Wednesday, September 6, 2006

Image Stitching

One of my game shelves

For many years, I've found the idea of image stitching, where a piece
of software takes several overlapping images and constructs one larger
image from them. Years ago, I looked for a program to do this, and
was always disappointed in the results. I even wrote one of my own,
in Java, using a simulated annealing algorithm that worked quite well,
but still not as well as I'd like. Since then, every couple of years
I've checked out the current offerings and always walked away a little

What I've been hoping for is a program that is

  • wholly automated and doesn't require pre-aligning or tweaking the images,
  • usable with handheld shots, not just nicely rotated images taken off a tripod,
  • able to use not just horizontal arrays, but full grids of images, and
  • capable of producing reasonable results with indoor and near objects, rather than just landscapes.

My own algorithm worked fine with tripod-shot landscapes of arbitrary
composition, but I don't shoot with a tripod much, so it's not really
useful to me. Well, I recently did some more research and I finally
found something that meets my needs, and another one that came close.

The winner is Calico by Kekus Digital. Calico is the fully automated version of PTMac, a supposedly very nice stitcher which involves a lot of tweaking. Calico
essentially doesn't allow any tweaking. You open up all the images,
tell it to stitch, and it does. It does remarkably well with handheld
shots and even does funky angles very well. For the "easy" case of
mostly horizontal panoramas such as this "small" one of the 2005 Blizzard, it does a
flawless job. For the harder case, such as the game shelf shown,
where the images were taken very nearby and there was a large array of
images (over a dozen), it does outstandingly. There are some issues, but they are remarkably minor. If you want a closeup to see the imperfections, check out this 32+ megapixel composite of one of my my game shelves. If you want to see an essentially flawless one, check out this 8 megapixel 180-degree composite of Baltimore, constructed from original 2 megapixel images. Calico is $39.

The runner-up is DoubleTake which has a far better user interface and is a real pleasure to use,
but doesn't do nearly as well on the multi-row short-range handheld
stitching as Calico did. DoubleTake is also less than half the price
of Calico, at $16.

1 comment:

  1. Thanks for sharing this post. Relevant information.

    panorama creation