Does anyone have experience of converting scanned images of maps, e.g. GIF, to a GIS format. The objective is to take a map image and then overlay additional information from other sources onto it. -- Ian The Hotmail address is my spam-bin. Real mail address is iang at austonley org uk

On Jun 8, 10:42 am, Ian Goddard <[email protected]> wrote: > Does anyone have experience of converting scanned images of maps, e.g. > GIF, to a GIS format. > > The objective is to take a map image and then overlay additional > information from other sources onto it. When I did this, I used OpenLayers for the scanned images (which I had to cut up into suitable sized tiles, but that process was easily automated; I think I also converted to png which may or may not have been necessary), and then used OpenLayers.Format.GML to read/write GIS objects expressed in GML. That's given me a nice Google-like "slippy" map with a choice of base layers, including Open Street Map, the old (and out of copyright) OS NPE maps, and modern (and very definitely copyright) OS maps. On top of that I can render things like county or parish boundaries. This is part of a project I'm working -- quite gradually, must be admitted, but I do have a paid job to do too! -- to provide open source vector data for the historical boundaries of the parishes, districts, hundreds, dioceses and counties of England. Richard