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Restoration by Inverse Filtering

Taking Fourier transform of the above convolution, we get


G(fx)=F(fx)H(fx)

where G, F, and H are the spectra of g, f and h, respectively. Specifically, we have

\begin{displaymath}H(f_x)=\int_{-\infty}^{\infty} h(x) e^{-j2\pi x f_x} dx
=\int...
...\pi x f_x} dx = e^{-j\pi Lf_x}\frac{sin(\pi L f_x)}{\pi f_x v}
\end{displaymath}

While the inverse filtering method could be applied to restore f(x) by inverse transforming F(fx)

\begin{displaymath}F(f_x)=\frac{G(f_x)}{H(f_x)} \end{displaymath}

we also realize that those points of F(fx) corresponding to H(fx)=0at $f_x=k/L,\;\;(k=\pm 1, \pm 2, \cdots)$ can never be restored. Interpolation from the neighboring points would not work (why?).

Moreover, this inverse filtering method is sensitive to noise that may exist in the imaging process.



Ruye Wang
2000-03-31