Problem in runing mt_prep_gamma_snap

Thank you so much for your help@ABraun

I have rerun stamps(6,6) and stamps(7,7) and setparm('scla_deramp', 'y'). I got results which i have attached below kindly have a look and suggest me these results are fine or any other enhancement or processing is still required?? As i am new on StaMPS working so any further suggestion will be helpful for my study and research.
THank you.
ps_plot(‘w’)


ps_plot(‘u’)

ps_plot(‘u-dm’)

Sorry, but I cannot tell if this is fine by looking at it. To me, these are just colorful dots :wink:

You have to relate it to the conditions in your study area and check if the spatial and temporal patterns.

To me, the most important command to check the overall result is
ps_plot('v-do')

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I have run this command ps_plot(‘v-do’) and i have got some results kindly have a look and suggest me what further should i do?
Thank you.

I can only give technical advice. The analysis is finished, but I can’t tell if the result is within a reasonable range of values, or if the pattern makes sens. This is up to you.

You can export the results as a kmz file and display them in Google Earth, for example, to use it as an overlay on a satellite image.

It is explained in the manual:

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ps_gescatter(‘project_velo.kml’,ph_disp,10,0.4) @ABraun is this command is right because when i run this it again said undefined function, so i want to ask is there is problem with my command or this command vary with selection of threshold value?

the command alone is not enough, the export consists of three commands - please just read the suggested source :slight_smile:

to export the kml (every 10th point):

ps_plot('v-do', -1)
load ps_plot_v-do ph_disp
ps_gescatter('project_velo.kml', ph_disp, 10, 0.4)
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Thank you @ABraun i will run this command.

I have noticed there is atmospheric factor in my results i want to remove that factor from my results. So, should i run stamps(8,8) and later use train software to remove atmosphere factor or directly use train or stamps(8,8) would be enough? from the train manual its quite difficult to understand that what to use from the package and how to use… there are majorly power and linear techniques but i could not understand about it…

the atmospheric correction which is included in step 8 of SNAP is just a temporal low-pass filter - nothing really sophisticated. It does not include actual atmospheric data such as TRAIN or GACOS.

If you want to include it, I suggest this very useful site:

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So stamps(8,8) is not as useful to refine results… here in this site it shows step 9 is TRAIN but is it work directly in MATLAB? or should we install it and use it separately from stamps?

sorry, I have never integrated TRAIN.
The integrated filtering in step 8 is okay, but no replacement for actual atmospheric atrifacts

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Thank you @ABraun for your help… i have run stamps(8,8) , for TRAIN i will go through the forum to know further…

as suggested in the source, it is advisable to test different values for

  • scn_wavelength
  • scn_time_win

and their effect on the result. As it is the last step, it should not take to long to recompute step(8,8) under different configurations and compare the result.

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You mean like this? but should these commands run together at same time or they should run separately? and these comands must run after stamps(8,8) right?
setparm(’scn_wavelength’,120)
setparm(’ scn_time_win’,400)

first you change the parameters (one by line, so separately), then you repeat stamps(8,8) and check if the result is different.

But a temporal window of 400 days makes only sense if your investigated period is at least this long.

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okay i will run separtely,

you mean it depends on time spam of images? valid point which i didn’t even think, if i calculate ,my images lie with in 385 days. Step 8 seems tricky.

a value of 400 would mean that each interferogram is averaged by all other ones, because they all lie inside this time window. Try something shorter to reduce the amount of filtering, but this also means potentially higher atmospheric contributions.

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okay i will set these values carefully. I want to know that is there any computation limit? i mean is there any issue if i rerun stamps(8,8) multiple times? because it will recompute in every rerun.

no, you can repeat step 8 as often as you want, the results will be overwritten.

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