Here are some quick observations on trying to play Video files on Yellowdog (Note: I'm a Linux newbie and I've since installed Fedora 6.0 on my PS3 so I've lost a lot of the detail on what I actually did with Yellowdog. I'm probably going to reinstall Yellowdog this weekend so look out for updates)
The importance of YUM
I thought I'd start off by briefly mentioning that unlike a Microsoft OS, where you typically download and run a piece of software, on a Linux OS you may be required to download the "Source Code" for the software, build it on your particular flavour of Linux and then run it (assuming you can actually find out where it got installed ...) Bear in mind that you you may also need other software installed on your Linux OS before you can successfully build the software you actually want. Sometimes this can be as significant as needing an engine in your car before you can actually drive it anywhere. Fortunately, there is yet more software available for Linux OS's that help you download and manage these updates. YUM is an example of such software.
YUM comes pre-installed with Yellowdog, however, you'll have to modify the YUM.conf file to actually get YUM to work and this is not exactly straightforward for the uninitiated!
Yellowdog's Video Playing Software:
The Video player that comes installed with Yellowdog (I forget what it's called now) doesn't come pre-installed with DivX or Xvid codecs and I didn't make much progress in trying to build/install them.
Installing other Video Playing Software
I found that trying to install other, popular, Movie players like Zine (or is it Xine) or MPlayer a little challenging on Yellowdog. Firstly, I couldn't find any native binaries for these products so I had to download source and build it. I did manage to build and run the command line version of MPlayer, unfortunately the Graphical Interface for MPlayer wouldn't build on Yellowdog. I didn't get anywhere with Zine.
Playing local and remote movie files
In short SAMBA worked very well so I was able to detect and access a Windows XP share from my PS3 with no problems. Unfortunately, trying to get the default video playing software to actually play video files stored on my PC didn't work and I'm not sure why. Downloading the remote file onto the PS3 and playing it in MPlayer went fairly well at first. Unfortunately, when I tried resizing the video window, vertical Green lines started appearing on top of the video image.
As I mentioned at the beginning of the post, I'm really just starting out with Linux and I imagine using the PS3 as the host system doesn't make things easier. Future posts should have a little more detail than this one, but if there's anything specific you want to know, leave a comment and I'll see what I can do.