Multi-camera systems

In this article, we present some simple and effective techniques for accurately calibrating a multi-camera acquisition system. The proposed methods were proven to be capable of accurate results even when using very simple calibration target sets and low-cost imaging devices, such as standard TV-resolution cameras connected to commercial frame-grabbers. In fact, the performance of our calibration approach yielded results that were about the same as that of other traditional calibration methods based on large 3D target sets. The proposed calibration strategy is based on a multi-view multi-camera approach. This was based on the analysis of a number of views of a simple calibration target-set placed in different (unknown) positions. Furthermore, the method is based on a self-calibration approach, which can refine the a priori knowledge of the world coordinates of the targets (even when such information is very poor) while estimating the parameters of the camera model. Finally we proposed a method, to make the calibration technique adaptive through the analysis of natural scene features, allowing the camera parameters to hold accurate throughout the acquisition session in the presence of parameter drift.