How to prepare Sentinel-1 images stack for PSI/SBAS in SNAP

Hello, I saw the following picture in the mt_prep_snap script

Can snap now do data preprocessing for SBAS based on StaMPS?
(Note: The information I found in this forum is that snap7 cannot implement SBAS data preprocessing)

SNAP does currently not support stacks with multiple masters, but this is planned for future releases.

I met a question,when i use the function of time series plot in StaMPS.2020-04-12 12-36-18屏幕截图
it said there is an undefined function in ts_plot.m.
when i click the button "TS plot "in the graph,it only display the points resampled around one selected without the picture for time series of the point.

just showed above.
this is the code i followed here.

who can tell me what should i do?thanks.


I am trying to download this file but it said file does not exist. can you share it again

Is it possible to process all the three sub-swaths at once by changing this parameter in project.conf?


The file is no longer available, please check the instructions here: About the StaMPS category

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I am really stuck here. I need to process all the subswath together. Can it be possible by using IW1=IW2=IW3?

the current version of snap2stamps can only process one swath at a time, so these are the possible inputs:

  • IW1=IW1
  • IW1=IW2
  • IW1=IW3
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Okay Thankyou @ABraun

Good afternoon everyone,

I hope everyone is well, I would like to ask you a question that intrigues me. In any time series with PSI or SBAS (or time series in general), what happens when the result is in m/year but my images only cover 4 months? Is the total deformation result divided into 12 months (one year)? because in that case it would not be representative. I don’t know if it is well understood, but it has me very intrigued and I don’t know if it depends on each software or is part of a common methodology.

Thanks for any reply!

Unless your AOI suffers a very strong subsidence/uplift such as Mexico CIty (subsidence) or Campi Flegrei (currently uplifting) with large rates, I would not suggest to analyse only 4 months of data, as your results could be showing a seasonal effect and you could interpret it as long term deformation.

My suggestion and having the large availability of satellite data nowadays, or getting larger dataset.

Still, regarding your question normally results are in mm/yr / cm/yr

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Thank you very much for your reply. I just wish I could ask two more questions related to this:

1.- For a monitoring of subsidence or uprisings (in general), is a year of analysis recommended? (with 15-20 images for each Ascending and Descending)-

2.- In the case of having 4 months of study and the deformation of the result is, for example, 30 mm / yr. This means that there was a deformation, for example, of 120 mm / yr? and having only 4 months of study, was divided by 12 (one year) to calculate mm / yr, understanding that 30 mm / yr equals 30mm for one year? I’m sorry for the confusion I may have, but it kind of made me dizzy.

Thanks for your reply

Regardless of the investigated time (e.g. 4 months), the result is given in mm/year, so you can compare it, but this assumes that the movement observed is constant over the entire year.
Therefore, it is better to distribute all images over a longer time span, so you can identify eventual changes in the deformation rate.


Use several years to get long term phenomenon, otherwise you could see only seasonal effect for a year and not trends in deformation

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Dear Abraun,

Thank you very much for your reply, as always. I will incorporate it into my future studies.

Best regards

Dear mdelgado,

Thank you very much for your reply. I will consider at least two years in my next PSI or SBAS studies.

Best regards

hi,all the initial_baseline=0,seems something wrong with I run stamps(1,1)

Hello, I am trying to export results into Windows to be able to plot the data using acsii files in another software which is very handy, 3DField. When I type ps_output in matlab, it gives only ps_u-dm data for each interferogram in ascii file. But, instead, I would like to get ps_u-dms data in ascii file for each ifg since this seem to give me more smoothed and hence presumably more accurate results.

Could anyone help me how to generate u-dms output in ascii file?

I assume all ps_u-dm and ps_u-dms or even ps_u-dmo files generate displacement results for each point in mm. Am I understanding this correctly?

Any help here would be greatly appreciated!

PS: Screenshots from matlab of ps_plot(‘u-dm’), ps_plot(‘u-dms’) and ps_plot(‘u-dmo’) are provided below for comparison of the results.

The study area is an oilfield with subsidence. Empty area in the center is a trace of river and in the south-east is a trace of sandy desert. Persistent blue areas are where the cluster of production wells, in the center and in the north-east. Persistent red area in the west - I have no idea, this zone is outside the area of oilfield.

hello every one am waiting your help
since am facing a problem running stamp(2,2)
error in ps parms default (line 94)
error in getparm line 14
error stamps line 53


Thanks for the topic, its help me alot. But i have some problem with the result, it seem to be moved long distance to the east.
I checked the dataset and found that something wrong with the orthorectifiedLon!
The dataset has the min-lat: 105.55 deg and max-lat: 105.98
But the orthorectifiedLon band has the min-lat:105.75 and the max-lat: 106.17
Help me, please!