Back-Geocoding fails with “Entire image is outside of SRTM valid area” when using Copernicus 30 m DEM in esa_snappy

Microwave Toolbox
1

I’m trying to run Back-Geocoding in Python using snappy (SNAP 12.0) with the Copernicus 30 m Global DEM, but I keep getting this error:

RuntimeError: org.esa.snap.core.gpf.OperatorException:
Entire image is outside of SRTM valid area.
Please use another DEM.

However, the AOI is in northern Norway (around Alta, 69° N) — well within Copernicus DEM coverage.

Here’s the relevant Python snippet:

from esa_snappy import GPF, HashMap

coreg_params = HashMap()
coreg_params.put(“DEMName”, “Copernicus 30m Global DEM”)
coreg_params.put(“DEMResamplingMethod”, “BILINEAR_INTERPOLATION”)
coreg_params.put(“ResamplingType”, “BILINEAR_INTERPOLATION”)
coreg_params.put(“MaskOutAreaWithoutElevation”, True)
coreg_params.put(“OutputDerampAndDemodPhase”, False)
coreg_params.put(“DisableReramp”, False)

coreg = GPF.createProduct(“Back-Geocoding”, coreg_params, [orbit_2, orbit_1])

SNAP desktop work as expected.

Thanks in advance!
Pritimoy Podder

2

@dolaf, could you please have a look?

3

Hi,

I doubt that this issue is related to the use of Python or esa_snappy.

To reproduce and investigate the problem, could you please provide a bit more information:

  • your full Python script to better understand, e.g., what is orbit_2, orbit_1?
  • the input product(s) you are using
  • What is the corresponding workflow in SNAP desktop which you say ‘works as expected’?

Many thanks,
Olaf