I keep losing those snazzy screen grab icons

[Dave M G]

Ubuntu Users,

Up until recently, whenever I had an AVI or MPG or any kind of video 
file on my desktop, the icon for that file would be a screen grab from 
within that video.

However, recently I did a clean up of the video and audio programs I had 
on disk. After experimenting around, I've decided that Amarok handles 
all my audio needs, and Xine handles all my video needs. I never used 
programs like XMMS or Totem. I had almost a dozen others that I tried 
out but decided against.

So I used Synaptic to remove them. I must have lost a dependancy or 
something, because now video files don't have those snazzy screen grab 
icons, they just all have the same document icon with the letters "AVI" 
or "MPEG" on them.

This is a minor issue, but those attractive screen grab icons made me 
happy. So I'd like to get them back.

Actually, when I first installed Ubuntu, it didn't default to having 
these snazzy icons. If I recall correctly, the solution was to have 
Gstreamer installed. So I've made sure that I do, but I don't have my 
icons back.

I'd like to get the screen grab icons back without having to install 
video player applications that I don't use, if possible. But, if it's 
absolutely necessary, I guess I will.

Does anyone know what package or library module is responsible for 
displaying video file icons as images from the video?

--
Dave M G