geography, multimedia

Mapping Photos using GeoRSS

As I was finishing up my earlier post on the geotagging tutorial, Pankaj Garg of ZeeMaps sent me an e-mail. We had previously been in touch about the possibility of using a GeoRSS feed to map photos in ZeeMaps.

GeoRSS is exactly what it sounds like, an RSS feed for geo-encoded information. More people have GeoRSS feeds than they realize— Flickr assigns each user a GeoRSS—although most of those feeds are probably empty since geotagging images is still not a habit for most people.

georss link on flickr page

Flickr enables GeoRSS only for each user’s primary photostream and for individual tags (as in the image above). I mapped the same photos as in the earlier post. The difference this time in the process is that I exported directly from HoudahGeo to Flickr (after enabling geocoded metadata in Flickr) and assigning a unique tag to all of the photos; in this case, I tagged them with the date. (I suspect sets are not available for GeoRSS because you can rearrange image order, unlike in the photostream or tag streams.) This skips the .csv steps in the original tutorial I wrote. But Flickr may limit the number of entries in the feed, limiting the number of datapoints that will go on the map.

As mentioned previously, the advantage of mapping these in something like ZeeMaps is the ease in customizing and embedding the map. While Flickr can map my geotagged photos, all I seem to be able to do with it is link to the map. Here’s the rough workflow I used:

1. Copy the GeoRSS link from the 2008december4 tag page.

2. Create a new map in ZeeMaps and choose “KML, GeoRSS Add” from the Advanced menu:
menu item to add georss link

3. Paste in the GeoRSS link:
pasted georss link

The resulting map:


Photo Geotagging Tutorial for KDMC

The Knight Digital Media Center at UC Berkeley has published my tutorial on Geotagging and Mapping Photos. In it, I go through a set of steps on how to assign location data to images shot on a digital camera and how to use the results to put the images in an online map.

The KDMC guys wanted me to use a specific set of tools: an Amod AGL3080 GPS Data Logger, HoudahGeo phototagging software, Excel, and ZeeMaps.

All of the tools worked great for me—although there was a general failure of the Amod GPS trackers when we tried to download the geodata during our December workshop, so proceed carefully if you choose to use one of those. (I would love any recommendations on other GPS devices for this purpose). The basic workflow is as follows:

shoot photos while GPS tracker is activated —> edit photos —> load photos and GPS data into HoudahGeo —> create .csv file from matched data —> load .csv into ZeeMaps

There are some key details to remember. Make sure the clock on your digital camera is set properly; this is how the GPS data, which records time along with location, is matched with the images. When editing photos, don’t lose your EXIF (time) meta data. And be sure to read the procedures for creating the .csv file in Excel, separating data into columns, etc.—there are a few spots where little mistakes can mess up the file. The procedure, overall, is quite simple.

The biggest surprise, and a pleasant one at that, was ZeeMaps. The service is built on Google Maps, so the output both looks familiar and can be embedded into a variety of contexts. But the real strength of ZeeMaps is the variety of options it gives you: besides the ability to upload .csv files, which can include thousands of data points, there is room for a lot of configuration when it comes to adding different kinds of information and configuring the map for embedding.

That said, the results aren’t perfect. For example, more control over how photos are displayed would be nice to have. And there’s no way to trace out the path that the GPS logger recorded as I walked down side streets and over hills. Other programs do this, but neither my colleagues nor I have found a good service or program that combines all the features we’re looking for. ZeeMaps has the potential to become that, depending on what kind of features it develops. The tech people are incredibly responsive—when I sent a tech inquiry they responded in about a day and plan to incorporate a new feature as a result. I know that the new iPhoto will have photo-mapping capabilities, but have not yet had a chance to try it. I suspect the search for the perfect photo+geodata+display app will go on.

Here is a simple test map I created last month. I’ve also created a map of places I lived on the geobiography page.