sarproz-group

Combine different geometries for decomposition of LOS motion?

This topic contains 7 replies, has 2 voices, and was last updated by  ceciliabo 1 month ago.

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  • #2390

    ceciliabo
    Participant

    Hello,
    I have two datasets of Sentinel images (one ascending and one descending). I would like to know if it is possible through the software to decompose the LOS motion in vertical and horizontal components.
    Or simply, I have to process the two datasets separetely and then apply some formula using the LOS values? In that case, which formula(s)?

    Thank you
    Cecilia

  • #2391

    periz
    Keymaster

    Ciao Cecilia,
    yes, you can, through this module: http://sarproz.com/manual/multi_sens.html
    Unfortunately the module is a beta version and not all functions are available.
    Anyway, you can align your datasets, select ascending/descending corresponding points, then plot the projections.
    You have firstly to process asce/desce datasets separately, then export time series objects and then import them in such module.
    Vertical/horizontal movements can be plotted either on AD pairs or on resampled grids. In the future we’ll give more options for resampling. At the moment the time series export in not implemented yet but we’ll do it soon.
    Let me know if you get it working or if you need a remote session to show you how to use it
    best

  • #2396

    ceciliabo
    Participant

    Thanks for the super quick answer.
    Yes I get a little bit lost in the export part. So I process the sets separately (and here all clear). About the export..I am working with a small area, so with Small Area Processing. So what I have to do is “just” click export the time series in the geocoding window, and then the software will recognize automatically the objects to import in that module?
    If available, yes it would be very helpful to see a tutorial or something similar.
    Thanks again
    Cecilia

  • #2398

    ceciliabo
    Participant

    Also, what happens if the PS points are not coincident in the two datasets?

  • #2399

    periz
    Keymaster

    A Time series object is a Sarproz internal data structure,
    formed by a file with .tsobj extension and a folder.
    Such structure can be optionally generated either from the APS module, or from the MISP one (APS and MISP are module for estimating time series models).
    Alternatively, there is a module where you can generate a TS object without estimating models, simply by reading information already available (e.g. because previously estimated): http://sarproz.com/manual/ts_module.html
    At the moment you cannot create such TS objects from the small area module.
    Many years ago it was possible to jointly combine multiple datasets using the small area module, but that functionality is currently disabled because obsolete.
    About your second question, the Multi-Sensor module allows finding corresponding points from the 2 datasets, by better aligning the 2 datasets and by placing thresholds on the distance between corresponding points. Once they are aligned, you can also choose to resample your data on a regular grid, in this way you get corresponding areas instead of corresponding points.
    We have several improvements to do on this subject, we’ll work on them in the next months.

  • #2406

    ceciliabo
    Participant

    Thanks very much for the explanation.
    Although, I have not really understood what I should do in practice (sorry, for me is a quite new world…and software).
    I process the two datasets using Site Processing and then..? I use the multi sensor analysis module? Or I need to do something else in the middle?
    Thanks for the infinite patience

  • #2407

    periz
    Keymaster

    the minimum required is estimating the time series using the APS module, then save the corresponding TS object, for both datasets.
    when you have the 2 TS objects, you can import them in the multi-sensor moduel.
    depending on what you are doing, you may want to process also the MISP after the APS.
    here you see some exercises for the APS and MISP modules https://www.sarproz.com/by-timo-balz/
    however, probably you need a training on the subject.

  • #2413

    ceciliabo
    Participant

    Thank you for the further clarification.

    I will try then

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