Bug 159397

Summary: Resize quality is really bad
Product: [Applications] digikam Reporter: Kamil Stepinski <kamil.stepinski>
Component: Plugin-Bqm-GmicAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED FIXED    
Severity: wishlist CC: caulier.gilles
Priority: NOR    
Version: 0.9.2   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed In: 8.4.0
Sentry Crash Report:

Description Kamil Stepinski 2008-03-16 11:36:38 UTC 
Version:           0.9.2 (using KDE 3.5.8)
Installed from:    Ubuntu Packages
OS:                Linux

Guys,

I see the similar report in the most recent bugs (Bug 152192) but as far as I can see you ended up with no conclusion? Was the bug resolved in the next version of digiKam? No statement there...
Well.. Here's how I see things:


The image resizing quality is _really bad_ in digiKam (I have 0.9.2 installed).
It's so bad that the output is just unacceptable for me. :(

I really think you should add a selection box with a few algorithms (Hermite, Mitchell, Lanczos, etc.) with Lanczos as a default one because it provides the best results.
Currently I'm resizing all pictures with IrfanView (runs well under Wine) and the rest of postprocessing is done in digiKam. It's not the most convenient let me tell you...
I think you should consider the current resize quality as a major issue - as it is a tool that is used very frequently.

Here's the link to the example of the resize quality comparison:

http://picasaweb.google.com/kamil.stepinski/Digikam/photo#5178275271094829746

Please observe car window edges.

1 - digiKam 0.9.2 to the left, IrfanView 4.10 to the right
2 - resizing from 5Mpix camera to 800x600, IrfanView is using Lanczos filter, digiKam is using I-don't-know-what.

That's the only major problem I have with digiKam. I think the resize has been working much better in 0.8.x version.

At the end -> Thanks guys for the great piece of software! The application is really great!
Comment 1 caulier.gilles 2008-03-16 11:48:12 UTC 
This bug entry is invalid. Problem have been fixed in 0.9.3 release... Please update !

Gilles Caulier
Comment 2 Achim Bohnet 2008-03-16 18:46:09 UTC 
In case you're using Gutsy you find 0.9.3 pkgs at:

http://www.mpe.mpg.de/~ach/kubuntu/gutsy/Pkgs.php

Have fun,
Achim
Comment 3 caulier.gilles 2024-05-26 09:00:52 UTC 
With next digiKam 8.4.0, a new G'MIC processor tool for the Batch Queue Manager
will be available. The G'MIC scaling filters has the desired options :

Image editor :

https://i.imgur.com/gzUc5KX.png
https://i.imgur.com/6o0CsSN.png

BQM :

https://i.imgur.com/0bQrJk4.png
https://i.imgur.com/xw4VPsa.png

Plenty of other G'MIc tools are also available for your workflow, and
more (in fact over 600 filters to process photo). The settings from an Image
Editor G'MIC-Qt filter can be backported to the BQM using the 'copy' button on
the top of the dialog.

Gilles Caulier