Adobe photoshop elements User Manual
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ADOBE PHOTOSHOP ELEMENTS
User Guide
the optimized image. Use hard-edged trans-
parency when you don’t know the background
color of a Web page or when the Web page
background is a pattern. However, keep in mind
that hard-edged transparency can cause jagged
edges in the image.
parency when you don’t know the background
color of a Web page or when the Web page
background is a pattern. However, keep in mind
that hard-edged transparency can cause jagged
edges in the image.
GIF with hard-edged transparency, and displayed in
browser (inset at 300% magnification)
browser (inset at 300% magnification)
To create hard-edged transparency in a GIF or PNG-8:
1
Open or create an image that contains
transparency, and choose File > Save for Web.
2
In the Save For Web dialog box, select GIF or
PNG-8 as the optimization format.
3
Select Transparency.
4
Select None from the Matte pop-up menu to
make all pixels with greater than 50% trans-
parency fully transparent, and all pixels with 50%
or less transparency fully opaque.
parency fully transparent, and all pixels with 50%
or less transparency fully opaque.
Creating background matting in JPEG
images
images
When creating a JPEG from an original image that
contains layer transparency, you must matte the
image against a matte color. Since the JPEG format
does not support transparency, blending with a
matte color is the only way to create the
contains layer transparency, you must matte the
image against a matte color. Since the JPEG format
does not support transparency, blending with a
matte color is the only way to create the
appearance of background transparency in a
JPEG. Fully transparent pixels are filled with the
matte color, and partially transparent pixels are
blended with the matte color. When the JPEG is
placed on a Web page with a background that
matches the matte color, the image appears to
blend with the Web page background.
JPEG. Fully transparent pixels are filled with the
matte color, and partially transparent pixels are
blended with the matte color. When the JPEG is
placed on a Web page with a background that
matches the matte color, the image appears to
blend with the Web page background.
To create a matted JPEG image:
1
Open or create an image that contains
transparency, and choose File > Save for Web.
2
In the Save For Web dialog box, select JPEG as
the optimization format.
3
Select a color from the Matte pop-up menu:
None, Eyedropper (to use the color in the
eyedropper sample box), White, Black, or Other
(to select a color using the color picker).
eyedropper sample box), White, Black, or Other
(to select a color using the color picker).
Note: When you select None, white is used as the
matte color.
matte color.
Previewing and controlling
dithering
dithering
Most images viewed on the Web are created using
24-bit color displays (millions of colors mode),
but many Web browsers are used on computers
using only 8-bit color displays (256-color mode),
so that Web images often contain colors not
available to many Web browsers. Computers use a
technique called dithering to simulate colors not
available in the color display system. Dithering
creates adjacent pixels of different colors to give
24-bit color displays (millions of colors mode),
but many Web browsers are used on computers
using only 8-bit color displays (256-color mode),
so that Web images often contain colors not
available to many Web browsers. Computers use a
technique called dithering to simulate colors not
available in the color display system. Dithering
creates adjacent pixels of different colors to give