GNOME Bugzilla – Bug 423706
Red-eye removal tool (RRT) does not work with people with darker skin
Last modified: 2015-12-18 17:45:26 UTC
Please describe the problem: I was looking at the image on http://planck.djpig.de/~mcornils/rote-augen-kino-mar07.jpg and tried to remove the man's eye reflection with gthumb's tool. Unfortunately, this discoloured large parts of his face. The tool worked well on the woman. Steps to reproduce: 1. load the mentioned image in gthumb 2. click on the man's eyes 3. witness the algorithm spilling into parts of the face Actual results: The algorithm spills into parts of the face Expected results: Only the redness in the man's eyes is removed Does this happen every time? Yes Other information:
The current algorithm works well with "red eyes" that really are red. It does not work well with orange or white eyes, which can also occur in flash photos (as in the sample photo). Suggestions for improved algorithms are welcome... If you are aware of any open-source tools that do handle the sample photo correctly, let me know and perhaps we can use their algorithms. - Mike
Also reported at https://launchpad.net/ubuntu/+source/gthumb/+bug/85780.
Hmm, I didn't read your original report carefully enough. Sorry! As you say, the current algorithm is seeing the skin as "red". Maybe we can use this research: http://ivrgwww.epfl.ch/research/topics/red_eye_removal.html - Mike
Hmm, I used Digikam's (Qt-based application) Red eye tool - while it needs more user interaction (selecting the area of the eye), it works as advertised. If EFPL's algorithm is not helping, maybe an advanced option to draw a bounding rectangle over the eye area (or a circular "patch" with tunable diameter) will work.
Flavien Volken (from EPFL) has sent me his thesis report and some sample code to study. If anyone else is interested in working on this, let me know, and I'll forward the stuff to you. For now, I hope we can improve the algorithm and make the computer do the hard work, rather than requiring extra input from the user. I think we want gThumb to be an "easy to use" tool, rather than another gimp. It will take a while to get it right... - Mike
Interesting library: http://opencvlibrary.sourceforge.net/FaceDetection I think you can feed the software sample of eyes/not-eyes, and it learns to classify them. (The example given is face detection, but I think it is more general than that). - Mike
Marking as obsolete, as the 2.x version are no longer supported. Please feel free to reopen this bug report if it describes a problem that still occurs with a current version of gThumb (currently 3.4.1).