forked from Minki/linux
558 lines
22 KiB
Plaintext
558 lines
22 KiB
Plaintext
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Frequently Asked Questions:
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===========================
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subject: unified zoran driver (zr360x7, zoran, buz, dc10(+), dc30(+), lml33)
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website: http://mjpeg.sourceforge.net/driver-zoran/
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1. What cards are supported
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1.1 What the TV decoder can do an what not
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1.2 What the TV encoder can do an what not
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2. How do I get this damn thing to work
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3. What mainboard should I use (or why doesn't my card work)
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4. Programming interface
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5. Applications
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6. Concerning buffer sizes, quality, output size etc.
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7. It hangs/crashes/fails/whatevers! Help!
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8. Maintainers/Contacting
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9. License
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===========================
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1. What cards are supported
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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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* 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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Linux Media Labs LML33:
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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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* 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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* 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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* 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, sa7110, 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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* 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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* 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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* 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: No module for the mse3000 is available yet
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Note: No module for the vpx3224 is available yet
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Note: use encoder=X or decoder=X for non-default i2c chips (see i2c-id.h)
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===========================
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1.1 What the TV decoder can do an what not
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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 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/ServiceArea/Voltage_map/
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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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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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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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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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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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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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===========================
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1.2 What the TV encoder can do an what not
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The TV encoder are doing the "same" as the decoder, but in the oder 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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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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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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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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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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was introduced in 1991, is used in the DC10 old
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can generate: PAL , NTSC , SECAM
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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 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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==========================
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2. How do I get this damn thing to work
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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.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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===========================
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3. What mainboard should I use (or why doesn't my card work)
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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:
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--
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Here's my experience of using LML33 and Buz on various motherboards:
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VIA MVP3
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Forget it. Pointless. Doesn't work.
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Intel 430FX (Pentium 200)
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LML33 perfect, Buz tolerable (3 or 4 frames dropped per movie)
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Intel 440BX (early stepping)
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LML33 tolerable. Buz starting to get annoying (6-10 frames/hour)
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Intel 440BX (late stepping)
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Buz tolerable, LML3 almost perfect (occasional single frame drops)
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SiS735
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LML33 perfect, Buz tolerable.
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VIA KT133(*)
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LML33 starting to get annoying, Buz poor enough that I have up.
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Both 440BX boards were dual CPU versions.
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--
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Bernhard Praschinger later added:
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--
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AMD 751
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Buz perfect-tolerable
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AMD 760
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Buz perfect-tolerable
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--
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In general, people on the user mailinglist won't give you much of a chance
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if you have a VIA-based motherboard. They may be cheap, but sometimes, you'd
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rather want to spend some more money on better boards. In general, VIA
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mainboard's IDE/PCI performance will also suck badly compared to others.
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You'll noticed the DC10+/DC30+ aren't mentioned anywhere in the overview.
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Basically, you can assume that if the Buz works, the LML33 will work too. If
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the LML33 works, the DC10+/DC30+ will work too. They're most tolerant to
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different mainboard chipsets from all of the supported cards.
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If you experience timeouts during capture, buy a better mainboard or lower
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the quality/buffersize during capture (see 'Concerning buffer sizes, quality,
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output size etc.'). If it hangs, there's little we can do as of now. Check
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your IRQs and make sure the card has its own interrupts.
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===========================
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4. Programming interface
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This driver conforms to video4linux and video4linux2, both can be used to
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use the driver. Since video4linux didn't provide adequate calls to fully
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use the cards' features, we've introduced several programming extensions,
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which are currently officially accepted in the 2.4.x branch of the kernel.
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These extensions are known as the v4l/mjpeg extensions. See zoran.h for
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details (structs/ioctls).
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Information - video4linux:
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http://roadrunner.swansea.linux.org.uk/v4lapi.shtml
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Documentation/video4linux/API.html
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/usr/include/linux/videodev.h
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Information - video4linux/mjpeg extensions:
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./zoran.h
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(also see below)
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Information - video4linux2:
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http://www.thedirks.org/v4l2/
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/usr/include/linux/videodev2.h
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http://www.bytesex.org/v4l/
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More information on the video4linux/mjpeg extensions, by Serguei
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Miridonovi and Rainer Johanni:
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--
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The ioctls for that interface are as follows:
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BUZIOC_G_PARAMS
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BUZIOC_S_PARAMS
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Get and set the parameters of the buz. The user should always do a
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BUZIOC_G_PARAMS (with a struct buz_params) to obtain the default
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settings, change what he likes and then make a BUZIOC_S_PARAMS call.
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BUZIOC_REQBUFS
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Before being able to capture/playback, the user has to request
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the buffers he is wanting to use. Fill the structure
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zoran_requestbuffers with the size (recommended: 256*1024) and
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the number (recommended 32 up to 256). There are no such restrictions
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as for the Video for Linux buffers, you should LEAVE SUFFICIENT
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MEMORY for your system however, else strange things will happen ....
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On return, the zoran_requestbuffers structure contains number and
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size of the actually allocated buffers.
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You should use these numbers for doing a mmap of the buffers
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into the user space.
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The BUZIOC_REQBUFS ioctl also makes it happen, that the next mmap
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maps the MJPEG buffer instead of the V4L buffers.
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BUZIOC_QBUF_CAPT
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BUZIOC_QBUF_PLAY
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Queue a buffer for capture or playback. The first call also starts
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streaming capture. When streaming capture is going on, you may
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only queue further buffers or issue syncs until streaming
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capture is switched off again with a argument of -1 to
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a BUZIOC_QBUF_CAPT/BUZIOC_QBUF_PLAY ioctl.
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BUZIOC_SYNC
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Issue this ioctl when all buffers are queued. This ioctl will
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block until the first buffer becomes free for saving its
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data to disk (after BUZIOC_QBUF_CAPT) or for reuse (after BUZIOC_QBUF_PLAY).
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BUZIOC_G_STATUS
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Get the status of the input lines (video source connected/norm).
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For programming example, please, look at lavrec.c and lavplay.c code in
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lavtools-1.2p2 package (URL: http://www.cicese.mx/~mirsev/DC10plus/)
|
||
|
and the 'examples' directory in the original Buz driver distribution.
|
||
|
|
||
|
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. Remember that users now can lock the norm to
|
||
|
avoid any ambiguity.
|
||
|
--
|
||
|
Please note that lavplay/lavrec are also included in the MJPEG-tools
|
||
|
(http://mjpeg.sf.net/).
|
||
|
|
||
|
===========================
|
||
|
|
||
|
5. 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)
|
||
|
|
||
|
===========================
|
||
|
|
||
|
6. 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.
|
||
|
|
||
|
===========================
|
||
|
|
||
|
7. 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.
|
||
|
|
||
|
===========================
|
||
|
|
||
|
8. Maintainers/Contacting
|
||
|
|
||
|
The driver is currently maintained by Laurent Pinchart and Ronald Bultje
|
||
|
(<laurent.pinchart@skynet.be> and <rbultje@ronald.bitfreak.net>). For bug
|
||
|
reports or questions, please contact the mailinglist instead of the developers
|
||
|
individually. For user questions (i.e. bug reports or how-to questions), send
|
||
|
an email to <mjpeg-users@lists.sf.net>, for developers (i.e. if you want to
|
||
|
help programming), send an email to <mjpeg-developer@lists.sf.net>. See
|
||
|
http://www.sf.net/projects/mjpeg/ for subscription information.
|
||
|
|
||
|
For bug reports, be sure to include all the information as described in
|
||
|
the section 'It hangs/crashes/fails/whatevers! Help!'. Please make sure
|
||
|
you're using the latest version (http://mjpeg.sf.net/driver-zoran/).
|
||
|
|
||
|
Previous maintainers/developers of this driver include Serguei Miridonov
|
||
|
<mirsev@cicese.mx>, Wolfgang Scherr <scherr@net4you.net>, Dave Perks
|
||
|
<dperks@ibm.net> and Rainer Johanni <Rainer@Johanni.de>.
|
||
|
|
||
|
===========================
|
||
|
|
||
|
9. 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.
|
||
|
|
||
|
You should have received a copy of the GNU General Public License
|
||
|
along with this program; if not, write to the Free Software
|
||
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
||
|
|
||
|
See http://www.gnu.org/ for more information.
|