DCT sign only correlation and its application to image registration

This paper presents DCT sign only correlation (DSOC) method for image registration, the task that previously can be accomplished by phase only correlation (POC) method. The POC function corresponds to phase information of the DFT coefficients. In the DCT case, all DCT coefficients are real values, as a result, the phase information corresponds to the sign of DCT coefficients. Three DSOC methods are described and their suitability for image registration is discussed.