>
> I once asked Johathan Sachs (author of Picture Window) what he thought
> about step-wise resizing. He said that if step-wise resizing did a
> better job than doing it all in one go the author of the resizing
> algorithm in use didn't understand how to properly implement the algorithm.
>
All due respect to Mr. Sachs, but this isn't entirely true. There are times
when a 2-3 step resizing is desirable. But to do so, you need to use very
odd percentages, making sure that you don't repeat any multiple of
previously use stepsize. This helps break up the sawtooth edges.
Oh, when downsizing, do not sharpen first. Otherwise you'll end up with
aliasing artifacts. In fact, when downsizing something that has repeating
patterns and you get nasties, apply a gaussian blur to the image equal to
the ratio of pixel reduction. For example, if downsizing by 50%, then blur
2-pixels. Downsizing to 25% of original? 3-pixel blur is required.
AG
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