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

Motion estimation is a temporal image compression technique, where an nxn 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 estimation is proposed. The proposed technique, first, reduces the n-bit grayscale frames into 1-bit binary frames using morphological filters, and determines the displacement of the edge features of the adjacent frames. While reduction in bit depth requires a small percentage of computation using the full pixel resolution, the search procedure is performed by simple XOR logic 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 operations, and possesses a higher degree of parallelism when implemented on a two-dimensional single-instruction stream, multiple-data stream architecture.