On Sun, 2015-04-19 at 01:26 +0200, renat wrote: > > scanned images are going pixelated > Faced the very same (or similar?) problem while trying to resize > photos made by > digital camera. Very similar "grids" appear on nearly-flat surfaces > with a bit > of noise (like on sky). Surprisingly, faced the very same grids not > only in > GIMP, but in some other programs as well (in Image Viewer in Ubuntu > 14.04, for > example), so there may be a problem with underlying library (GTK?), > not with > GIMP itself. > Here is an full-size example image: > https://drive.google.com/file/d/0B2nZFc31UFnoNUVTcGpoUHFSbm8/view?usp=sharing > And it's resize (width 1920 px) - grid is easily visible: > https://drive.google.com/file/d/0B2nZFc31UFnoT1ZvM0xxQW8xSU0/view?usp=sharing
Yes, there;s a Moiré pattern in the resized image. How was the image created exactly? It looks like you photographed a printed image and then used rawtherapee to convert to a jpeg for gimp to open?? If so, the low frequency grid is from the four-colour print process. I see this pattern in gimp scaling with linear but not with cubic -- see Tool Options. Liam > Tests were performend with gimp 2.8.10-0ubuntu1 on Ubuntu 14.04, and > with gimp > 2.8.14 on Windows 7 Home. > > Attachments: > * > http://www.gimpusers.com/system/attachments/195/original/gimp-ubuntu-scaled.png > _______________________________________________ gimp-user-list mailing list List address: [email protected] List membership: https://mail.gnome.org/mailman/listinfo/gimp-user-list List archives: https://mail.gnome.org/archives/gimp-user-list
