[HOT] Haiti 2010

Mikel Maron mikel_maron at yahoo.com
Sat Sep 11 21:32:37 BST 2010


Agree with the general gist of what Fred outlines.

Note that nothing in the OSM API would prevent automated or semi-automated 
methods from contributing to OpenStreetMap. It's open for experimentation, and 
if we found it effective, then great. But for the time being though, I see the 
"traditional" OSM approach as working best :)

 == Mikel Maron ==
+254(0)724899738 @mikel s:mikelmaron
http://mapkibera.org/
http://wiki.openstreetmap.org/index.php/Haiti




________________________________
From: Fred <fmoine at hotmail.fr>
To: hot at openstreetmap.org
Sent: Sat, September 11, 2010 4:05:15 PM
Subject: [HOT] Haiti 2010

 
In reply to sam         larsen mail and from my experiences at Unosat (rapid 
mapping)         and Keyobs         (project development, mining extract 
building with satellite         imagery, Kibera,         Somalia). 


As part of the emergency: 

We must         reduce the processing time or find other partners who have         
capabilities to         provide images correctly georeferenced. 

For now, there         are very few suppliers provide use (except in exeptionnal 
case         such as in         Haiti). 

So in general we do what we can to georeference images         rapidly to         
realize extractions (of floods, destruction, road...) 

So it means that we have access to the imagery and got some         specialist 
to work         with.
 So         the ideal is to have strong relationship         with the supplier 
or other team.
 

After manual extraction or semi automatic topics: 

To extract manually  information of         roads,         settlements, damage 
building, IDP is still a valid method . 

For several reasons: 
1 - Semi-automatic extraction ask a strong expertise and         need to be 
cleaned. 

In the final         geometries of heterogeneous objects which remains difficult 
to         read the         information or calculated surface or accuracy 
problems centroid         (as in houses,         we need to catch the centroid). 

2 - Then there is a question of time, we should be releasing         information         
quickly. So the more you have information on the area and better         
priorities         will be set up. 



In practice,  remote sensing software         need to be improve to extract 
information correctly from imagery         for         humanitarian field of 
operation . As all the software and Remote         Sensing         algorithm 
have been designed for developing countries. 

Only         recently algorithm has been refined and  look         accelerating 
to deal with automatic         extraction. 


However it is clear that we should use the fastest techniques         and 
adapted them to         the field. 

For humanitarian, manual digitizing is still important to         respond 
quickly to a         need. 


And so we use the automatic extraction to retrieve information         from the 
image         and then you end by hand. 


Example  Haiti 2010: 200 000         digitalization         point damage 
building. Unosat was in partnership with SWISS TOPO         (National Geo…).         
And we did not use  Remote Sensing for         the extraction (very bad result 
and no time to improve it). 

And impossible to recover the roads in this complex area urban. 

Gaza: Land cover and damage building, semi extraction( software         
E-cognition).         It is true that we could recover the roads, but it was 
quicker         to do it by         hand. 


Sri Lanka: IDP movement, 65% semi-automatic method (pretty         clean) and 
the rest         by hand. 


Kibera: Semi Automatic method and we finished by hand.
Besides, as many cities in Africa are the pixel values are         mixed. There 
is a         lot too clean. 


OSM would have to launch a cleaning roads with their volunteers         if they 
are to         distinguish houses to the road J

At  the         end, it's very frustrating to have student         years to 
finally extract the information by hand. 


But when it's information are crucial to crisis         management we should not         
hesitate a moment. 


For the case of OSM, as you are dependent of imagery (so         the body of         
crisis management). We must join with other partners who have         the means. 

And give the         soul and symbol of social mapping. 
 For       the crisis mapping seminar :
After having participated in Haiti alongside with HOT, these       activities 
has       given a windows to the people to be involve in this crisis and is       
it the most       important.
If you look at the humanitarian action today, the population is no       longer 
involved.       Neither in short-term and a little in a long term (proposal 
phase,       meeting       phase, etc…).
The question is how we let people speak and not only the       consultant, the 
UN       agency for their country.

A + fred all the best from Pakistan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/hot/attachments/20100911/902b8880/attachment.html>


More information about the HOT mailing list