计算机工程与应用 ›› 2013, Vol. 49 ›› Issue (16): 179-182.

• 图形图像处理 • 上一篇    下一篇

编码器光栅表面缺陷图像小波去噪

王义文1,冯  超1,刘献礼1,廖益龙1,权超健1,梅  恒2,林长友2   

  1. 1.哈尔滨理工大学 机械动力工程学院,哈尔滨 150080
    2.长春禹衡光学有限公司,长春 130012
  • 出版日期:2013-08-15 发布日期:2013-08-15

Encoder circular grating surface defect image wavelet denoising

WANG Yiwen1, FENG Chao1, LIU Xianli1, LIAO Yilong1, QUAN Chaojian1, MEI Heng2, LIN Changyou2   

  1. 1.School of Mechanical & Power Engineering, Harbin University of Science & Technology, Harbin 150080, China
    2.Changchun Yuheng Optics Co., Ltd, Changchun 130012, China
  • Online:2013-08-15 Published:2013-08-15

摘要: 为了提高光栅表面缺陷图像的去噪效果,便于后续缺陷图像检测,通过改进阀值和阀值函数来实现对光栅表面缺陷图像的小波去噪。通过引入一个收缩因子来改进原阀值,得到各分解尺度上的新阀值,利用新阀值函数对各尺度上的小波高频系数进行阀值处理,经过小波逆变换得到去噪后的光栅表面缺陷图像。实验结果表明,该方法与硬、软阀值法相比,提高了峰值信噪比,较好地保留了缺陷图像的边缘等细节信息,增强了边缘对比度,且图像更平滑。

关键词: 光栅, 表面缺陷检测, 收缩因子, 阀值函数, 小波去噪

Abstract: To improve the de-noising effects for circular grating surface defect image and easily detect defect image, improved threshold value and threshing function are proposed for the de-noising of circular grating surface defect image by wavelet. A new threshold on the respective scale decomposition can be obtained by introducing a shrinkage factor to improve the original threshold value. Wavelet high frequency coefficients on the respective scale decomposition are processed by new threshing function. The denoised circular grating surface defect image is obtained by wavelet inverse transformation. Experimental results show that compared to the hard and soft threshold method, this method has improved the PSNR, well keeps the defect image edges and other details, enhances the edge contrat, and obtains a smoother image.

Key words: circular grating, surface defect detection, shrinkage factor, threshing function, wavelet denoising