如何在服务器上生成Flash swf的屏幕截图？

I'm writing a flash app using the open source tools. I would like to load a data file in to the app and capture a screenshot of the stage on the server. The only part that seems mysterious is running the app on the server. In fact, I don't even care if it's the same app running on the server and in the browser--if I can use the flash stage and drawing routines to produce an image server-side, I'm happy. If I have to delve in to flex, fine. Right now I'm having problems finding any starting point at all.I'm writing a flash app using the open source t