[HOT] [Talk-ca] Flooding in Richelieu River, Quebec, Canada :Follow-up(Complement of information)

Jean-Guilhem Cailton jgc at arkemie.com
Sat May 28 12:07:18 BST 2011


Hi,

Great find Daniel !

To use directly the GeoTiff images in JOSM, you could try the
ImportImagePlugin, but I haven't tried it.

I put the EO1-ALI images from Earth Observatory online, in WMS and TMS,
with the coordinates included in the GeoTiff files.

Apparently, they were not georeferenced in relation to ground control
points, but with the imagery layer shift option included in Josm, it is
not too difficult to align them to existing data. For example, a shift
of "197; -514" quickly adjusted over Venise-en-Québec seems to give a
reasonable alignment in other areas of the images too.

We could try to improve the georeferencing of the original images with
ground control points, but for now it seems that having a try at mapping
the flood extent with the current setup has higher priority. Let me know
if you think more work on georeferencing would be useful.


URLs:

For the natural color image in TMS (recommended over WMS), use the
following link in Josm:
tms:http://osm.arkemie.org/cgi-bin/tiles/1.0.0/hautrichelieu_coulnat/{zoom}/{x}/{y}.jpg

For the shortwave infrared image in TMS:
tms:http://osm.arkemie.org/cgi-bin/tiles/1.0.0/hautrichelieu_swir/{zoom}/{x}/{y}.jpg


The base WMS URL is :
http://osm.arkemie.org/cgi-bin/osm_wms?map=/mapsite/hautrichelieu.map

Thus, for the natural color image in WMS, use the following link in Josm:
wms:http://osm.arkemie.org/cgi-bin/osm_wms?map=/mapsite/hautrichelieu.map&FORMAT=image/jpeg&VERSION=1.1.1&SERVICE=WMS&REQUEST=GetMap&Layers=hautrichelieu20110508_natcol&

For the shortwave infrared image in WMS:
wms:http://osm.arkemie.org/cgi-bin/osm_wms?map=/mapsite/hautrichelieu.map&FORMAT=image/jpeg&VERSION=1.1.1&SERVICE=WMS&REQUEST=GetMap&Layers=hautrichelieu20110508_swir&


Now on to OSM-style-collaborative-iterative flood extent mapping,
without - and probably then with - boots :)

Best wishes,

Jean-Guilhem


Le 28/05/2011 05:53, Daniel Begin a écrit :
>
> Hi all,
>
>  
>
> I've tried to "put my boots on the ground" without  going there !-).
>  I found a pretty clear satellite image of the river at its max level
> (30-31m) - which doesn't really changed since ...
>
>  
>
> http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=50577
>
>  
>
> I made few geometric adjustments to the image and compare the result
> with 30m GeoBase and SRTM contours. Geobase contours gives better
> results between St-Jean and L'Île aux Noix but from there to the US
> boundary, neither GeoBase nor SRTM is right.
>
>  
>
> I'm trying to produce a flooded area from DEM data while I'm looking
> at an image that contains what I'm looking for - the flooded area! 
> Why not mapping from it? I understand the image can be used -
> http://earthobservatory.nasa.gov/ImageUse/
>
>  
>
> Any idea on how I can use this GeoTiff image in JOSM?
>
>  
>
> Cheers,
>
> Daniel
>
>  
>
>  
>
> ------------------------------------------------------------------------
>


-- 
pgp 0x5939EAE2

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/hot/attachments/20110528/e9631339/attachment.html>


More information about the HOT mailing list