zahrasadeghi

  • periz started the topic Sarproz Release 2018.0 in the forum Sarproz Forum 7 years ago

    Dear all,

    in the past months we have been working on many small things and some major changes. It is not time yet to release the major changes, but it is worth to focus on the small improvements, now available in the new Sarproz version.

    * VERY IMPORTANT: we have implemented some changes in the licensing system for Linux. Now you should be able…[Read more]

  • cp02 replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    Thanks for your help and suggestions.
    Best regards

  • asteriospapas replied to the topic how to select a high quality reference point in PS processing in the forum Sarproz Forum 7 years ago

    thank you for your help and always fast response.
    asteris

  • periz replied to the topic how to select a high quality reference point in PS processing in the forum Sarproz Forum 7 years ago

    The reference point is a critical step. If the reference point is noisy, this can limit the precision of the final result. If the ref point is moving or if it is at high/low elevation, it can bias the result. If the ref point is in a remote area, errors can propagate and make the APS estimation worse. The software performs some automatic tests…[Read more]

  • periz replied to the topic how to select a high quality reference point in PS processing in the forum Sarproz Forum 7 years ago

    The reference point is a critical step. If the reference point is noisy, this can limit the precision of the final result. If the ref point is moving or if it is at high/low elevation, it can bias the result. If the ref point is in a remote area, errors can propagate and make the APS estimation worse. The software performs some automatic tests…[Read more]

  • asteriospapas started the topic how to select a high quality reference point in PS processing in the forum Sarproz Forum 7 years ago

    Hello,
    always congrats on the work.
    when looking for a good reference point for ps processing, what should we be looking for. Not only on the theoretical side but also from the software’s point of view and results.
    What should we be expecting from the results of the specific point in the end process
    (after the sparse point processing).

    thank…[Read more]

  • periz replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    1. 20 images is a relatively low number. so, you have to be careful in choosing things properly
    2. using the coherence as a weight means using the spatial coherence to keep coherent data and discard not coherent one. if you use the STAR graph, you should not expect high coherence, because of STAR graph long baselines. it means discarding data. it…[Read more]

  • periz replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    1. 20 images is a relatively low number. so, you have to be careful in choosing things properly
    2. using the coherence as a weight means using the spatial coherence to keep coherent data and discard not coherent one. if you use the STAR graph, you should not expect high coherence, because of STAR graph long baselines. it means discarding data. it…[Read more]

  • periz replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    1. 20 images is a relatively low number. so, you have to be careful in choosing things properly
    2. using the coherence as a weight means using the spatial coherence to keep coherent data and discard not coherent one. if you use the STAR graph, you should not expect high coherence, because of STAR graph long baselines. it means discarding data. it…[Read more]

  • periz replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    1. 20 images is a relatively low number. so, you have to be careful in choosing things properly
    2. using the coherence as a weight means using the spatial coherence to keep coherent data and discard not coherent one. if you use the STAR graph, you should not expect high coherence, because of STAR graph long baselines. it means discarding data. it…[Read more]

  • periz replied to the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    1. 20 images is a relatively low number. so, you have to be careful in choosing things properly
    2. using the coherence as a weight means using the spatial coherence to keep coherent data and discard not coherent one. if you use the STAR graph, you should not expect high coherence, because of STAR graph long baselines. it means discarding data. it…[Read more]

  • cp02 started the topic analysis of APS results in the forum Sarproz Forum 7 years ago

    Dear Prof. Perissin,
    I’d like to ask you for any suggestions and opinions about the analysis to better understand the parameters involved in the processing.

    I used Sarproz to analyse 21 Sentinel 1A images over one year. In the preliminary processing I analysed an area of 8 km (radius) for the coregistration of all images. In the final part I…[Read more]

  • asteriospapas replied to the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    I apologise for the delayed thank you.
    We appreciate the help. The results, with carefully consideration of the above suggestions, were found really close to the expectation we had.
    Thank you again and always congrats on the work being done.

  • periz replied to the topic Undo step in the forum Sarproz Forum 7 years ago

    Hi Jaroslav,
    surely, you can undo/recover lots of things in Sarproz (in fact, almost all operations).
    In particular, you can undo “Residual fringes estimation and removal” by clicking on “reset flat/height constants”.
    best

  • jaroslav started the topic Undo step in the forum Sarproz Forum 7 years ago

    Hello!
    Is it possible to undo some processing steps?
    I am particularly interested to undo “Residual fringes estimation and removal” in case it didn’t gave the expected effect.

    j

  • periz replied to the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    About a. b. and c. just go with a. The other options are still experimental.
    About thresholds, use the suggested ones as starting point. If you are not happy, try to rise the minimum value for being more restrictive.

  • asteriospapas replied to the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    Thank you for the super fast response.
    we are running now the data with what you suggested.

    Regarding the graph analysis and refinement, we have looked at it, but we do not understand the parameters exactly what they exactly they are for. Checking the manual it doesn’t really go in depth:
    (from manual)
    3. press the button “go” in the “clusters…[Read more]

  • periz replied to the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    The result looks reasonable.
    To check if the APS was well estimated, you the final “test” function. If the final coherence is high and evenly distributed, you are done. You can also plot the APS one by one to check for issues.
    To understand if the height estimation range is correct, check the histogram of the connections residual height. You can…[Read more]

  • asteriospapas replied to the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    I also added this image.

  • asteriospapas started the topic understanding aps estimations parameters and results in the forum Sarproz Forum 7 years ago

    Hello,
    firstly we would like to congratulate you for the great work that has been put in the sarproz software.

    We would like to get a better understanding on analyzing the parameters and results of the aps processing. We are running 66 sentinel-1 images, from 2014 to 2018, over an area of nearly 16×16 km using a star graph.
    In the sparse point…[Read more]

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