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ADOBE PHOTOSHOP ELEMENTS 2.0
User Guide
4
For GIF and PNG-8 format, specify how to treat
partially transparent pixels in the original image.
You can blend these pixels with a matte color, or
you can create hard-edged transparency. (See
“Creating background matting in GIF and PNG
images” on page 215, and “Creating hard-edged
transparency in GIF and PNG-8 images” on
page 215.)
Creating background matting in GIF and
PNG images
When you know the background color of the Web
page on which an image will be displayed, you can
use the matting feature to fill or blend transparent
pixels with a matte color that matches the Web
page background.
The results of matting GIF and PNG-8 images
depend on the Transparency option:
•
If you select Transparency, partially transparent
pixels are filled with the matte color, and fully
transparent pixels remain transparent. When
you place the image on a Web page, the edges of
the image blend with the background, which
shows through the fully transparent pixels. This
option prevents the halo effect that results when
you place an anti-aliased image on a Web page
background that differs from the image
background. This option also prevents the
jagged edges of hard-edged transparency.
•
If you deselect Transparency, fully transparent
pixels are filled with the matte color, and
partially transparent pixels are blended with the
matte color.
To create a matted GIF or PNG image:
1
Open or create an image that contains trans-
parency, and choose File > Save for Web.
2
In the Save For Web dialog box, select GIF,
PNG-8, or PNG-24 as the optimization format.
3
For GIF and PNG-8 format, do one of the
following:
•
To keep fully transparent pixels transparent,
and blend partially transparent pixels with the
matte color, select Transparency.
•
To fill transparent pixels with the matte color
and blend partially transparent pixels with the
matte color, deselect Transparency.
4
Select a color from the Matte pop-up menu:
Eyedropper (to use the color in the eyedropper
sample box), White, Black, or Other (to select a
color using the Color Picker).
Creating hard-edged transparency in GIF
and PNG-8 images
When working with GIF or PNG-8 files, you can
create hard-edged transparency. With hard-edge
transparency, all pixels that are more than 50%
transparent in the original image are fully trans-
parent in the optimized image, and all pixels that
are more than 50% opaque in the original image
are fully opaque in the optimized image. Use hard-
edged transparency when you don’t know the
background color of a Web page, or when the Web
page background contains a texture or pattern.
However, keep in mind that hard-edged trans-
parency can cause jagged edges in the image.
