US Patent 7796120 Method and apparatus for detecting image movement

A method of detecting image movement is provided. A reference frame is accessed, and a reference window is captured from the reference frame. A sampling frame is then accessed. When the reference window has not reached the margin of the reference frame, a new window is captured from the reference frame to replace the reference window. From the reference frame, a window matching the reference window is searched and a moving vector is calculated. When the sampling window reaches the margin of the sampling frame, the sampling frame replaces the reference frame. Another reference window is also captured from the reference frame, and the step of accessing the sampling frame is repeated.