I’m having trouble with the image quality of the thumbnails
attachment_fu is creating in my app and I’m hoping someone can point
me in the direction of a fix.
In my search for answers I’ve found this page  which claims
“ImageMagick’s default resampling filter used for image resizing is
the Lanczos filter. For Image Science it’s bilinear filter. Bilinear
is faster but it’s not the best for creating thumbnails of
photographic images. It’s only possible to set Lanczos as the default
by patching FreeImage source. It’s pretty straightforward though …”
However there is no detail on how to patch free image. In any case
another page  claims image science has since been updated and that
it now uses the “Catmull-Rom spline filter for better quality”. Yet,
the thumbnails still look poor to me.
I’m using version 1.1.3 of image_science and, as far as I can tell,
the latest version of attachment_fu. If anyone does know of a fix or
has any info on this it would be much appreciated.