In many applications the image registration task turns out to be a fundamental prerequisite for any further processing and analysis. In the proposed paper a new efficient technique is presented, appropriate for registering images which are translated and rotated versions of a reference image. The technique consists of two main parts: an efficiently implemented prewhitening part, and an iterative part which yields the unknown displacements after a few iterations. The cross-correlation operations involved in the iterative part are performed efficiently via a new scheme based on a proper partitioning of the images and the use of the FFT. Note that this efficient scheme is also applicable to the conventional spatial cross-correlation method. The new registration technique exhibits a superior performance as compared to the conventional cross-correlation method.