[yaoshuyi]

Hi,

In Multi Image InSAR processing (e.g., APS estimation, Graph refinement and Sparse points processing), where SARproz will read the phase from? I know if I don’t have files in the folder “INTERFEROGRAMS”, SARPROZ will read the phases from “FITTED”, and do Flattening and DEM removal. So what if I have already generated interferograms? If SARPROZ reads phases in “INTERFEROGRAMS”, how can it decide to do Flattening and DEM removal or not (Or how can SARPROZ know if the interferograms are differential interferograms).

I’d like to know these details because I’ve developed a unique multi-temporal filter, and I’d like to convert these filtered phases into Star-Graph interferograms and then let SARPROZ use them in subsequent processing.

Thank you.

[yaoshuyi]

I work with wrapped phases.

[periz]

hi

* Sarproz gives explicit messages about the options that are taken. if you read messages carefully, you should be able to understand whether interferograms are read, whether flattening is assumed and so on
* in any case, if you apply a standard processing, the phase is read from images and the flat terrain phase is removed afterward. you can choose whether to remove the DEM or not and whether to estimate a residual height or not
* phase is read from interferograms only if you choose to use the coherence as a weight. in such case, the software assumes that inteferograms are flattened and that the external DEM was removed
* if no interferograms are available, the phase is taken from images, flat terrain and external DEM as subtracted automatically.

+ in your case, if you want the software to read your custom processed phase, star graph, generate star graph interferograms, choose to weight data with the coherence
+ if you do not want to use a weight in the processing, just set the coherence equal to 1 (it’s the amplitude of interferograms)
+ about naming policies, check here: https://sarproz.com/manual/save_interfs.html

best

[yaoshuyi]

Thank you for your help.

I have another question. Does “weight data with the coherence” make sense if for the same point its coherence is the same on all interferograms, but the coherence may be different between different points?

best

[periz]

it surely makes sense to consider the temporal coherence of a point
but not for estimating height and/or velocity
the temporal coherence is used e.g. to weight the spatial integration of the APS graph
best

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