Where Was I When I Snapped That Photo?

You always think that you'll never forget the name of that special Parisian restaurant, or the plaza you strolled through for lunch, or that mountain hike. But we all forget.

The savviest of us have been using geocoding to embed geographic information from a GPS within a digital photo. The basic idea is that when the camera knows the mapping coordinates of your location it can store location-specific information as part of the file's metadata. (A variant of geocoding is geotagging, in which external tags outside of the photo provide location information.)

In order for geocoding to work you need some way to get GPS coordinates to be a part of the photo's metadata. A few cameras like Sony's have built-in GPS and do this automatically (think expensive). Another solution is a bundled camera and GPS with special software available from Pentax and Garmin. Flickr offers a built-in, simple, manual geocoder that lets you drag and drop photos onto a map. Do-it-yourselfers can use their own GPS and digital camera by following Make Magazine's instructions, but it requires time and will.

Here's how geocoding with a GPS works. The GPS records a tracklog and matches up your coordinates with a particular photo based on the date and time of both the photo and the GPS. So if you shot a photo yesterday at 11:45 AM, the software will read through your GPS tracklog, determine your coordinates at that time, and compare it against the time stamp on the photos to determine your location.

As I was roaming the aisles of DigitalLife, a pre-holiday consumer technology fest, I got a demo of an inexpensive $135 geotagging product called PhotoFinder GPS from Merax. It's a very basic GPS with photo-mapping software. You can use any digital camera with it.

The GPS is too simple for most applications because it has no display screen. But it does store coordinate information and time stamps. Keep the GPS turned on as you take your photos and then run the special software once you're back at your PC. The software synchronizes the GPS coordinates and the photo. Better yet, the software is integrated with Google Maps/Google Earth and Flickr, which means that you can zoom into the street-level maps and see a detailed close-up of where the photo was snapped. The rechargeable battery lasts 21 days according to the manufacturer. The unit uses a USB connection to plug into your computer.

In a demonstration the company pointed out just how many ways the PhotoFinder is useful. Real estate agents or prospective home buyers can take pictures of a home and then locate it on a map. Hikers can keep track of where they've been on the trail. And the litigious, well, they can use the GPS to prove that they really were making a left turn when they were side-ended.

I only watched the demo and haven't yet tried it out for myself, but I'm all over it.

Anyone else had good experiences with geocoding or geotagging? For a really comprehensive piece on geocoding read Richard Akerman's thorough description.