Method and apparatus for tracking the motion of image content in a video frames sequence using sub-pixel resolution motion estimation

An apparatus for tracking motion of an image content, wherein the image content is selected from a point of interest or an object or a group of pixels, in a video frames sequence using sub-pixel resolution motion estimation, said apparatus comprising means adapted to:

• a) estimate the motion of an image content between a reference frame and a following or preceding frame, starting from an integer pixel position in said reference frame;
• b) if an end point of a corresponding motion vector has a position between integer pixel positions in said following or preceding frame, replace the coordinates of said motion vector end point with the coordinates of an adjacent integer pixel position in said following or preceding frame, and store an error value between said end point coordinates and said replacement coordinates;
• c) define said following or preceding frame as a current frame, and estimate the motion of said image content between said replacement coordinates in said current frame and said following or preceding frame;
• and
• d) correct said following or preceding frame end point coordinates of the corresponding motion vector by using said stored error value in opposite direction, so as to get a corresponding precise motion vector.

An apparatus for tracking motion of an image content, wherein the image content is selected from a point of interest or an object or a group of pixels, in a video frames sequence using sub-pixel resolution motion estimation, comprising:

• a memory that stores data which control operation of a processor;
• said processor, which executes a procedure comprising:
• a) estimating the motion of an image content between a reference frame and a following or preceding frame, starting from an integer pixel position in said reference frame;
• b) if an end point of a corresponding motion vector has a position between integer pixel positions in said following or preceding frame, replacing the coordinates of said motion vector end point with the coordinates of an adjacent integer pixel position in said following or preceding frame, and storing an error value between said end point coordinates and said replacement coordinates;
• c) defining said following or preceding frame as a current frame, and estimating the motion of said image content between said replacement coordinates in said current frame and said following or preceding frame;
• and
• d) correcting said following or preceding frame end point coordinates of the corresponding motion vector by using said stored error value in opposite direction, so as to get a corresponding precise motion vector.