SAMPLING FILTER comparison | Fusion, GraphicsMagick, ImageJ, Photoshop, XnView

[Rainer M. Engel]

Hello everyone,

I made a filter comparison concerning some imaging software and also
ImageJ. Some things seems to be interesting here I think.

Sampling-Filter Comparison:
http://dl.dropbox.com/u/414433/imagej/sf_comparison_v02.jpg

01.
ImageJ and XnView reduce an image towards the Cartesian origin, whereas
other tools accomplish this towards the image center. It looks like that
but it is just a different approach getting visible here.

02. (This one is nice :-)
Having a look at ImageJ and Fusion one can see a filter effect which
shows faded scene elements like an overlay. With ImageJ Bilinear (with
Average Option) one gets this. I used movie scenes with a camera pan or
constant dolly movement.
Interesting is that this effect plots out elements of its source frames
and I wonder why other tools don't do this with their filters and if
it's generally useful why is there no option to en- or disable this?

03.
I don't understand why no filtering (none) looks very similar to
Bilinear speaking for ImageJ.


Any thoughts about it are most welcome.


regards,
Rainer


--
Rainer M. Engel
www.scientific-media.de