I need to develop a program that can identify a known rectangle image/pattern being displayed on the screen in a fixed location. I also need this program to identify text being displayed on the screen in a fixed location.

There are about seventy-five (75) such images. I know what they all look like, and can create a pool of bitmap images to match against, or other similar method so the program has something to match against.

I know such a program is possible, I've seen others that perform this very ability. Unfortunately the program displaying these images/patterns and text that I need to identify has no API to interface with it, and is a Windows application. I think what I'm trying to do is called screen scraping, but unfortunately all I have been able to find on screen scraping is either for getting information from websites or text terminals.

If anyone could give me some leads on how to start on this, I would greatly appreciate it. I'm not sure if I need to have the program grab a full screen screenshot and start analyzing that, or if it's possible to have the program grab a screenshot of the specific window that's open (like ALT+PRINTSCREEN) so it can read the information even if the target window is being hidden or minimized.

I have a lot of programming experience, but none of it is with Windows graphical applications. I'm not sure how to get such screenshots, and once I have that, how to search for a known image/pattern within the screenshot.

I don't mind doing this in C++ or C#. Using the .NET framework is fine.