Bug 95495

Summary: filesize reduced after image rotate
Product: [Applications] digikam Reporter: Sunny <sloncho>
Component: Plugin-Editor-RotationAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal    
Priority: NOR    
Version: 0.7.0   
Target Milestone: ---   
Platform: openSUSE   
OS: Linux   
Latest Commit: Version Fixed In: 7.6.0
Sentry Crash Report:

Description Sunny 2004-12-20 02:13:27 UTC 
Version:           0.7-beta1 (using KDE KDE 3.3.2)
Installed from:    SuSE RPMs
OS:                Linux

Hi,
when I open and image in the image viewer, then hit (1) to rotate it and close image viewer, confirming the save operation, the file size of the result is much smaller than the original. I have checked, and the picture size is preserved, but I'm not sure about the resolution and the quality of the picture.

Steps to reproduce:
I open a picture (jpg) 2160x1440 pix, filesize 1,044,877 bytes
Just rotate the picture clockwise and exit the viewer. When it asks to save the picture, I said yes.
Now the new picture is 1440x2160 pix, as expected, but the filesize is only 368,427 bytes?

I would expect the filesize to be approx. the original if there is no reduction in the quality of the picture.

Cheers
Sunny
Comment 1 Renchi Raju 2004-12-20 23:12:36 UTC 
the imageviewer rotation and saving is a lossy operation with a loss of quality and hence the reduction in filesize. if you want lossless rotation, then you should use the rotate option from the thumbnail view (accessible from right click and from the menus Images->Rotate).  Additionally, there is an option in the imageeditor settings where you can control the level of compression. Set it to high enough (>85) and loss in quality (and filesize) will be lesser, but still never completely lossless.

Additionally have a look at, BUG #87804
Comment 2 Sunny 2005-02-11 20:51:22 UTC 
Hi,
in version 0.7.1 (kde 3.3.2 level "a" unoficial build of SuSE) there is no Rotate item under Image in trumbnail view. There is no right click entry as well.

So, how should be lossless rotation performed?
Comment 3 Sunny 2005-02-12 21:31:23 UTC 
Problem solved. In SuSE kipi plugins are in a separate rpm, so after installing them, everything is OK.

Cheers and thanks for the good work