By sourcing images and applying the principles of photogrammetry and distributed computing, the results are very impressive. They aren’t going to rival laser scanners just yet, but the animations on the Building Rome in a Day project website are impressive, and show the huge potential of this approach.

Entering the search term Rome on Flickr returns more than two million photographs. This collection represents an increasingly complete photographic record of the city, capturing every popular site, facade, interior, fountain, sculpture, painting, cafe, and so forth. It also offers us an unprecedented opportunity to richly capture, explore and study the three dimensional shape of the city.

This particular project aims to create “sparse point clouds” to give a 3D overview of the layout of a city, and has interesting potential for interacting with and exploring a place virtually. They are running a parallel project investigating dense point clouds which looks promising, but probably won’t see any popular use for a long time due to the massive amount of processing and data storage involved (dense 3D point clouds and meshes are huge datasets).

The University of Washington project is similar to Microsoft’s Photosynth project. But the difference is that with Photosynth, users have to manually create “synths” by uploading photos of a particular place. Photosynth does not allow users to tap into the millions of other images out there, which moves me to my next point.

What about the copyright implications of crowd-sourced photos? Even if just using Creative Commons licensed images, imagine what the “attribution” page would look like if hundreds of thousands of images have been used from potentially tens of thousands of photographers. I’ll be interested to see how they deal with that side of things.

But overall, this is an exciting development. There is huge potential for cultural heritage applications, especially in the areas of survey and interpretation. I will be following this project very closely.

This is a great move, since it can be quite daunting if you’re really into knowing (and seeing) where photos were taken, but don’t want to move over to rival Zooomr, or delve into some of the arcane geotagging browser extensions or 3rd party tools. It’s all done within Flickr’s Organizr, and it’s all drag and drop. You can even set levels of accuracy, i.e. associating photos with whole cities, or even down to street level.

Whilst this is great, it’s not actually that great if you live outside of the USA. Yahoo’s mapping for the UK, for example, is very basic. Angular lines mark major roads and railways, and that’s about as good as it gets (unless you want satellite photos of London).

So what do I do to geotag my photos on Flickr? I use the Localize Bookmarklet which was created by the talented aemkei, which uses Google Maps (which has excellent UK coverage). You simply drag the bookmarklet link to your bookmark bar (and rename it to something like “Flickr Geotag”). That’s it. When you’re viewing a photo in your photostream, simply click the bookmark, and the photo will be replaced with a Google map. Navigate to the spot where your photo was taken, and click. That’s it. Hit save, and the geotags will be inserted to your tag list, and a link to Google maps showing the location of the photo will be appended to your description.

At the moment (5th September 2006), this doesn’t add the photo directly into Flickr’s geodatabase, so you have to import them manually (thankfully, it imports all your newly geotagged photos in one go), by following this link (or access it from “Your Account“).

One imported, Flickr will show where the photo was taken as text, e.g. “Taken in London, England (map)” with a link to a Yahoo map which floats above Flickr when clicked. This is on the lower right of the screen, above the date and camera model information.

One observation is that the spatial database behind this all must be pretty powerful. This photograph of a butterfly was taken within the grounds of a medieval park, close to Salisbury in the UK. I geotagged it some time ago using the bookmarklet, and Flickr imported the coordinates when I did my first import a few days ago. I noted that Flickr shows that the photo was “Taken in Clarendon Park, England”. The underlying Yahoo engine (anyone know what it’s called?) has perfomed a spatial query and identified that the photo was taken within the boundary of the park. The fact that it’s a relatively obscure historical deer park reveals that Yahoo’s spatial database must be rather detailed, and the engine that powers it, rather powerful.

It makes me think (and hope) that improved mapping for the UK is just around the corner…

There’s one thing that Flickr doesn’t support natively, and that is the ability to ‘geotag’ photos. In a nutshell, geotagging is just associating spatial data (i.e. a set of coordinates) showing where you took a particular photo (or where the subject is located). You could then see where it was taken on a map, or browse photos via a mapping service such as Google Maps.

A number of determined people have written hacks to get geotagging into Flickr. But these often use a plugin for Firefox called Greasemonkey, and a further set of scripts to build in the functionality into your photo pages. If you’re not technically minded, it’s not easy to do, and I think that most people will be put off by this approach.

If you do use extensions such as GMiF, coordinates are stored in with your tags, so your tag lists will eventually become cluttered with tags such as “geotagged” and “geo:lat=51.519606″ etc. It’s not very elegant, but it does work.

Step in Zooomr.

Zooomr have built geotagging right into the heart of the system, with elegance. Your geotags are nicely hidden away (but still accessible). Viewing where photos were taken, or simply browsing photos by location on a map are all built-in, and very easy to use. Not to mention kind to the eyes.

Zooomr doesn’t yet have the community aspect that Flickr does. Community is what makes Flickr so brilliant, and it is now very well established. I think that startups like Zooomr fill a nice gap at the moment, and help to keep giants like Flickr innovating and on their toes.

Good luck Zooomr!