A Minimal Solution for Sphere-Based Camera-Projector Pair Calibration

We propose a minimal solution for sphere-based camera-projector pair (CPP) calibration. Previous works often treated the camera and projector calibration as two independent problems, which exploit only intra-view information from geometric properties of sphere dual image formation and hence require at least three spheres for CPP calibration. However, other than intra-view information, we observe that inter-view information between camera and projector provides additional constraints. Combining these two kinds of information yields a minimal solution for CPP calibration, where only a single sphere is required. Extensive experiments have verified the effectiveness of proposed minimal solver, which demonstrates higher flexibility and comparable accuracy to the state-of-the-art methods. Moreover, the achieved flexibility allows high-quality 3D reconstruction with an uncalibrated CPP, given only a single sphere in the scene.