As part of my Masters Project I have to create an interferogram using SLC SAR data from sentinel 1. I am following this workflow but as the data is quite large I need to subset it as the computer im working off only has 4GB of RAM. At what stage of the process is it ok to subset the file to the specific study area. Any help would be greatly appreciated.
as an alternative to the S1 TOPS Coregistration you can proceed as follows:
- S1 TOPS Split (select only the required bursts and VV polarization only), perform for both images individually.
- Apply Orbit file
- Coregistration (Radar > Coregistration > Coregistration)
- Interferogram generation
- TOPS Deburst
- Multi-Looking and Goldstein FIitering (optional)
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Thanks very much for your reply.
Subset can ne made after deburst, so why not subset as soon as you can and then create interferogram? Is it wrong on methodological level to create interferograms from debursted subsets? I ask this because lot of users interested in interferometry (snap2stamps) use deburst and subset after interferogram computation.
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When you use the split operator in the beginning of the process chain, you already have a kind of subsetting.
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Dear Colleagues,
This is recently published by RUS, It is very nice step by step InSAR ,
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Mr Abraun I am trying to do a time series using dinsar and also I have a 6gb ram but the images I am working with are pretty large so the process take a lot of time, so subset can be made after TOPS Deburst? or does subset affects the results of the final product?
In advance, thank you for your answer.
You can safely create a subset of the stack after TOPS Deburst. Just make sure to have it at consistent size, otherwise you will get problems after importing the unwrapped file based on a reference product of different size.
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Hi , Im trying to run interferogram genration through gpt tool using a docker image of snap. can someone help withthis
[5] Processing slave file :20220313_IW1.dim
SNAP STDOUT:b"INFO: org.esa.snap.core.gpf.operators.tooladapter.ToolAdapterIO: Initializing external tool adapters\nINFO: org.esa.s2tbx.dataio.gdal.GDALVersion: GDAL not found on system. Internal GDAL 3.0.0 from distribution will be used. (f1)\nINFO: org.esa.s2tbx.dataio.gdal.GDALVersion: Internal GDAL 3.0.0 set to be used by SNAP.\nINFO: org.esa.snap.core.util.EngineVersionCheckActivator: Please check regularly for new updates for the best SNAP experience.\nINFO: org.esa.s2tbx.dataio.gdal.GDALVersion: Internal GDAL 3.0.0 set to be used by SNAP.\nExecuting processing graph\nINFO: org.hsqldb.persist.Logger: dataFileCache open start\n-- org.jblas ERROR Couldn’t load copied link file: java.lang.UnsatisfiedLinkError: /tmp/jblas8081261759353660307/libjblas.so: libgfortran.so.5: cannot open shared object file: No such file or directory.\n\norg.jblas.NativeBlas.dgemm(CCIIID[DII[DIID[DII)V\n done.\n\nError: [NodeId: Back-Geocoding] org.jblas.NativeBlas.dgemm(CCIIID[DII[DIID[DII)V\n-- org.jblas INFO Deleting /tmp/jblas8081261759353660307/libjblas_arch_flavor.so\n-- org.jblas INFO Deleting /tmp/jblas8081261759353660307/libjblas.so\n-- org.jblas INFO Deleting /tmp/jblas8081261759353660307/libgfortran-4.so\n-- org.jblas INFO Deleting /tmp/jblas8081261759353660307/libquadmath-0.so\n-- org.jblas INFO Deleting /tmp/jblas8081261759353660307\n"
[5] Finished process in 4.460224628448486 seconds.
@ABraun please help if possible
There is an entry in the FAQs regarding this jblas error, please check.
Thanks you sir for your help. Got the answers
can i do Deburst before Interferogram generation
the official recommendation is to do it afterwards, but as long as your interferogram looks alright… Please carefully check for any jumps along the burst boundaries.
ok，thx for your help