Geotagging for Flickr using Picasa and Google Earth

Flickr's new geotagging tools are fun. Apparently they've had over 1.5 million photos added to maps since they launched the service at the weekend, which is quite impressive! I geotagged all the shots from my March trip to New York, and it's cool to look at the resulting map then turn off the filter so that everyone's photos are visible. You can see similar shots at all different times of the year, which works particularly well in Central Park.

While trawling around the forums I came across a good method for geotagging photos before uploading. If you use Flickr to store your photos online, Picasa to organise them and would like to geotag them easily, there's coolness afoot:

1. Pick up the new beta version of Picasa from here (you'll need a Google Account, I think) and the Google Earth 4 beta from here.
2. While they're downloading, make sure you're logged into Flickr and go here and confirm you want EXIF data imported automatically.
3. Using the new Picasa, select a bunch of photos that you want to locate, then go to the 'Tools' menu and select 'Geotag' -> 'Geotag with Google Earth'
4. GE will then open, and you can use the full power of its search capabilities to find the correct location. Hover the crosshair over the appropriate area and click 'Geotag', and repeat for each picture in GE's window before hitting 'Done'.
5. The latitude and longitude data have now been added to the actual JPEG file and are combined with the existing EXIF data. Send the pics to Flickr in the normal way (I tend to email them from Picasa, or if there are a load I'll export them and use a bulk uploader). Flickr will automatically recognise the mapping data and add the images to its geotagging database.

I only found out about the Flickr's EXIF Import option from a post in their forum - it doesn't seem to be accessible from the standard Account options screen as yet.

Obviously this doesn't work for photos already uploaded, although it'd theoretically be possible to 'replace' each one with a mapped-up copy. I've been using the localize bookmarklet, which works well but is far slower than the built-in interface would be. However, Flickr today released their mapping APIs and have explicity stated that people can build applications using other providers' maps, so hopefully there'll be a decent equivalent within a week or two.