I have an 8 km by 8 km raster of 20 m/pixel terrain data. The georeference data has been lost. All I know is that it's within 100 km of Smithers, BC. I realize that this might involve some very heavy raster processing, but - is there any way I could find the location by matching against existing DEM/CDED rasters in the area?

  • so the raster is raw values? That is, it's more than the coordinate system is unknown? – mkennedy Nov 2 '12 at 23:45
  • Does it have any rivers, valleys? Or well-shaped hills? Then you could try to relate it with satellite images. – nadya Nov 3 '12 at 2:10
  • It's British Columbia — it's all rivers and well-shaped hills ;-) The source data are likely from NRCan's free Geobase terrain, but translated to UTM. – scruss Nov 3 '12 at 13:00
  • Can we see the image? – Matthew Snape Nov 3 '12 at 20:02
  • If you go to 128.03982 W, 54.39992 N on the Geobase viewer, you'll see roughly what I'm looking at: geobase.ca/geobase/en/… – scruss Nov 17 '12 at 19:47

You could manually georeference to another existing DEM product (SRTM maybe, but resolution disparity would be huge). Having said that, you are better off trying to get the georeferencing info from somewhere as DEM to DEM registration when the DEMs have different resolutions is super hard. Perhaps contact the person(s) who created the original data?

  • Yes, I know this is a hard question. That's why I asked. It turns out that the metadata report that went along with this project stated the wrong UTM zone, so while that particular problem is solved for me, the general solution isn't - can terrain matching be done at all? – scruss Nov 3 '12 at 13:04

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