How do I make normal maps from images?

Game Engine Game Engine Support and Discussion
1

I need them for my game and the tutorials on other websites only show a way of making normal maps out of high poly objects.

Thanks.

2

One way is to use the Normal Map plug-in for Gimp to make a normal map from an image.
Here’s a short tutorial on how to use it with Valve’s Source engine.
http://developer.valvesoftware.com/wiki/Normal_Map_Creation_in_The_GIMP