Saturday, June 19, 2010

Open Remote Sensing

Right after the recent Haiti earthquake a community of volunteers put their efforts together in order to build up to date maps of the area in order to help the humanitarian aid on the terrain.

This community is the one who is contributing to Open Street Map (OSM), the wiki-like world wide map on the Internet. A detailed presentation about this activity can be watched here.

This kind of activity can only be carried out if the volunteers have the input data (images, gps tracks) and the appropriate tools (software).

In terms of software, the OSM people rely on open source state of the art tools which allow them to be quick and efficient. As far as I know, their infrastructure is based on OSGEO tools for the storage, the formats, the web services for edition and visualization, and so on.

So open people with open tools generating open maps is something which has been proven useful and efficient for a while now: just take a look at the status of OSM near where you live in order to convince yourself. This is another example of the Wisdom of Crowds phenomenon.

However, one thing which was really special in the Haiti case is the speed at which the maps where created after the earthquake. This may be surprising when one thinks that most of the work for OSM is based on gps tracks submitted by people which are on the terrain or by volunteers digitizing somewhat outdated aerial imagery.

In the Haiti case, what really allowed for a quick cartographic response was that space agencies and satellite image providers made freely available the images acquired not long before and after the event. This allowed for really accurate maps of the communication infrastructures and buildings as well as a damage assessment of those. Refugee camps could also be easily located.

Unfortunately, the availability of this kind of data is not usual. Even with initiatives as the Disasters Charter the images made available by the signing parties and the added value maps are distributed under licenses which are relatively restrictive.

And as one can easily understand, the open people using open tools to create open maps are completely useless if they don't have the images to work with. Many people will agree on the fact that this should change when lives are at stake. Other people will think that, even for general purpose cartography, data should be freely available. Of course, space agencies, the aerospace industries, etc. have hard (economical and industrial) constraints which don't allow them to give away expensive images.

And of course, a bunch of volunteers don't have the resources to put satellites in orbit and acquire images. One thing is writing free software and another thing is rocket science! Or is it?

It seems that a group of people are thinking about doing things not far from that.

The Open Aerial Map project aims at building a world wide cover with free aerial images. Even if the project has been dead for a while, it seems to be active again.

Another interesting initiative is the Paparazzi project which aims at building open source software and hardware for aerial unmaned vehicles. One of the projects using it is made by the University of Stuttgart and aims at developing a system for high resolution aerial imagery.

The list of interesting free projects which could be used to setup an open source global nearly real time mapping system is long. It is likely that all the bricks will be put together someday by volunteers.

If this comes to reality, I suggest just one restriction on the license: the user wanting to print the map will have to read Borges' "Universal History of Infamy" before choosing the scale.