
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The CCIR has defined different standards: A,B,D,E,F,G,D,H,I,K,K1,L,M,N,...
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The CCIR says not much about the colorsystem used !!!
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And talking about a colorsystem says not to much about how it is broadcast.
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The CCIR standards A,E,F are not used any more.
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When you speak about NTSC, you usually mean the standard: CCIR - M using
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the NTSC colorsystem which is used in the USA, Japan, Mexico, Canada
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and a few others.
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When you talk about PAL, you usually mean: CCIR - B/G using the PAL
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colorsystem which is used in many Countries.
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When you talk about SECAM, you mean: CCIR - L using the SECAM Colorsystem
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which is used in France, and a few others.
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There the other version of SECAM, CCIR - D/K is used in Bulgaria, China,
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Slovakai, Hungary, Korea (Rep.), Poland, Rumania and a others.
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The CCIR - H uses the PAL colorsystem (sometimes SECAM) and is used in
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Egypt, Libya, Sri Lanka, Syrain Arab. Rep.
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The CCIR - I uses the PAL colorsystem, and is used in Great Britain, Hong Kong,
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Ireland, Nigeria, South Africa.
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The CCIR - N uses the PAL colorsystem and PAL frame size but the NTSC framerate,
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and is used in Argentinia, Uruguay, an a few others
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We do not talk about how the audio is broadcast !
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A rather good sites about the TV standards are:
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http://www.sony.jp/support/
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http://info.electronicwerkstatt.de/bereiche/fernsehtechnik/frequenzen_und_normen/Fernsehnormen/
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and http://www.cabl.com/restaurant/channel.html
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Other weird things around: NTSC 4.43 is a modificated NTSC, which is mainly
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used in PAL VCR's that are able to play back NTSC. PAL 60 seems to be the same
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as NTSC 4.43 . The Datasheets also talk about NTSC 44, It seems as if it would
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be the same as NTSC 4.43.
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NTSC Combs seems to be a decoder mode where the decoder uses a comb filter
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to split coma and luma instead of a Delay line.
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But I did not defiantly find out what NTSC Comb is.
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Philips saa7111 TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1997, is used in the BUZ and
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- can handle: PAL B/G/H/I, PAL N, PAL M, NTSC M, NTSC N, NTSC 4.43 and SECAM
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Philips saa7110a TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1995, is used in the Pinnacle/Miro DC10(new), DC10+ and
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- can handle: PAL B/G, NTSC M and SECAM
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Philips saa7114 TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 2000, is used in the LML33R10 and
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- can handle: PAL B/G/D/H/I/N, PAL N, PAL M, NTSC M, NTSC 4.43 and SECAM
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Brooktree bt819 TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1996, and is used in the LML33 and
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- can handle: PAL B/D/G/H/I, NTSC M
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Micronas vpx3220a TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1996, is used in the DC30 and DC30+ and
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- can handle: PAL B/G/H/I, PAL N, PAL M, NTSC M, NTSC 44, PAL 60, SECAM,NTSC Comb
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Samsung ks0127 TV decoder
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~~~~~~~~~~~~~~~~~~~~~~~~~
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- is used in the AVS6EYES card and
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- can handle: NTSC-M/N/44, PAL-M/N/B/G/H/I/D/K/L and SECAM
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What the TV encoder can do an what not
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--------------------------------------
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The TV encoder is doing the "same" as the decoder, but in the other direction.
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You feed them digital data and the generate a Composite or SVHS signal.
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For information about the colorsystems and TV norm take a look in the
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TV decoder section.
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Philips saa7185 TV Encoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1996, is used in the BUZ
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- can generate: PAL B/G, NTSC M
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Brooktree bt856 TV Encoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1994, is used in the LML33
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- can generate: PAL B/D/G/H/I/N, PAL M, NTSC M, PAL-N (Argentina)
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Analog Devices adv7170 TV Encoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 2000, is used in the LML300R10
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- can generate: PAL B/D/G/H/I/N, PAL M, NTSC M, PAL 60
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Analog Devices adv7175 TV Encoder
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1996, is used in the DC10, DC10+, DC10 old, DC30, DC30+
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- can generate: PAL B/D/G/H/I/N, PAL M, NTSC M
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ITT mse3000 TV encoder
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~~~~~~~~~~~~~~~~~~~~~~
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- was introduced in 1991, is used in the DC10 old
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- can generate: PAL , NTSC , SECAM
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Conexant bt866 TV encoder
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~~~~~~~~~~~~~~~~~~~~~~~~~
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- is used in AVS6EYES, and
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- can generate: NTSC/PAL, PALM, PALN
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The adv717x, should be able to produce PAL N. But you find nothing PAL N
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specific in the registers. Seem that you have to reuse a other standard
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to generate PAL N, maybe it would work if you use the PAL M settings.
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How do I get this damn thing to work
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------------------------------------
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Load zr36067.o. If it can't autodetect your card, use the card=X insmod
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option with X being the card number as given in the previous section.
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To have more than one card, use card=X1[,X2[,X3,[X4[..]]]]
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To automate this, add the following to your /etc/modprobe.d/zoran.conf:
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options zr36067 card=X1[,X2[,X3[,X4[..]]]]
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alias char-major-81-0 zr36067
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One thing to keep in mind is that this doesn't load zr36067.o itself yet. It
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just automates loading. If you start using xawtv, the device won't load on
|
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some systems, since you're trying to load modules as a user, which is not
|
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allowed ("permission denied"). A quick workaround is to add 'Load "v4l"' to
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XF86Config-4 when you use X by default, or to run 'v4l-conf -c <device>' in
|
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one of your startup scripts (normally rc.local) if you don't use X. Both
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make sure that the modules are loaded on startup, under the root account.
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What mainboard should I use (or why doesn't my card work)
|
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---------------------------------------------------------
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<insert lousy disclaimer here>. In short: good=SiS/Intel, bad=VIA.
|
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|
||||
Experience tells us that people with a Buz, on average, have more problems
|
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than users with a DC10+/LML33. Also, it tells us that people owning a VIA-
|
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based mainboard (ktXXX, MVP3) have more problems than users with a mainboard
|
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based on a different chipset. Here's some notes from Andrew Stevens:
|
||||
|
||||
Here's my experience of using LML33 and Buz on various motherboards:
|
||||
|
||||
- VIA MVP3
|
||||
- Forget it. Pointless. Doesn't work.
|
||||
- Intel 430FX (Pentium 200)
|
||||
- LML33 perfect, Buz tolerable (3 or 4 frames dropped per movie)
|
||||
- Intel 440BX (early stepping)
|
||||
- LML33 tolerable. Buz starting to get annoying (6-10 frames/hour)
|
||||
- Intel 440BX (late stepping)
|
||||
- Buz tolerable, LML3 almost perfect (occasional single frame drops)
|
||||
- SiS735
|
||||
- LML33 perfect, Buz tolerable.
|
||||
- VIA KT133(*)
|
||||
- LML33 starting to get annoying, Buz poor enough that I have up.
|
||||
|
||||
- Both 440BX boards were dual CPU versions.
|
||||
|
||||
Bernhard Praschinger later added:
|
||||
|
||||
- AMD 751
|
||||
- Buz perfect-tolerable
|
||||
- AMD 760
|
||||
- Buz perfect-tolerable
|
||||
|
||||
In general, people on the user mailinglist won't give you much of a chance
|
||||
if you have a VIA-based motherboard. They may be cheap, but sometimes, you'd
|
||||
rather want to spend some more money on better boards. In general, VIA
|
||||
mainboard's IDE/PCI performance will also suck badly compared to others.
|
||||
You'll noticed the DC10+/DC30+ aren't mentioned anywhere in the overview.
|
||||
Basically, you can assume that if the Buz works, the LML33 will work too. If
|
||||
the LML33 works, the DC10+/DC30+ will work too. They're most tolerant to
|
||||
different mainboard chipsets from all of the supported cards.
|
||||
|
||||
If you experience timeouts during capture, buy a better mainboard or lower
|
||||
the quality/buffersize during capture (see 'Concerning buffer sizes, quality,
|
||||
output size etc.'). If it hangs, there's little we can do as of now. Check
|
||||
your IRQs and make sure the card has its own interrupts.
|
||||
|
||||
Programming interface
|
||||
---------------------
|
||||
|
||||
This driver conforms to video4linux2. Support for V4L1 and for the custom
|
||||
zoran ioctls has been removed in kernel 2.6.38.
|
||||
|
||||
For programming example, please, look at lavrec.c and lavplay.c code in
|
||||
the MJPEG-tools (http://mjpeg.sf.net/).
|
||||
|
||||
Additional notes for software developers:
|
||||
|
||||
The driver returns maxwidth and maxheight parameters according to
|
||||
the current TV standard (norm). Therefore, the software which
|
||||
communicates with the driver and "asks" for these parameters should
|
||||
first set the correct norm. Well, it seems logically correct: TV
|
||||
standard is "more constant" for current country than geometry
|
||||
settings of a variety of TV capture cards which may work in ITU or
|
||||
square pixel format.
|
||||
|
||||
Applications
|
||||
------------
|
||||
|
||||
Applications known to work with this driver:
|
||||
|
||||
TV viewing:
|
||||
|
||||
* xawtv
|
||||
* kwintv
|
||||
* probably any TV application that supports video4linux or video4linux2.
|
||||
|
||||
MJPEG capture/playback:
|
||||
|
||||
* mjpegtools/lavtools (or Linux Video Studio)
|
||||
* gstreamer
|
||||
* mplayer
|
||||
|
||||
General raw capture:
|
||||
|
||||
* xawtv
|
||||
* gstreamer
|
||||
* probably any application that supports video4linux or video4linux2
|
||||
|
||||
Video editing:
|
||||
|
||||
* Cinelerra
|
||||
* MainActor
|
||||
* mjpegtools (or Linux Video Studio)
|
||||
|
||||
|
||||
Concerning buffer sizes, quality, output size etc.
|
||||
--------------------------------------------------
|
||||
|
||||
|
||||
The zr36060 can do 1:2 JPEG compression. This is really the theoretical
|
||||
maximum that the chipset can reach. The driver can, however, limit compression
|
||||
to a maximum (size) of 1:4. The reason for this is that some cards (e.g. Buz)
|
||||
can't handle 1:2 compression without stopping capture after only a few minutes.
|
||||
With 1:4, it'll mostly work. If you have a Buz, use 'low_bitrate=1' to go into
|
||||
1:4 max. compression mode.
|
||||
|
||||
100% JPEG quality is thus 1:2 compression in practice. So for a full PAL frame
|
||||
(size 720x576). The JPEG fields are stored in YUY2 format, so the size of the
|
||||
fields are 720x288x16/2 bits/field (2 fields/frame) = 207360 bytes/field x 2 =
|
||||
414720 bytes/frame (add some more bytes for headers and DHT (huffman)/DQT
|
||||
(quantization) tables, and you'll get to something like 512kB per frame for
|
||||
1:2 compression. For 1:4 compression, you'd have frames of half this size.
|
||||
|
||||
Some additional explanation by Martin Samuelsson, which also explains the
|
||||
importance of buffer sizes:
|
||||
--
|
||||
> Hmm, I do not think it is really that way. With the current (downloaded
|
||||
> at 18:00 Monday) driver I get that output sizes for 10 sec:
|
||||
> -q 50 -b 128 : 24.283.332 Bytes
|
||||
> -q 50 -b 256 : 48.442.368
|
||||
> -q 25 -b 128 : 24.655.992
|
||||
> -q 25 -b 256 : 25.859.820
|
||||
|
||||
I woke up, and can't go to sleep again. I'll kill some time explaining why
|
||||
this doesn't look strange to me.
|
||||
|
||||
Let's do some math using a width of 704 pixels. I'm not sure whether the Buz
|
||||
actually use that number or not, but that's not too important right now.
|
||||
|
||||
704x288 pixels, one field, is 202752 pixels. Divided by 64 pixels per block;
|
||||
3168 blocks per field. Each pixel consist of two bytes; 128 bytes per block;
|
||||
1024 bits per block. 100% in the new driver mean 1:2 compression; the maximum
|
||||
output becomes 512 bits per block. Actually 510, but 512 is simpler to use
|
||||
for calculations.
|
||||
|
||||
Let's say that we specify d1q50. We thus want 256 bits per block; times 3168
|
||||
becomes 811008 bits; 101376 bytes per field. We're talking raw bits and bytes
|
||||
here, so we don't need to do any fancy corrections for bits-per-pixel or such
|
||||
things. 101376 bytes per field.
|
||||
|
||||
d1 video contains two fields per frame. Those sum up to 202752 bytes per
|
||||
frame, and one of those frames goes into each buffer.
|
||||
|
||||
But wait a second! -b128 gives 128kB buffers! It's not possible to cram
|
||||
202752 bytes of JPEG data into 128kB!
|
||||
|
||||
This is what the driver notice and automatically compensate for in your
|
||||
examples. Let's do some math using this information:
|
||||
|
||||
128kB is 131072 bytes. In this buffer, we want to store two fields, which
|
||||
leaves 65536 bytes for each field. Using 3168 blocks per field, we get
|
||||
20.68686868... available bytes per block; 165 bits. We can't allow the
|
||||
request for 256 bits per block when there's only 165 bits available! The -q50
|
||||
option is silently overridden, and the -b128 option takes precedence, leaving
|
||||
us with the equivalence of -q32.
|
||||
|
||||
This gives us a data rate of 165 bits per block, which, times 3168, sums up
|
||||
to 65340 bytes per field, out of the allowed 65536. The current driver has
|
||||
another level of rate limiting; it won't accept -q values that fill more than
|
||||
6/8 of the specified buffers. (I'm not sure why. "Playing it safe" seem to be
|
||||
a safe bet. Personally, I think I would have lowered requested-bits-per-block
|
||||
by one, or something like that.) We can't use 165 bits per block, but have to
|
||||
lower it again, to 6/8 of the available buffer space: We end up with 124 bits
|
||||
per block, the equivalence of -q24. With 128kB buffers, you can't use greater
|
||||
than -q24 at -d1. (And PAL, and 704 pixels width...)
|
||||
|
||||
The third example is limited to -q24 through the same process. The second
|
||||
example, using very similar calculations, is limited to -q48. The only
|
||||
example that actually grab at the specified -q value is the last one, which
|
||||
is clearly visible, looking at the file size.
|
||||
--
|
||||
|
||||
Conclusion: the quality of the resulting movie depends on buffer size, quality,
|
||||
whether or not you use 'low_bitrate=1' as insmod option for the zr36060.c
|
||||
module to do 1:4 instead of 1:2 compression, etc.
|
||||
|
||||
If you experience timeouts, lowering the quality/buffersize or using
|
||||
'low_bitrate=1 as insmod option for zr36060.o might actually help, as is
|
||||
proven by the Buz.
|
||||
|
||||
It hangs/crashes/fails/whatevers! Help!
|
||||
---------------------------------------
|
||||
|
||||
Make sure that the card has its own interrupts (see /proc/interrupts), check
|
||||
the output of dmesg at high verbosity (load zr36067.o with debug=2,
|
||||
load all other modules with debug=1). Check that your mainboard is favorable
|
||||
(see question 2) and if not, test the card in another computer. Also see the
|
||||
notes given in question 3 and try lowering quality/buffersize/capturesize
|
||||
if recording fails after a period of time.
|
||||
|
||||
If all this doesn't help, give a clear description of the problem including
|
||||
detailed hardware information (memory+brand, mainboard+chipset+brand, which
|
||||
MJPEG card, processor, other PCI cards that might be of interest), give the
|
||||
system PnP information (/proc/interrupts, /proc/dma, /proc/devices), and give
|
||||
the kernel version, driver version, glibc version, gcc version and any other
|
||||
information that might possibly be of interest. Also provide the dmesg output
|
||||
at high verbosity. See 'Contacting' on how to contact the developers.
|
||||
|
||||
Maintainers/Contacting
|
||||
----------------------
|
||||
|
||||
Previous maintainers/developers of this driver are
|
||||
- Laurent Pinchart <laurent.pinchart@skynet.be>
|
||||
- Ronald Bultje rbultje@ronald.bitfreak.net
|
||||
- Serguei Miridonov <mirsev@cicese.mx>
|
||||
- Wolfgang Scherr <scherr@net4you.net>
|
||||
- Dave Perks <dperks@ibm.net>
|
||||
- Rainer Johanni <Rainer@Johanni.de>
|
||||
|
||||
Driver's License
|
||||
----------------
|
||||
|
||||
This driver is distributed under the terms of the General Public License.
|
||||
|
||||
This program is free software; you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation; either version 2 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
See http://www.gnu.org/ for more information.
|
||||
Reference in New Issue
Block a user