DVD Playing HOWTO
  Nathan Rowlan, nkr@helo.org
  v0.1.8 5 June 2000

  A (hopefully) easy to follow explanation on how to get DVD movie play�
  back in Linux.
  ______________________________________________________________________

  Table of Contents


  1. Introduction

     1.1 Goal
     1.2 New Versions
     1.3 Copyrights and Trademarks
     1.4 Thanks
     1.5 Translations

  2. Requirements

  3. Files

  4. Installation

     4.1 Kernel
     4.2 LiViD Utilities

  5. Playing

  6. Additional Stuff

     6.1 Setting up MTRR's

  7. Problems

     7.1 Run time errors
        7.1.1 Illegal Instruction Error
     7.2 Compilation errors
        7.2.1 `dvd_struct' undeclared...
        7.2.2 can't determine absolute dir of '../../../../src/plugin/codec/mpeg2dec/.libs'
     7.3 Broken stuff
     7.4 Other errors

  8. To Do



  ______________________________________________________________________

  1.  Introduction

  1.1.  Goal

  The purpose of this is to provide step by step instructions on getting
  DVD movies to play in Linux. I will try to be as clear as possible,
  but if something is confusing or incorrect, please tell me about it
  and I'll fix it. If you have any questions, you can subscribe to the
  livid-dev mailing list by sending a blank email to livid-dev-
  subscribe@linuxvideo.org.

  1.2.  New Versions

  This howto is available in many formats, including html and tex. The
  newest version can always be retrieved from my site at
  http://helo.org/dvd/howto/ <http://helo.org/dvd/howto/>. It is highly
  recommended that you get the most recent version, as  this howto is
  being updated quite often.

  1.3.  Copyrights and Trademarks

  This manual may be reproduced in whole or in part, without fee,
  subject to the following restrictions:


  �  The copyright notice above and this permission notice must be
     preserved complete on all complete or partial copies.

  �  Any translation or derived work must be approved by the author in
     writing before distribution.

  �  If you distribute this work in part, instructions for obtaining the
     complete version of this manual must be included, and a means for
     obtaining a complete version provided.

  �  Small portions may be reproduced as illustrations for reviews or
     quotes in other works without this permission notice if proper
     citation is given.

  Exceptions to these rules may be granted for acedemic purposes: Write
  to the author and ask. These restrictions are here to protect us as
  authors, not to restrict you as learners and educators. Any souce code
  (aside from the SGML this document was written in) in this document is
  placed under the GNU General Public License, available via anonymous
  FTP from the GNU archive <ftp://ftp.gnu.org/GNU/COPYING>.

  1.4.  Thanks

  Thanks to the authors of oms and the rest of the LiViD developers, who
  have given the project much of their time and work, and also to those
  individuals who have given me feedback to make this HOWTO better.

  Much of the layout of this HOWTO was gotten from the HOWTO-HOWTO,
  written by Mark F. Komarinski.  It can be found at
  http://www.linuxdoc.org/ <http://www.linuxdoc.org/>.

  1.5.  Translations

  Any translations of this document that I recieve go into
  http://helo.org/dvd/howto/trans/ <http://helo.org/dvd/howto/trans/>.
  If you would like to translate this howto, please email me at
  nkr@helo.org.

  2.  Requirements


  This HOWTO assumes you have:

  �  Linux > v2.2.0

  �  XFree86 3.3.X

  �  A DVD-ROM/RAM/RW drive supported in Linux (most are)

  �  A decent knowledge of bash and english

  �  A master's degree in Nuclear Engineering



  3.  Files

  First things first, you need to get a kernel with MTRR (more on this
  later) and DVD ioctl support. While MTRR's have been in the kernel
  since 2.2.11 (correct me if I'm wrong), you will probably need to
  update your kernel to get DVD ioctls.  There are two ways to skin this
  cat, you can either download a development kernel (v2.3.x), or patch a
  stable release kernel (v2.2.x), the patches are at
  http://www.kernel.dk/ <http://www.kernel.dk/>, and the kernel can be
  found on your favorite mirror of ftp://ftp.kernel.org/
  <ftp://ftp.kernel.org>.

  Next, you need to get the LiViD utilities. This can be done two ways:


  �  Get the LiViD utilities from CVS, so you can update it as it is
     being updated by the developers. (recommended)



         The following commands will retrieve them:

         # mkdir ~/livid
         # cd ~/livid
         # export CVSROOT=:pserver:anonymous@cvs.linuxvideo.org:/cvs/livid
         # cvs login
         (Logging in to anonymous@cvs.linuxvideo.org)
         CVS password:

         There is no password for anonymous, just press enter.

         # cvs -z3 co -P ac3dec oms mpeg2dec mgadvd

         They should download into their respective directories.



  �   If you don't like CVS (freak!), you can download the most recent
     nightly tarball of LiViD. This contains more than you need, but if
     you are really afraid of using CVS for some reason, suit yourself.


         It can be found at:

         http://linuxvideo.org/developer/data/livid.tar.gz



  4.  Installation

  4.1.  Kernel

  If you have a development kernel (2.3.x), you should already have DVD
  ioctl support, so you just need to make sure you have MTRR support
  enabled in the kernel configuration, and then compile and install it
  as you normally would.


  If you want to patch your exisiting kernel, start by going to


          http://www.kernel.dk/


  and downloading the correct patch for your kernel.


  If don't know how to install or patch your kernel, you should go read
  the Kernel HOWTO at:


          http://howto.tucows.com/LDP/HOWTO/Kernel-HOWTO.html



  4.2.  LiViD Utilities

  To install the LiViD utilities, you need to make sure you have
  /usr/local/lib somewhere in /etc/ld.so.conf.

  The following commands should compile and install the LiViD utilities
  on your system.  If you have problems, please see the "Problems"
  section.



        ac3dec:

          # cd ~/livid/ac3dec
          # ./autogen.sh
          # make
          # make install

        mpeg2dec:

          # cd ~/livid/mpeg2dec
          # ./autogen.sh
          # make
          # make install

        oms:

          # cd ~/livid/oms
          # ./autogen.sh
          # ./configure
          # make
          # make install



  Now the necessary LiViD utilities should be installed.  oms needs some
  special fifo pipes to be created for the DVD data to travel over.
  These can be made with the following commands (if they don't already
  exist):



          # mkfifo /tmp/video
          # mkfifo /tmp/audio



  One last thing to do. Oms needs /dev/dvd to be a symlink to where your
  DVD drive resides, such as /dev/hdb1 or /dev/scd0.  If it is at
  /dev/cdrom, you would create the link by typing:


          # ln -s /dev/cdrom /dev/dvd

  It is generally a good idea not to make a symlink to a symlink,
  because it adds unnecessary I/O.  Replace /dev/cdrom with the correct
  device that your dvd drive is on.

  5.  Playing


  To play a DVD, you need to be running X in 16-bit color mode. With the
  DVD in the drive, type:



          # ac3dec /tmp/audio& mpeg2dec /tmp/video& oms



  If all has gone well, some text should fly by, followed by it asking
  you if you want it to look up the name of the disk in the DVDDB.  It
  is safe to say yes. Then, the oms panel should pop up. Click the play
  button and the video window should appear and begin playing.

  6.  Additional Stuff

  6.1.  Setting up MTRR's



                  ** Note to Matrox video card owners **

                  If you have matroxfb compiled into the kernel,
                  chances are that your MTRR's are already set
                  up.  You can probably just skip this section.



  Setting up your MTRR's can increase video performance quite a bit in
  some cases, so it is a good idea to do it.  First, you need to make
  sure you have MTRR support in your kernel by typing:



             # ls /proc/mtrr



  If it tells you that there is no such thing as /proc/mtrr, you need to
  recompile your kernel with MTRR support (it is under "Processor type
  and features" in menuconfig).


  Once you know MTRR is working, you need to know the base memory
  address of your video card, and how much video ram it has.  The
  easiest way to do this is to look at the output of X as it starts up.
  Because the output usually scrolls off the screen and is lost when it
  switches to a different tty, you need to redirect the output of X to a
  file (xoutput) so you can go back and look at it to get the needed
  values.  This can be done by typing:



             # startx 2> xoutput



  The line having the needed information is probably somewhere towards
  the middle of xoutput, and should look something like:



             (--) SVGA: PCI: NVidia Riva TNT2 rev 17, Memory @ 0xee000000, 0xe2000000



  Once you have located that, write down the last memory address, in
  this case 0xe2000000.  Depending on your hardware, you may or may not
  have multiple memory addresses shown, so don't worry if yours looks a
  little different. With this information recorded, you can delete
  xoutput.


  Next you need to create a new MTRR. In order to do that, you have know
  how much ram your video card has in hex. Here are some common values:



             4MB  -- 0x400000
             8MB  -- 0x800000
             16MB -- 0x1000000
             32MB -- 0x2000000



  To add the MTRR, type:



             # echo "base=0xe2000000 size=0x2000000 type=write-combining" >| /proc/mtrr



  Substituting "0xe2000000" and "0x2000000" with the base address and
  amount of video ram specific to your system.


  Now you should have MTRR set up, and just to make sure, type:



             # cat /proc/mtrr



  And you should get output that looks remotely similar to:



             reg00: base=0x00000000 (   0MB), size= 128MB: write-back, count=1
             reg01: base=0xe2000000 (3616MB), size=  32MB: write-combining, count=1



  Again, the number of entries will probably be different from these,
  don't sweat it.


  7.  Problems

  7.1.  Run time errors

  This is a (small) list of known run-time errors.

  7.1.1.  Illegal Instruction Error

  If you use a non-Intel chip (K6 especially), and you are getting this
  error when you try to run mpeg2video, try editing nist/configure.in,
  lines 129 and 130:



                 CFLAGS="$CFLAGS -DHAVE_MMX -DLINUX -march=i686 -fschedule-insns2 -malign-doub
                 CXXFLAGS="$CXXFLAGS -DHAVE_MMX -DLINUX -march=i686 -fschedule-insns2 -malign-



  replace "-march=i686" in both with "-march=i586", and then recompile
  and reinstall.

  7.2.  Compilation errors

  This is a running list of common compilation errors that have known
  fixes.

  7.2.1.  `dvd_struct' undeclared...

  The most frequent problem people have when trying to compile these
  utilities stems from oms looking in the wrong place for the kernel
  headers. By default, it uses /usr/include/[linux|asm], but those
  headers are from a stable kernel so that when you compile a normal
  program, it will be using stable headers. oms needs to use non-stable
  (or patched) kernel headers, so when oms tries to compile, many things
  are undeclared and compilation fails. The best way to fix this is to
  edit the oms Makefile and -I/usr/src/linux/include to the CFLAGS and
  CXXFLAGS. (thanks to Adam Powell for this info)


          These commands should do it:

          # mkdir /usr/include/old
          # mv /usr/include/linux /usr/include/old/linux
          # mv /usr/include/asm /usr/include/old/asm
          # mv /usr/include/scsi /usr/include/old/scsi
          # ln -s /usr/src/linux/include/linux /usr/include/linux
          # ln -s /usr/src/linux/include/scsi /usr/include/scsi
          # ln -s /usr/src/linux/include/asm /usr/include/asm



  7.2.2.  can't determine absolute dir of '../../../../src/plu�
  gin/codec/mpeg2dec/.libs'

  Another common error is with the oms/src/plugin/codec/mpeg2dec/.libs
  directory. For some reason or another, this directory does not exist,
  and it needs to for compilation. To fix it, just make the directory:


          # mkdir src/plugin/codec/mpeg2dec/.libs



  7.3.  Broken stuff

  Features that don't currently work as intended:

  �  None of the chapter seek buttons work very well (crash).

  �  Once stopped, it doesn't like to start again (crash).

  �  Audio/video like to skip every second or so.

  �  Extreme slowdowns at beginning of chapters with mpeg2dec.

  �  Sometimes ac3dec doesn't close properly, and must be killed via
     "killall ac3dec".

  7.4.  Other errors

  If your problem isn't listed here, then likely the current CVS code
  has a bug in it. The best thing to do is just to wait a few days, and
  then try updating from CVS. There is a mailing list where you can ask
  questions, to subscribe send a blank email to livid-dev-
  subscribe@linuxvideo.org.

  8.  To Do


  �  Get someone with a Matrox card to send me a list of things they did
     to improve performance. (dent!!!)

  �  Makefile options (HAVE_MMX, HAVE_3Dnow, etc)

  �  -march=k6 for mpeg2dec

  �  add easy MTRR stuff (framebuffer)

  �  add need for region coding to be set on most drives:
     www.linuxtv.org/dvd