C# Grab screenshot and OCR with Tesseract

This project is to create a library and test app that will grab a screenshot from any window and will return the OCR results. 1) Create a library (DLL) in C# (.net framework 4.0) that given a window handle and a rectangle will grab a screenshot at those relative co-ordinates. Bitmap Get_Screenshot(IntPtr handle, Rectangle rect) 2) Include a second library function that given the image from the screenshot will return the text using Tesseract OCR. String Get_Text(Bitmap image) 3) Create a function that given a window handle and a rectangle will return the text at those relative co-ordinates, using the two functions above. String Get_Window_Text(IntPtr handle, Rectangle rect) 4) Create a test app. In the app the user can click a button and then click a window to capture the window handle. The user can then draw a rectangle to specify where they want to capture text from. Then handle and co-ordinates should now be captured and displayed on the screen. The user can now click a button titled "Get text" to capture and display the window text. The app will use the library function "Get_Window_Text" created above to capture the text. This test app does not have to be very polished - it is purely to test the library function. To weed out candidates that don't read the description I am requesting that you include in your bid the name of the windows API function you will use to capture the screenshot or a link to a similar project you've worked on. That will let me know you've read this and aren't just bidding on anything you see. Thanks and can't wait to work with you!