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In one of my projects I need to digitize video clips showing some natural landscape. Specifically I need to know distances between different areas and elevation levels.

I have a topographic map of the area so distances are not a problem.

Is there any tool / library that allows to create DEM from a common topographic map? A language of the library doesn't matter, but I prefer open source solutions if possible.

I know about QGIS and GRASS, but I cannot found how to use them for this specific purpose.

EDIT: My map looks like this: enter image description here

Flot2011
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  • What do you mean by a common topographic map? You mean a chart with roads, rivers, grid lines and height either shown by contour lines mixed in with all that or fancy hill shading? – Spacedman May 25 '13 at 23:51
  • Where in the world is your map from? Can you not just download a DEM for your area of interest? – blah238 May 26 '13 at 01:06
  • @Spacedman: yes, the chart with contour lines. – Flot2011 May 26 '13 at 07:20
  • @blah238: the users provide the maps as an input data for my program. I just don't want to send them to download DEMs, I cannot also guarantee that there always be a DEM for their specific region. I prefer very much to automate the process. – Flot2011 May 26 '13 at 07:30
  • Can you upload here or point us to a typical sample map image? Because I suspect the answer is 'no chance'. – Spacedman May 26 '13 at 08:02
  • @Spacedman: look on my edited answer. – Flot2011 May 26 '13 at 09:35
  • As I suspected, 'no chance'. Any program would have to first extract and follow all the contour lines from the pixels, then figure out the height of each line by following it to the nearest number (which sits across the line, breaking it), dealing with the breaks in contour lines where they go into gullies etc. No chance. – Spacedman May 26 '13 at 09:44
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    If you are okay with 30m resolution you could download the entire ASTER Global DEM V2. – blah238 May 26 '13 at 20:09
  • You could get the source data for the topos, and as long as they are geo-referenced, use them as underlying data. For instance, in Canada we have the toporama product derived form the canvec data. So any map they bring you, check the extents from the data or metadata, and make a DEM in the background from the source data, for that extent. – Tom May 27 '13 at 06:09
  • @Tom: Sorry for my ignorance, I am a newbie in th field, but what tool do you use for DEM creating? – Flot2011 May 27 '13 at 09:43
  • @Flot2011 You could use QGIS for this, making the DEM from the contours: http://gis.stackexchange.com/questions/18116/is-it-possible-to-make-a-dem-from-contours-in-qgis – Tom May 28 '13 at 03:57

2 Answers2

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If you are okay with 30-meter resolution, instead of attempting to extract a DEM from a topographic map, you could try downloading the entire ASTER Global DEM. See this question for more information:

Community
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blah238
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Try this tool, http://freegeographytools.com/2009/3dem-website-is-gone-but-3dem-still-available-here unless you have ArcGIS available. You will need to download a DEM of your area. This tool is just a simple way to get an animation. You could export as VRML and use a browser based VRML viewer to do a fly through. You can overlay your map to the DEM as long as it has a georeferenced for a GIS. You probably can get a digital copy by searching around that is suitable for a GIS.

lewis
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