Custom Threshold Denoising for Crack Signal Using Wavelet Transform

The study investigated the effectiveness of a custom threshold denoising method for processing crack signals using wavelet transform. The optimal parameters for the denoising method were identified as the Db12 wavelet basis function, 3-level wavelet decomposition, and hard threshold function. This selection was based on the evaluation rule that prioritizes a higher signal-to-noise ratio (SNR) and a smaller root mean square error (RMSE).

The results indicate that the custom wavelet coefficient thresholding method, implemented for each decomposition level, exhibits superior denoising performance compared to other signal denoising methods. Notably, this method effectively preserves crack information to a greater extent. This outcome provides strong evidence for the feasibility and efficacy of the custom threshold denoising approach in processing crack signals.