Gimp quality problem when I curve an image

[SO•Yukine]

Hello, I have a quality problem when I curve an image, anyone can help me?

Pic link: http://image.noelshack.com/fichiers/2013...-21-23.png

[SO•Audiojack]

I can't see a problem here.

[SO•Yukine]

Look the grill and light, the upper part is pixelized.

[Iceman]

I guess thats normal. Photoshop does the same thing.

[SO•Audiojack]

That's what the program does. The algorithm for bending an image works like that, it must multiply pixels at some places to make it look stretched and subtract some in the places where they don't fit anymore. This will cause some aliasing in the final result.

My advice is to try and sliiightly blur the aliased parts (not around them) to make it kind of a "pseudo-antialiasing" OR just re-do the lines by hand, which may also help. I use both methods in my skins, but usually I just try to avoid unnecessary curving and cut and stretch little pieces instead and then put them back together for a final result.

[[TC]»Pete«]

Because the original image is not a vector, rasterisation techniques cannot be applied to that image therefore you will run into the problems you've mentioned.

You could try converting the original image to a vector graphic then bring that into GIMP and try again though I'm not sure how GIMP handles vector graphics.

[SO•Yukine]

Thanks for help!

[[TC]»Elmo«]

If you can, do the curve transformations at a much higher resolution, then downscale it afterwards rather than before. That should at least reduce the effect.