Have your application startup and resize the browser window to full screen. Include a screen capture application, trigger it, and save the screen capture bitmap. Take the image file, suitably process it, and determine the feature of interest. Suitably calculate the image size. Do the necessary calculations for your application, apply the binary patch to your application code, resize the browser window, shut down IE, reboot, restart IE, reload your application, and you're done.

See - no problem. And no free software required.

Cheers,
Scott.