Bug 128283 - thumbnail generation fails with raw images
Summary: thumbnail generation fails with raw images
Alias: None
Product: digikam
Classification: Applications
Component: Plugin-DImg-RAW (show other bugs)
Version: unspecified
Platform: openSUSE Linux
: NOR normal (vote)
Target Milestone: ---
Assignee: Digikam Developers
Depends on:
Reported: 2006-05-29 23:51 UTC by Florian Auer
Modified: 2017-07-12 04:42 UTC (History)
0 users

See Also:
Latest Commit:
Version Fixed In: 0.9.0

patch to use dcraw 8.21 to extract RAW thumb instead to use dcraw::parse method (2.55 KB, patch)
2006-06-04 17:45 UTC, caulier.gilles

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Description Florian Auer 2006-05-29 23:51:58 UTC
Version:            (using KDE KDE 3.5.1)
Installed from:    SuSE RPMs
Compiler:          gcc (GCC) 4.1.0 
OS:                Linux

Raw images from my Kodak DSC Pro camera produce only distorted thumnails. After I removed the first part of the loadDCRAW function in digikamthumbnails.cpp ( where it says "first try with Dave Coffin's "parse" utility" ) thumbnail worked correctly, but performance isn't very good, it takes about 5 seconds per picture, which wouldn't be much of an problem, if digikam wouldn't generate thumbnails only for visible pictures... this way it need a lot of time and constant interaction, until a folder with 600 raw images has all its thumbnails. Theoretically thumbnails from the Kodak files could be created very quickly, since they are basicly tiff images an have embedded thumbnails.
Also exif information isn't displayed, but I guess this is more an libexiv2 issue, although I think exif information for the kodak raw images worked in earlier versions of digikam, but I am not sure.

I uploaded a test image to this location:
Comment 1 Florian Auer 2006-05-29 23:53:50 UTC
I forgot to mention I was using the latest unstable trunk, but it also didn't work with rpms from opensuse
Comment 2 caulier.gilles 2006-05-30 08:18:09 UTC
Thanks for this report Florian. I have never tested a DCR raw file before.

Your sample file is vertically oriented. Can you give me another one horizontally oriented.

Also, preview is generated by an old dcraw::parse implementation. Perhaps a new backport of dcraw::parse.c implementation will solve the problem (with dcraw v8.08, dcraw -e foo.dcr give a good preview)...

Gilles Caulier

Comment 3 caulier.gilles 2006-05-30 08:24:17 UTC
Forget to said that using Exiv2 from svn (not 0.9.1) with digiKam give Exif and GPS informations now !

This is not optimum. There is no makernote for example. We will take a look to improve that.

Gilles Caulier
Comment 4 Florian Auer 2006-05-30 11:52:04 UTC
I've uploaded a landscape one

using svn version of libexiv2 improved things, although important information like aparature, shuttertime and others don't display.

perhaps it would be a nice thing, if someone sets up an website where people could submit raw pictures from different camera models, I guess that would help open source developers testing photo software. hmm... I guess I could make something like this, if you are interested, please let me know.
Comment 5 caulier.gilles 2006-05-30 16:29:20 UTC
I have already created a RAW repository at this place :


...but of course, creating a real repository with a web interface and a place to Submit new files will be really powerfull, like this no-opensource repository (very uncomplete) :


Note : RAW file are large data. Hosting a RAW repository require a computer with a big hardrive. Are you sure that you can provide this ressource ?

Gilles Caulier
Comment 6 caulier.gilles 2006-06-04 17:44:09 UTC

Here a patch to solve the problem in digikam thumb generator kioslave. The interanla digikam code using bugous dcraw::parse method have been disable,and extrenal dcraw instance is used instead...

Work fine here, and is speed... but you need to install at least the last dcraw verion : 8.21 !!! ... else thumbs extraction will failed and thumbnail generation will take a while...

Please test it and give me a feedback

Comment 7 caulier.gilles 2006-06-04 17:45:25 UTC
Created attachment 16472 [details]
patch to use dcraw 8.21 to extract RAW thumb instead to use dcraw::parse method
Comment 8 Florian Auer 2006-06-04 23:13:40 UTC
works great thx!

thumbnail generation works quick now (althoght my old apple, using the original kodak utility is still about 5 times faster, but I guess if there was a dcraw lib instead of the command line utility, one could avoid the overhead you have with calling dcraw through popen and the extra conversion to an from the ppm format...)

thank you, Florian

PS: I will have a look about the raw repository next week, I'll let you know when I have worked something out
Comment 9 caulier.gilles 2006-06-04 23:47:43 UTC
OK. thanks for the report. Code not yet commited. I need more feedback from others users.

About RAW repository, i'm waiting your contribution. Thanks in advance for your help