image recognition

I need working code that will allow for the capture and comparison of an x by y region of a window on a users screen i.e. I should be able to select an area of another window on screen and have the image in the selected area stored [to a file] and then reference that stored data to compare it to the window at another time and/or on multiple occasions. In essence this program will do one of two things: it will either provide a means for capturing an x by y area of another specified window and storing it OR, it will compare an x by y area of another specified window to a previously stored piece of a window. A user must be able to specify both the window and the specific co-ordinates to be captured by using the mouse to select the area or by providing start and end co-ordinates. All co-ordinates must be relative to the top left corner of the window to be captured from. The code must not grab a section of the screen but rather the relative part of a specified window, this is quite important to this project, if you attach a demo please demonstrate as to whether you can do this or not. The comparison must check for an exact match between the two selections - a window and area specified by co-ordinates and window and the previously stored data. The method of comparison is not important. If possible the comparison data should be stored in a compressed format to save space. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete documented source code of all work done. 2) Complete ownership and distribution copyrights to all work purchased. ## Platform win98+, visual basic 6.0