Playing DVDs on Linux/PPC

Introduction

Overall I'm happy that I got it to work at all. In practice, the playback quality is not good enough to save me from booting into Mac OS to play a DVD in most cases. However, there is definite hope that the quality will improve.

I'd also like to thank Guillarume Laures for his very helpful description of how he got DVDs working on his LinuxPPC box. Much of the material in this page duplicates his procedure, but I also include instructions to decode encrypted DVDs.

I hope this procedure is useful to you, but of course there is no guarantee that it will work for you, and I probably won't have time to help you debug your setup. For that, send a message to one of the mailing lists or newsgroups. However, I do of course welcome comments and suggestions!

Problems

• Poor audio and/or video quality. You mileage may vary on this, depending on the speed of your system (mine is 350 MHz) and how much you play around with options to the video and audio players. On my 350 MHz G4, I got about 5-10 fps, and slightly jumpy audio.
• Requires a large amount of free disk space to play a DVD -- about 1-2 GB. This is something that should be relatively easy to fix, and should improve playback quality significantly. (See below.)

System requirements

• Power Mac running Linux/PPC with DVD-ROM drive
• Several gigabytes of free disk space (for temporary use while playing DVDs)

Procedure

1. Get a kernel with DVD support. To see if your kernel supports DVD drives, run this in a shell:

   dmesg | grep DVD

   If the output looks something like this, then your kernel supports DVDs:

   hdc: HITACHI DVD-ROM GD-3000, ATAPI CD/DVD-ROM drive
   hdc: ATAPI 32X DVD-ROM drive, 512kB Cache, DMA

   If the output looks something like this, then your kernel does not support DVDs:

   hdc: HITACHI DVD-ROM GD-3000, ATAPI CD-ROM drive

   The 2.4.x kernels should all recognize your DVD drive. I think that some of the older kernels, maybe 2.2.17 and above, have DVD support as well. I personally was running 2.2.15pre19 which doesn't have DVD support, and upgraded to 2.4.2pre3 which does have DVD support. I followed this entire procedure using a 2.4.2pre3 kernel.

   Here's how to recompile your kernel.

2. Install libcss.
   1. Download from LiViD's web site: libcss-0.1.0.tar.gz (143 KB)
   2. Unpack the archive:

      gunzip libcss-0.1.0.tar.gz
      tar -xf libcss-0.1.0.tar
      cd libcss-0.1.0

   3. When I first compiled it, libcss didn't work for me (specifically, the program tstdvd didn't work). I had to make the following change: in the file src/tstdvd.c, line 57 is:

      #define FIBMAP 1

      replace this with:

      #define FIBMAP ((1 << 29) + 1)

   4. Configure libcss:

      ./configure

      Note: If you get compile errors, your kernel includes might not be in the right place. When I upgraded my kernel, I didn't install the new kernel headers (silly me). If you didn't do that either, or if your kernel headers are anywhere other than /usr/include/linux/, you will have to do this:

      ./configure --with-kernel-includes=PATH_TO_KERNEL_INCLUDES

      If you built your kernel in KERNEL_BUILD_DIR, then your PATH_TO_KERNEL_INCLUDES probably is KERNEL_BUILD_DIR/include.
   5. Build and install libcss:

      make
      su -c "make install"
      

3. Install ac3dec, the audio decoder. I used binaries from Guillarume Laures. Note that although that file ends in .tgz, it's actually a tar archive:

   tar -xf linuxppc_dvd_bin-20-08-00.tgz
   cd linuxppc_dvd_bin-20-08-00
   su -c "cp ac3dec /usr/local/bin"
   

   You could also download the source and build your own ac3dec, but I believe the binary above is the latest version.
4. Install DVDView. A dvdview binary is also included in the tar archive you downloaded to get the binary of ac3dec. All you need to do is install it:

   su -c "cp dvdview /usr/local/bin"
   

   However, that is not the latest version of DVDview. Instead of using the binary, I downloaded the source (dvdview1.1.0.tar.gz, 242 K) and installed it:

   gunzip dvdview1.1.0.tar.gz
   tar -xf dvdview1.1.0.tar
   cd ulib
   ./configure
   make
   cd ../dvdview
   ./configure
   cd src
   make
   su -c "cp dvdview /usr/local/bin"
   

5. Play some DVDs! You now have all the necessary pieces installed to decode encrypted DVDs and play them with both video and audio. I wrote a little Perl script to execute all the necessary commands and play the DVD.
   1. Download it
   2. un-tarball it: gunzip dvdplay.tar.gz; tar -xf dvdplay.tar
   3. Make it executable: chmod +x dvdplay.pl
   4. Check over the parameters at the top of the script. Change anything that needs to be changed. In particular:
      • $CSS_CAT needs to be the path to css_cat, which is in the src directory in the directory where you compiled libcss.
      • $TMP_DIR has to be a directory with lots of free space -- probably about 1-2 GB. It needs to be able to store the largest DVD clip that you will play. (Each movie is split up into several clips.) The reason is the following: unfortunately, DVDView does not accept input from stdin, so this leaves us in a very suboptimal situation: we have to unencrypt the data and write it to disk with css_cat, at the same time that we are reading it and playing it with dvdview. The result is a big performance hit and the requirement for lots of free disk space.
   5. Put a DVD in your drive (don't mount it!)
   6. Run the script as root:

      su
      ./dvdplay.pl
      

      To skip to the next clip, press control-C. To kill the whole thing, press control-C twice.

Alternative software

• mpeg2dec seems to provide much better video quality, but unfortunately doesn't do audio.
• OMS is a Linux DVD player, but I couldn't get it to compile and work. Perhaps you will have more luck if you are more persistent. :-)
• Xine doesn't yet support PPC Linux.
• VideoLan compiles and runs with better video quality than DVDView, and it theoretically does audio decoding as well -- but I couldn't get audio to work. I think this may be a platform-specific issue (endianness?) in DVDView's ac3 decoder. (Note that ac3dec works fine on PPC Linux.) I tried version 0.2.62 of VideoLan.
• MPlayer doesn't support PPC Linux.