Problem with Java Null Value when generating DEM data (Interfarometry)

Greetings!

I’ve been trying to use the Sentinel-1 toolbox to process SAR data in an area of the Brazilian Pantanal.
I’m new in SAR technology, but I figured that SAR images would be really useful in my research area because it is not influenced by cloud coverage as it is in the hyperspectral bands I’m used to work. I will use the data collect in different dates to retrieve soil moisture information and high resolution DEM by using interferometry.
Well, I’ve tried a series of methods to generate the interfarograms and to create the DEM and it keep returning the same error.
Java.lang NullpointerExeption. As far as I’m concerned, this error is common and associated with the absence of some information on the objected I’m calling. The error was found when using the customized Graph: Dem-Generation-Pre-Processing. These are the scenes I’m using: ‘S1A_IW_GRDH_1SDV_20150612T091850_20150612T091915_006338_008565_6949’
‘S1A_IW_GRDH_1SDV_20150823T091853_20150823T091918_007388_00A294_72A9’
I would like to now if I’m doing something wrong? Is it the error caused by some missing data on the original product or by the SNAP Sentinel-1 toolbar?
It’s really important for me to process this data.

Thank you in advance!

Thanks, I’ll look into it.

This error I got when trying to apply the Orbit!
java.io.IOException: No memory left for cache!
at javax.imageio.stream.MemoryCache.loadFromStream(Unknown Source)
at javax.imageio.stream.MemoryCacheImageInputStream.read(Unknown Source)
at javax.imageio.stream.ImageInputStreamImpl.readShort(Unknown Source)
at javax.imageio.stream.ImageInputStreamImpl.readUnsignedShort(Unknown Source)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFIFD.initialize(TIFFIFD.java:237)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageMetadata.initializeFromStream(TIFFImageMetadata.java:147)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.readMetadata(TIFFImageReader.java:664)
Caused: javax.imageio.IIOException: I/O error reading image metadata!
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.readMetadata(TIFFImageReader.java:670)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.seekToImage(TIFFImageReader.java:618)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.seekToImage(TIFFImageReader.java:576)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.prepareRead(TIFFImageReader.java:1327)
at it.geosolutions.imageioimpl.plugins.tiff.TIFFImageReader.readAsRenderedImage(TIFFImageReader.java:1374)
at org.esa.s1tbx.io.imageio.ImageIOFile.getData(ImageIOFile.java:304)
at org.esa.s1tbx.io.imageio.ImageIOFile.readImageIORasterBand(ImageIOFile.java:257)
at org.esa.s1tbx.io.sentinel1.Sentinel1ProductReader.readBandRasterDataImpl(Sentinel1ProductReader.java:132)
at org.esa.snap.framework.dataio.AbstractProductReader.readBandRasterData(AbstractProductReader.java:250)
at org.esa.snap.jai.BandOpImage.computeProductData(BandOpImage.java:56)
at org.esa.snap.jai.RasterDataNodeOpImage.computeRect(RasterDataNodeOpImage.java:127)
Caused: java.lang.RuntimeException
at org.esa.snap.jai.RasterDataNodeOpImage.computeRect(RasterDataNodeOpImage.java:129)
at javax.media.jai.SourcelessOpImage.computeTile(SourcelessOpImage.java:137)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:904)
Caused: org.esa.snap.framework.gpf.OperatorException: javax.imageio.IIOException: I/O error reading image metadata!
at org.esa.snap.framework.gpf.internal.OperatorExecutor$GPFImagingListener.errorOccurred(OperatorExecutor.java:375)
at com.sun.media.jai.util.SunTileScheduler.sendExceptionToListener(SunTileScheduler.java:1646)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:921)
at javax.media.jai.OpImage.getTile(OpImage.java:1129)
at javax.media.jai.PlanarImage.cobbleInt(PlanarImage.java:3153)
at javax.media.jai.PlanarImage.getData(PlanarImage.java:2178)
at com.bc.ceres.glevel.MultiLevelImage.getData(MultiLevelImage.java:64)
at org.esa.snap.framework.gpf.internal.OperatorContext.getSourceTile(OperatorContext.java:421)
at org.esa.snap.framework.gpf.internal.OperatorContext.getSourceTile(OperatorContext.java:407)
at org.esa.snap.framework.gpf.internal.OperatorImage.computeRect(OperatorImage.java:73)
at javax.media.jai.SourcelessOpImage.computeTile(SourcelessOpImage.java:137)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:904)
at javax.media.jai.OpImage.getTile(OpImage.java:1129)
at com.sun.media.jai.util.RequestJob.compute(SunTileScheduler.java:247)
[catch] at com.sun.media.jai.util.WorkerThread.run(SunTileScheduler.java:468)

Hope it helps on identifying the problem. Thanks!

The problem above I’ve solved by reinstalling the SNAP 5.0. The error with the DEM generation problem is still the same (DEM-Generation Graph). Besides, the system can not retrieve orbit file to the following scene: ‘S1A_IW_GRDH_1SDV_20150823T091853_20150823T091918_007388_00A294_72A9’
I tried to download it manually and put on the right directory but it does’t help…
I tried with older scenes from Europe (Valid Orbit Files) but the Java Null error is always the same. It does’t matter what I do.

Hi, I have the same problem as you described while try to retrieve DEM, did you find any solution? I sincerely appreciate any help.

Hi,
I want to creat DEM,too.Can you tell me how to do this?Thanks.

Hi

Did you succeed in retrieving soil moisture from sentinel-1? I am also working on this issue and would appreciate any help