Carrying out InSAR processing steps externally

For a project, we are processing interferometric TerraSAR-X data. The pipeline generally works like a charm, but we would like to use a more sophisticated coherence/phase estimator than boxcar (or Goldstein). Is there any way to carry out this step externally, but to reintroduce the resulting coherence/phase images to SNAP for further processing?

To be more precise, the workflow would conceptually look something like this:

  • Image coregistration → SNAP
  • Flat earth (terrain) removal → SNAP
  • Phase/coherence estimation (e.g. using NL-InSAR or some deep learning-based solution) → external
  • Phase-to-height conversion → SNAP
  • Geocoding → SNAP
    and so on.

Or would there be a completely different solution to my desire? The whole point is to get better phase/coherence estimates into the system…

Not to be mistaken: It would be also OK for us to possibly carry out coregistration and phase/coherence estimation outside snap, and then loading the resulting images, which are possibly still in the slant range geometry of the master SLC, into SNAP. Would it be possible in that way?

OK, it seems that is not so easy… But I am downscaling my wishes. :wink:

Now a last and hopefully simple question: Is there any way to export the flat earth phase for external use?

I do not think it is possible if you just use snap software.
But all these can be done if you go deep into their java source code. You will then find they calculate the flat earth phase in blocks, you need to write some codes to get what you need…