Embodiments form a calibrated biomechanical skeleton from images including a scale frame and a motion capture subject. Links and joints for the biomechanical skeleton are overlaid on a silhouette created for each image in a sequence of captured images. A true length for each link and an accurate position for each biomechanical reference location are determined from a comparison of true dimensions of the scale frame to measurements taken from recorded camera images. The motion capture subject may perform a sequence of calibration motions to allow joint locations in the biomechanical skeleton to be positioned accurately over corresponding skeletal joints in the motion capture subject. Accurate link lengths for the biomechanical skeleton may be determined by compensating measured link lengths in images with true dimensions of struts and calibration markers included in the scale frame.
