Per-pixel camera calibration for 3D range scanning

Structured-light rangefinder is distinguished from other range scanning systems by its use of off-the-shelf hardware and fast data acquisition. We propose a novel approach to calibrate such a system, namely, calibrate the camera and the projector of the system. This approach handles all types of distortions and produces results in high accuracy. Basically, camera calibration techniques compute the pixel-ray correspondences and represent them by a mathematic model with limited number of parameters. These parametric models, however, cannot model general distortions while distortions not modelled, sometimes, can greatly affect the quality of further applications. The proposed approach computes and maintains a ray database for all pixels explicitly. By trading memory for accuracy, this approach solves the above problem. The resulting ray database can be directly used for 3D point reconstruction using calibration system. It is also useful for model fitting and other operations.