Image manipulation

Hi,

I'm a beginner who's trying to use Squeak to do some image
manipulation at the back end. It's part of a Webapp for
medical images (the Web part might be handled by Seaside). I really
like Seaside, but I have not decided because I'm concerned about
image manipulation in Squeak. So here's the issue:

1. I have not found a squeak package that does something
similar to ImageMagick. If there's no such facility in Squeak,
how can I "call" an external library such as ImageMagick
from the Squeak image?

2. If there is something equivalent, I'm still concerned about
the performance (the Webapp will be heavily used).

Could anyone give me some advice on this matter? Thanks
a lot for your help.

G.M.