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

How many the total number of your images?

hi falahfakhri,

thank you for your answer, well, i just tried with 2 images but before i tried with 16 interferograms and also just with 11 interferograms but the same problem.

Using only (2) images to apply PSI is not accepted at all, this is the first point, the second issue I’d like you to do STEP BY STEP, to find out where is the error ? In Case it is occurred,

So, if it possible to increase your images to (20) images at least, it is fine, however your case 16 it is acceptable,
The second thing is apply this approach step by step ,
-Save each single item in a separate folder named by its date yyyymmdd
-Apply Split
-Apply orbit
-Backgeocoding by selecting the master to be the first one and the slaves are following,

  • Apply ESD
  • Apply Deburst (The first item is ready to by exported to StaMPS and waiting the following one…)
    -Create Interferograms starting from the ESD step,
    -Apply Deburst
  • Apply Topo phase removal (Now the second item is ready to be exported)

In each step above try up to open and check up your product,

Now, we are in StaMPS,

As our colleague @mdelgado mentioned in his post, be sure from which Version of StaMPs are you using, according to his suggestion to use

Also he mentioned an important thing

As I explained to you above, hope it is helpful,

Thank you for yours answers,
I am now trying to do again de same work, i choose just 2 images for PSI because i would like to verify where is the fault and to be sure that the first step of matlab can run. I will follow all the steps you give to me now and let you know my output.
thks

hi FalahFakhri,
i just finished the process you told me but I did it for 2 images Sentinel 1. I want to be sure from the working of the process correctly, Hellas, I got errors. the first one is: I choose just one burst but “esd” didn’t work well , I took 2 bursts and the process work well in SNAP also the export to stamps, The first script ran good in Cygwin (I think), the second one stamps(1,1) shows error as follow.


.
thks

Let me ask you a question,

What is the reason of applying stamps(1,1)? And how it works, or what is behind this script?

These questions for you to think about the scripts goal, not to answer me.

The other issue, I’m not sure about the validity of running StaMPS scripts , under cygwin, because many of other colleagues faced up this problem before , you could find their complainants using StaMPS under cygwin.

hi, I saw it in the forum that colleagues talk about difficulties of working in Cygwin environment. but that is what I have, I have no Linux , I have a windows computer. yesterday one colleague tried to install for me VM via oracle virtual Box but it didn’t succeed. i want to apply PSI approach with the materials that I have.
stamps(1,1) is used to upload all information such as computed amplitude dispersions , baselines information, heading,… in the aim to store them in a various workspaces.
but if stamps(1,1) didn’t run, I can not to go to the next step. thks

Have a look at the solution of our colleague

Hello everyone
I have a big problem that has been bothering me, just that I can’t confirm the correctness of PSINSAR.
The following figure shows the “u-dm” got by using the ps_output instruction of STAMPS, which means the amount of displacement in each time period.


I used EXCEL to list them, but found that displacement values are fluctuated at the same locate /different times .
I think it is wrong, because against local GPS data, it should be a decline, not ups and downs.GPS data like following figure.

Does anyone have any advice, I will be very thankful.

I can use ps_plot in StaMPS 4.1-beta_20180814.
I have had an excess matrix before. I remember that because there is a NAN in the ps2.m, you can replace the original STAMPS with the correction file posted in https://github.com/dbekaert/StaMPS/search?q=NAN&unscoped_q=NAN.
You can refer to https://groups.google.com/forum/#!searchin/mainsar/$20NAN|sort:date/mainsar/jG1JuPTLp1Q/Rm_YTx2bAQAJ
GOOD LUCK~

I dare to change the title, as this thread is not anymore only for SNAP 5.

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Hello @m477h145 do you solved it ? I have similar error, my Initial gamma threshold is 1.0 and i have 0 PS selected initially and 0 PS selected after re-estimation of coherence.

Thank you

Please check all the interferograms using SNAP. Normally that could be caused by one corrupted ifg

Thank you @mdelgado

After to fixed the problem, i have result, but my stack contain 5 image and 4 interferogram, i can see the result is wrong, i will process a stack with 20 image to obtain result better.

In my time series, the displacement is 800mm i dont believe it.

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Dear all,
I am using StaMPS 4.1 and I can’t run ps_plot for Sentinel-1 data because Matrix dimensions must agree. I found an error like this


Can anyone help me or give the correct matlab script specifically for sentinel 1 ?
Thankyou

Hello, @FeiLiu

To know the absolute values of displacement in PSI, ¿is it necessary to know a point (such as a level bank) from which its displacement is known with different measurement techniques such as GNSS and then make the correction to all PSI with respect to the point of reference as in the DinSAR technique?

Yes, you are right. You should have at least one ground point to konw the absolute value.

I still spend very much time at the deburst step. @katherine’s post is created in March 2017. Over time, any other solutions found to the problem? Or, do you still apply the same solution? Thank you.

Hello @mdelgado is there an opened topic about Stamps results only ? because i get lost in the discussion here between SNAP steps (preparation export …) and Stamps processing. I have some questions and results to share about PS distribution got using Sentinel-1 and Stamps but i dont know where to post it. Any suggestion please !

Not sure! Please feel free to share yours.