> Why would you first mosaic it before resizing it?  Isn't resampling
enough?
>
When I just resize the image, only every 2nd Pixel(in x and y) would be
taken in the resulting image ...
this would lead to aliasing-artifacts ... we would get our nice
stairsteps...

If you apply first a 2x2-Mosaic-Filter to the image the four pixels would be
averaged, and you can lessen the aliasing ...
You can prove that if you do the following:
Take one picture, and resize it to 50%
Then take another image, apply the mosaic and then resize the image.

Now create a difference-picture of the both ...
Probably you will see everything black now, but if you take the time, to
adjust the brightness/contrast you will see,that there are differences
(especially on sharp corners) between the pictures ...
First move the brightness until the black parts are at 49%White, then raise
the contrast ...

OK ... Maybe better programs like Photoshop (or photoshop-class-programs) to
this automatically, but I prefer to do this myself ... I don't simply trust
the smart-resize-option ...

OK ... so far ..

--
Jan Walzer <jan### [at] lzernet>

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