Pixel density revisited

Started Oct 22, 2008 | Discussions thread
alanr0 Senior Member • Posts: 2,164
Lanczos resampling?

DSPographer wrote:

I never tested Photoshop's resize. It's disappointing that it doesn't
properly filter first. I wonder what the bicubic smoother in the
newer versions does? Your technique of first applying a Gaussian blur
is much better than no filter but we should be able to do still
better than that. Since the Fourier transform of a Gaussian is also a
Gaussian the result has droop in the pass band while still retaining
some energy that will alias. I think the filter window should look
more like a sinc function in the vertical and horizontal directions.

Something like Lanczos resampling perhaps?
http://en.wikipedia.org/wiki/Lanczos_resampling

There is a list of software known to use this lower down the Wiki page (XnView, Irfanview, Gimp, Faststone etc.).

Cheers.
--
Alan Robinson

Post (hide subjects) Posted by
igb
igb
igb
igb
igb
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow