(a)

(b)

(c)

(d)

Figure 10: (a) denoised signals for defect-free, gouged, and dent pipes. Continuous wavelet transforms for defect-free, gouged, and dented pipes when pipes are embedded in soil, (b) for Daubechies (db4) function, (c) for Symlet (sym4) function, (d) for Meyer function.