GPT - Missing/Wrong Projection GEOTIFF

Microwave Toolbox
1

Hi all,

I am running SNAP 6.0 (S1TBX version 6.0.4) and I have a problem on the projection of geotiffs using the GPT. I am running a graph in SNAP on Sentinel-1 IW imagery and write the result als geotiff. All is fine and geotiff has the correct projection which I can see in ENVI/IDL.

If I am running the same graph in the GPT, saving the output as geotiff, the projection is wrong/missing.

I tested with a standard graph (Read --> Apply-Orbit-File --> TOPSAR-Split --> TOPSAR Deburst --> Terrain Correction).

Is this a bug in GPT of SNAP 6.0? I have not observed this problem in GPT SNAP 5.x - as far as I remember corretcly.

Thanks for your help,
Tobias

The correct geotiff tags should be:
** Structure <2bc01ec0>, 6 tags, length=176, data length=166, refs=1:
MODELTRANSFORMATIONTAG
DOUBLE Array[4, 4]
GTMODELTYPEGEOKEY
INT 1
GTRASTERTYPEGEOKEY
INT 1
GTCITATIONGEOKEY
STRING ‘WGS 84 / UTM zone 32N’
PROJECTEDCSTYPEGEOKEY
INT 32632
PCSCITATIONGEOKEY
STRING ‘WGS 84 / UTM zone 32N’

But what I observe after processing with GPT is:
** Structure <2b3b3510>, 7 tags, length=48, data length=40, refs=1:
GTMODELTYPEGEOKEY
INT 2
GTRASTERTYPEGEOKEY
INT 1
GEOGRAPHICTYPEGEOKEY
INT 6326
GEOGCITATIONGEOKEY
STRING ‘World Geodetic System 1984’
GEOGANGULARUNITSGEOKEY
INT 9102
GEOGSEMIMAJORAXISGEOKEY
DOUBLE 6378137.0
GEOGINVFLATTENINGGEOKEY
DOUBLE 298.25722

2

Problem solved.

In the GPT it says:
-t The target file. Default value is ‘target.dim’.
-f Output file format, e.g. ‘GeoTIFF’, ‘HDF5’, ‘BEAM-DIMAP’. If not specified, format will be derived from the target filename extension, if any, otherwise the default format is ‘BEAM-DIMAP’. Ony used, if the graph in does not specify its own ‘Write’ operator.

However, " -f ‘GeoTIFF’ " must be specified to process correct geoinformation, even if the finlename extension is “*.tif”.

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