I am mostly confused with the extra dependencies and am unsure whether i should install all or not, thanks for your help, when back to my linux pc I will look into making it work.
With MATLAB, which are the input datas? It means, should it be the .dim file?
to get into the StaMPS matlab processing you need to use the stamps export function from SNAP or use the python wrapper from the snap2stamps package. The function will generate the correct files and folder structure for you to use in StaMPS and later in TRAIN. Have you read the blog i have send you, this should guide you nicely?
Please some body can explain me, how I can obtain the .dat files that I need for the correction in TRAIN?
I should read this from .dim file of my ifg???
Thanks for advance
I am currently doing DInSAR for 2 months already. I haven’t started learning PSI/SBAS using StaMPS (because of my coursework load).
I just want to ask a detailed step-by-step procedure in SNAP on how to do atmospheric correction for one interferogram? If there is any straight forward process in SNAP without using a third-party app (eg TRAIN).
And when is it significant or not significant to consider the effects of the atmosphere?
Thank you, and my apologies.
The steps of one interferogram creation to measure the displacement or DEM production is explained in the following post,
The atmospheric effect should be excluded, subtracted while implementing steps 5 (interferogram formation),
But as details step by step atmospheric correction procedure of one Interferogram, I think it’s not supported by SNAP atm, But I agree with you, it would be very nice in case it could be included.
This only in StaMPS, and TRAIN could be discriminated,
Yes. I think it would be nice and convenient if atmospheric correction can be done directly through SNAP.
I’ve done a number of DInSAR analyses for 1 location in Korea considering ascending orbit (21 pairs) and descending orbit (22 pairs) and plotted displacement (LOS) over time. All estimations were generally uprising. My supervisor finds it strange because he thinks it should subsidence due to the possibility of groundwater drawdown during the tunneling activity.
I’ve also noticed that the selection of the reference point is very important for the generation of final displacement (LOS) map. With an initial reference point of my choice (eg along a road), I got subsidence. But when I changed it to another one (eg coincident with a building), I got uprising. I know that the choice of the reference point is also affected by the degree of coherence. For my reference point on a building, I am sure that all coherence values over time were closed to 1.0 (>0.95). For the point along the road, I didn’t record these values.
Now, it got into me that maybe the errors could be caused by the effect of the atmosphere.
Anyway, my apologies for sharing a long story here.
I think I will consider TRAIN for my DInSAR analysis to eliminate the atmospheric effects.
No need to apologize, because this is the goal beyond this great STEP FORUM, we meet and discuss from different part of universal to interchange our expertises,
Hope you could share the technical steps and the result after implementing TRAIN,
Hopefully, because I am always the one being helped.
Also, I got this one answer about atmospheric effects in the interferogram phase. This is from HAZA03.
“An indirect way to identify potential contribution of the atmosphere is to generate multiple inteferograms over the same period using different DInSAR pairs and compare the obtained displacement estimates.”
Below is the screenshot of my interferogram products. Is this what it means by multiple interferograms?
Yes, this could be great idea as well,
No, I meant the result of TRAIN results of some interferogram like before and after, to compare the A. effects, And how did you use TRAIN,
I did my request for google group of TRAIN, meanwhile also, I did the request for the GACOS atmospheric correction platform, they answered me and send me maps (.ztd files) of each images with their date … but, now I don ’ t know, how I can use this maps to make my ifgs again ???
Somebody have an idea?
Thanks for advance
Hi，GACOS provides the matlab code, you just provide the unwraphase file
Thanks @hexishan, which format is for the ifg? .dim?
Somebody ti know where is the value of zenith total delay in the metadata of Sentinel 1? or how I can calculate this?
No,I use the geocoeded unwraphase file,which format is .tif, I used matlab to read and convert to binary format! * I can make the program work, but I’m not sure it’s correct fig|666x500
geocoded unwrapped ??? really???
In the forum https://groups.google.com/forum/#!searchin/train_support/tutorial|sort:date/train_support/y5Yldmey1xw/Q7c5_va2skAJ David Bakaert mentions that he made a tutorial that includes the data to test TRAIN, but I can’t find it on his page, I can’t ask be cause my application is pending to approval.
Can anyone share this tutorial?
Please take a look it is here,
Thank you @falahfakhri .
I tried to access the download link but it apparently doesn’t work. I will send an email to David to ask him directly for the tutorial.
While trying to run TRAIN with a data set processed with STAMPS, I got the following results:
I’m really not sure of the result or if I apply TRAIN well.
No it works, but simply doesn’t show any download action, you could find it within the folder where you download your data, TRAIN_manual.pdf (673.4 KB) But I uploaded it to you in any case,
You could see what you have removed using the command ps_plot(‘o’,1) .
Could you check up this as well ! ps_plot(‘u-dmo’,1)
Could you share the results before applying TRAIN!