| 5.5. 亮度-对比度 | ||
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5. Color Tools |  |
| 5.5. 亮度-对比度 | ||
|---|---|---|
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5. Color Tools | |
The Brightness-Contrast tool adjusts the brightness and contrast levels for the active layer or selection. This tool is easy to use, but relatively unsophisticated. The Levels and Curve tools allow you to make the same types of adjustments, but also give you the ability to treat bright colors differently from darker colors. Generally speaking, the BC tool is great for doing a "quick and dirty" adjustment in a few seconds, but if the image is important and you want it to look as good as possible, you will use one of the other tools.
In GIMP 2.4, a new way of operating this tool has been added: by clicking the mouse inside the image, and dragging while keeping the left mouse button down. Moving the mouse vertically changes the brightness; moving horizontally changes the contrast. When you are satisfied with the result, you can either press the OK button on the dialog, or hit the Return key on your keyboard.
You can get to the Brightness-Contrast tool in two ways:
In the image-menu through: → → or → ,
by clicking the tool icon:
in Toolbox, provided that you have installed color tools in Toolbox.
For this, please refer to 第 1.7 节 “Toolbox”.
You can save the color settings of your image by clicking the
button
The
button opens a menu:
which lets you Import Settings from File or Export Settings to File, and gives you access to the Manage Save Settings dialog:
This slider sets a negative (to darken) or positive (to brighten) value for the brightness, decreasing or increasing bright tones.
This slider sets a negative (to decrease) or positive (to increase) value for the contrast.
To make your work easier, this button lets you turn to the Levels tool with the same settings.
The Preview checkbox enables the rendering of all changes to the brightness and contrast on the canvas for immediate evaluation.
