Euclidean Auto Calibration of Camera Networks: Baseline Constraint Removes Scale Ambiguity
This addresses the scale preservation issue in applications like multi-party telepresence, where fusing multiple 3D scenes requires accurate scale, representing an incremental improvement over prior methods.
The paper tackles the problem of metric auto calibration in camera networks, which recovers shape but not scale, by introducing a stereo pair with known baseline to remove scale ambiguity. The method achieves Euclidean auto calibration, experimentally validated on a four-camera network, and shows favorable shape recovery compared to existing methods like Zhang and Pollefeys.
Metric auto calibration of a camera network from multiple views has been reported by several authors. Resulting 3D reconstruction recovers shape faithfully, but not scale. However, preservation of scale becomes critical in applications, such as multi-party telepresence, where multiple 3D scenes need to be fused into a single coordinate system. In this context, we propose a camera network configuration that includes a stereo pair with known baseline separation, and analytically demonstrate Euclidean auto calibration of such network under mild conditions. Further, we experimentally validate our theory using a four-camera network. Importantly, our method not only recovers scale, but also compares favorably with the well known Zhang and Pollefeys methods in terms of shape recovery.