SNAPHU Unwrapping

there is a tutorial on how you can use the profile plot tool: https://www.youtube.com/watch?v=_g0F-hq3xTs

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hi, did you use sarmint? i want to do the unwrapping process using virtual machine and not the snaphu plugin on snap, but i cant find sarmint .do you know where can i download it?

Hello, I have the same process as you. After step 4, I got the following file.
image|690x182
Now,However, which file should I open in step 5? None of these files seem to open.


Please help me, thank you very much.

@SUN-Ravenclaw: The files we see are the ones which are exported by SNAP. Now you have to run snaphu to create UnwPhase_ifg_[…].snaphu**.img**

After this file was created by snaphu, you an run the import and select this hdr file.

Yes, sir. Is this the option in the red circle below

yes, but it has to be properly installed and executed (explained by @oana_hogoiu here: Snaphu Unwrapping Plugin)

Yes, sir, I have successfully installed the tool. But when I open the “UnwPhase *. hdr” file, it gives the following error message

.
Another thing,I got the "snaphu export"files according to the following figure1/2/3



Is there anything wrong?

for the unwrapping, you have to select the Phase_ifg_VV (the UnwPhase does not exist yet).

The pre-processing of the exported interferogram looks alright, also the file structure from your screenshot above.

Yes, you are right. I should enter Phase_ifg_VV file. In fact, what I input yesterday is also this file, only the output folder and the source product folder are the same. As a result, there is no change in the contents of the folder. Is this a software bug?

It should work actually. Alternatively, you can run snaphu from the command line as described here: Snaphu Export

I am currently preparing a revision of the TOPS InSAR tutorial, but this will still take a bit of time until it is finished.

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That’s great, I look forward to your completion soon.

You can download the tutorial now from here: http://step.esa.int/docs/tutorials/S1TBX%20TOPSAR%20Interferometry%20with%20Sentinel-1%20Tutorial_v2.pdf

The other InSAR tutorials will also be revised in the next weeks: http://step.esa.int/main/doc/tutorials/

I saw in the tutorial how to improve the extracted displacement results. Thank you again, Abraun, you are a very patient and serious person.

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Hi ABraun,

When I tried to use snaphu unwrapping, I am getting following error:

“Unexpected or abnormal exit of child process
Abort”

Attached a screenshot. Can you please tell me what might be a problem and how to solve it?

Thank you!

I’m not sure - please try to increase the number of tiles in the config file and run again.

Hi!

When I increase the number of tiles, I get error saying

“Tiles too small or overlap too large”.

Any suggestions?

Reduce the tile overlap to 50, it depends on the extents of the entire scene.

I am using number of rows and columns as 50. Tile overlap is now set to 100 (It wasn’t working when I had set the overlap to 50). Anyway, I believe I have figured out what was the problem. I will let you know the results.

50 rows and columns is too much, each individual tile should be considerably larger than the defined overlap:

the overlap must be selected in relation to the size of a single tile (can be calculated based on the total image size and the numbers of colums and rows):

If the overlap is the same size as a tile (or larger), snaphu will give this error message.

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