I can't play the video files back / I don't see the video when I play the file, I just hear the audio! (Linux)
These files should play back fine with any recent version of Xine or mplayer, which are available in all modern distros. Some distros do not include MP3 playback support "out-of-the-box" for legal reasons. This includes Fedora Core, OpenSUSE and Ubuntu. If you have not already done so you'll need to install an MP3 codec, such as lame. For Fedora Core, please follow these instructions to install them. lame is included in the multiverse repository on Ubuntu, which isn't enabled by default. The Totem media player as shipped in Fedora Core and Ubuntu doesn't seem to play anything, so you should use totem-xine instead.
If you have problems playing these files, please raise it on the MailingList, giving details of the Linux distribution you are using and the versions of media player(s) you have tried.
I can't play the video files back (Windows)
Many Windows systems will be able to play back these files without any additional software being installed as they will already have a compatible codec installed. If not you will have to install VLC media player, [[DivX player]], ffdshow or another media player with the necessary codec. ffdshow is recommended as this acts a a plugin to Windows Media player, enabling it to play files encoded with many MPEG4 codecs.
How did you choose the codecs that you use for the video files?
Xvid is an open source video codec that can be played back by FLOSS media players, like mplayer, xine and totem. It does not require access to Windows codecs to work. It can playback on Windows using the !DivX codec or ffdshow under Windows Media Player, Winamp and !DivX player. It provides compression of a good enough quality for us to produce reasonably sized files.
So why MP3 for the audio in the video files?
We wanted to use a format that was as cross-platform as possible. The MP3 format is supported by FLOSS media players, despite potential patent issues. It does not require access to Windows codecs to work. It is also supported by Windows Media Player, Winamp and !DivX player. The most obvious alternative un-restricted codec is Vorbis but this is sadly not well supported by Windows players, even with additional plugins. (This situation has since changed with the release of a Vorbis codec for Windows Media Player.)
Why did you stop using the XVid / MP3 combination?
We had feedback from LUG members who had had issues playing the videos back. The main issue was the lack of MP3 support on the major distros. Although this was documented in this FAQ, some people needed help to install MP3 codecs. Some members were concerned that Windows users were unable to watch the videos because they didn't have an MPEG4 codec installed and were unable to install extra software on their system. This was felt to prevent the promotion of FLOSS to Windows users, who may be eager to find out more but work in a locked-down Windows environment. At the end of the day, although the format worked for the vast majority of people, it didn't play "out-of-the-box" on the major Linux distros nor Windows, so it wasn't really very satisfactory.