User Guide
Table Of Contents
CHAPTER 4. IMAGE 36
A good alternative to transparency dithering is the Rightclick>
Filters> Colors> Semi-Flatten function.
Additional Information
Default Keyboard Shortcut:
Alt
I
4.9 Image operations with lookuptables
4.9.1 Desaturate
Desaturate is used for removing color from the current selection. If no selection is
made, color is removed from the entirety of the current layer. The result of desaturation
is similar toConvert to Grayscale, but it does not change the image mode to grayscale
and can be performed on a single selection or layer.
4.9.2 Invert
The Invert function converts every color in the selection to its opposite. For example,
black becomes white, yellow becomes blue, etc. The result of this operation is similar
to a photographic negative of the original image. You can see what the opposite of all
colors is by looking at the GTK color selector (double-click the foreground or background
color, and select the GTK tab). The opposite color is the one at the opposite side of the
color wheel.
If no selection is made, the entire layer is inverted.
4.9.3 Equalize
This functions equalizes either the whole contents of an image or the area specified by
a selection. It operates on a histogram of the images. An equalized image has a uniform
distribution of intensity levels. That is, it has about the same amount of dark pixels as
light pixels. Equalization means taking an image and making it have such properties.
The result will be an image whose intensity histogram is almost flat.
4.10 Canvas operations
4.10.1 Offset
Offset moves the current layer or channel up, down, left, or right by the chosen number
of pixels. When the edges overrun the dimensions of the layer, you can decide if they
are wrapped or not. Offset can be used to place layers or floating selections at a specific
position in the image.
Offset is useful if you want to move layers a very exact amount or if you’d like to
move them without extending the layer border. The other important application of this
command is to create seamless tiles for patterns.