A method comprises searching in a video stream a first frame and a second frame that each has enough point correspondence with a image model, wherein the first frame is the nearest previous frame prior to a third frame, and the second frame is the nearest subsequent frame to follow the third frame. The method further comprises calculating an interpolation between a first mapping matrix of the first frame and a second mapping matrix of the second frame to obtain a third mapping matrix of the third frame that has insufficient point correspondence with the image model.