Bug 235601

Summary:	Local contrast tool preview is wrong
Product:	[Applications] digikam	Reporter:	Julien Narboux <Julien>
Component:	Plugin-Editor-LocalContrast	Assignee:	Digikam Developers <digikam-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	caulier.gilles, mailto.mikes, philippe.quaglia
Priority:	NOR
Version:	2.4.0
Target Milestone:	---
Platform:	Ubuntu
OS:	Unspecified
Latest Commit:	http://commits.kde.org/digikam/c7bf359c7e563be57417f302b5846dde01f0169b	Version Fixed In:	2.9.0
Sentry Crash Report:
Attachments:	Sample of the Problem with preview and resulting picture with the local contrast tool. Preview Settings LC

Description Julien Narboux 2010-04-28 08:15:24 UTC

Version:           svn 1.3.0 (using KDE 4.3.5)
Installed from:    Ubuntu Packages

The local contrast plugin preview does not show the same picture as the final. It looks like parameters depend on the size of the picture. Maybe the blur parameter should be expressed as a percentage of the diagonal of the picture.

Julien

Comment 1 caulier.gilles 2011-12-17 19:07:49 UTC

Julien,

This file still valid using digiKam 2.4 ?

Gilles Caulier

Comment 2 Mike 2012-01-03 19:08:57 UTC

Created attachment 67406 [details]
Sample of the Problem with preview and resulting picture with the local contrast tool.

Comment 3 Mike 2012-01-03 19:09:47 UTC

I can affirm the problem still exists in Digikam 2.4 in Oneiric. I had this problem before in Digikam 2.0. After applying the preview settings the finished image is much more enhanced...overenhanced. So the preview makes no sense... what you get is another image... 
I attached a sample of the preview and the resulting picture resized and put in one picture. As you can see : the preview is the above. 
Regards, 
Mike

Comment 4 caulier.gilles 2012-01-03 19:34:04 UTC

Can you share your photo to test in local ?

Thanks in advance

Gilles Caulier

Comment 5 Mike 2012-01-03 19:52:45 UTC

Hi Gillles,

sure. Heres the one screenshot i used for the preview so you can see the settings i used in LC Tool. I will send you the original picture by email because here for the bugtracking system ts to big i assume. 
Thank you very much :-)
Mike

Comment 6 Mike 2012-01-03 19:55:01 UTC

Created attachment 67408 [details]
Preview Settings LC

Comment 7 caulier.gilles 2012-01-17 11:49:13 UTC

*** Bug 291537 has been marked as a duplicate of this bug. ***

Comment 8 Marcel Wiesweg 2012-05-21 16:48:37 UTC

It seems to me that indeed, the "blur" parameter is highly defining for the result in inplace_blur() and func(). But I dont understand the maths enough to judge if linear scaling of the blur parameter when scaling the picture will fix the problem.

Comment 9 caulier.gilles 2012-08-22 16:52:17 UTC

Git commit c7bf359c7e563be57417f302b5846dde01f0169b by Gilles Caulier.
Committed on 22/08/2012 at 18:51.
Pushed by cgilles into branch 'master'.

don't use downscaled image to render preview, it will differs than final rendering
Related: bug 204466

M  +4    -3    imageplugins/enhance/localcontrasttool.cpp

http://commits.kde.org/digikam/c7bf359c7e563be57417f302b5846dde01f0169b