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Here i am, David, aka ThaNerd. Basically, i'm just a blogger who likes doing useless things, even though they're not that simple to achieve. And i guess helping building OSM is part of those not so simple things i'll like to do. I'm set up with my camera, my laptop with Gentoo and Josm on it, and my Holux GR-213 well set up, mapping around Brussels (belgium) and some other areas i happen to know quite well (all in belgium)

Out of this, i have a blog: (in French)

So, my tools for mapping:

  • a laptop : Acer Extensa 5010, bought for 400€
  • a GPS receiver : Holux GR-213, thru USB
  • a Sony PSP, with the "PSP-290" GPS antenna, homebrew-enabled, and often the most recent version of MapThis!
  • a digital camera : Samsung Digimax S700 (7,1MPix)
  • Gentoo
  • Josm
  • a tiny car: Toyota Aygo

How I map

First, I ride by car, equipped with my laptop PC, having a few programs/scripts running:

  • Josm, with the LiveGPS plugin enabled
  • some script i wrote, which record raw NMEA output from my GPS using gpspipe, then reformat to .gpx and compress
  • xgps, part of GPSd, to check the quality of my positioning and "raw" position
  • navit, a program displaying maps from OSM (which i download minutes before i leave home) so i can see if the area where i am lacks (or not) the streets i see IRL
  • kismet, and i'll tell you why way below.

With my camera, i take pictures of the PSP screen and laptop screen both displaying the GPS time, because that's the time used in the gps traces logs. Actually, i don't use my PSP when i just do car mapping...

At some points, i park my car, and take my PSP with me. I take pictures of some useful elements, such as street signs, speed limit marks, and various other things. The use of the PSP is so that my position is still correct after i'm a few hundred meters away from my car (and laptop + gps).

Before I leave the car, i save my traces to disk with a meaningful name. The PSP saves automatically.

When back home, i place all my pictures computer, and open the traces and photos in geotag, so that it adds exif geotags into pictures.

Then, i open the traces from both sources in josm, and zoom to their area. I download the OSM data for that area... For places that are "correctly" mapped, i only add information that lacks. When i see a difference (of more than a meter) between my data and OSM's data, i try to see who mapped it, and how the person maps (some do map only from satellite images). Depending on what i find out, i edit (or not).

In all cases, i upload my pictures to Picasaweb... I tag my pictures with all (useful) words contained in street names, in all languages written on them. See the pictures there. I mostly photograph street signs and traffic signals, and geocode the pics on Picasaweb.