1. Chongqing Key Laboratory of Image Cognition, Chongqing University of Posts and Telecommunications, Chongqing, China
2. School of Software Engineering, Chongqing University of Posts and Telecommunications, Chongqing, China
3. College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, China
4. Multimedia Signal Processing Group, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland