Bug 206712

Summary:	Raw Import Tool: RGB (linear) provides gamma corrected output and should be named as such
Product:	[Applications] digikam	Reporter:	Milan Knížek <knizek>
Component:	Plugin-RawImport-Native	Assignee:	Digikam Developers <digikam-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	caulier.gilles
Priority:	NOR
Version:	1.0.0
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed In:	1.0.0
Sentry Crash Report:

Description Milan Knížek 2009-09-08 07:22:32 UTC

Version:            (using KDE 4.2.4)
OS:                Linux
Installed from:    Compiled From Sources

digiKam current svn, libkdcraw7 4.2.2, kipi-plugins 0.6.0.

The Raw Import plugin for digiKam's editor offers to output the image in linear RGB. However, it applies gamma correction to the image (in both 8 and 16 bit colour depth) and therefore the output is not linear RGB data.

Hence the option in Colour Management tab should be renamed to "RGB (gamma corrected)" to avoid confusion.

Comment 1 Milan Knížek 2009-09-08 07:37:38 UTC

I made a small mistake: the option of Workspace in CM tab is currently named "Raw (linear)", so possible change of the name would be "Raw (gamma corrected)".

Comment 2 caulier.gilles 2009-09-08 08:05:38 UTC

Another mistake : Raw Import tool is not a kipi-plugins but a tool coded as well in digiKam core. It's not a plugin.

To avoid gamma corrected in linear mode, use libkdcraw from trunk or from KDE 4.3.x. There is a new option to disable gamma correction.

See these screenshots for details :

http://farm4.static.flickr.com/3500/3899707834_acc9674420_o.png
http://farm3.static.flickr.com/2459/3898926077_9431fdbc5f_o.png

For me this entry is invalid...

Gilles Caulier

Comment 3 Milan Knížek 2009-09-08 21:12:55 UTC

Okay, it is good that it is possible to switch off the gamma correction.

I have compiled digiKam against KDE 4.3.x in Ubuntu 9.10 and the image preview looks like linear.

However, I would disagree that the entry is invalid -> if the user keeps the default settings (auto brightness on), then the output workspace is not "Raw (linear)" but gamma corrected.

Taking into consideration that it can be both gamma corrected and linear, and that the user can select arbitrarily any camera profile (I am not sure what is the colour transform then), a different name would avoid confusion.

E.g. "RGB (no profile assigned)". This should cover all the above mentioned situations.

Comment 4 caulier.gilles 2009-09-09 08:29:49 UTC

SVN commit 1021414 by cgilles:

raw (linear) => raw (no profile)
CCBUGS: 206712


 M  +1 -1      dcrawsettingswidget.cpp  


WebSVN link: http://websvn.kde.org/?view=rev&revision=1021414

Comment 5 caulier.gilles 2009-09-09 08:31:13 UTC

SVN commit 1021415 by cgilles:

backport commit #1021414
CCBUGS: 206712


 M  +1 -1      dcrawsettingswidget.cpp  


WebSVN link: http://websvn.kde.org/?view=rev&revision=1021415

Comment 6 caulier.gilles 2009-09-09 08:32:32 UTC

SVN commit 1021416 by cgilles:

raw (linear) => raw (no profile)
CCBUGS: 206712


 M  +3 -3      dcrawsettingswidget.cpp  


WebSVN link: http://websvn.kde.org/?view=rev&revision=1021416

Comment 7 Milan Knížek 2009-09-10 20:44:25 UTC

Thanks, Gilles, this is fine, too.