1. School of Software, Engineering Research Center of Digital Forensics, Ministry of Education, Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China
2. School of Computer Science, Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China
3. College of Computer and Information, Hohai University, Nanjing, Jiangsu, China
4. Engineering Research Center of Digital Forensics, Ministry of Education, the School of Computer Science, Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China