[1] Shang H X, Gao J X. Theories and industrial applications of optical interferometric NDT techniques: a review[J]. Insight, 51, 240-251(2009).

[2] Zhong X H, Zhang B Z, Lin M R et al. Analysis and correction of angioscope image distortion[J]. Chinese Journal of Lasers, 30, 377-379(2003).

[3] Kaur M, Lane P M, Menon C. Scanning and actuation techniques for cantilever-based fiber optic endoscopic scanners: a review[J]. Sensors, 21, 251(2021).

[4] Martelli S, Mazzei L, Canali C et al. Deep endoscope: intelligent duct inspection for the avionic industry[J]. IEEE Transactions on Industrial Informatics, 14, 1701-1711(2018).

[5] Iyer S, Sinha S K. A robust approach for automatic detection and segmentation of cracks in underground pipeline images[J]. Image and Vision Computing, 23, 921-933(2005).

[6] Chen H S, Lin Y H. An endoscopic system adopting a liquid crystal lens with an electrically tunable depth-of-field[J]. Optics Express, 21, 18079-18088(2013).

[7] Zhang Z Y. A flexible new technique for camera calibration[J]. IEEE Transactions on Pattern Analysis and Machine Intelligence, 22, 1330-1334(2000).

[8] Hartley R, Kang S B. Parameter-free radial distortion correction with center of distortion estimation[J]. IEEE Transactions on Pattern Analysis and Machine Intelligence, 29, 1309-1321(2007).

[9] Smith W E, Vakil N, Maislin S A. Correction of distortion in endoscope images[J]. IEEE Transactions on Medical Imaging, 11, 117-122(1992).

[10] Vijayan A K, Kumar S, Radhakrishnan D. A new approach for nonlinear distortion correction in endoscopic images based on least squares estimation[J]. IEEE Transactions on Medical Imaging, 18, 345-354(1999).

[11] Ahmed M, Farag A. Nonmetric calibration of camera lens distortion: differential methods and robust estimation[J]. IEEE Transactions on Image Processing, 14, 1215-1230(2005).

[12] Mundhenk T N, Rivett M J, Liao X Q et al. Techniques for fisheye lens calibration using a minimal number of measurements[J]. Proceedings of SPIE, 4197, 181-190(2000).

[13] Wang J H, Shi F H, Zhang J et al. A new calibration model of camera lens distortion[J]. Pattern Recognition, 41, 607-615(2008).

[14] Chen W Y, Xu J, Yang H et al. Distortion correction of single image based on deep learning[J]. Laser & Optoelectronics Progress, 57, 241504(2020).

[15] Sheng Q, Zheng J M, Shi W C et al. Measurement and modeling of reflection characteristics of hole inner surface based on endoscopic image[J]. Measurement, 190, 110742(2022).

[16] Jing W B, Gao X F, Huang B K et al. Expansion of conical catadioptric panoramic image of inner surface of cylindrical objects[J]. Acta Optica Sinica, 41, 0311002(2021).

[17] Shi Z Y, Fang Y M, Wang X Y. Research progress in gear machine vision inspection instrument and technology[J]. Laser & Optoelectronics Progress, 59, 1415006(2022).

[18] Sun F R, Liu J R. Fast Hough transform algorithm[J]. Chinese Journal of Computers, 24, 1102-1109(2001).

[19] Liang J X, Zhang L, Meng Y Y et al. An improved maize plant contour extraction method[EB/OL]. https://kns.cnki.net/kcms/detail/detail.aspx?dbcode=CAPJ &dbname=CAPJLAST&filename=JGDJ202207130EU&unip latform=NZKPT&v=cDi37wmKJEoXrBtF3jd1xpF2H_2LvxLxR oQSqpzKQHJyLnruu-sSw6MzIoHqONxn