[1] [1] Yuan Yuqing. Analysis on China′s high-rail diplomacy under the background of "the belt and road initiative"［D］. Nanjing: Nanjing University, 2016.

[2] [2] Li Jun. The design and implementation of TEDS system［D］. Beijing: Beijing University of Post and Telecommunications, 2012.

[3] [3] Sobel I. Camera models and machine perception［D］. California: Stanford University, 1970.

[4] [4] Guo Z H, Zhang L, Zhang D. A completed modeling of local binary pattern operator for texture classification［J］. IEEE Transactions on Image Processing, 2010, 19(6): 1657-1663.

[5] [5] Qiao Naosheng, Zhang Fen, Li Xiaoqin. Defect image preprocessing of printed circuit board［J］. Laser & Optoelectronics Progress, 2015, 52(2): 021003.

[6] [6] Song Xiaoyan, Bai Fuzhong, Wu Jianxin, et al. Wood knot defects recognition with gray-scale histogram features［J］. Laser & Optoelectronics Progress, 2015, 52 (3): 031501.

[7] [7] Mo Shaowen, Deng Xinpu, Wang Shuai, et al. Moving object detection algorithm based on improved visual background extractor［J］. Acta Optica Sinica, 2016, 36(6): 0615001.

[8] [8] Yang Sa, Yang Chunling. Image registration algorithm based on sparse random projection and scale-invariant feature transform［J］. Acta Optica Sinica, 2014, 34(11): 1110001.

[9] [9] Wang Xiangjun, Wang Yan, Li Zhi. Fast target recognition and tracking method based on characteristic corner［J］. Acta Optica Sinica, 2007, 27(2): 360-364.

[10] [10] Yang Sa, Xia Minghua, Zheng Zhishuo. Medical image registration algorithm based on polynomial deterministic matrix and SIFT transform［J］. Laser & Optoelectronics Progress, 2016, 53(8): 081002.

[11] [11] Ojala T, Pietikinen M, Menp T. Multiresolution gray-scale and rotation invariant texture classification with local binary patterns［J］. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2002, 24(7): 971-987.

[12] [12] Murala S, Maheshwari R, Balasubramanian R. Local tetra patterns: a new feature descriptor for content-based image retrieval［J］. IEEE Transactions on Image Processing, 2012, 21(5): 2874-2886.

[13] [13] Maji S, Berg A, Malik J. Classification using intersection kernel support vector machines is efficient［J］. IEEE Computer Vision and Pattern Recognition, 2008, 21: 1-8.

[14] [14] Lampert C, Blaschko M, Hofmann T. Efficient subwindow search: a branch and bound framework for object localization［J］. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2009, 31(12): 2129-2142.

[15] [15] Gao Jun, Xie Zhao. Theory and method of image understanding［M］. Beijing: Science Press, 2009.

[16] [16] Zhou F Q, Zou R, Qiu Y F, et al. Automated visual inspection of angle cocks during train operation［J］. Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail & Rapid Transit, 2013, 228(7): 794-806.