Terrain Correction and deformations/artifacts

Microwave Toolbox
#1

Hello everyone,

I’m trying to do the geocoding using terrain correction.
I have just a problem related to a strange deformation in the area where there are mountains (or in general areas with a high elevation).

If I use the Ellipsoid Correction I don’t have this problem but If I export the geocoded image in a format readable by a third part software like Google Earth or QGIS (KMZ or GeoTIFF) it results shifted on the left.

So, the only way to have an image perfectly geocoded is the Terrain correction but I have that annoying deformation/artifact.
What can I do?

#2

can you please share a screenshot of this offset?

Please try to directly open the img file in the data folder of the terrain corrected product in QGIS (without export to GeoTiff) to check if it already has this offset.

#3

Thank you very much for your reply.

The geocoded image obtained from Terrain correction:

tc
tc1965×1128 1.14 MB

As you can note, this image matches perfectly with the map (see the lake in the blue box)
However, there are artifacts as shown in the red box.

While the geocoded image obtained from the Ellipsoid Correction:

ec
ec1948×1128 1.09 MB

There are no artifacts (see red box) but it is shifted on the left (see blue box).

#4

this is the nature of terrain correction. Range Doppler TC uses a DEM to shift pixels at their correct locations, but at the cost of these artifacts, because no image information was collected in areas of foreshortening, overlay and shadow. There is no way to restore these pixels.

Ellipsoid correction assumes a flat surface, but is not able to put image pixels in mountainous areas at their correct location.

#5

Thank you very much for the explanation :slight_smile:
However, is there a way to solve this problem? (also using another software)