Low complexity block motion estimation using morphological-based feature extraction and XOR operations

Motion estimation is a temporal image compression technique, where an n x n block of pixels in the current frame of a video sequence is represented by a motion vector with respect to the best matched block in a search area of the previous frame. In this paper, a low complexity technique for motion e stimation is proposed. The proposed technique, first, reduces the n-bit gra yscale frames into 1-bit binary frames using morphological filters, and det ermines the displacement of the edge features of the adjacent frames. While reduction in bit depth requires a small percentage of computation using th e full pixel resolution, the search procedure is performed by simple XOR lo gic operations and 1-b distortion accumulations on the entire search area. Compared to other low complexity techniques, the proposed technique yields better frame reconstruction, operates using simpler arithmetic/logic operat ions, and possesses a higher degree of parallelism when implemented on a tw o-dimensional single-instruction stream, multiple-data stream architecture. (C) 2000 SPIE and IS&T. [S1017-9909(00)01302-7].