Use the Edge effects to clarify your image and to accentuate the edges and contrast areas in your image.
Important: These commands work on greyscale and 16 million color images only. To increase the color depth of an image, see Increasing the Color Depth of an Image.
To apply an edge effect:
To limit the edge effect to a specific area, make a selection in the image. See Using the Selection Tools.
Choose Effects > Edge Effects, then choose a command.
Dilate Enhances the light areas of the image.
Enhance and Enhance More Increases the contrast along the edges in the image.
Erode Applies a stronger contrast to the edges of the image.
Find All Enhances the contrasts between light and dark in the image by darkening the image and then highlighting the edges.
Find Horizontal Enhances the horizontal edges in the image using the same method as the Find All command.
Find Vertical Enhances the vertical edges in the image using the same method as the Find All command.
Trace Contour Traces a series of single-pixel lines around the areas of contrast and turns the pixels white.