A Subpixel Image Matching Technique Using Phase-Only Correlation

This paper presents a high-accuracy image matching technique using a phase-only correlation (POC) function. The POC-based image matching enables estimation of image displacements with 1/10~1/100-pixel accuracy by a function fitting technique using the closed-form representation of the POC function´s peak. This method requires an iterative process for the nonlinear function fitting, resulting in long computation times. In this paper, we propose a peak evaluation formula (PEF) that directly estimates the correlation peak location from actual 2-D data array of the POC function. Experimental evaluation shows that the proposed method reduces computation time without sacrificing image matching accuracy