7[2]Burch S. Digital enhancement of video images for NDT. NDT International, 1987,20(1): 51～56.
8[3]Throup D. Improving images from real time radioscopic sources, X-ray Real-Time Radiography and Image Processing, R., Halmshaw, Ed., Sym. British Inst. NDT Newbury, Berkshire, 1988. 87～95.
9[4]Pratt W K. Digital Image Processing, John Wiley & Sons, Inc., 1978. 307～342.
10[5]Chen, Shuyue. Study on the improvement of X-ray digital radiography quality, Ph.D. Dissertation, Nanjing University of Sci. and Tech., 2001.
