Info

Embossing kernels are:

The first operator makes an image that appears to be illuminated from above (north), the second from the left (west), and the third from the upper left (northwest). Eight basic embossing operators exist.

For special-purpose image displays, it's easy to create linear combinations and kernels in larger sizes:

-2 -5 -4 -1 0 -5 -10 -4 2 1 -4 -4 8 12 4 • -1 2 12 14 5 _0 1 4 5 2_

Larger sizes offer greater immunity to noise than small kernels, and may be worth pursuing on those special occasions when an unusual type of detail must be teased from an image.

It is important to remember that the initial output for a bas-relief or embossing operation may have a very small range of pixel values, especially if the source image is low in contrast. Do not be surprised if you must perform a linear brightness scaling before you can see the result.

14.2.4.2 Sobel, Kirsch, and Prewitt Operators

A number of engineers and scientists have described schemes for detecting features in images, most notably the sudden brightness changes that occur at their boundaries and edges. Among the three best known edge operators are those of Sobel, Kirsch, and Prewitt. Their kernels are:

Was this article helpful?

0 0
Telescopes Mastery

Telescopes Mastery

Through this ebook, you are going to learn what you will need to know all about the telescopes that can provide a fun and rewarding hobby for you and your family!

Get My Free Ebook


Post a comment