Automatic keystone correction using a single camera

In this paper, we introduce an algorithm for removing keystone distortion, which frequently occurs when the projector is not precisely aligned to the screen, For this purpose, we generate a pre-warp image from the transformation between the projector and the screen using a single camera while automatically computing homography from the pattern and screen images and determining a scaled rigid body transform. Thus our method is useful for multi-projector-based applications.