I am trying to create a custom Sentinel-1 ortho-image generation graph, which is supposed to provide a Geotiff in the end to use it externally. Here’s what I do, including the options:
- Read (Data Format: Sentinel-1)
- Apply-Orbit-File (Orbit State Vectors: Sentinel Precise, Polynomial Degree: 3)
- ThermalNoiseRemoval (Polarisations: VV, Remove Thermal Noise)
- Speckle-Filter (Source Bands: Intensity_VV, Filter: Refined Lee)
- Terrain-Correction (Source Bands: Intensity_VV, DEM: SRTM 1Sec HGT, DEM Resampling: BILINEAR, Image Resampling: BILINEAR, Pixel Spacing: 10 m, Map Projection: UTM Zone 32, WGS84, Output bands for: Selected source band, nothing else checked)
- Write (Save as: GeoTIFF)
I tested the graph on a recent Sentinel-1 IW GRD image, and at first it seems to work like a charm. But when I open the final GeoTIFF (about 2.5 GB in size), I don’t get anything: QGIS tells me only about NaNs, GIMP opens an empty, completely transparent image, and SNAP itself shows some JAVA exception error.
I am using SNAP 5.0.8. on a 64bit Ubuntu machine.
Does anybody have any idea what went wrong?