On 8/15/2011 9:44 AM, Charles Wilson wrote:
On 8/15/2011 10:33 AM, Warren Young wrote:
The hard edges in the original art are causing stair-stepping when doing
a direct downsample, though. (Look at the pointy bits.) By blurring
the high-res version and then downsampling by a non-integral amount, you
can get a much smoother result.
This is only the case if the "downsample" operation used by GIMP, when
d/s by an integral amount, is to simply pick every Nth pixel. That's
very fast -- but is not the correct operation (I'd posit a GIMP bug, in
fact).
Perhaps Gimp did that in the past, but what you're describing is now
Gimp's "None" interpolation mode. Both it and Photoshop have better
resampling modes, but they all give some stair-stepping with hard
diagonal lines if you don't give it a bit of help.
