Detection of central positions of noisy rounded square function using modified Haar wavelet transform and Haar-Gaussian wavelet transform
Feijun Song, Yu Lei, Suganda Jutamulia · Optical Engineering · 2000
We propose and demonstrate new wavelet transforms, the modified Haar wavelet transform and Haar-Gaussian wavelet transform, for the detection of central positions of a noisy rounded square function. The advantage is the immunity of the wavelet transform to random noise. The alternative technique based on first- and second-order differentiation cannot be applied when the signal function is corrupted by noise. The proposed technique can be used for lead inspection of surface mount devices in the electronic industry. © 2000 Society of Photo-Optical Instrumenta- tion Engineers. (S0091-3286(00)01705-0)