Occassional thoughts about orienteering
Monday, June 11, 2012
A modest lidar-based orienteering training map
If you're interested in how lidar (aka laser scan) data can be used to generate orienteering maps, you need to be checking out what's going on over at RouteGadget.
I don't have the computer skills to do as much, but I'm learning. I spent some time this weekend looking at some very interesting terrain and creating a map with OL Laser. I thought I'd share what I've been doing.
From the lidar data - which I was able to find and download for free - I generated 2.5 meter contours. I also generated an "intensity" image based on the ground. From the intensity image I was able to pick out roads, trails and parking areas. I could also make out vegetation from the intensity image (which is something like a black and white photo). But, I decided to use the vegetation data in the lidar to generate vegetation information.
To create a rough vegetation map, I used OL Laser's object height feature. For anything below 0.8 meters, I created a light yellow shade. For everything above 0.8 meters, I created white areas (to correspond to forested areas).
You can see the results below.
I'm guessing the forest might be a little bit thick, so I also created a version where I shaded objects above 0.8 meters with light green.
You can see an air photo of the area below and see how it matches up. To provide some context, the area shown is about 1.5 km from east to west.
I haven't been to this terrain. It certainly looks very interesting. I think it must be some sort of sand terrain. I expect that I'll know more once I've had a chance to see it in person.
One thing I haven't done (and that's just because I've been lazy), is use the latest version of OL Laser. I need to get my act together and download the latest version.
Back to okansas.blogspot.com. posted by Michael | 8:21 PM
I would like to try using OL Laser, but I am not sure what to download or how to get started. Do you have any tips?Post a Comment