SNAP - StaMPS Workflow Documentation

Have a look here

I got it. So export_res_3 corresponds to the mean velocity. I realized also that PS point no. in StaMPS Visualizer is PS point no. + 2 in the csv file (i.e., PS point no. 100 in StaMPS Visualizer is cell number 102 in csv).

Thank you again!

1 Like

Hi, @ABraun and @mdelgado! Just a quick question. I was trying to find the answer in some posts here but I don’t remember where I saw the same problem I have now.

I got one pair (from 60 pairs in total) with zero mean amplitude prior to launching matlab for PSI analysis with StaMPS. I proceeded and adjusted some parameters, and executed step 1. I got an error. I suspect it’s because of that pair with zero mean amplitude.

What I did is to remove that pair from the analysis. The PSI analysis was successfully completed. Was it okay to delete that pair with zero mean amplitude?

Thanks in advance!

I believe so, you got a very good representation of 59 images. 1/60 is fine.
You could also had tried to re-process it.
But delete it is fine.

I agree with @mdelgado, the topic you are looking for was discussed e.g. here

and here

If there are more cases of zero mean amplitude it is worth redoing the preprocessing in SNAP, this always solved the issue. I highly recommend checking the results after each preprocessing step to figure out such problems, since they often appear in the first steps.

Hi, @mdelgado and @thho!

Thank you for your immediate response. I’ve only checked a few interferograms in SNAP before the stamps_export through the snap2stamps tool.

I am tempted to redo it actually but I noticed that towards the end of the coregistration and interferogram generation process, it takes more than 4 hrs to finish 1 pair. In the early part of it, it’s relatively fast. I can redo it but I am sharing the PC with another person who uses the same PC for his own research also.

Anyway, thank you again!

Stay safe and healthy always.

PS: Fortunately, that pair that I removed is quite distant from the main event.

1 Like

If it is only one ifg, it might not influence the StaMPS process so much.

However, concerning your processing problem:

  • Check if you can increase the RAM that can be used by SNAP Increase snappy memory (beginner) snap2stamps uses the gpt API of SNAP, check out the snap2stamps Manual 1.1 Installation in order to set up the memory for gpt

  • If possible, write the outputs to a SSD, for me that really made a significant difference in processing

I did modify the gpt.vmoptions also in snap. I just wonder where can I find the snappy folder? I am not familiar with this one to be honest.

please have a look at my last post, I edited it since you are right gpt should do, snappy is not used, as far as I see. If @mdelgado can confirm would be great.

If this is the case, I know where to look for it. As I have mentioned, I’ve modified it following the one recommended in the snap2stamps manual.

Even the splitting part takes too long also when it progresses.

Thank you again.

Confirm that snap2stamps does not uses snappy, but some python wrappers that execute gpt with the customised xml graphs

1 Like

Hi!

Can anyone please give me a reference to cite for pre-processing of SAR data before and up to using snap2stamps?

Thank you!

how about this one? https://gitlab.com/Rexthor/gis-blog/-/blob/master/StaMPS/2_stamps_workflow.md

I don’t think there is any official, scientific or peer-reviewed reference you could use.

I think this should work. I just want to include in my thesis. I did not see any name of the author/developer. What name should I use for this citation?

Thank you!

I’ll send you a private message.

Sure there are as stating here: https://zenodo.org/record/1322353#.Xyk2BUUzY2w

When using this software package please reference to this DOI (doi:10.5281/zenodo.1322353 ) and to the paper: M. Foumelis, J. M. Delgado Blasco, Y-L. Desnos, M. Engdahl, D. Fernandez, L. Veci, J. Lu and C. Wong. “ESA SNAP - StaMPS Integrated processing for Sentinel-1 Persistent Scatterer Interferometry”. IEEE International Geoscience and Remote Sensing Symposium. IGARSS 2018.

You may also add the reference to my zenodo:

Zenodo citation:
Jose Manuel Delgado Blasco, & Michael Foumelis. (2018, July 27). Automated SNAP Sentinel-1 DInSAR processing for StaMPS PSI with open source tools (Version 1.0.1). Zenodo. http://doi.org/10.5281/zenodo.1322353

Thanks

Hi!

I had already cited Foumelis et al., (2018) in my thesis, but since the deadline was approaching, I had already submitted it before your reply. Sorry…

I would like to thank this forum for all the invaluable help and guidance everyone provided to a new-comer and inexperienced person like me. I could never have completed my thesis without your help!

Regards,

Ninad

1 Like

hi and thank you very much to the SNAPtoSTamPS developer,

I am carrying out InSAR analyzes in the city of Rome but I would like to increase the quality of the processing. (PS, SNAPtoSTamPS)

To improve the analysis I would like to be able to use an external dem such as DEM-EU or LIDAR DEM.

how can I insert an external DEM (such as DEM EU or LIDAR) within the processing?

thank you very much for the helpfulness of the developers

FM

what are your exact aims with the external DEM? Can you please clarify how it helps to increase the quality of the analysis?

I think having a higher resolution dem than the SRTM 1 can bring better coregistration. I have often seen that in many elaborations DEMs at 5 meters are used. I guess

thanks

FM