http://www.epicwar.com/ http://sc2.nibbits.com/maps/ Look at the two above websites. They each have a script or something, that, when someone uploads a map, the website automatically extracts the minimap image of the map. My knowledge of PHP and/or Javascript is not within the scope of that kind of programming, so I'm hoping some of you have the ability to do something like this. There are indeed map editor programs that can generate the minimap images by opening the editor program and clicking File >> Get Minimap Image or something among those lines. Perhaps making a PHP or Javascript code that can open a program and do the necessary steps is a method you would like to try. Please PM me if you are able to, one way or another, accomplish this and your estimated price.
I have to tools to do this, as well as the experience. I used to be heavily into wc3 modding =) Anyways, drop me a PM with your budget and such.