Batch Encode Video Files into FLV like YouTube

I am just curious, how does YouTube/google Video/ MySpace etc take a random avi video file and convert it into an FLV file?

I know it is a complicated process, but could somebody break it down for me?

 

I have a site like that on one of my servers.

To make is all work you will need Apache and:

FFmpeg (http://ffmpeg.mplayerhq.hu)
FFmpeg-PHP (http://ffmpeg-php.sourceforge.net)
Mplayer + Mencoder (http://www.mplayerhq.hu/design7/dload.html)
flv2tool (http://inlet-media.de/flvtool2)
Libogg + Libvorbis (http://www.xiph.org/downloads)
LAME MP3 Encoder (http://lame.sourceforge.net)

 

Edge, do you know of any tutorial that works? with proper support for sound? I have Debian Etch...

 

I think (it's some time ago) that you need to configure ffmpeg with mp3lame

Code:

./configure --enable-shared --enable-mp3lame
make
make install

I did write some personal notes on how I did it, but can not find it anymore :/