An Assignment Scheme to Control Multiple Pan/Tilt Cameras for 3D Video

Abstract

This paper presents an assignment scheme to control multiple Pan/Tilt (PT) cameras for 3D video of a moving object. The system combines static wide field of view (FOV) cameras and active Pan/Tilt (PT) cameras with narrow FOV within a networked platform. We consider the general case where the active cameras have as high resolution as they can capture only partial views of the object. The major issue is the automatic assignment of each active camera to an appropriate part of the object in order to get high-resolution images of the whole object. We propose an assignment scheme based on the analysis of a coarse 3D shape produced in a preprocessing step based on the wide-FOV images. For each high-resolution camera, we evaluate the visibility toward the different parts of the shape, corresponding to different orientations of the camera and with respect to its FOV. Then, we assign each camera to one orientation in order to get high visibility of the whole object. The continuously captured images are saved to be used offline in the reconstruction of the object. For a temporal extension of this scheme, we involve, in addition to the visibility analysis, the last camera orientation as an additional constraint. This allows smooth and optimized camera movements.