Bug 149744

Summary: FILEIO : add new options to export JPEG files
Product: [Applications] digikam Reporter: Mikolaj Machowski <mikmach>
Component: Plugin-DImg-JPEGAssignee: Digikam Developers <digikam-bugs-null>
Status: CONFIRMED ---    
Severity: wishlist CC: caulier.gilles
Priority: NOR    
Version: 0.9.3   
Target Milestone: ---   
Platform: Compiled Sources   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Mikolaj Machowski 2007-09-10 22:05:28 UTC 
Version:            (using KDE Devel)
Installed from:    Compiled sources
OS:                Linux

Recent discussion on digikam-devel showed that JPEG export isn't so simple as it seems. I think specialised plugin for export to JPEG could be good thing. Such plugin should allow:

- very detailed control of export settings (sampling, quality, etc.)
- preview of effects for interesting details of image
- to view size of image after export

In future even more advanced feature would be interesting: fake zones of compression. Scenario:

1. User selects interesting area and calls plugin
2. Digikam creates two images and user can choose compression and other settings for each image separately.
3. At the end image with selected area is superimposed on image with unselected area.

In this way user can minimize final size of image without losing important details.
Comment 1 André Monteiro 2008-04-15 20:17:55 UTC 
Another interesting feature would be the ability to detect and reuse the original JPG quality settings, like Gimp.
Comment 2 Arnd Baecker 2008-04-15 20:36:31 UTC 
Andre, yes, this would be good, as 
"Trying to improve the appearance of a Jpeg image by re-compressing at a
higher quality setting achieves very little (except an increase in
file-size)." http://photo.net/learn/jpeg/

This was discussed in the (closed) bug
http://bugs.kde.org/show_bug.cgi?id=149578#c15
but never got implemented.