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


#830

is it an option to process it without multiple patches?

mt_prep_snap date folder 0.4 1 1 50 200


#831

Normally that happens if an interferogram is empty or any slave full zeros.

had you checked that? or could you check that?


#832

Sorry for my question, how I can check this???

I checked my mean amplitude and I filtered the images in function of this results


#833

the “number of pixels with zero amplitude” is extremely high throughout all interferograms. Did you have a look at one of the interferograms in SNAP? Maybe they have a nodata strip at one side, for example. I think this is what mdelgado means.
Edit: Like here, for example.


#834

You can open the interferograms on SNAP and visualize them.

On next version of snap2stamps, I will provide scripts to create png out of the interferograms, so you could check it out easier. For the moment my suggestion is to open them in SNAP.


#835

@ABraun in my last processing of June 2018 (with other data set) where I obtained good results, too had high values Number of pixels with zero amplitude= XXX!!!
I am still checking the ifgs according to all your suggestions!!!
:cold_sweat::cold_sweat::cold_sweat:


#836

I solved the zero size files problem by changing samples.
Now Stamos(1,1) shows error:

Unable to read file ‘…/day.1.in’: no such file or directory.

I could not find a file with this name. What’s this? How can I make it?


#837

First of all @rostamiani,

The issues you are facing/reporting are all due to be using all versions of StaMPS. Please get the latest developer version where the main problems are already solved.

Regarding the day.1.in is a file containing the slave folder names (for example 20170612, … ).
Along that file you would probably need the heading.1.in or master_day.1.in which file name reflects the expected content.

I hope this helps


#838

Thanks

I’m using the latest version (StaMPS 4.1-beta). But could not find anything about these files in the documentation.
How can I create them? Is there any documentation?


#839

These files should be created (if all pre-processing was succesful and you use proper tools to do so) using the scripts included in the package( i.e. when you use mt_prep_snap)

If you need I can share with you some file examples of previous processings.

I hope this helps


#840

Hello @m477h145 and others.

In my study i also found 0 Ps pixels.

“PS_SELECT: 0 ps selected after re-estimation of coherence”

As a result of 0 PS pixel, steps not completed. Did you find any solution about this problem?

Thank you.


#841

Hi @volkan ,

you might want to check if there are any empty files among your radar data and interferograms. This is not checked within StaMPS, so no warning is raised if one or more of your interferograms are somehow messed up . However, you should get a warning when calling mt_prep_snap (something related to related to having 0 mean amplitude, see posts #461ff above). Make sure to remove all files referring to the specified date (both in the rslc and diff0 directories).

Apart from that, there’s the obvious hint to slightly increase your amplitude dispersion index.


#842

I looked the lines after mt_prep_gamma_snap command and there is no zero amplitude pixel. So, can we say the problem is not about 0 mean aplitude?

Amplitude Dispersion Threshold: 0.4
Processing 1 patch(es) in range and 1 in azimuth
 
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141015.rslc...
Mean amplitude = 58.0443
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141108.rslc...
Mean amplitude = 56.7398
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141214.rslc...
Mean amplitude = 55.3928
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150119.rslc...
Mean amplitude = 50.2859
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150224.rslc...
Mean amplitude = 54.4745
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150308.rslc...
Mean amplitude = 52.1636
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150413.rslc...
Mean amplitude = 61.8206
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150507.rslc...
Mean amplitude = 60.4407
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150624.rslc...
Mean amplitude = 67.7829
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150706.rslc...
Mean amplitude = 64.6618
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150823.rslc...
Mean amplitude = 66.5205
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150916.rslc...
Mean amplitude = 62.4759
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151010.rslc...
Mean amplitude = 69.5845
Number of pixels with zero amplitude = 4
Number of pixels with amplitude different than zero = 20331
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151103.rslc...
Mean amplitude = 61.2597
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151209.rslc...
Mean amplitude = 52.6889
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160219.rslc...
Mean amplitude = 55.5107
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160314.rslc...
Mean amplitude = 57.6025
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160501.rslc...
Mean amplitude = 56.7956
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160525.rslc...
Mean amplitude = 56.5111
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160630.rslc...
Mean amplitude = 58.5274
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160805.rslc...
Mean amplitude = 62.3036
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160829.rslc...
Mean amplitude = 57.3653
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160910.rslc...
Mean amplitude = 58.875
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20161028.rslc...
Mean amplitude = 55.6083
Number of pixels with zero amplitude = 0
Number of pixels with amplitude different than zero = 20335
245
83
mt_extract_cands Andy Hooper, Jan 2007
 
Patch: PATCH_1
file name for zero amplitude PS: pscands.1.ij0
dispersion threshold = 0.4
width = 245
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141015.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141108.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20141214.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150119.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150224.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150308.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150413.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150507.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150624.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150706.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150823.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20150916.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151010.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151103.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20151209.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160219.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160314.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160501.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160525.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160630.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160805.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160829.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20160910.rslc...
opening /home/volkan/Desktop/PSI/INSAR_20151010//rslc/20161028.rslc...
number of amplitude files = 24
number of lines per file = 83
patch lines = 83
patch width = 245
opening /home/volkan/Desktop/PSI/INSAR_20151010/...
opening pscands.1.ij...
width = 245
opening /home/volkan/Desktop/PSI/INSAR_20151010//geo/20151010.lon...
opening /home/volkan/Desktop/PSI/INSAR_20151010//geo/20151010.lat...
opening pscands.1.ij...
width = 245
opening /home/volkan/Desktop/PSI/INSAR_20151010//geo/elevation_dem.rdc...
opening pscands.1.ij...
width = 245
number of interferograms = 23
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20141015.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20141108.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20141214.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150119.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150224.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150308.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150413.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150507.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150624.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150706.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150823.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20150916.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20151103.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20151209.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160219.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160314.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160501.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160525.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160630.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160805.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160829.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20160910.diff...
opening /home/volkan/Desktop/PSI/INSAR_20151010//diff0/20151010_20161028.diff...
1 of 23 interferograms processed
2 of 23 interferograms processed
3 of 23 interferograms processed
4 of 23 interferograms processed
5 of 23 interferograms processed
6 of 23 interferograms processed
7 of 23 interferograms processed
8 of 23 interferograms processed
9 of 23 interferograms processed
10 of 23 interferograms processed
11 of 23 interferograms processed
12 of 23 interferograms processed
13 of 23 interferograms processed
14 of 23 interferograms processed
15 of 23 interferograms processed
16 of 23 interferograms processed
17 of 23 interferograms processed
18 of 23 interferograms processed
19 of 23 interferograms processed
20 of 23 interferograms processed
21 of 23 interferograms processed
22 of 23 interferograms processed
23 of 23 interferograms processed

#843

What is left is to check the interferograms, unfortunately there you have 2 options:

  1. visual inspection opening them into SNAP
  2. create a script to do png of your interferograms

Let us know.


#844

I used snap6.0 to prepare stamps.My chain:read,split,apply orbit,backgeocoding,deburst,and interforgram formation,stamps out.But i got an unexpected result after interforgram.the intensity image were almost black.i did’n know where is wrong .wish reply@FeiLiu@ABraun@ katherine


#845

the dark intensity image is fine. I asked the same question here and mengdahl gave an answer: TopoPhaseRemoval and stack


#846

thankyou for hlep me.but now i met another issue is that backgeocoding six splited-orbited dim file,why only the master one is ok,other slave i ,q,intensity image are all empty.wish help @ABraun@lveci. Much appreciate


S1 back geocoding dosen't work
#847

Yeah. This problem happening everywhere.


#848

how did you solve it?can share it.much thaks.


S-1 TOPS Coregistration error
#850

I re-applied SNAP steps (split/orbit/back geocoding/deburst/subset/interferogram formation/export) with new images. And still i find 0 PS pixel (“PS_SELECT: 0 ps selected after re-estimation of coherence”) when i run stamps ( version 3.3b1 under Ubuntu)

I shared SNAP export screenshots and the original files with link below.

Stamps export files

Is there any problem until this stage? Thank you.