I'm building a virtual 3D terrain scenery using both satellite imagery (google maps satellite) and elevation data from GDEM Aster elevation data (geoTIFF format files).

My problem is that the elevation data does not perfectly match the satellite images. For example, on some small coastal zones, the sea actually reaches the top of some cliffs...

So I'm desperately looking for a way to manually correct the GDEM Aster elevation data (geoTIFF format files) for these zones. I tried using different photo editing software (trial versions and free versions) but none of them lets you set signed or unsigned 16 bit values to individual cells. Even though they are perfectly capable of processing 16 bit grayscale images, they only allow you to set 8 bit values (0-255) in their respective color pickers... I tried : Photoshop CS5, Photoline,, Picture window Pro Paint shop pro 10, Gimp 2

Any info on any software (Windows) that allows to do this would be appreciated.

P.S. I already use Geotiff tools to save and restore the geographic metadata.

  • Maybe, you can try Python or Matlab? But you will see there the matrix, not image.
    – nadya
    Commented Oct 28, 2012 at 18:36
  • Thank you Nadya for your answer. I'd like to do this graphically. I would have to learn Python and/or Matlab, and doing that programmatically will take me ages...
    – Axel
    Commented Oct 30, 2012 at 8:50
  • This question appears to no longer be of interest to the original asker (who has not been seen on the site for 9 months) or the community (who have not answered or commented for 9 months).
    – PolyGeo
    Commented Sep 26, 2013 at 13:43
  • @PolyGeo Nevertheless the question appears to remain valid and on-topic. Although I have a problem with its assumptions--manual correction of elevation data to match a photo seems misguided and inverted to me (the correction should be done reproducibly in a controlled manner and it should be applied to the photo, not the DEM)--it's not an unusual request and could benefit from a thoughtful answer by an experienced GIS or image analyst.
    – whuber
    Commented Sep 26, 2013 at 14:43
  • @whuber your call will be much more informed than mine on this Question so I am thus happy to see it left open.
    – PolyGeo
    Commented Sep 26, 2013 at 14:49

2 Answers 2


Take a look at Daylon Leveler: http://www.daylongraphics.com/products/leveller/

  • Hello, Thank you for your answer. Leveller "looks" interesting but they do not have a trial version, and that is a no-go for me. I will not buy something I cannot try first. I've been very disappointed in the past with products that I had to buy before being able to try. I hate throwing money out of the window. Best regards.
    – Axel
    Commented Oct 30, 2012 at 8:41

I also was looking for pixel editing tools some time ago, and found a couple of things.

The paper Manual Raster Editing in Erdas Imagine (pdf) describes some pixel values editing methods.

And there is the Raster Editor toolbar for ArcGIS > 9.0.

Hope they will be good for your DEM.

Also, these two questions Change one pixel and Manually edit a raster describe the similar problem, and the suggestion was to create vector, rasterize and merge with your raster.

  • Hello, Thank you for your answer. I do not have ARCGis to use the Raster Edition Toolbar, and even though I cannot put my hands on pricing information it's certainly waaaay too expensive for the use I'm going to make of it. I retrieved from an old DVD of mine a copy of a software called "Wilbur", that seems to do the job, but crashes on me when I try to save the modified work... I also first have to convert the Geotiff file to PNG. I think the files I try to work on are too large for it (3601x3601 pixels). Best regards
    – Axel
    Commented Oct 30, 2012 at 8:42
  • Your second suggestion is too complicated. I do not understand why there isn't some simple software or image editing program that lets you do "TRUE" 16 bit grayscale pixel by pixel editing ?
    – Axel
    Commented Oct 30, 2012 at 8:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.