perlfu / open-habitats

-- Open Habitats 

This is research code for synthesizing habitats polygons using open data
from EU Corine and OpenStreetMap.  This produces output similar to the
commercial Land Cover Map 2007 (LCM2007) dataset, but free of license
restrictions.  This is significant if you want to distribute the data
as part of a web application.


-- Installation

This assumes the underlying system is using Ubuntu 12.04.4 LTS.

# install tools
sudo apt-get install postgis
sudo apt-get install python-shapely
sudo apt-get install spatialite-bin
sudo apt-get install python-pyproj
sudo apt-get install osm2pgsql

# setup database
sudo -u postgres -i
> createuser <user>
> createdb -E UTF8 -O <user> gis
> createlang plpgsql gis

psql gis
> \i /usr/share/postgresql/9.1/contrib/postgis-1.5/spatial_ref_sys.sql
> \i clc.sql
> \i habitats.sql

# acquire OpenStreetMap data for area of interest
# e.g. wget 'http://download.geofabrik.de/europe/great-britain-latest.osm.pbf'
osm2pgsql -C 20000 -d gis -k great-britain-latest.osm.pbf

# acquire and decompress EU Corine (clc06_spatialite.rar)
# http://www.eea.europa.eu/data-and-maps/data/clc-2006-vector-data-version-3
./load-corine.py clc2006_rel16.sqlite

# break down the Corine polygons to allow tractable queries
./tile-corine.py

# sample grid points for Corine and OSM
./compute-grid.py corine
./compute-grid.py osm

# compute the integral of the samples
./compute-grid.py route data.routing

# build base polygons from grid samples
gcc -O2 -Wall route.c -o route
./route data.routing > data.polygons

# import polygons to database
./build-polygons.py data.polygons

# merge smaller polygons to form more
./merge-habitats.py

# compute connections between habitats
./connect-habitats.py

# render habitat polygons to JSON for use in web tools
./output-habitats.py result.js


-- LCM 2007 import and verification

If you have access to LCM 2007 you can verify the similarity of the open data
derivative against it.  This is typically about 80-90%.

Import:
 shp2pgsql -s 4326 -I -S -p LCM2007_polygon | psql gis
 shp2pgsql -s 4326 -S -a LCM2007_polygon | psql gis

Verify
 ./compute-grid.py verify


-- Tuning

For tweaking the polygon merge process the whole import does not need
to be performed again.

Independent steps:
1.
  psql> UPDATE cell SET category = NULL;
  ./compute-grid.py osm
2.
  ./compute-grid.py route data.routing
  ./route data.routing > data.polygons
3.
  psql> DELETE FROM habitat_raw;
  ./build-polygons.py data.polygons
4.
  psql> DELETE FROM habitat;
  ./merge-habitats.py
5.
  psql> DELETE FROM habitat_link;
  ./connect-habitats.py
6.
  ./output-habitats.py result.js