Extracting 3-D motions of individuals at work by uncalibrated multiple video cameras

A technique is described for recovering the motion of individuals in a 3D way employing multiple video cameras. The technique extends the measurement matrix employed in the factorization method so that it includes motion information. Advantages of the technique over others are that it is free from video camera calibration placed around individuals of interest and that it recovers their entire motion during an observation time all at once. The former contributes to simple video acquisition of motion, whereas the latter eliminates the step of motion registration in the time lapse. In the performed experiment, the technique was applied to 3D recovery of the respective motion of two persons performing indoor work and satisfactory results were obtained