Using Sentinel-1 SLC bursts with MultiMasterInSar

Hello,

As full Sentinel-1 SLC images are quite large, I hope to use SLC bursts for my processing chain.
At the moment, with the full images, I use
TopSARSplit->ApplyOrbit->BackGeocoding->ESD->Deburst->Elevation->Subset->MultiMasterInSAR
to extract & process the burst(s) I’m interested in processing and it works fine.

To avoid the 4.5GB download for a simple burst, I decided to use the new burst products (made available through either ASF or CDSE)

This required me to modify my processing chain by removing the TopSARSplit step which is expected as I already have my desired bursts.

The remainder of the chain works fine until I get to the MultiMasterInSAR step.
Here the step fails with an error message:

java.lang.IllegalArgumentException: expression: Undefined symbol ‘i_ifg_’.

(this happens with both SNAP 12 as well as SNAP 11)

This is with a stack of 1 master burst and a small number of slave images (3-5 in my tests so far)

Interestingly, if I apply the normal Interferogram processing step it does process the stack of master and slave images fine. But unfortunately, I need the full set of image pairs, not just the individual master/slave combinations.

This happens with bursts retrieved from ASF and converted to the SAFE format using burst2safe as well as bursts retrieved using the eu-cdse utilities.

Does anyone have any idea what might cause this and how to fix this?

Thank you very much in advance!
Steve

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Someone else encountered this problem in a different scenario(reported in Snap->Problem Reports) and noted that snap 9 does work.
So I downgraded to snap 9 and can confirm that it does process the stack fine.
So something must have changed in the later versions of MultiMasterInSAR which fails.

@jun_lu can you have a look?
Thank you

We’ll be adding better support for single burst products soon

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That’s great!
Is there any sort of timeline when we will see this functionality?
I’m happy to test any beta version of it as well.

Has anyone try this again on SNAP13?

I did try it , but the error remained. Can you point me to any help user manual that help how to use the MultiMaster Stack and MultiMaster InSAR successfully?