75. The method of claim 73 , further comprising: allocating computing resource to one tracking process selected from the motion-assisted object tracking process and the secondary object tracking process with a priority higher than the other tracking process; and responsive to total computer resource allocated to both the motion-assisted object tracking process and the secondary object tracking process exceeding a predetermined threshold, disabling one of the object tracking processes temporally.
73. The method of claim 72 , wherein tracking the object contained in the plurality of video frames capturing the visual gesture by the motion-assisted object tracking process and the secondary object tracking process in parallel comprises: obtaining a first set of estimates of a center point position of the ROI containing the object and a size of the ROI based on the object tracking by the motion-assisted object tracking process; and obtaining a second set of estimates of the center point position of the ROI containing the object and the size of the ROI based on the object tracking by the secondary object tracking process.