Friday, October 07, 2005
Sunday, October 02, 2005
Geocoding Images For Use in Gallery
I found a handy windows program for geocoding images using gps routes and correlating the gps and photo times. It's called RoboGeo. I used it, along with a modified gpx file to geocode a couple of test images. The program has a couple of options for output, which include generating webpages that work with Google Maps (there is also an XSLT template for generating KML files). These could then be imported into Google Earth. Another option is to simply process all the images, updating their EXIF data to include fields for latitude, longitude, altitude, datum, etc. This is much more appealing since I already have code to import images from Gallery into KML. After processing the images, I used the perl module Image-EXIFTool to verify the EXIF data was updated as expected:
GPS Version ID : 2.0.0.0
GPS Latitude Ref : North
GPS Latitude : 37 deg 42.68' 0"
GPS Longitude Ref : West
GPS Longitude : 112 deg 51.15' 0"
GPS Altitude Ref : Above Sea Level
GPS Altitude : 2999 metres
GPS Time Stamp : 6:7:18
GPS Map Datum : WGS 1984
This is everything I need. I'd prefer the latitude and longitude be in decimal format but its easy enough to regex those parts out and do the conversion. It would seem a solution for Spain is at hand. The one remaining problem is that Gallery 2, while it supports EXIF data in summaries and details, does not allow you to select all of the possible EXIF fields. I'm not sure the "GPS Latitude" is even a standard field name. So now I must figure out all the queries that will take these EXIF fields and insert them into the Gallery 2 database as custom fields. Once thats done I will have a process for generating the geocoded images and automatically updating the KML for viewing in Google Earth. In tour mode, this will allow me to recreate the trip in pictures within Google Earth.
GPS Version ID : 2.0.0.0
GPS Latitude Ref : North
GPS Latitude : 37 deg 42.68' 0"
GPS Longitude Ref : West
GPS Longitude : 112 deg 51.15' 0"
GPS Altitude Ref : Above Sea Level
GPS Altitude : 2999 metres
GPS Time Stamp : 6:7:18
GPS Map Datum : WGS 1984
This is everything I need. I'd prefer the latitude and longitude be in decimal format but its easy enough to regex those parts out and do the conversion. It would seem a solution for Spain is at hand. The one remaining problem is that Gallery 2, while it supports EXIF data in summaries and details, does not allow you to select all of the possible EXIF fields. I'm not sure the "GPS Latitude" is even a standard field name. So now I must figure out all the queries that will take these EXIF fields and insert them into the Gallery 2 database as custom fields. Once thats done I will have a process for generating the geocoded images and automatically updating the KML for viewing in Google Earth. In tour mode, this will allow me to recreate the trip in pictures within Google Earth.

