I am getting a problem using SNAP when I try to aplly the interferometry. This problem occurs while trying to coregistrate the two images. an error appears:
" Error: [Noted: Back-Geocoding] org.jblas.NativeBlas.dgemm…"
I’ve coregistered two S1 images the first time with SRTM 1sec HGT and the second time with SRTM 3sec.
In the first try the “mask out areas with no elevation” didn’t have any effect and the area coincident with the mediterranean sea was not masked out (image A).
In the second case the “mask out areas with no elevation” did have the right effect and the area coincident with the mediterranean sea was masked out (image B).
I have two question. 1. Why with the use of the SRTM 1sec HGT the sea isn’t masked out? Which 1sec DTM allows the masking of the sea? 2. Coregistering with the SRTM 3sec affects the resolution of the two images?
maybe the area is considered shelf or flat shore in the 3Sec SRTM and water in the 1Sec SRTM? If you check the “DEM” option during terrain correction, the underlying SRTM data is also written into the target product. You can then check with the pixel info tool what values are used for this area in 1Sec and 3Sec.
The spatial resolution of the primary image defines the spatial resolution of the output. The SRTM is upsampled for this task.