On 8/7/07, Geert Jordaens <[EMAIL PROTECTED]> wrote:
> I can't seem to find the associated bug. Does anybody know which is the
> bug report?
> I've got a test version (for scale-funcs.c) that scales down in reducing
> the image 1/4 each step.
> Between each step a the image is blurred before starting the next reduce
> cycle.
> The final step performs a bilinear interpolation.
>
> 1000 x 1000 => blur (3x3 gauss) => 500 x 500 => blur (3x3 gauss) =>
> 250x250 => bilinear interpolation => 200x200

I don't understand why you gauss-blur 3x3. won't this percolate
roughly .3 of each pixel into it's neighbours (in terms of the scaled
down result), and thus, isn't this an aesthetic choice rather than a
technical one?
Trying it out myself  it makes things look too blurry. It's great for
simple antialiasing enhancement, but it tends to damage detail. Doing
it without the blur IMO looks better, proportionate to the amount of
detail in the original.

BTW: the current algorithym you implemented has the following problems:
 * Layers with alpha are treated improperly -- the resultant alpha
channel tends to be completely wrong.
 * Layers where width is not even, become skewed to 45 degrees after scaling.

If you would replace the gauss+downscale with just downscaling, that
would be good. Why do you use the gaussian blur?
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