Software-Based Non-invasive Geometric Correction of Projector

Curved screens are often used in virtual reality vision systems. But distortion happens when projecting on a curved surface. Some special projectors and equipment have been invented to solve this problem. Instead of using such expensive hardware equipment, we propose a software-based non-invasive geometric correction method in this paper, which can rectify the distorted image projected on any curved screen interactively without modifying source code. For applications based on OpenGL, we make a new opengl32.dll to intercept the OpenGL API functions (especially SwapBuffer) in Windows operating system´s library search path. And most of our rectification was implemented in the function we wrote to substitute the original SwapBuffer. Considering different demands from different users, we leaved the picture quality and the response time of the system controllable.