1. School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
2. Key Laboratory of Nondestructive Testing, Ministry of Education, Nanchang Hangkong University, Nanchang, China
3. National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China
4. School of Measuring and Optical Engineering, Nanchang Hangkong University, Nanchang, China