[Ding, Xiangling] Hunan Univ Sci & Technol, Sch Comp Sci & Engn, Xiangtan, Peoples R China.^[Ding, Xiangling] Guangdong Key Lab Intelligent Informat Proc, Shenzhen, Peoples R China.^[Ding, Xiangling] Shenzhen Key Lab Media Secur, Shenzhen, Peoples R China.^[Ding, Xiangling] Chinese Acad Sci, Inst Informat Engn, State Key Lab Informat Secur, Beijing, Peoples R China.^[Ding, Xiangling] Zhengzhou Xinda Inst Adv Technol, Zhengzhou, Peoples R China.^[Ding, Xiangling] Hunan Key Lab Serv Comp & Novel Software Technol, Xiangtan, Peoples R China.^[Ding, Xiangling] Guangdong Key Lab Informat Secur Technol, Guangzhou, Peoples R China.^[Zhu, Wenjie;Zhang, Dengyong] Changsha Univ Sci & Techno, Sch Comp & Commun Engn, Changsha, Peoples R China.