[HOT] Re : RDC-Congo Pre-Activation : Lac Kivu

Andrew Buck andrew.r.buck at gmail.com
Tue Dec 11 15:32:56 GMT 2012


The buildings to the south of Sake are beginning to look very good.  I
have been doing some further building mapping around the central part
of Goma and that is coming along nicely.

I have found quite a few old US Army maps (and other assorted public
domain maps) of the area on the Perry-Castañeda Library Map
Collection.  See the full list of maps available here:

http://www.lib.utexas.edu/maps/zaire.html



In addition to tracing buildings, I have begun to sort through this
list of maps and begun to orthorectify the ones that are the most
useful.  Although the maps have grid lines on them that in theory
should be enough to perfectly orthorectify the images, however I have
found that the maps are not that good in terms of absolute positional
data but they are good from a relative standpoint and contain a lot of
POI data and other useful things like elevations of mountain peaks and
whatnot.  There are also some 1:7500 scale maps from the mid 1990s
with buldings and even a few POIs like hotels, banks, etc.  These
1:7500 scale maps are avaliable for several cities in the congo so I
plan to upload these as well.  With this in mind, I have been fitting
the ground control points to the actual map features (roads, rivers,
etc) to the OSM data.  This makes for a much better "fit" that nearly
removes any spatial incaccuracy in the maps due to the limited
surveying available at the time they were made.  You can see all the
maps I upload at the link below, for now it will be mostly further
maps of the area we are currently working in, but I can work on any
ones available if people have requests.

http://mapwarper.net/users/82/maps

AndrewBuck



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