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Panoramic Stitching Software

Hugin LogoA few folks have asked me about the software I used to create the panographic images linked in earlier posts on this site. This question has a short answer and a longer explanation. The short answer is that I used a free (as in beer and speech – it costs nothing and the source code is freely available) tool called Hugin, which is actually an interface upon a collection of underlying panographic imaging tools that has been around for some time. In other words, Hugin simply provides an easy interface for you to use some other tools, which, while powerful, were never designed to be easy to use by themselves. Hugin runs on Windows, Mac OS X, and Linux, and I can strongly recommend it. I can also strongly recommend carefully reading through the FAQs and other documentation available with it, because it will save you a lot of aggrevation when you are making your final panographic images.

Making panographic photos is pretty straightforward, once you figure it out or someone is able to show you. There aren’t a lot of good tutorials on the Internet for this, and I think is probably due to the fact that the user-friendly tools, like Hugin, are so new. We will probably see more tutorials and examples appear over time.

All panographic images start with picture taking, and most digital cameras sold today will work fine to create panographic images with tools like Hugin. My old but trusty Canon PowerShot S40, like most Canon digital cameras (my favorite brand for digital imaging), includes a feature called Stitch Assist that helps you line up each image so that you can just take one shot after another, rotating in a circle, until you have a 360-degree view. Canon Stitch ModeThe LCD screen in on the Canon displays half of the previous image so that you can use it to make sure that the new image you are taking lines up and overlaps the previous image. Each of the files created using this feature are named differently compared to standard images, so that they can be easily linked to one another when you are ready to stitch them together. It is highly recommended to use a tripod when making these images, because you can make sure that the horizon lines up for each photo and you don’t have use the stitching software to compensate for the camera turned a few degrees either way.

It is worth noting at this point that you do not have to make a 360-degree panographic image. I’ve made a few of those, but you can can make an impressive 180-degree or less panographic image out of only a few photos. This is what I did with the Wanaka panographic image.

After you have pulled the images that will make up your panographic picture off of your digital camera to your hard drive, fire up Hugin and drag the images into it’s window that will make up one panographic image. After you are sure that all of the photos are loaded in the right order, you need to start making control points, or links that stitch one photo with the next photo. You might select a particular peak on a distant hill or a big rock in the foreground. As long as you set the control points that refer to the same item that appears on two images and are pretty exact about it, everything will work fine. You will need to set about 10 control points for each image. Importantly, you should also set a horizontal control point that marks the horizon for each image. This tells the stitching software to keep those two images on the same horizontal line and is critical when it comes time to optimize the image. This is what the stitching process looks like on Mac OS X:

Control Points on Mac OS X

Once you are done stitching, you should optimize the image by clicking the Optimize button in the Optimize tab, and then you should bring up the Preview window to set your borders for the image, and well as designating a center for the image. At this point, you are ready to stitch together an image and see how it turns out. If it looks bad, you can go back to Hugin, change some settings or control points, re-optimize, and create another image. The whole process to create a panographic image from stratch is about an hour, and re-creating final panographic images from your Hugin settings only takes a few minutes. This process is computationally intensive, so make sure your computer is up to the task.

I got started with panographic photography with QuickTime Virtual Reality (QTVR), which was something Apple introduced in the 1990s. While living in Australia during 2001-2002, I worked as consultant on a project to create a panographic service website for real estate pros. While that project didn’t end up going anywhere, I learned a lot about panographic imaging, including using what had become the standard free toolset, Panorama Tools, originally created by Professor Helmut Dersch of the University of Applied Sciences Furtwangen (yes, that’s an actual city name). I used the PTViewer, originally written by Dersch, to display panographic images on a web page.

In a lot of ways, panographic software is a great example of the promise, challenge, and opportunities associated with open source software. Dersch developed some fantastic, free software that made making and displaying panographic images much easier. Thankfully, he released the software under an open source license (well, most of it), which gave other geeks like me the ability to see the source code, necessary to build new copies of the software, fix bugs, and make improvements. However, Dersch was forced to shutdown his website and development due to the threat of a lawsuit from iPIX, a company already doing panographic images. (More info on this is available here.) However, while Dersch was stopped from doing development, the source code lived on, and while the threat of a lawsuit hung over developers, after a while, a number of polished tools started to appear. Today, you have the choice of using a free tool like Hugin to use the Panorama Tools, or you can choose a commercial software package that gives you some technical support, such as PTgui. Both of them build on the excellent work of Professor Dersch, and they wouldn’t be possible without the original open source development of the core utilities.

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