基于db N小波变换和自适应高斯滤波的齿面干涉图像相位滤波方法

齿轮齿面形貌的激光干涉测量中,由于齿面高度差较大,采集到的干涉图像中难以避免存在条纹密集区域,容易出现局部条纹粘连、错切等现象,增加了相位噪声和解包裹难度。分析了包裹相位图中条纹密度分布规律,提出了一种基于db N小波变换和自适应高斯滤波的齿面干涉图像相位去噪方法。首先,利用小波变换分解出包裹相位图中常表现为高频信号的噪声,采用软阈值去噪滤除部分高频噪声;其次,根据包裹相位图频域特征,结合自适应高斯滤波进一步对高频噪声进行迭代滤波处理;最后,设计了相关实验,通过与经典的滤波方法进行对比,所提方法不仅能够有效滤除条纹较为密集的包裹相位图中的相位噪声,而且更大限度地保留了图像细节信息,证明了所提方法的有效性和正确性。

Phase Filtering Method of Tooth Surface Interference Image Based on dbN Wavelet Transform and Adaptive Gaussian Filtering

In the laser interferometry of gear tooth surface topography , due to the large height difference of tooth surface , it is difficult to avoid the presence of dense fringe areas in the collected interference images , which are prone to local fringead hesion and miscutting , increasing the difficulty of phase noise and unwrapping.In this paper , the fringe density distribution in the wrapped phase image is analyzed , and a phase denoising method based on dbN wavelet transform and adaptive Gaussian filter is proposed.Firstly , the wavelet transform is used to decompose the high-frequency noise in the wrapped phase map , and the soft threshold is used to remove some high-frequency noise.Secondly , according to the frequency domain characteristics of the wrapped phase pattern , the high-frequency noise was further filtered iteratively with adaptive Gaussian filter.Finally , the relevant experiments are designed.Compared with the classical filtering methods , the proposed method can not only effectively filter out the phase noise in the densely fringed phase map , but also retain the image details to a greater extent , which proves the effectiveness and correctness of the proposed method.