A practical semi-automatic approach for optical and SAR data co-registration

With the increasing applications of multi-source remote sensing, the synergistic use of optical and SAR remote sensing images is becoming more and more frequently used. However, an effective and efficient application of both optical and SAR remote sensing remains a challenging task due to a number of factors. One of the challenging task is the co-registration between optical and SAR images. This study aims to propose a practical semi-automatic approach for optical and SAR co-registration. The basic idea of the proposed approach is based on the characteristics of optical and SAR images. With a number of initial homologous points generated automatically at the beginning step, an automatic adjustment of the initial homologous pairs is applied to optimize the initial homologous points subject to a given threshold of Root Mean Square Errors (RMSE) of the co-registration. Experimental results demonstrate the promising effectiveness of the proposed approach with a great reduction from more than 20 pixels to approximate zero pixel of the RMSE of the initial homologous points.