Working with colors in bitmaps

CorelDRAW lets you change colors in monochrome images, apply PostScript halftone screens to optimize color and black-and-white bitmaps for printing, hide and show colors, and mask colors. Monochrome bitmaps have two colors: black and white. You can replace the black and white pixels with any color on a color palette.

If you plan to print to a PostScript printer, you can optimize color or black-and-white printing by applying a halftone screen to an image. Halftone screens break down an image into small dots or lines for clearer printing, continuous tones, and special effects. However, you can see the effect of the screen on the bitmap only after you print it on a PostScript printer. For information about making changes to halftone screens, see “To customize a halftone screen.”

You can hide and display selected colors by masking them. Hiding colors in a bitmap lets objects or backgrounds show through the image. Hiding a color can also alter the apparent shape of a bitmap. For example, if a bitmap shows a person on a black background, you can hide the background so that the bitmap appears to take on the shape of the person rather than a rectangular shape. Also, hiding colors in bitmaps can increase the speed at which objects are rendered on the screen. You can also display certain colors in a bitmap to change the appearance of the image or to see where a particular color has been applied. You can mask as many as 10 colors in a bitmap.

Color masking also lets you change selected colors without altering the other colors in an image. You can also save a bitmap color mask to a file and open the file for future use.


To color a monochrome bitmap

CorelDRAW btnbacktotop Working with colors in bitmaps
1.
 
Select a bitmap by using the Pick tool CorelDRAW pgx pick tool Working with colors in bitmaps.
2.
 
Right-click a color on the color palette to change the color of the foreground (black) pixels.
3.
 
Click a color on the color palette to change the color of the background (white) pixels.

To apply a screen to a bitmap

CorelDRAW btnbacktotop Working with colors in bitmaps
1.
 
Select a bitmap by using the Pick tool CorelDRAW pgx pick tool Working with colors in bitmaps.
2.
 
In the toolbox, click the Uniform fill button CorelDRAW pgx fill color dialog Working with colors in bitmaps.
3.
 
Click the Palettes tab.
4.
 
Choose a fixed palette from the Palette list box.
5.
 
Click Options and click PostScript options.
6.
 
Choose an option from the Type list to set the dot shape or line type.
7.
 
Type a value in the Frequency box to set the number of dots or lines that appear in each inch of the screen.
8.
 
Type a value in the Angle box to set the angle of the dots or lines that appear on the screen.

To hide or display a color in a bitmap

CorelDRAW btnbacktotop Working with colors in bitmaps
1.
 
Select the bitmap by using the Pick tool CorelDRAW pgx pick tool Working with colors in bitmaps.
2.
 
Click Bitmaps CorelDRAW onestep Working with colors in bitmaps Bitmap color mask.
3.
 
Enable one of the following options:
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Hide colors
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Show colors
4.
 
Enable the check box next to the channel that you want to hide or display.
5.
 
Move the Tolerance slider to set the color tolerance for the color.
6.
 
Click the Color selector button CorelDRAW pgx eyedropper tool Working with colors in bitmaps.
7.
 
Click the color that you want to hide or display.
8.
 
Click Apply.

CorelDRAW note Working with colors in bitmaps

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Higher tolerance levels target a broader range of colors around the color you select. For example, if you select baby blue and increase the tolerance, CorelDRAW hides or displays such colors as pastel blue or electric blue.

To open a bitmap color mask

CorelDRAW btnbacktotop Working with colors in bitmaps
1.
 
Click Bitmaps CorelDRAW onestep Working with colors in bitmaps Bitmap color mask.
2.
 
Click the Open mask button CorelDRAW pgx open button Working with colors in bitmaps.
3.
 
Choose the folder where the color mask file is stored.
4.
 
From the Files of type list box, choose a file type.
5.
 
Double-click the file.

CorelDRAW note Working with colors in bitmaps

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Files containing bitmap color mask have the filename extension .ini.

To change a masked color

CorelDRAW btnbacktotop Working with colors in bitmaps
1.
 
Click Bitmaps CorelDRAW onestep Working with colors in bitmaps Bitmap color mask.
2.
 
Choose a color from the list of masked colors.
3.
 
Click the Edit color button CorelDRAW pgx edit color button Working with colors in bitmaps.
4.
 
Use the controls in the Select color dialog box to edit the color.

You can also
Save a bitmap color mask
Click the Save mask button CorelDRAW pgx save button Working with colors in bitmaps. Choose the folder where you want to save the current color mask. Type a name for the file in the File name list box. Click Save.

CorelDRAW tip Working with colors in bitmaps

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You can also change a masked color by clicking the Color selector button CorelDRAW pgx eyedropper tool Working with colors in bitmaps, selecting another color from the bitmap, and clicking Apply.

Working with colors in bitmaps