“…In the first step, the similarity between images is computed using an appropriate mathematical model, such as: image differencing, log-ratio, change vector analysis (CVA), correlation coefficient (CC), erreur relative globale adimensionnelle de synthese (ERGAS), and so on. The second step is used to obtain binary change mask, which can be achieved by optimization methods [5], [6], thresholding [8], clustering approach [9], and many others [10]. For instance, Ghosh et al [11] propose an unsupervised change detection technique for multispectral remote sensing images.…”