SNAPHU Unwrapping

Hi, if you are using virtual machine to unwrap, you have to increase the ram and disk space. Works for me.

Hi Pancho, I’m not using virtual machine!:confounded :confounded:
I’ve done it for Sentinel!!! but with Palsar I can’t yet.

I’m a Windows user so i’m using Linux in virtual machine to do the snaphu phase unwrapping, and i got the same problem Unexpected or abnormal exit of child process… working with sentinel 1 I just increase the ram and the disk space and it Works. Maybe for Alos palsar could be the same.

Hi all

I did the unwrapped of ALOS PALSAR images, now I will do the calcules to subsidence in an area of interest!

This is the firts result:

Hi Shubham, I’m new in this forum. I read that you resolved the problem, could you explain me what’s the problem with the snaphu data import message “3-SnaphuImport: java.lang.NullPointerException”? I have 2 images S1 and I have used S1 TOPS Coregistration, Interferogram formation, Golstein phase filtering, S-1 TOPS Deburst, Snaphu export, and when I try to import the data into NEST DAT 5.1 appear that message.

I hope that you can help me.

Thanks.

A post was split to a new topic: Acces to InSAR data (Sentinel / Alos)

Hola Jose Luis, yo tambien soy de Colombia y estoy probando con S1 y SNAP, sin embargo tengo problemas para realizar el UNWRAPPING, exporto los datos y trato de seguir el proceso para ejecutarlo en CYGWIN pero no obtengo resultados. Podrias darme una mano con este problema?

I try to arrive to the step “phase to displacement”, therefore I followed S1 TOPS coregistration -> interferogram formation -> S-1 TOPS Deburst -> Topographic phase removal -> Goldstein phase filtering -> SNAPHU export, after, I try to run into cygwin with the following steps: copy the exported files (not folder) to bin folder of SNAPHU-> Open snaphu.conf file -> Run Cygwin as admin -> navigate to bin folder -> Type and execute the command in the conf file, however when I try to execute cywin only appear

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I don’t know if I’m doing something wrong, I hope that you can help me, I only have two weeks to use the computer of the laboratory.

Thanks.

hei gabriel when you import to snaphu (snaphu import), please tell me what you input in 1-read-phase , mine cant work well. thanks

hei all when you import to snaphu (snaphu import), please tell me what you input in 1-read-phase , mine cant work well. thank

Hi Arbad

The input is the image processed before of the export for SNAPHU

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Hi Gabriel

Thankyou for your reply and information, so its mean processed after dinsar and filtering right ? I used ALOS Palsar data but the coherence seem to be like noisy, I cant see anything, have you recommendation ?

Thanks

Hi Arbad

Yes, after dinsar and filtering. Which is the objetive of your study?

Hi gabs,

I will see deformation in volcano area, so I used Snap for processing PALSAR images, and did same way with the tutorial given. but the result is not so good. what do you think about this problem.

regards

Hi again,

Do you have used Sentinel 1 images? I did an displacement map of deformation in Santa catarina Do Fogo volcano, this is the results

I recommend you!!!

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this is interesting. Which dates did you chose?

Hi ABraun

I used images with dates Nov, 03 and Nov, 27 2014.

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alright, thanks - I guess there was an Eruption in between?

Yes, its last eruption was Nov 23 2014.

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Nice work, it sucseeded me to :slight_smile:

Hi,

before unwrapping i need some noise correction…I tried it with band math:

  1. i need to compute the coherence map coh(coh<0.4)=0
    also
  2. to reduce the noise, after goldstein filtering in the PhaseBand:
    coh * Phase_ifg_srd__15Nov2015_23Aug2015

The problem is, this creates two new bands, which will not be processed by the SNAPHU export option of SNAP, so how can I fit this new bands into SNAPHU?

Because obviously I don’t find a way to just edit/make changes on the actual coh and phase bands.