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dSARsim documentation


Basic principles


dSARsim doesn't need actually an "installation" procedure. It needs a python 3.x environment with the right modules and then it can be just downloaded and run. As stated in the README file, the needed modules are:

  • sys
  • math
  • copy
  • argparse
  • numpy
  • scipy.ndimage
  • osgeo.gdal
  • multiprocessing.Pool (not necessary but needed for parallel computation)


In the following you can find a description of the parameters of dSARsim. If you want to see some usage examples go to the dedicated page.

-h, --help
       show help message and exit.

-i INPUT, --input INPUT
       input DTM/DSM image (32 bit floating-point GeoTIFF image in UTM coordinates). If the image does not contain pixel size information, dSARsim assumes the pixel spacing is equal to 1 m.

-o OUTPUT, --output OUTPUT
       output image (same format as input).

       SAR incidence angle in degrees. Default is 30.

       angle wrt the North-South axis. aspect angle > 0 = clockwise. Default is 0.

       spacing between azimuth pixels in the output image in meters, or 0 if automatically set as the same spacing of the input DTM/DSM. Default is 0.

       spacing between slant range pixels in the output image in meters, or 0 if automatically calculated in order to obtain a flat-terrain-'ground range' simulation. Default is 0.

-d {w,e}, --direction {w,e}
       direction of view of the sensor. 'w' = West to East, 'e' = East to West (assuming the sensor going from North to South with aspect angle = 0). Default is 'w'.

       no data value used in the DTM/DSM image, if any. Default is -9999.

-r, --rotateBack
       if aspect angle != 0, rotate back output image by -aspect angle degrees. Use only if azimuthPixelSpacing and slantRangePixelSpacing are not set by user in order to get simulations directly comparable to input DTM/DSM. Default is not set.

       number of concurrent threads to be run (works only if the module multiprocessing is installed). Default is 1.

       debug mode. Default is not set.

-v, --version
       show program's version number and exit.

Basic principles

dSARsim is based on simple geometrical rules and doesn't simulate scene radiometry. A more detailed description of the simulation process can be found in the GitHub repository here. The same document in PDF format can be downloaded here. Have a nice reading!