Georefrence in snap

Please help us understand:

  • Which ALOS-2 products are you using in terms of imaging mode and processing level?
  • You extracted parameters from the ALOS-2 data outside SNAP? In which software and what kind of output did it create?
  • How did you import both the original ALOS-2 and the extracted parameters into SNAP?
  • Do both products have the same extent and pixel numbers? You can check with this button grafik
  • Does the following window open and what did you select?
  1. I extracted height using RVOG model in PolSARprov software. the format of this product is (bin).
  2. pixel sizes of both products are same.

You can directly geocode your result in PolSAR pro given that the paths linking to SNAP binaries are correctly set. This grants that the data is correctly used.

Menu > Utilities > S1 TBX > Geocode parameter

for ((SAR product file)), what image should i use? master or slave? because I extracted height using master and salve images of ALOS-2.

good question, I would select the xml of the master product.

I dont know which file is xml.file?

the one starting with VOL

I did it and I saw this erorr?what is this?

I don’t have an idea, sorry.
You could try using SRTM as input DEM which is automatically downloaded. This could at least exclude the external DEM as an error source.

Thank you so much, I could do it using SRTM dem but, I should do using laser data dem. because laser dem is more accurate than SRTM. How can i correct this error ?

you can use the laser DEM as “External DEM” source in the terrain correction step. Just make sure that it is projected in WGS84, as described in the documentation.

Please also see here: Using External DEM 10x10m

image image
I resampled to 10 meters and also reference is WGS but, I still see this error.

yes, because the coordinate refernce system is UTM (unit=meters).
You need to reproject it to WGS84 (unit=degrees), EPSG:4326

yes, I have found it but, I dont know which should i select?

Defining it in the properties is the wrong way. You will have to reproject the data using Data Management Tools > Projections and Transformations > Raster > Project Raster

You find WGS84 under Geographic Coordinate Reference Systems > World > WGS84

which polsarpro version you are use?

this works since PolSARpro 4.2

polsarpro 5.0.4 did not have this feature.

there should be a SNAP menu actually and I think it was already present in early releases of version 5


oh . it is polsarpro new version. but in esa website the download link is unavalible ???