Since getting a new Android phone, I’ve been playing around with logging GPS data. I’ve been using GPSLogger, which can be configured to create KML files right on the phone’s SD card.
As an experiment, I set up my phone to log my current location hourly and took it with me on vacation to Florida. Normal people probably buy souvenirs on vacation; I came back with GPS logs of the entire trip.*
I wanted to do something interesting with the data I had, and generating some kind of image sounded like a fun idea.
I started by writing some PHP code to accept a range of X / Y points and use the GD library to plot them on a blank image. If the same pair of points appeared more than once, the plotted point would increase in size. This way, the size of a point would indicate how much time was spent there.
Once the basic point plotter was working, I wrote some additional code to parse the KML files and interpret the GPS coordinates as points. I fed in the data from Florida and got this image back:
I put the code up on GitHub. Feel free to experiment with it.
* Except for when GPSLogger just stopped working for no reason.