[ptx] Enblend suggestion: focus score weighting

[Rik Littlefield]

Sebastian,

What you propose makes a lot of sense.  I think there are no fundamental 
problems.  See my post at 
http://www.email-lists.org/pipermail/ptx/2004-May/001596.html .  There 
is also recent discussion of other approaches & software for this 
problem on Max Lyons' forum at 
http://www.tawbaware.com/cgi-bin/forum/cutecast.pl?forum=3&thread=759 .  
I have played with the various softwares mentioned there (Helicon Focus, 
CombineZ, and AutoMontage).  For my purposes they all have drawbacks -- 
either lack of quality or lack of control or high cost or limitations on 
image size -- so I would very much like to see some sort of 
mask-by-focus capability incorporated into the ptx  family of software.

--Rik

Sebastian Nowozin wrote:

>Hello Andrew and ptx people,
>
>
>lately I have been stitching a very large panorama with a complicated setup (a
>glass-shelled visitor platform on a skyscraper with a ~30m radius circle to
>walk to get all the pictures). Anyway, the net result was that I had 109
>pictures, some of which were clearly out of focus and most were redundant and
>overlapping. I was faced the problem of how to easily find the out of focus
>pictures while still retaining the whole panorama.
>
>  At first I thought maybe enblend could help and calculate some "focus score"
>value for each image or even just parts of it, and use it to prioritize the
>order of images, leading to an optimal end result, using the minimum
>out-of-focus part of the images possible. And also, as far as I understand for
>enblend an image is either completely redundant (removed), or used completely.
>
>  The more I thought about this problem, the more attractive a generic solution
>appears to me: For all redundant overlapping images, prioritize the images
>based on a in-focus weighting function and use only those part of the image
>that scores highest among all images covering that part (except the image it
>will be blended with of course, or use a "minimum border size" threshhold).
>
>  While my problem is easily fixed by more careful photographing and manual
>sorting of the images, there is a interesting possibility if such feature would
>be possible: You could take an image that is in-focus everywhere. Imagine
>taking 8 images from the same POV but changing the focus everytime. Now it
>would be easy to stitch and merge them all into one all-in-focus image.
>
>A quick search brought up the following paper:
>http://citeseer.ist.psu.edu/549905.html
>The part about "focus score" is interesting.
>
>  Is such feature possible or can this already be done with existing tools?
>
>
>Thanks for consideration,
>Sebastian
>
>  
>