SYSTEM AND METHOD FOR CROSS CORRELATION WITH APPLICATION TO VIDEO MOTION VECTOR ESTIMATION

摘要

The present invention describes a method and apparatus that efficiently computes the summation (1) hereinafter called simply the "cross correlation". The method presented here converts two blocks, both the macro block and the search block, to their frequency domain representation via the Discrete Fourier Transform (DFT) and then multiplies the two blocks together to form a product matrix in the frequency domain. The frequency domain result is then converted back to spatial domain and the cross correlation values are simultaneously available to be searched for the maximum value. A complete method for this computation is disclosed, including several particularly innovative approaches which make the method attractive for implementation in hardware is disclosed. The cross correlation method of the present patent includes an SIMD architecture which efficiently performs a wide variety of elementary subroutines, including those needed for cross correlation computation.