Adobe ILLUSTRATOR 10 - Using Help | Contents | Index Back; Working with Bitmap Images

Using Help | Contents | Index Back 237
Adobe Illustrator Help Working with Bitmap Images
Using Help | Contents | Index Back 237
Wo r king with Bitmap Images
About working with bitmap images
You can do the following with bitmap images:
• Place an image into a file. (See “Placing files” on page 35.)
• Use the Links palette to see information about the image. (See “Managing linked and
embedded images” on page 37.)
• Trace images using the auto trace tool. (See “Tracing artwork” on page 89.)
• Create bitmap artwork with a transparent background using the Rasterize filter. By
using the Transparent option in the Rasterize filter, you create an alpha channel (as in
the Adobe Photoshop application). The transparent background also provides superior
anti-aliasing of the rasterized artwork than does using a clipping mask to mask the
background.
• Create a clipping mask in the Rasterize filter to make the background appear trans-
parent. (See “
Working with clipping masks” on page 149.)
• Use the Rasterize dialog box to convert vector objects (including paths and text
objects) into an image, and choose other options for the image. You can also change
the color model for the image by reselecting Rasterize and changing the color.
(See “
Changing vector graphics into bitmap images” on page 237.)
• Colorize 1-bit images. (See “Colorizing 1-bit images” on page 238.)
• Use bitmap filters and filter effects. (See “Choosing a filter or filter effect” on page 242.)
• Use the Object Mosaic filter to convert the pixels to a collection of colored squares.
Then you can use Illustrator tools. (See “
Using the Object Mosaic filter” on page 247.)
• Apply the Photo Crosshatch filter, which gives a photographic image the appearance of
a pen drawing. (See “
Using the Photo Crosshatch filter” on page 248.)
Changing vector graphics into bitmap images
The process of changing a vector graphic to a bitmap image is called rasterization. During
rasterization, Illustrator converts the graphic’s paths into pixels. The rasterization options
you set determine the size and other characteristics of the resulting pixels.
There are two ways to rasterize vector graphics:
• The Object > Rasterize command permanently converts the graphic to a bitmap image
using the specified rasterization settings. Once you apply the Object > Rasterize
command, you cannot modify the image’s rasterization settings.
• The Effect > Rasterize command changes only the appearance of the graphic without
changing the graphic’s underlying structure. You can modify the rasterization settings
of the bitmap image or revert the bitmap image to a vector graphic at any time.