Applying Edge effects

Edge effects are applied to the edges in an image or selection. You can dilate, enhance, erode, find, and trace the edges in an image to create interesting results.

Important! These effects work on grayscale and 16 million–color (24-bit) images only. For more information about increasing the color depth of an image, see Increasing the color depth of an image.

The Dilate effect enhances the light areas of an image or selection. You can apply the Dilate effect by choosing Effects  Edge Effects  Dilate.

The Enhance effect increases the contrast along the edges in an image. You can apply the Enhance effect by choosing Effects  Edge Effects  Enhance.

The Enhance More effect applies a stronger contrast to the edges in an image than the Enhance effect does. You can apply the Enhance More effect by choosing Effects  Edge Effects  Enhance More.

The Erode effect enhances the dark areas in an image. You can apply the Erode effect box by choosing Effects  Edge Effects  Erode.

The Find All effect enhances the contrast between light and dark in an image by darkening the image and then highlighting the edges. You can apply the Find All Edges effect by choosing Effects  Edge Effects  Find All.

The Find Horizontal effect enhances the contrast between light and dark in an image by darkening the image and then highlighting the horizontal edges. You can apply the Find Horizontal edges by choosing Effects  Edge Effects  Find Horizontal.

The Find Vertical effect enhances the contrast between light and dark in an image by darkening the image and then highlighting the vertical edges. You can apply the Find Vertical edges effect by choosing Effects  Edge Effects  Find Vertical.

The High Pass effect emphasizes color transitions between highlight and shadow colors. You can use it with other imaging operations to create or enhance special effects such as embossing or line-drawing effects. The High Pass effect preserves the contrast of edges and areas of high detail while leaving the rest of the image a neutral gray. You can access the High Pass dialog box by choosing Effects  Edge Effects  High Pass.

The High Pass dialog box contains the following controls:

• Desaturate — removes all color, leaving a gray result. The results of the High Pass effect are close to monochrome, even when this check box is unmarked. You can mark this check box, however, to prevent subtle color shifts that can occur when sharpening is applied to an image. This option works by removing any color artifacts that remain after sharpening.

The Trace Contour effect traces a series of single-pixel lines around areas of contrast and turns the remaining pixels white. You can apply the Trace Contour effect by choosing Effects  Edge Effects  Trace Contour.