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This error is explained in http://stackoverflow.com/questions/21529194/ , with solution in How to get rid of deprecated conversion from string constant to ‘char*’ warnings in GCC? , aka, it need to pass -Wno-write-strings to g++: Install mdenoise on linux: mkdir -p ./scripts curl -L -C - 'http://www.cs.cf.ac.uk/meshfiltering/index_files/Doc/mdsource.zip' ...


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A tool that can do this (among others) is the Sky-View Factor Based Visualization (http://iaps.zrc-sazu.si/en/svf#v). Calculate several parameters of a terrain. Is damn good.


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The Hillshade tool inherits cell sizes from the raster layer it is based on. If you are able to recreate this DEM using a smaller cell size, the resulting hillshade should also have smaller cells.


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gdal + convert based workflow There is a gdal + convert solution which gives good visual results. The trouble with this solution is that convert destroys geographic informations which you then have to restore. It increase the number of action to run. # Basic crop gdal_translate -projwin 67 35.92 99 5 ../data/noaa/ETOPO1_Ice_g_geotiff.tif crop_xl.tmp.tif # ...


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For my case (hillshade and my computer), I had to use --calc="(A/3+B/3+C/3)" to get a correct average results. (A+B+C)/3 fails because gdal_calc limit the equation to a [0-255] range. (A+B+C)/3 will first calculate A+B+C modulo 256, then divide this value (in range [0-255]) by 3, giving a low value and dark output. For more on gdal_calc operators, see ...


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Gdal_calc's numpy seems to have more operators : + addition - subtraction / division * multiplication = equals to < less than > larger than ! not equal to ? if clause M maximum of two values m minimum of two values B bit level operator I haven't found clear and proper examples for how the exotic operators should be used. If you have ...


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The linked source mention "change its fusion mode to < Multiply >", so the operation to do is not a simple average of input hillshades (for this, see also How to average gdal_hillshades?). It's something else. Yet, let's create the 3 different-sunlight-directions hillshades : gdaldem hillshade input.tif hillshades_A.tmp.tif -s 111120 -z 5 -az 315 -alt 60 ...


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Nutshell Each set of 3 images below should be read such as "grey (band) + opacity (band) = transparent result". You can test these processes within minutes via the associated github hosted makefile. Process #3 is the one which I recommend, with a threshold between 170 (keeps strong shadows) and 220 (keeps all shadows). Process 3 provides the strongest ...


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First, use gdal_calc.py to invert the band : gdal_calc.py -A Shadedrelief.tif --outfile=InvertedShadedrelief.tif --calc="255-A" gdalbuildvrt helps to merge 2 files into a two band image (or a 2 band vrt), it takes the first band of each input into band 1 and band 2: gdalbuildvrt -separate final.vrt Shadedrelief.tif InvertedShadedrelief.tif ...


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The isoline paper maps are usually the cheapest and quite often the only available sources of information on the spatial pattern of terrain altitude, rain intensity, snow depth and many other phenomenon. Unfortunately “…interpolating digitized contours to a regular grid can result in the creation of severe artefacts in this resulting surface. Curiously ...


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Hillshade computes the local illumination from a light source located at infinity (like the sun). Basically, it yields the cosinus of the normal to the face of the terrain and the light ray. This can be used for : visualisation and cartography : the light source is then located near the north, which then gives a nice picture of the relief. analysis ...



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