An inquiry. related Snaphu

Please help me, even if you find my question simple or easy. Your answers will make a big difference to me.I am trying to obtain displacement values for a water structure on the Nile River using open source Sentinel-1 images and SNAP software. I know from previous consultations that to achieve good results, I must follow PSI method. However, as an experiment, I analyzed two images taken eight years apart, and the result was as shown below. I followed a NASA video about the Subsidence of New Mexico, but in the specific step image (1) , when I opened the file of Snaphu, I found only four files out of six. So, I proceeded with the step without adding ( Snaphu, export ) and then performed another action through the top menu to apply Snaphu export using the result image of NASA video , and indeed, I got six files, but i notice that the image of NASA video without the SNAPHU export step was missing the band of (topophase) (image 2)…

The second question for image (3) is, how can I make my structure appear clearly in the result and mark points on it as I have seen in previous studies? Thank you."

image 1


Hi!

No question is too simple. With the Snaphu part, I think that the export hiccup might be due to a skipped step. Double-checking against the SNAP user guide could clear up any differences from the NASA tutorial.

For your second question, have you played around with contrast adjustments or looked into other visualization techniques within SNAP? Sometimes, tweaking these settings can make all the difference. And for pinpointing locations, adding your points in a GIS platform after processing should do the trick.

You can start with SBAS analysis for a broad view and then use PSI for higher spatial accuracy on specific targets like buildings. For live, interactive examples, check out the Google Colab projects on PyGMTSAR’s GitHub: GitHub - mobigroup/gmtsar: PyGMTSAR PyGMTSAR InSAR is powerful and user-friendly InSAR, offering both SBAS and PSI analyses.