Operation Manual

540 | Corel DESIGNER X7 User Guide
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Save the ink settings Click Save. Choose the disk and folder where you want to save the
file, and type a filename in the File name box.
Specify how overprint colors display Click the Overprint tab, and enable the Use overprint check box.
Double-click the color you want to edit, and choose a new color.
You can load preset ink colors by clicking Load, locating the file in which the ink settings are stored, and double-clicking the filename.
Changing bitmaps to the paletted color mode
The paletted color mode, also called indexed color mode, is sometimes used for images on the World Wide Web. When you convert an
image to the paletted color mode, a fixed color value is assigned to each pixel. These values are stored in a compact color table, or palette,
containing up to 256 colors. As a result, the paletted color mode image contains less data than a 24-bit color mode image, and it has a
smaller file size. Conversion to paletted color mode works best on images that have a limited range of colors.
Choosing, editing, and saving a color palette
When you change an image to the paletted color mode, you can use a predefined palette, or you can customize a color palette by replacing
individual colors.
Saving conversion settings
After you choose a color palette and set the dithering and range sensitivity for changing an image to the paletted color mode, you can save
the settings as a conversion preset that you can use with other images. You can add as many conversion presets as you want.
The color palette you use is called the processed color palette. It can be saved for use with other images.
For more information about the predefined color palettes available for the paletted color mode, see “Palette types” on page 540. For more
information about creating and opening custom color palettes, see “Creating and editing custom color palettes” on page 294.
Dithering
Changing images to the paletted color mode lets you use dithering to enhance color information. Dithering places pixels with specific colors
or values relative to other pixels of a specific color. The relationship of one colored pixel to another creates the appearance of additional
colors that do not exist in the color palette.
You can use two types of dithering: ordered dithering and error diffusion. Ordered dithering approximates color blends using fixed dot
patterns; as a result, solid colors are emphasized and edges appear harder. Error diffusion scatters pixels irregularly, making edges and colors
softer. Jarvis, Stucki, and Floyd-Steinberg are conversion options that provide error diffusion.
The Ordered dithering option applies more quickly than the error diffusion options (Jarvis, Stucki, and Floyd-Steinberg) but is less accurate.
Specifying a range-sensitivity color
You can change an image to the paletted color mode and specify a focus color and a range sensitivity for the focus color, so that the focus
color and colors that fall within the range settings are included in the processed color palette. You can also specify how much emphasis to
place on the range sensitivity. Because the palette has a maximum of 256 colors, emphasizing a focus color reduces the number of colors
that fall outside the range sensitivity.
Palette types
The table below outlines available palette types.
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