17.8 The Generic Filters

There are only three filters in the Generic menu, and only the first one has a dialog. The filters in this section are only vaguely related; all of them use a matrix to calculate new pixel values, which is a common property of filters. The truth is, the three filters in this menu are here because they didn’t fit anywhere else.

Convolution Matrix

Convolution Matrix can rightly be called a generic filter, since it’s used to generate custom filters for blurring, sharpening, embossing, inverting, and much more.

The main part of the dialog, shown in Figure 17-135, is the MATRIX,a 5 × 5 array of numbers. The middle box corresponds to the current pixel. The other boxes correspond to the neighboring pixels. The filter works by multiplying ...

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