Image Processing Laplacian Filter The Laplacian operation also acts like a circular gradient filter. This has the effect of high- lighting all edges (gradients) in the image. The kernel size can be 3, 5 or 7. The absolute clip- ping method is usually used with this filtering operation. The kernels used by the Image Processing Tool are shown in the following figure. Laplacian Filtering Kernels Sharpen Filter The Sharpen operation sets each pixel in the output image as the subtraction of the average of all the input image pixels in the neighborhood defined by the selected kernel size. This has the effect of sharpening the image, especially edges. The kernel size can be 3, 5 or 7.
The ker- nels used by the Image Processing Tool are shown in the following figure. Sharpen Filtering Kernels ACEUser's Guide, 3.6.x, 18316-000 Rev A Page 518