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13.3.5.5 Laplacian Filter

The Laplacian is used to enhance discontinuities. The 3x3 kernel is:

\begin{displaymath}
\left[
\begin{array}{r r r}
0 & -1 & 0 \\
-1 & 4 & -1 \\
0 & -1 & 0 \\
\end{array}
\right]
\end{displaymath}

and the 5x5 is:

\begin{displaymath}
\left[
\begin{array}{r r r r r}
-1 & -1 & -1 & -1 & -1 \\
-...
... & -1 & -1 \\
-1 & -1 & -1 & -1 & -1 \\
\end{array}
\right]
\end{displaymath}



2001-01-10