Helping relief units in Haiti and Chile – from my desk

Helping relief units in Haiti and Chile – from my desk

OSM helped Haiti

When an earthquake struck Haiti in January, many organizations and companies donated geospatial data, and the volunteering individuals involved with OpenStreetMap did a great job putting it together and produced maps of Port au Prince. Not only were those maps accurate and up-to-date, but they also featured information about collapsed buildings, mobile hospitals and emergency accommodations. This was only possible because they could use satellite data that was both up-to-date and extremely detailed – and there was an unbelievable number of such sources.
It’s notable that some days before the disaster, the OSM-maps for that city where a white spot with some lines.

Port au Prince - before and after
Port au Prince - before and after

I heard of it several weeks later, and was very sorry to have missed that opportunity to help and promised to myself to lend a hand the next time something similar happens.

Now Chile needs help – and sources

Last weekend, there was a severe earth quake in Chile, and this time I noticed the incident some hours after it had happened. Of course, there was already something setup in the OSM wiki, but map sources were sparse. Even now, we still wait for up-to-date mid- and high-resolution imagery, and are basically stuck with 10 years old images from Santiago and very bad material for all the other regions.

Images from RapidEye

On Monday, the German company RapidEye AG published a 5000×5000 pixel JPEG of
the city „Concepcion“ and its surrounding area. They announced to publish future
images and a reference from before the earth quake soon. See for more information.
The resolution seems to be 6.5m (high enough to see larger roads, but
too low to actually see any damages). And, sadly, the image suffers
from heavy JPEG compression artifacts. This seems to be tile 1822122
which is (along with other tiles) available from the geodata kiosk at in diverse formats
(GeoTIFF, etc.) but at the same resolution, priced about 186 Euro
(approx. 250 US-Dollar. Maybe there is a way to get it for free, but
following the usual checkout process, that amount would be billed.)
Since I did not plan to pay that amount, I gave a shot at the JPEG. After installing some plugins into JOSM and realigning the picture, my first step was to trace out all the areas which looked like residential buildings. This is a nice trick to indicate where some mapping has to be done: If someone notices those typical gray areas on the map, he can expect residential roads as well. If there are no roads, this is sign for missing data.
Look at this map (it’s interactive) and see for yourself:
[osm_map lat=“-36.806″ long=“-73.072″ zoom=“12″ width=“460″ height=“380″]
After some hours, when I had done all of those gray areas, my eyes (and possibly my brain and the simple neural nets behind my retina) got used to the blurry, low-contrast satellite image, and I was bold enough to actually trace some roads and upload them. But still it’s very dissatisfying to be stuck with that kind of material, unable to do a great deal of helping work.

Areas which in which I did more than just gray surfaces
Areas which in which I did more than just gray surfaces

Fast, faster, OSM

Maybe it’s worth adding that normally it takes about a week until new map features are rendered into the map and can be seen online. I hoped that under the current circumstances it would be a bit faster, and was very surprised and pleased to see that my data was actually rendered and ready for consumption less then 2 minutes after I uploaded it. Wow.

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