Sunday, March 18, 2012

Geocoding photos with TopoFusion

UPDATE: Check out ten reasons TopoFusion rocks.

My wife and I devote one day most weekends to a mountain bike ride and, while I was going to wait to do a post on this subject, a bear cub just gave me a great opportunity to showcase an easy method of geocoding photos. We had only gone a few miles today when my wife said, "bear cub!" Sure enough, a couple hundred feet away, a cub was ambling back and forth between the logging road we were on and the roadside vegetation. I quickly got out my camera and snapped a few shots, including the one at right below.

When we returned home, I immediately launched TopoFusion, and downloaded Img_0310_cropped_4the track. This software has a feature called PhotoFusion , that automatically links digital photos to where they were shot. How? Your GPS records a timestamp for every track point, while your digital camera records a timestamp in the EXIF data. About all you have to do with TopoFusion is tell it what directory the photo is in. I have yet to see an easier and more elegant solution, especially in software that has such an extensive demo mode that you might not even pony up the $40 for the program.

Better yet, one click creates an HTML image map, allowing you to post a clickable map to your website, which my webmaster/wife did for today’s trip. Before clicking to see it, here are a few things to be aware of:

  • Click in the upper-right corner to toggle between aerial photo and topo.
  • Move the cursor over the camera icon near the center of the map to see a thumbnail in the upper-right corner.
  • Click the camera icon to open the image.
  • An elevation profile and metrics are at the bottom of the screen.

Okay, check it out! Pretty cool, huh? Note the crappy satellite coverage though. Granted, it was in a redwood canyon, but it was extraordinarily bad today. And Bear Haven, aptly, is the name of the creek we biked up!

Oh yeah, one last thing. There is a full chapter on TopoFusion in my book.

About Rich Owings

Rich is the owner, editor and chief bottle-washer for GPS Tracklog. Connect with him on Twitter, Facebook or Google Plus.

Comments

  1. I’ve come across three or four of these GPS/photo merging programs now. I’m curious how accurate they are, since camera clocks are not nearly as accurate as GPS time. If I was to write one (which I might, for Unix instead of peecees), I’d have it look for parts of the GPS log where you were stationary, and try to match those up with the photo times and figure out the camera’s current offset from GPS time.

  2. Excellent point! The key here is to check the time on your GPS and use that to set the time on your digital camera. Your GPS is definitely the most accurate time piece you have, since it is constantly updated by the atomic clocks on the satellites.
    Now if you are talking about accrued inaccuracies in the camera clock, that is another matter!

  3. Hi Rich, didn’t know you had a blog 🙂
    I just thought I would chime in a little on Photofusion and the comment regarding accuracy above. The only way Photofusion (or any softwares with said feature) can do this is using averages – first determining what 2 points on your gps track a specific photos timestamp falls between, then averaging the photos timestamp between the 2 track points to find where the photo was thought to be taken. I am sure there are some other factors that come into play (how smart your gps is in taking tracks, using travel speeds, etc.), but this is the basic theory. And this works fine on a most levels and is fairly accurate – especially if you are constantly moving and taking quick photos, then you keep moving. No time for dilly-dallying!!
    On my website I am in the business of collecting waypoint data (among other things) and associating photos with them. I learned of this deficiency by stopping for an extended period of time and taking several photos at a single spot. Then we would continue our ride. When I got home and plotted these photos to the track, I noticed they were all not in the ‘spot’ – they actually started to plot down the trail.
    The lesson i learned? For exact coordinates, this is not the tool. It’s close, but not perfect. For more general use and everything else though, Photofusion rocks!

  4. Does anybody have a similar site for marine charts> I can’t use topos I need to be able to use actual marine charts and all I can find is Maptech and it is limited.
    Frank,
    American by birth….Alaskan by choice

  5. Hi Nathan-
    Good to hear from you. Thanks for taking the time to reply. I wonder how the track log is set up in your GPS. Looking at my 60CS, you can set it to track by distance, time or automatic. The manual isn’t clear on how “automatic” is calculated. It seems like you could overcome the issue you mentioned by choosing time, if that is an option in yours. Then there is the other problem of taking photos in one spot – the camera icons are all on top of each other! This was an issue with the bear cub photos, so to overcome this for the website I just left one photo in the file.

  6. Hi Frank-
    I wish I could point you in the direction of a site focusing on marine GPS / charts. I’ve got my hands full just trying to track terrestrial developments though! Seems like I’ve seen a sailing group focusing on GPS, but a few searches turned up nothing.

  7. I have read that Fugawi deals rather well with the new NOAA Electronic Navigational Charts (ENC or S-57 format). Sure wish that some other programs did!

  8. CAN ANYONE TELL ME WHERE I CAN GET THE POI AND SPEED CAMERA SOFTWARE FOR THE UK SPEC PACKARD BELL 400 PLEASE?

  9. Have you asked at one of these forums?
    http://www.gpspassion.com/forumsen/default.asp?group=2
    They have a forum on that model and a couple of POI forums.

  10. Bob owen says:

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