**6. Acknowledgment**

Special thanks to go the group of Ohya Laboratory, Global Information and Telecommunication Studies (GITS), Waseda University, Japan, and the group of the Laboratory of Image Science and Technology (LIST), School of Computer Science and Engineering, Southeast University, China, for their contribution and discussion on various aspects and projects associated with image segmentation. The authors would like to thank the reviewers for their valuable suggestions for improving this manuscript.
