Segment-based motion estimation

A method to determine motion vectors for respective segments (S 11 -S 14 ) of a segmented image ( 100 ) comprises: creating sets of candidate motion vectors for the respective segments (S 11 -S 14 ); dividing the segmented image ( 100 ) into a grid of blocks (b 11 -b 88 ) of pixels; determining for the blocks (b 11 -b 88 ) of pixels which of the candidate motion vectors belong to the blocks (b 11 -b 88 ), on basis of the segments (S 11 -S 14 ) and the locations of the blocks (b 11 -b 88 ) within the segmented image ( 100 ); computing partial match errors for the blocks (b 11 -b 88 ) on basis of the determined candidate motion vectors and on basis of pixel values of a further image ( 102 ); combining the partial match errors into a number of match errors per segment; selecting for each of the sets of candidate motion vectors respective candidate motion vectors on basis of the match errors; and assigning the selected candidate motion vectors as the motion vectors for the respective segments (S 11 -S 14 ).