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Is it possible, to correct a raster DEM by changeing the raster-cell-values manually, like by "painting"?

My DEM (ASTER) have one small error where the elevation is about 300m below the actual elevation. It should be a hill, and not a hole...

SRTM 4.1 is good, but has other errors (the hill is very steep and small, so SRTM "ignores" it (<90m).

enter image description here

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In this question, it looks like you are referring to the fact that there is a steep hill or spire, inside the circle of your 3125 contour, that is not shown on your DEM. If this is the case, I would hesitate to call it an error. If a feature is too small to be captured within the stated resolution of a dataset, it doesn't make the data wrong. The DEM is correct based on the stated parameters of how it was created. –  Get Spatial May 31 '12 at 0:47
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2 Answers

up vote 10 down vote accepted

Yes, in GRASS you can edit raster cells graphically with d.rast.edit.

Raster cell editor in GRASS 7

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I hesitate to mention this because markusN's answer is so good. But if you don't get on with GRASS and if your DEM is not too large you could try the following.

Firstly, note the coordinates for the pixels that you wish to edit. Then explode the DEM to xyz triplets using gdal2xyz:

gdal2xyz.py input_dem.tif output.csv

'output.csv' will be a space delimited text file containing the xyz triplets.

Next, load 'output.csv' into a plain text editor, search to find the coordinates and change their z-values as required. Save the file, then convert it to a DEM TIF using gdal_translate:

gdal_translate output.csv new_dem.tif

Nick.

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