Bug 151408

Summary:	Mitchell scaler shows tiling artifacts
Product:	[Applications] krita	Reporter:	Dik Takken <kde>
Component:	General	Assignee:	Camilla Boemann <cbo>
Status:	RESOLVED FIXED
Severity:	normal	CC:	lambdae2, lemma
Priority:	NOR
Version:	1.6.1
Target Milestone:	---
Platform:	Gentoo Packages
OS:	Linux
Latest Commit:		Version Fixed In:
Attachments:	Sample of scaler artifacts

Description Dik Takken 2007-10-26 22:29:16 UTC

Version:           1.6.3 (using KDE KDE 3.5.7)
Installed from:    Gentoo Packages
OS:                Linux

Just recently, I scaled a 16 MP image using Krita's Mitchell scaler. Next, I applied unsharp masking on the result (radius 1, strength 1.6, threshold 0.0). The final image revealed a grid of discontinuities, produced by the scaler. It is not easy to reproduce this (scaling percentage seems critical) so I attached a small portion of the result.

Comment 1 Dik Takken 2007-10-26 22:30:35 UTC

Created attachment 21917 [details]
Sample of scaler artifacts

Comment 2 Halla Rempt 2007-11-16 16:50:09 UTC

Casper, can you look at this?

Comment 3 Elián Hanisch 2008-10-26 14:37:53 UTC

I have been trying to reproduce this in krita2beta2 and in 1.6.3 without avail, can you provide more information about this bug if it still occurs to you?

Comment 4 Dik Takken 2008-10-26 16:43:16 UTC

I'm still at KDE 3.5 here, as soon as I can move to KDE 4 I'll try Krita again.

Comment 5 Elián Hanisch 2008-10-26 19:06:15 UTC

can you try in 1.6.3? if you get this bug again can you ad more detailed information about how to reproduce it? (attach the image file, the scaling you used, all the steps for get the artifacts)

Comment 6 Camilla Boemann 2009-02-14 15:59:43 UTC

Bug is kind of solved in trunk. But afterwards I've removed the mitchell filter

I've added the Bicubic filter and it is very good

so closing this bug