Re[2]: style sheet scalability (was: Specifying style notati
Tue, 05 Dec 95 14:57:28 EST

I have had luck with the idea that pixels form in groups of 4. and
therefore it might make sense to only change image size in groups of 4
as well. For instance, if you scan in at 72, then changing image size
to 144 would result in a better looking image than say resizing at
143. Keeping this in mind, I have been able to achieve smoother
looking graphics.

______________________________ Reply Separator _________________________________
Subject: Re: style sheet scalability (was: Specifying style notation
Author: at interport
Date: 12/5/95 2:19 PM

>> Legibility should normally be increased with a larger display area,
>> assuming you don't get make the image too big for your display ;), as
>> long as the number of pixels you use on your screen is an integral
>> multiple of the number in the bitmap.

This would work although it would still be a bit rough. It would look far
better than if the enlargment is *not* a multiple of the bitmap.

>OK. I'm confused here. It has been my experience that if you blow up
>a GIF image too much, the image loses quality due to the face that
>the image is a bunch of pixels being drawn absolutly. Text gets
>"jaggies" quickly under this scenario. That is why Postscript
>uses algorythms to scale text larger instead of just blowing up
>the pixels. I would assume that this would be true for many other
>image types as well. Highly ditherable but not already dithered
>images would benefit from being blown up better than others, but
>images that the designer dithers suffer from scaling problems.

Sure - postscript is a great fix to the 'jaggies' but there are other
methods of getting rid of 'em -- Photoshop is a great example of how to
enlarge and smooth at the same time. Anti-alias it! PS can use several
different schemes to "smooth" images and they all look pretty good. What
about a built in anti-aliaser? Dithering doesn't do much with how the
edges look -- it's a method for reducing colors or using fewer colors to
approximate a graident (or more colors than are present).

>Can you explain "how" legibility increases with significant size

If using a bitmap it won't -- it will only appear to be smoother with
significant size enlargments of a multiple of the bitmap size... Whew, say
that five times fast! ;)

=B-) Jacob Cazzell

|Jacob Cazzell                       | My name is Ozymandias, king of | 
|             | kings:  Look on my works, ye   | 
| | mighty, and despair!           |