A research and development project in Silicon Valley focused on solving screen projector keystoning -- the trapezoidal distortion that occurs when a projector is not perfectly perpendicular to the projection surface.

The Approach

Working alongside a project manager and a mathematician, I built an Android prototype that displayed calibration patterns and measured the device's tilt in degrees. The prototype projected a white screen in a darkened room, then captured photographs of the projection at various angles.

Image Analysis

Using Python and open-source computer graphics libraries, I analyzed each captured image to determine the exact pixel positions of the projected screen's corners. By evaluating how corner positions shifted across different projection angles, we were able to deduce a correction algorithm.

The Result

The final algorithm was elegantly simple from the user's perspective: align the projector at 90 degrees to the wall, and the keystoning correction applies automatically. No manual adjustment needed -- the system handled it based on the calibration data we had gathered and the mathematical model we derived.