摘要
针对硬阈值函数在阈值处不连续、软阈值函数虽然为连续函数但有固定偏差的问题,在分析了硬阈值函数、软阈值函数和几种代表性的改进阈值函数的优缺点后,提出一种改进阈值函数的小波去噪算法,并利用MATLAB软件进行了仿真验证,结果表明,所提出的改进阈值函数具有较好的去噪效果。进一步将该算法应用到超声波衍射时差(TOFD)检测图像的去噪中,结果表明所提出的改进阈值函数在TOFD检测中具有较好的应用效果。
Aiming at the problem that the hard threshold function was discontinuous at the threshold and the soft threshold function was a continuous function but had a fixed deviation,after analyzing the advantages and disadvantages of the hard threshold function,the soft threshold function and several representative improved threshold functions,a wavelet denoising algorithm for the improved threshold function was proposed,and the MATLAB software was used for simulation verification.The experimental results showed that proposed improved threshold function had a good denoising performance.Further applying this algorithm to the denoising of TOFD images,the results showed that the proposed improved threshold function had good application performance in TOFD detection.
作者
薛峰
XUE Feng(Shanghai Research Institute of Materials Co.,Ltd.,Shanghai 200437,China;Shanghai Key Laboratory of Engineering Materials Application and Evaluation,Shanghai 200437,China)
出处
《无损检测》
CAS
2023年第8期62-66,共5页
Nondestructive Testing
关键词
图像去噪
小波变换
阈值函数
超声波衍射时差法
无损检测
image denoising
wavelet transform
threshold function
time-of-flight diffraction
nondestructive testing
