Cross-Spectral Face Matching Based on Phase Correlation

One way to identify human faces is by using facial features or facial patterns based on visible images. However, this approach depends on the lighting conditions. In a poor illumination environment, it is difficult to recognize the face images. Thermal images do not rely on the illumination condition; thus can overcome this problem. Unlike the visible image, the thermal images lack visual information. Therefore, matching between the thermal and visible images (cross-spectral matching) is vital in face recognition. This paper proposed a phase correlation method, namely phase-only correlation (POC) and band-limited POC (BLPOC), for a cross-spectral matching of face images. First, the Fourier transform was applied to face images in both spectral domains, and the phase correlation between the two images was calculated. The experimental results showed that, from 100 visible and thermal image (acquired by FLIR C2 camera) pairs, the BLPOC resulted in significant correlation values compared to POC.