Ciaran McNulty

Arthur C Clarke once said that any sufficiently advanced technology is indistinguishable from magic. I always knew that some day something would come along that my brain just couldn't comprehend, I didn't realise that would happen before I was thirty.

Stitching panoramas together is something we've all tried to do. I've in the past spent some unproductive hours in Photoshop trying to scale, skew and match snaps together myself. I've also spent hours adding 'control points' to images in various shareware applications, all with middling results.

However, I appear to have been missing out on a big revolution. Nearly five years ago M. Brown and D. G. Lowe presented a very interesting paper that you can read here (PDF). They came up with an algorithm called 'Autostitch' that had some interesting properties - given a large set of photos it can identify which of them have common features and stitch them together on its own - without any user input at all!

Frankly I was suspicious that it would work, but I gamely downloaded the demo of Calico, a Mac app that implements Autostitch.

I was amazed by the results enough that I got the full version almost immediately. The first sequence of photos I gave it was the following:

With basically no intervention from me aside from selecting the photos in a file dialog, Calico generated the following:

Pretty impressive stuff! A bit of cropping in photoshop and it tidied up pretty well:

I can sense that I'm going to spend a lot of time on holiday in future standing in one spot slowly rotating with my camera!

A couple more shots I've done, to show how good the results are. I really can't stress enough how simple the software is - it's a couple of clicks and bingo, a nice high-quality panorama pops out.