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Re: CSS Opacity

From: Daniel Beardsmore <public@telcontar.net>
Date: Sun, 29 Apr 2007 04:45:15 +0100
Message-ID: <463414CB.30106@telcontar.net>
To: www-style@w3.org

David Hyatt wrote:
>> You can already either use transparent background images or rgba colors 
>> for the background ...

Ah, thanks. Interesting.

Patrick H. Lauke wrote:
> The one case I could think of is if you defined a solid image as 
> background (i.e. without any encoded alpha channel), and then wanted to 
> use CSS to set its opacity.

Yes, this is what I tried to do. I suppose that now that IE 7 supports RGBA PNG, 
there is no excuse for CSS to work around it. My only objection is that PNG 
isn't very efficient on continuous-tone images and the alpha channel bloats the 
format more. (The Web image formats leave so much to be desired. Imagine, for 
example, if you could assign multiple GIF image colours to varying transparency 
levels to get, say, 250 colours plus alpha in a mere 8 bpp for logo edge 
anti-aliasing? Or DCT lossless alpha channels on JPEGs, or all sorts :)
Received on Sunday, 29 April 2007 03:46:56 GMT

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