Hello,
I used the graph processing tool in SNAP to generate a processing flow, which included terrain correction (I am using SNAP v5.0). However, whenever I tried to run my .xml graph, I got the following error:
Error: [NodeId: Terrain-Correction] Operator ‘RangeDopplerGeocodingOp’: Unknown element ‘alignToStandardGrid’
After some digging around, I discovered that commenting out the problematic section, to make the terrain correction node look like:
<node id="Terrain-Correction">
<operator>Terrain-Correction</operator>
<sources>
<sourceProduct refid="Calibration"/>
</sources>
<parameters class="com.bc.ceres.binding.dom.XppDomElement">
<sourceBands/>
<demName>SRTM 3Sec</demName>
<externalDEMFile/>
<externalDEMNoDataValue>0.0</externalDEMNoDataValue>
<externalDEMApplyEGM>true</externalDEMApplyEGM>
<demResamplingMethod>BILINEAR_INTERPOLATION</demResamplingMethod>
<imgResamplingMethod>BILINEAR_INTERPOLATION</imgResamplingMethod>
<pixelSpacingInMeter>10.0</pixelSpacingInMeter>
<pixelSpacingInDegree>8.983152841195215E-5</pixelSpacingInDegree>
<mapProjection>GEOGCS["WGS84(DD)", 
DATUM["WGS84", 
SPHEROID["WGS84", 6378137.0, 298.257223563]], 
PRIMEM["Greenwich", 0.0], 
UNIT["degree", 0.017453292519943295], 
AXIS["Geodetic longitude", EAST], 
AXIS["Geodetic latitude", NORTH]]</mapProjection>
**<! -- <alignToStandardGrid>false</alignToStandardGrid>**
** <standardGridOriginX>0.0</standardGridOriginX>**
** <standardGridOriginY>0.0</standardGridOriginY> -->**
<nodataValueAtSea>false</nodataValueAtSea>
<saveDEM>false</saveDEM>
<saveLatLon>false</saveLatLon>
<saveIncidenceAngleFromEllipsoid>false</saveIncidenceAngleFromEllipsoid>
<saveLocalIncidenceAngle>false</saveLocalIncidenceAngle>
<saveProjectedLocalIncidenceAngle>false</saveProjectedLocalIncidenceAngle>
<saveSelectedSourceBand>true</saveSelectedSourceBand>
<outputComplex>false</outputComplex>
<applyRadiometricNormalization>false</applyRadiometricNormalization>
<saveSigmaNought>false</saveSigmaNought>
<saveGammaNought>false</saveGammaNought>
<saveBetaNought>false</saveBetaNought>
<incidenceAngleForSigma0>Use projected local incidence angle from DEM</incidenceAngleForSigma0>
<incidenceAngleForGamma0>Use projected local incidence angle from DEM</incidenceAngleForGamma0>
<auxFile>Latest Auxiliary File</auxFile>
<externalAuxFile/>
</parameters>
</node>
seemed to work (the commented section is between the ** characters). However, the default value for aligntostandardgrid is “false”, which is what I was using initially, but this still seemed to cause problems. There seems to be a problem with s1tbx\s1tbx-op-sar-processing\src\main\java\org\esa\s1tbx\sar\gpf\geometric\RangeDopplerGeocodingOp.java, and it might be worth investigating this at source level.