2.4.3 Line Filters [1]

Line filters are similar to edge filters in that they are directional and size sensitive (different size convolution kernals for different thickness lines). Here is an example for single width lines (after Adjust Auto Levels):

Original

-1 2 -1 -1 2 -1 -1 2 -1		-1 -1 -1 2 2 2 -1 -1 -1
-1 -1 2 -1 2 -1 2 -1 -1		2 -1 -1 -1 2 -1 -1 -1 2

Here too absolute value in the calculation would improve the result.

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