SNAP+StaMPS ERS1/2

duan · July 25, 2019, 2:22pm

Hi,

I always got the following problems when I use SNAP as the pre-processor for StaMPS for ERS1/2 data.
I used 4 pairs here.

Can you help me solve these problems?
Thanks very much!

Dingfeng Duan

mdelgado · July 25, 2019, 8:48pm

I think you got the master-master pair as a interferogram or something similar.
Still… please provide more information if you want us to be able to help you…
Otherwise it is more difficult …

duan · July 25, 2019, 11:52pm

Dear Sir,

Thank you!
I don’t have the master-master pair.
I do the ApplyOrbit, Coregistration, Interferogram, and Export to StaMPS in SNAP, no matter version 6.0 and 7.0. Then I got those folders: dem, diff0, geo, and rslc:

After issue the command “mt_prep_snap”, I got the several patches, for example:

It is strange that some files are empty!

Then, I got the error in stamps(1,1).

Thanks again for your help!

Yours,
Dingfeng Duan

mdelgado · July 26, 2019, 8:55am

Could you please check the interferograms and the rslc images before running mt_prep_snap?

I am afraid that you got some corrupted files that affects the consecutive steps

duan · July 26, 2019, 12:09pm

OK.
I will try.
Thanks!

duan · August 3, 2019, 7:20am

Hello, Sir,

I am sorry to reply at such a late time.
I checked all the steps, I found that there are always NaN values after ApplyOrbit and Coregistration (Processed with SNAP).

No matter it is ERS 1/2 or ASAR.

Can you help me solve this problem?
Thank you very much!

ABraun · August 3, 2019, 8:11am

that means the coregistration failed for this product.

are all images from the same track?

duan · August 3, 2019, 8:25am

Yes. They are from the same track.

mdelgado · August 5, 2019, 8:13am

Are the ERS images in N1 format or CEOS?
If the former, which is their exact extension? .N1? .E1? or .E2?

I found in the past issues where the extension for ERS is N1 and not E1 and E2 as SNAP was expecting, exactly for the ApplyOrbit operations, as SNAP search N1 into the Envisat orbit files/repositories, and not for ERS.
Not sure if this was solved already.

duan · August 5, 2019, 11:28am

Thank you!
The extension of my ERS data is E1/E2.

So, I think there is no problem with the ApplyOrbit Operation.

mdelgado · August 5, 2019, 11:40am

Good then!

Had you seen your coregistered pairs after coregistration? Could you check it out?

duan · August 5, 2019, 11:55pm

Thanks!
I think I did that. The coregistered pairs have NaN value.

mdelgado · August 6, 2019, 5:18am

Are you then reprocessing them?
I was meaning if all their blues were NaNs, and not only if they had some.

Good luck