Perceptual radiometric compensation for inter-reflection in immersive projection environment

We present a fast perceptual radiometric compensation method for inter-reflection in immersive projection environment. Radiometric compensation is the inverse process of light transport. As light transport process can be described by a matrix-vector multiplication equation, radiometric compensation for inter-reflection can be achieved by solving the equation to get the vector, during which matrix inversion should be computed. As the dimensions of the matrix are equivalent to the resolution of images, such matrix inversion is both time and storage consuming. Unlike previous methods, our method adopts projector-camera system to simulate the inversion, and treats the compensation as a non-linear optimization problem which is formulated from full light transport matrix and non-linear color space conversion. To make physical multiplication simulation more practical, the method adjusts the range of projector-camera system adaptively and reduces the high-frequency errors caused by clipping error and measured error to make the compensated results smoother. We implement an immersive projection display prototype. The experiments show that our method achieves better results compared with the previous method.