Hi i cant solve this problem. İ think İts cause of empty interferogrmas. So that i reorganize my datasets with alib1 scripts
I have successfully finished SBAS processing, using stack of 18 Sentinel-1 images. Interestingly, results show water (a lake - see below) in my study area that has the same point density as outside of the lake, which makes me suspicious of results (with PS processing water usually has no PS):
Can anyone explain this?
Also, I am unclear on how to determine the Multilook numbers in project.conf:
Multilook
RGLOOK=?
AZLOOK=?
SMOOTH=?
There seems to be no information on how to choose appropriate numbers for these parameters anywhere. Can anyone suggest some background reading to help me understand and select decent values for these parameters?
Finally, any suggestions on how to export SBAS time series from matlab as a csv? For PS I have been using StaMPS-Visualizer, but don’t know if this can be adapted for use with SBAS.
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Hi, can anyone show the folder structure before applying sbas_snap2stamps? And what does the MASTER tag (in the configuration file) mean? Is there only one master in sbas?
Thanks.
Dear @ABraun and @dongyusen
Sorry to disturb you, my problem posted HERE are not solved yet. Can you take a see, please? I can’t find any mistake in each step.
Thanks in advance.
Hi everyone
Fortunately, I managed to finish all steps successfully, however, I couldn’t manage to change parameters in Matlab. For PS I used setparm (‘something’, ‘y’). But here I have no idea. Can anyone tell me how to change these parameters and how o export SBAS results?
setparm(‘something’, ‘y’)
That did not work. when I use the command it successfully works. But when I check the parameters again are set to default.
Thanks for your answer @suribabu. it worked.
Dear @dongyusen @ABraun I have one question, as far as I know, the SBAS is a multi-master method and we choose only one master how is this working? can you explain, please?
If anyone knows please enlighten me.
Hi dear researchers. Thanks for your great work @dongyusen
I managed to finish SBAS_snap2stamps but I think there is something wrong with the results.
The first image is the wrapped phase and the second one is v-dao. As you can see the PSI results are really smooth but the SBAS method, recognized some PS points in the water which causes some problems. I think the problem is with the coregistration part. Can anyone help, please?
SBAS wrapped phase
SBAS v-dao
PSI SBAS
Hi, Dongyusen. I am now applying the SBAS scripts you devloped using Sentinel-1 Descending images. Unfortunately, I am getting this messsage. Please advised me how to correct this probelm. Your help is greatly appreciated.
Mr. alib1
I’m sorry to bother you. I have encountered the same problem during data processing. Would I konw that, what is your solution, or how can I avoid this error?
Mr. damianvz,
I am sorry for borhter you,I have the same Error,Would I konw your solution and how can I avoid ir?
When I run 3sbas_topsar_coreg.py, I get a Error like this. I try to found change "shell=Ture"in “subprocess.py”,however,there is a new error waitting for me.Would I get some advices? @suat @alib1 @dongyusen
Hi @vittoriob
I followed the modified script (ps_load_initial_gamma.m) by @mdelgado and apply it in sb_load_initial_gamma.m.
Basically, the added commands are used to remove NaN and Zero Values that present in LanLot.
you can try edited sb_load_initial_gamma.m
sb_load_initial_gamma.m (6.9 KB)
I hope it helps you.
Regards,
Sudi
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I try to help you @csyoo
In some cases, the output of SNAP contains NaN or Zero Values. You need to remove those NaN and Zero values in STEP 1.
You need add some commands in sb_load_initial_gamma.m to remove NaN and Zero values.
If you don’t mind you can use my edited script here
sb_load_initial_gamma.m (6.9 KB)
It works nice in my SBAS processing.
Best regards,
Sudi
Thank you, Sudi, for your help! I will try.
Thank you Sudi. I’ll try
Hi dear community
I got a question, I’m in STEP 7 trying to check the ifg’s. In the STAMPS User’s manual I found the following paragraph:
As for PS processing, repeating Step 6 after running Step 7 may improve phase-unwrapping accuracy.
Accuracy can also potentially be improved by setting unwrap method to ‘3D’ (default is ‘3D QUICK’
for small baseline processing) before running Step 6, although this will take longer to run.
Unwrapped phase of small baseline interferograms can be viewed using ps plot with the ‘usb’ op-
tions. SCLA error estimated from SB inteferograms can be plotted using the ‘d’ option (the ’D’ option
will give SCLA error estimated from single master interferograms). Residuals between the unwrapped
phase of the small baseline interferograms and that predicted from the model values for the single master
phase can be plotted with the ‘rsb’ option.
The residuals for each small baseline interferogram should be visually inspected, together with the
wrapped and unwrapped phase for each (N.B., you will probably want to view only a few at a time
using the IFG LIST option of ps plot ) . Isolated residuals less than π in magnitude are OK, but
spatially-correlated residuals indicate an unwrapping problem in one or more interferograms. When this is the case, identify which interferogram(s) are incorrectly unwrapped (N.B., one badly unwrapped in-
terferogram can cause non-zero residuals for many interferograms) and drop them from the unwrapping
process, by setting drop ifg index and rerunning Step 6.
You can view a baseline plot for all interferograms not dropped with plot sb baselines .
Does the text in bold mean that I should discard the ifg’s with more than PI in value? or what criteria should I use to discard them?
See below one of the ifg’s I plotted using the rsb option.
