Denoising of line structured light welded seams image based on adaptive top-hat transform
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摘要: 为了滤除焊接过程中大量散射及飞溅焊渣等噪声,提出了一种基于自适应顶帽变换(adaptive Top-Hat transform)的线结构光焊接图像去噪方法. 将噪声图像进行一定范围结构元尺寸的Top-Hat变换处理,提出了一种评价指标互相关系数(cross-correlation coefficient of image histogram, CCIH)选取得到最优结构元尺寸L. 其次,进行一定迭代次数范围的顶帽变换(Top-Hat)变换处理,并提出一种基于最大类间方差(Otsu)改进结构相似度(SSIM)算法的评价指标相亮比(ratio of structural similarity index to average brightness,RSB)选取得到最优迭代次数I. 结果表明,与自适应中值法(median filter,MF)、全变分法(total variation,TV)和非下采样轮廓波变换与全变差法相结合的方法(non-subsampled contourlet transform with total variation,NSCT-TV)相比,该方法在主观视觉效果,信息熵(entropy,EN)、峰值信噪比(peak signal-to-noise ratio,PSNR)和均方根误差(mean-square error,MSE)上均有较大的改善. 噪声得到有效去除的同时图像中的线结构光区域得到较好的保留.Abstract: Due to the scattering of the welding material, surface shape and laser line, the brightness distribution of the line structure is uneven and there are a lot of scattering noise around it, which affects the subsequent feature point extraction. In order to filter out the noise of the weld image of line structured light, a denoising model of weld image based on adaptive Top-Hat transformation is proposed. First, the noise image is transformed to a certain range of structural element size by Top-hat transform, and then an evaluation index was proposed, cross-correlation coefficient of image histogram (CCIH), and the optimal structural element size L is selected. Second, on the premise of the optimal structural element size L, the noise image is processed by the top-hat transform with a certain range of iterations times, a new model based on Otsu proposed SSIM model is proposed to select the optimal iterations time I from the evaluation index, Ratio of Structural Similarity Index to Average Brightness (RSB). Experimental results show that, compared with the method of Median Filter (MF), the method of Total Variation (TV), and the method combining Non-Subsampled Contourlet Transform with Total Variation (NSCT-TV), the proposed method has a great improvement in the aspects of subjective visual effect, entropy (EN), peak signal-to-noise ratio (PSNR) and mean-square error (MSE). Noise is suppressed more effectively and the line structured light area is preserved better in the image.
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表 1 去噪效果客观指标对比
Table 1 Comparison of objective indicators of denoising effect
焊接图像 评价指标 原始图像 自适应中值(MF) 全变分(TV)[20] 非下采样全变分(NSCT-TV)[21] 文中算法 第一组 EN 7.593 6 7.077 3 7.080 5 7.064 1 4.014 3 PSNR − 9.935 5 16.067 3 16.655 1 36.935 5 MSE − 1 429.728 8 153.342 7 133.930 4 62.929 0 第二组 EN 7.627 8 7.136 8 7.040 2 6.902 5 4.095 6 PSNR − 9.923 2 13.941 7 14.035 2 34.923 2 MSE − 1248.230 3 252.187 7 146.817 3 63.615 37 第三组 EN 8.247 6 7.219 9 7.205 1 7.201 8 4.299 1 PSNR − 7.769 7 13.969 5 18.154 5 38.264 3 MSE − 1 086.774 1 126.945 6 126.069 2 9.697 4 第四组 EN 8.240 0 7.217 3 7.245 3 7.222 7 4.103 9 PSNR − 6.797 3 19.281 0 19.763 2 37.479 6 MSE − 1359.404 1 767.319 1 686.695 5 11.617 8 -
[1] Chen X Z, Li T, Lang Y Y, et al. Edge detection and its application to recognition of arc weld image[J]. China Welding, 2007, 16(4): 20 − 26.
[2] 郭吉昌, 朱志明, 孙博文. 基于组合激光结构光的多功能视觉传感器[J]. 焊接学报, 2019, 40(10): 1 − 7. Guo Jichang, Zhu Zhiming, Sun Bowen. A multifunctional monocular visual sensor based on combined laser structured lights[J]. Transactions of the China Welding Institution, 2019, 40(10): 1 − 7.
[3] Agarwal G, Gao H, Amirthalingam M, et al. In situ strain investigation during laser welding using digital image correlation and finite-element-based numerical simulation[J]. Science and Technology of Welding and Joining, 2018, 23(2): 134 − 139. doi: 10.1080/13621718.2017.1344373
[4] Huo P, Li X, Pei W C. Arithmetic processing of image of weld seam based on morphological filtering[J]. Communications in Computer & Information Science, 2010, 106: 305 − 311.
[5] Chang C L, Chen Y H. Measurements of weld geometry using image processing technology[J]. Key Engineering Materials, 2010, 437: 449 − 452. doi: 10.4028/www.scientific.net/KEM.437.449
[6] Floris G, Anwar M, Teun B, et al. Improving source camera identification using a simplified total variation based noise removal algorithm[J]. Digital Investigation, 2013, 10(3): 207 − 214. doi: 10.1016/j.diin.2013.08.002
[7] Duan J X, Luo L, Gao X R, et al. Multiframe ultrasonic tofd weld inspection imaging based on wavelet transform and image registration[J]. Hindawi, 2018: 101 − 155.
[8] Padmagireeshan S J, Johnson R C, Balakrishnan A A, et al. Performance analysis of magnetic resonance image denoising using contourlet transform[C]//Third International Conference on Advances in Computing & Communications. IEEE, 2013: 396-399.
[9] Tian X L, Jiao L C, Guo K W. An affinity-based algorithm in nonsubsampled contourlet transform domain: application to synthetic aperture radar image denoising[J]. Journal of Signal Processing Systems, 2016, 83(3): 373 − 388. doi: 10.1007/s11265-015-1024-2
[10] Siblini A, Audi K, Ghaith A. Power-based pulsed radar detection using wavelet denoising and spectral threshold with pattern analysis[J]. International Journal of Microwave and Wireless Technologies, 2020, 12(8): 782 − 789. doi: 10.1017/S1759078720000124
[11] Wu H L, Xu H P, Wang P B, et al. Denoising method based on intrascale correlation in nonsubsampled contourlet transform for synthetic aperture radar images[J]. Journal of Applied Remote Sensing, 2019, 13(4): 046503 − 046503.
[12] Sebastian V B, Unnikrishnan A, Balakrishnan K, et al. Morphological filtering on hypergraphs[J]. Discrete Applied Mathematics, 2014, 216: 307 − 320.
[13] He G Q, Zhang Q J, Ji J J, et al. An infrared and visible image fusion method based upon multi-scale and top-hat transforms[J]. Chinese Physics B, 2018, 27(11): 344 − 352.
[14] Wei N, Yang J H, Liu R X. Denoising for variable density ESPI fringes in nondestructive testing by an adaptive multiscale morphological filter based on local mean[J]. Applied Optics, 2019, 58(28): 7749 − 7759. doi: 10.1364/AO.58.007749
[15] Hematizadeh A, Jazayeri M, Ghafary B. Generation of terahertz radiation via cosh-Gaussian and top-hat laser beams in a collisional magnetized plasma[J]. Contributions to Plasma Physics, 2018, 58(1): 578 − 586.
[16] Huang J, Deng K, Yao Z. Using top-hat beam to improve the performance of the inter-satellite laser communication[J]. Optik - International Journal for Light and Electron Optics, 2017, 137: 238 − 243. doi: 10.1016/j.ijleo.2017.03.010
[17] 孙博文, 朱志明, 郭吉昌, 等. 基于组合激光结构光的视觉传感器检测算法及图像处理流程优化[J]. 清华大学学报(自然科学版), 2019, 59(6): 445 − 452. Sun Bowen, Zhu Zhiming, Guo Jichang, et al. Detection algorithms and optimization of image processing for visual sensors using combined laser structured light[J]. Journal of Tsinghua University (Natural Science Edition), 2019, 59(6): 445 − 452.
[18] 毛志伟, 赵滨, 周少玲. 线结构光视觉传感焊缝跟踪图像处理[J]. 热加工工艺, 2016, 45(15): 233 − 235+238. Mao Zhiwei, Zhao Bin, Zhou Shaoling. Image processing of line structured light vision sensing seam tracking[J]. Thermal processing technology, 2016, 45(15): 233 − 235+238.
[19] 于岩, 成敏. 荧光图像增强去噪的自适应顶帽变换算法[J]. 电脑与电信, 2013(4): 42 − 44. doi: 10.3969/j.issn.1008-6609.2013.04.028 Yu Yan, Cheng Min. An Adaptive Top-Hat algorithm for fluorescence image processing[J]. Computer and Telecommunication, 2013(4): 42 − 44. doi: 10.3969/j.issn.1008-6609.2013.04.028
[20] 张鹏贤, 韦志成, 刘志辉. 管道焊口间隙量与错边量的激光视觉检测[J]. 焊接学报, 2018, 39(11): 103 − 107. doi: 10.12073/j.hjxb.2018390282 Zhang Pengxian, Wei Zhicheng, Liu Zhihui. Laser visual measurement for gap values and misalignment values of pipeline welding groove[J]. Transactions of the China Welding Institution, 2018, 39(11): 103 − 107. doi: 10.12073/j.hjxb.2018390282
[21] Wu Y Q, Wan H, Ye Z L, et al. Noise reduction of welding defect image based on NSCT and anisotropic diffusion[J]. Springer Berlin Heidelberg, 2014, 20(1): 60 − 65.
[22] Li J W, Cheng W, Bao L L, et al. An improved method for blind detection of multi-node cooperative spectrum based on correlation coefficient[J]. Journal of Physics: Conference Series, 2018, 1087(2): 022031 − 022039.
[23] Wang Z, Bovik A C, Sheikh H R, et al. Image quality assessment: from error visibility to structural similarity[J]. IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society, 2004, 13(4): 600 − 12. doi: 10.1109/TIP.2003.819861
[24] Onumanyi A J, Onwuka E N, Aibinu A M, et al. A modified Otsu’s algorithm for improving the performance of the energy detector in cognitive radio[J]. AEU-International Journal of Electronics and Communications, 2017, 79: 53 − 63.
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