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Date:	Mon, 14 Aug 2000 15:25:23 -0700
To:	mailing.lists@quantum.cicese.mx
From:	mirsev@cicese.mx
Subject: Repost. Linux driver for DC10plus video capture card. V 0.4

Sorry, this is a repost. Previous message was sent with wrong version in the

August 14, 2000.

Linux driver for Miro/Pinnacle Systems Inc. DC10plus and some DC10 cards.
Release candidate.

  Homepage: http://www.cicese.mx/~mirsev/Linux/DC10plus

  This is a driver for DC10plus capture cards from Pinnacle Systems
  Inc. It also works with many old Miro DC10 cards with SAA7110A TV
  decoder and ADV7176 TV encoder (please, make sure that your card has
  these chips, otherwise the driver will not work).

  The driver is Video4Linux compliant and contains extensions to
  provide hardware support for full motion MJPEG compression and
  decompression. Since this driver is a derivative from the driver for
  Buz Iomega cards written by Dr. Rainer Johanni,
  http://www.johanni.de/munich-vision/buz/ they both have compatible
  API. I hope that this API will become a standard. At least, there is
  another driver, for LML33 cards, which shares the same API:

Formats supported by DC10plus driver:

  PAL/SECAM: up to 768x576 at 25 full frames per second;
  NTSC:      up to 640x480 at 30 full frames per second.

  The JPEG compression ratio is adjustable, so the data rate can be
  varied from 6-7 MBytes/s down to 1-2 MBytes/s depending on the
  required image quality.

Hardware compression

  Since the card provides hardware compression, even low end machines
  can be successfully used for movie capture and playback. I've tested
  the driver with 2.2.14 kernel running on 233 MHz Pentium MMX with 64M
  RAM on 430TX motherboard and with 10GB IDE drive from Western Digital

  On one test run I've got 0 frames dropped during about 20 minutes of
  full motion NTSC (I live in Mexico) video capture with fully
  synchronized audio. The command was

    lavrec -fa -in -d1 -l -1 -q30 -w /dos/g/capture/Linux/test%03d.avi

  for recording, and

    lavplay -n128 /dos/g/capture/Linux/test*.avi

  for playback. (See lavtools distribution for more information).

  Typical run of similar test can provide as few as 6-8 dropped frames per
  half of an hour. You mileage may vary, though.

Compilation and installation

  Please, read file README regarding compilation and installation
  issues. Note, that you will need mem=XXX setting in lilo.conf, or
  bigphysarea patch only if you are planning to use uncompressed motion
  or still capture using XawTV and other programs.

  If you use only MJPEG compressed capture provided by the driver, you
  should not need large memory areas for DMA. In this case, you will be
  able to capture and playback movies with lavtools, however you will
  not be able to use capture features of XawTV and other similar
  programs (you can still watch video on the screen).

Tested applications:

  XawTV         to watch video on your computer monitor.

  kwintv        the same (you might need to use option lock_norm=1, see
                the description in Changes section below).
  lavtools      To record and playback AVI or Quicktime files. Note: you
                will need patched version, lavtools-1.2p2 to support new
                features of this driver. Please visit driver homepage for
                more info.

  Broadcast2000 reportedly (I didn't try that) can accept movies
                recorded by lavrec for editing and then edited movie
                can be played back by lavplay program.

  MainActor 3.53 also can accept movies recorded by lavrec for editing.

Changes in v0.4:

1. Now the driver (with new lavtools-1.2p2) is able to deal with cropped
   TV clips produced by miro/Pinnacle software. Try new lavplay on clips
   which you couldn't play before.

2. For software developers: now 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 you can lock the
   norm (see item 3 below) to avoid any ambiguity.

3. Two new parameters have been added for the driver configuration on

   lock_norm=1 will disable TV standard switching but will not
               produce any error response to the application
               trying to change norm.
   lock_norm=2 will disable changing TV standard but it will
               also return error to the application attempting
               to switch norm. It can be useful with applications
               like XawTV which switch norm at the beginning
               to find out which TV standards are available.
   This feature can be useful in combination with default_norm
   parameter to lock the norm for current country and prevent
   it from switching by some not well behaving programs. Default
   is 0, i.e. switching is enabled, however I would recommend
   to always lock the norm unless you are dealing with
   different TV standards.

   pass_through=0 will enable TV output only when the device is
                  in use by some program. Otherwise, the TV
                  monitor will show a standard color bar.
   pass_through=1 will enable passing of input TV signal to the
                  Default is 0.

4. Interrupt processing code was modified to make the driver working
   even after codec crash. It should greatly improve the driver
   reliability. I've tested switching channels on the VCR which was
   used as video signal source during recording with lavrec, and the
   driver survived the switch and other glitches in the signal,
   restarting and continuing capture. Some frames in the clip were
   corrupted but they can be cut by video editing software. The driver
   also survives corrupted frames during playback.

5. The driver now is able to play MJPEG files on the computer monitor
   screen simultaneously with playing on the attached TV monitor. However,
   there is only one utility which can provide such functionality:
   mplay_screen from examples directory of buz-1.0.1 driver distribution.
   It plays files in its own format which must be recorded by mrecord from
   the same distribution. This is a proprietary format, incompatible with
   AVI format. Nevertheless, now the driver is almost ready for
   applications which will play AVI files on the computer screen.
   Please, see item 7 below for other experimental feature.

6. SECAM support. The driver now provides partial support for SECAM TV
   standard used in Russia and some other countries from former Soviet
   Union. Probably, this standard is also used in France but I'm not
   sure of this. The partial (not full) support means that the driver
   can accept color SECAM signal for capture, so users from these
   countries can record clips and watch video on the computer monitor
   screen using XawTV or similar application in full color, but the
   image on the attached TV monitor during the capture can be B&W or
   with messed up colors. Note, however, that this will be only during
   capture. The playback of the captured clip will be in PAL standard
   and with full color! So, now users from Russia and other countries
   with SECAM standard can watch TV programs and capture clips from
   broadcast channels. Of course, since DC10plus does not have built-in
   tuner, you will need to take the signal from your VCR, TV or other
   source with external tuner.

7. Now the driver can to be used by two programs at the same time
   (please, see warning note below regarding this feature). Using XawTV
   you can watch what you are recording or playing back with lavtools.
   I've tested the following sequence and it worked for me:

   * start xawtv and switch inputs, TV standards, and adjust video
     (contrast, saturation, etc.). You may also run your favorite
     audio mixer application to adjust audio inputs.

   * run lavrec with options: 

       -i<set your input and norm here> (to choose proper input
                                         and TV standard)
       -l -1  (to use audio mixer settings)

       Other lavrec option can be added at your choice.

   * watch the movie in xawtv window while recording it as AVI or
     Quicktime file.

   * when recording is finished, run lavplay or xlav and watch your
     clip in xawtv window.

   * Note: you should not quit xawtv during recording or playing back.
     If you quit xawtv during recording or playback, another lavtools
     program will stop and may even crash.

   I'm not sure that the same will work for you. You can try but,
   please, be careful.

   WARNING! This is an experimental feature and I'm not sure if it will
   be supported in the future. The driver was not designed to be used
   like this and it has no protection against any interference between

8. /proc/buz0 entry: using 'cat /proc/buz0' you can see the contents of
   ZR36057/67 chip registers. It is also possible to modify the
   contents of some registers directly. WARNING: modified contents is
   not stored in the driver memory, if you restart any program which
   uses this driver or even change position or cause redraw of a window
   of xawtv or other program, the original registers contents will be
   restored by the driver. However, it can be used to change ZR36067
   registers on the fly for fine tuning and then to include these
   changes into driver code. This feature is very limited and still
   requires some documentation. However, if you are impatient, look at
   buz_procfs.c code and (IMPORTANT!) read ZR36057/67 manual. To set
   TopField bit, for example, you need to type as root:
   echo TopField=1 > /proc/buz0
   If you use this feature and have found some interesting result, please, let
   me know.

I've tested the driver with 2.2.14 kernel. There is still no support
for new i2c subsystem from newer kernels. If someone wants to add it,
please do. I will appreciate that.

Please, try the driver, and let me know if something is wrong. It would
be nice if you fix something and send me a patch.

To download the driver and for other news and updates, please, visit


Good luck.

Serguei Miridonov

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