Adobe ADBCD17648MC 사용자 설명서

USING PHOTOSHOP ELEMENTS 8
Optimizing for the web

Transparency makes it possible to create nonrectangular images for the web. Background transparency, supported by 
the GIF and PNG formats, preserves transparent pixels in the image and allows the background of the web page to 
show through the transparent areas of your image. (Although the JPEG format does not support transparency, you can 
specify a matte color to simulate the appearance of transparency in the original image.) 

Background matting, supported by the GIF, PNG, and JPEG formats, simulates transparency by filling or blending 
transparent pixels with a matte color that matches the web page background. Background matting works best if the 
web page background is a solid color and if you know what that color is.

To create background transparency or background matting in the optimized image, you must start with an image that 
contains transparency. You can create transparency when you create a new layer or use the Background Eraser, Magic 
Eraser, or Magic Extractor tools.

When working with GIF or PNG-8 files, you can use a matte setting of None to create hard-edged transparency: all 
pixels that are more than 50% transparent in the original image are fully transparent 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 transparency can cause jagged edges in the image.