Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Mail Systems
Eclipse Documentation

How To Guides
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Problem Solutions
Privacy Policy




Grokking The Gimp
Previous Page Home Next Page

Feathering is a selection edge treatment similar to antialiasing. It works by changing the alpha value of pixels as a function of their radial distance from the selection edge. Figure  3.13

Figure 3.13: The Effect of Feathering
Figure 3.13

illustrates an example of a feathered selection. Figure  3.13(a) shows how two guides have been placed to aid in framing a selection using the Ellipse Select tool.

As shown in Figure  3.13(b), a value of 40 has been chosen for the Feather Radius in the Tool Options dialog for this selection tool. Furthermore, Antialiasing has been turned off. The result of inverting the selection and cutting away the background is shown in Figure  3.13(c). This result is actually displayed on a yellow background so that the transparency of the flower pixels can be better seen. Also, superimposed on Figure  3.13(c) is the original elliptical selection.

The transparency of the flower image shown in Figure  3.13(c) is 50% at the selection edge. The transparency increases moving outward from the edge and decreases moving inward from it. The rate at which the transparency changes while moving away from the selection edge is determined by the Feather Radius. For this example, the value chosen is 40, meaning that there is a feathering effect up to 40 pixels away in both directions from the selection edge. Note that for all the selection tools, feathering is off by default.

Partially selected pixels are discussed again in Section  4.1.7.

Grokking The Gimp
Previous Page Home Next Page

  Published under the terms of the Open Publication License Design by Interspire