Autodesk 00126-050008-1630A User Guide - Page 78

WiseImage – User’s Guide

80

Changing the gamma curve

There are three interrelated methods of changing the shape of the Master gamma

curve and the curves for individual channels.

1.

Select or clear the

S-Curve

checkbox. S-curve is a form of a gamma curve

that is always symmetrical around the central point of a distribution range.

This implies that when adding brightness to dark areas we automatically

darken bright areas to the same extent creating a more balanced

brightness for the human eye. If the

S-Curve

checkbox is off a gamma

curve can be created by shifting the overall balance of brightness in the

resulting image.

2.

Enter a value in the

Gamma

box. This changes the curve slope.

3.

Drag the

Master

curve or the curves for individual channels in the

histogram window.

When

Master

is selected in the

Channel

list, all the curves are shown (at first you

see them as a single white curve since the curves for color channels overlay).

When placing the mouse pointer over the curve a bold point will be seen that can be

dragged to change the shape of the curve. While keeping the mouse pointer over

the curve, the real distribution of color brightness on the image can be seen.

To change the shape of the curves for the Red, Blue or Green channels, select the

corresponding color name from the

Channel

list.

For some images the Master curve Red, Blue or Green components can also be

split by pressing the

Auto Set

button

.

Modifying a Color Palette

The editing operations allow the color palette to be calculated automatically or

modified based on the user-defined colors.

Manage the colors in the image using the

Color Classifier

dialog of the

rImage

menu. The following operations are available:

•

Reducing the palette by deleting the selected color or colors or by

merging several colors into one;

•

Changing selected colors;

•

Adding new color(s) to the palette; and

•

Saving the palette for further use when processing a set of similar color

images.

To edit a palette

Choose

Color Classifier

from the

rImage

menu or click the

button on the

WiseImage

toolbar.

The buttons and controls in the

Image Classifier

dialog

Colour samples table

This table contains color samples of the current palette.

Colour counter

This control is used to show the number of colors in the

current palette (from 2 to 256).

Autodesk 00126-050008-1630A User Guide - Page 78

Modifying a Color Palette

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