Re: hyper interpolation not working

Dennis wrote:
> 
> I'm not sure what changed on my system =( .. but suddenly the Hyper
> interpolation feature in gqview, and the Cubic interpolation for scaling
> in gimp do not seem to be working.
> 
> Bilinear interpolation in gqview still works.
> 
> I upgraded a whole bunch of packages, but the problem persists.
> 
> gimp 2.0.4
> gqview 1.5.4
> glib 2.4.7
> gdk-pixbuf 0.22.0-r3
>

version of GTK+ ?
(note: as of GTK+ 2, gdk-pixbuf was merged with GTK+)
 
>
> Any idea what else might be preventing interpolation from occuring?
> Zooming works, but no interpolation.


Testing it, I see the same thing with GQview 1.5.4 and GTK+ 2.4.9 - sort of -
looks like a change or bug in GTK+.

What I see is that scaling an image down (zooming to make it smaller) seems to
work - the image is interpolated. But when scaling an image to be larger it is
no different than using nearest pixel scaling - it is doing something though,
the image seems to shift down and right a few pixels (the shift is probably
related to the bug causing no interpolation).

I rarely use the Hyper algorithm, so I am not really familiar with how it is
supposed to work. GQview is still developed on GTK 2.2.4, so this bug is news to
me.


If or when you file this bug with GTK+, the image scaling code attempts to use
some processor specific features (such as mmx), so including your processor
family may be of help to the GTK+ developers [AMD Athlon XP here].


As for the GIMP, I can not comment as I do not know if they use GTK's
interpolation mechanism for scaling images (I would be suprised if they did,
though).


Greetings,
John

-- 
John Ellis <[email protected]>

http://gqview.sourceforge.net <GQview> | http://gqapplets.sourceforge.net
http://gqmpeg.sourceforge.net <GQmpeg> |                  <panel applets>


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