This invention relates to detection of motion of images represented by video pixels and other digital data.
One application of this invention is useful in connection with digitally removing noise from video sequences that have been digitized from the analog domain in order to increase the efficiency of a digital video compression system. Other applications of the invention are useful in connection with deinterlacing (line doubling) systems, and with comb filtering systems.
Some known temporal filters derive motion information from both luminance and chrominance separately, not taking advantage of the correlation between the two signals.
Prior art systems have failed to recognize the utility of a median filter operation in the motion detection path which is used to eliminate impulses not in the image domain but in the motion/temporal domain. This operation makes a recursive filter perform better by controlling the value of the coefficient that controls the recursive time constant of the filter itself.
There are known temporal noise reduction systems that use motion estimation techniques instead of motion detection techniques. However, the motion estimation process is complex and does not fully guarantee the elimination of noise, just reduction.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.