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Suppose you have multiple photos of the same object (from slightly different angles), each have some obstacles in foreground.

First image with an obstacle Second image with an obstacle

You added an alpha channel to each picture and "erased" the obstacle (leaving "holes" in each picture).

First image with a hole Seconf image with a hole

You want to combine them and obtain a picrure without obstacles or holes.

Resulting image

What [open source] software should I use to do this? I tried ALE, but it does not preserve alpha channels. Will Hugin or some Gimp plugin do this?

Update Tried Hugin, got this:

Resulting hugin image

It looks like what I want, hovewer...

  1. It asks for some "lense" while this is not a photo at all. I tried entering "infinity" as focal length (meaning "don't distort anything"), but it just failed in that mode.
  2. It failed to align the size of images until I manually adjusted the "lens" parameter of one of the images. Can it use control points to scale image in addition to moving?
  3. I don't know how to turn off those "photometrics".
share|improve this question
Sounds similar to panorama stitching. – Bob Jan 10 '13 at 12:54
I tried once Hugin for averaging multiple almost-similar frames into one, but it failed with "too many overlapping things"... – Vi. Jan 10 '13 at 12:55
I have just tried Hugin with the above images. In preview it should what I want to do, hovewer when I press "Stitch" button it fails with enblend: excessive overlap detected; remove one of the images – Vi. Jan 10 '13 at 13:06
In Super User, and all the StackExchange sites, shopping or product recommendations are considered off topic and open ended, and sometimes even too localized. Try to reword your question in a way that you are not asking for products, but more of processes; this will help keep it on topic – Canadian Luke Jan 10 '13 at 18:23
I don't clearly understand what is wrong and how the question should be fixed. The question is about image processing (what I need, what I expect, what I tried, what failed), not about shopping (what is exactly a "shopping question" BTW?). – Vi. Jan 10 '13 at 18:48

If your example is accurate, simply add the various images as layers in GIMP. The hole in the top layer will show the good image below. The hole in the lower layer doesn't matter if the top layer has good data for that portion.

Order the layers so that the best image is on top and the worst on bottom.

If you have poor quality areas that you want to average out, that's another matter.

share|improve this answer
Unfortunately, the 'slightly different angles' would break that idea. – Bob Jan 10 '13 at 14:07
Good point. I forgot about that bit. That does make it tricky. – Dane Jan 10 '13 at 14:41
Now I'm really curious if there's a good way. When I have time, I'm going to try out and and – Dane Jan 10 '13 at 14:49
Hugin does the trick (expect of scaling the images to match); but it also does too much. – Vi. Jan 10 '13 at 17:04
I haven't used any of these GIMP plug-ins, but do any of them leave the complete images each on their own layer? If you get to keep all the images, then you could erase foreground problems after the images are positioned and stretched by the plug-in. – Dane Jan 10 '13 at 19:13

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