Upload
gustavo-delgado
View
227
Download
0
Tags:
Embed Size (px)
DESCRIPTION
manual
Citation preview
Topic: Geocoding maps from articles
By M. Neteler, FEM-PGIS: http://gis.cri.fmach.it/
PostGISomics
First step: Scanning the map or copying it from a PDF article
Copy map to file (PNG format)
Second step: Download and install a free GIS – Quantum QGIS
http://www.qgis.org
- Set LatLong/WGS84 as projection- Load ISTAT map of provinces or other maps
Third step: Geocoding of unreferenced map 1. Georeferencer tool
2. Load file from PDF
4. Digitize Ground control Points (see next slide)
3. Run geotool in order to digitize points
Fourth step: Geocoding of unreferenced map II
5. Digitize Ground control Points (GCPs) (see next slide)
6. Set GCP from map
Digitizing rules:- use province corners as reference or other distinct features- well distribute ~10 points over the map
Here the coordinates will appear...
Fifth step: Create new vector map to store the WNV points
You can of coursealso add morecolumns in order tosave further attributes.
Sixth step: Enter name for empty vector map (SHAPE format, .shp)
Seventh step: Digitize points
Enter ID, save
Eighth step: Toggle editing to stop/restart editing, save vector map.
Enjoy !! :)
Editing toolbar
Toggle editing on/off
You can of course reload and modify in QGIS.
You may wantto save allas “QGIS project”