Simple noncircular correlation method for exhaustive sum square difference matching

We propose a new algorithm to calculate the sum square difference (SSD) metric for estimating translational motion. Using some substitutions and complex arithmetics, computation of the SSD is derived to be a correlation function of two substituting functions. The former can be computed using the fast Fourier transform (FFT) approach, which is less computationally expensive than the direct computation of the SSD. Zero padding of the block is useful both to avoid the circular character of the FFT and to computes the SSD function at once. We prove the existence of a simple and optimal correlation method for noncircular SSD matching. (c) 2007 Society of Photo-Optical Instrumentation Engineers.