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




10.22.  White Balance

Revision History
Revision $Revision$ 2006-09-11 scb

The White Balance command automatically adjusts the colors of the active layer by stretching the Red, Green and Blue channels separately. To do this, it discards pixel colors at each end of the Red, Green and Blue histograms which are used by only 0.05% of the pixels in the image and stretches the remaining range as much as possible. The result is that pixel colors which occur very infrequently at the outer edges of the histograms (perhaps bits of dust, etc.) do not negatively influence the minimum and maximum values used for stretching the histograms, in comparison with Stretch Contrast. Like “Stretch Contrast”, however, there may be hue shifts in the resulting image. This command operates on layers from RGB images. If the image is Indexed or Grayscale, the menu item is insensitive and grayed out.

10.22.1.  Activating the Command

  • You can access this command from the image menubar through Layer->Colors->Auto->White Balance.

10.22.2.  White Balance” example

Figure 10.92.  Original image

Original image

The active layer and its Red, Green and Blue histograms before “White Balance”.

Figure 10.93.  Image after the command

Image after the command

The active layer and its Red, Green and Blue histograms after “White Balance”. The pixel columns reach the right end of the histogram (255): pure white is created (255, 255, 255).

Histogram stretching creates gaps between the pixel columns, giving it a striped look.

  Published under the terms of the GNU General Public License Design by Interspire