The two-stage matching method can be used to improve the result of digital image correlation . Choosing the best matching target size which is decided by the range of the peak of central target area can increase the effects in the practical use . The Fast Fourier Transformation (FFT) method presented herein is a very fast and rigorous method of the image matching The main advantage of FFT method is its computational efficiency. It requires , for the computation of the image matching for all interested points , the FFT method provides the means for spectral and correlation analysis between target sizes and results of the matching. A comparison of the two-stage and FFT methods is given which involves theories,procedures ,processing times,and matching precision. Various statistical tests are performed in order to diagnose possible systematic effects.
Jin-Tsong Hwang, Jin-Tsong Hwang,
"Comparing the image matching methods of the two-stage and FFT", Proc. SPIE 1395, Close-Range Photogrammetry Meets Machine Vision, 13953O (1 August 1990); doi: 10.1117/12.2294375; https://doi.org/10.1117/12.2294375