On Mon, Dec 08, 2003 at 06:13:47PM -0500, Bob Lockie wrote:
> On 12/08/03 16:57 Marco Wessel spoke thusly<br>
> >On Mon, Dec 08, 2003 at 04:43:43PM -0500, Bob Lockie wrote:
> >
> >>KSnapshot: 34 108 bytes, 585x385, 24bbp, RGB, deflate.
> >>Gimp: 78 896 bytes, 400x263, 24bbp, RGB, deflate, compression 9.
> >>
> >>There are no options in KSnapshot so I don't know what the compression 
> >>level is (can it be higher than the highest in Gimp=9?).
> The pics are on the web at:
> http://www.lockie.ca/test/ksnapshot.png
> http://www.lockie.ca/test/gimp.png

As Marco speculated earlier (and you cut out):

> Anyway, if no one has said it yet, this is most probably caused by you
> scaling the image with resampling turned on. This makes images less easy
> to compress when using the types of compression that PNG and such use.

That's exactly what is happening. Zoom in on your gimp.png and you'll see
shades of gray around your letters. Since there's more color variance in
your scaled down picture, there's less common information to compress with,
so the picture is larger.

You can try setting the interpolation type to None, which will simply throw
out data instead of trying to interpolate the pixel data, but the results
are pretty poor. You do get a smaller file size though.

I will note, that loading ksnapshot.png and saving it in the GIMP (without
scaling) results in a smaller file size, so KSnapshot isn't doing as well
as it could. ;)

in a smaller
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