"error in opening zip file" with DEM files

Microwave Toolbox
1

Starting at about 1300 EST on Friday, June 23, I started encountering an error in opening zip file during the terrain correction step. I have tried both SRTM 1Sec HGT and GETASSE30. Neither of them seem to work. I have also tried dozens of different S1 IW GRD HD products. None of the corresponding DEM file worked.

Here is the last bit that raises the error:

INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
INFO: org.esa.snap.engine_utilities.download.DownloadableContentImpl: http retrieving http://step.esa.int/auxdata/dem/egm96/ww15mgh_b.zip
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip
error in opening zip file
100% done.
SEVERE: org.esa.snap.core.dataop.dem.ElevationFile: error in opening zip file
org.esa.snap.core.gpf.OperatorException: error in opening zip file
	at org.esa.snap.core.gpf.internal.OperatorExecutor$GPFImagingListener.errorOccurred(OperatorExecutor.java:381)
	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 com.sun.media.jai.util.RequestJob.compute(SunTileScheduler.java:247)
	at com.sun.media.jai.util.WorkerThread.run(SunTileScheduler.java:468)
Caused by: org.esa.snap.core.gpf.OperatorException: error in opening zip file
	at org.esa.snap.engine_utilities.gpf.OperatorUtils.catchOperatorException(OperatorUtils.java:434)
	at org.esa.s1tbx.sar.gpf.geometric.RangeDopplerGeocodingOp.computeTileStack(RangeDopplerGeocodingOp.java:1104)
	at org.esa.snap.core.gpf.internal.OperatorImageTileStack.computeRect(OperatorImageTileStack.java:122)
	at org.esa.snap.core.gpf.internal.OperatorImageTileStack.computeTile(OperatorImageTileStack.java:86)
	at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:904)
	... 3 more
Caused by: java.util.zip.ZipException: error in opening zip file
	at java.util.zip.ZipFile.open(Native Method)
	at java.util.zip.ZipFile.<init>(ZipFile.java:230)
	at java.util.zip.ZipFile.<init>(ZipFile.java:160)
	at java.util.zip.ZipFile.<init>(ZipFile.java:174)
	at org.esa.snap.dem.dataio.EarthGravitationalModel96.<init>(EarthGravitationalModel96.java:104)
	at org.esa.snap.dem.dataio.EarthGravitationalModel96.create(EarthGravitationalModel96.java:85)
	at org.esa.snap.dem.dataio.EarthGravitationalModel96.instance(EarthGravitationalModel96.java:77)
	at org.esa.snap.dem.dataio.DEMFactory.getLocalDEM(DEMFactory.java:185)
	at org.esa.s1tbx.sar.gpf.geometric.RangeDopplerGeocodingOp.computeTileStack(RangeDopplerGeocodingOp.java:887)
	... 6 more
INFO: org.esa.snap.core.dataop.dem.ElevationFile: http retrieving http://step.esa.int/auxdata/dem/GETASSE30/15S000E.zip

Error: error in opening zip file

Is anyone else also encountering the issue or does anyone know how to get around this?

1 Like
2

Hi @tim ,
I am having the same issue.
Looking at my processing it seems to be started on 23-06-2023 after 12 pm (BST).
Any tips from the forum (@mengdahl @ABraun @jun_lu @lveci )???

S Savastano

4

Hi Tim,

Thank you for your message. There are at the moment some problems with the server, and we are already working on it.
We do our best to fix the problem soon.

5

Hello,
The problem has been fixed. Could you please take a moment to let us know if you are still experiencing any further issues?

Thank you!

6

Hi @diana_harosa
it is working again now.
Thank you very much for your help on this.

Best,
S Savastano

7

Hi @diana_harosa. I can confirm this is working again. Our production workflow starting throwing errors on Friday 23rd June PM with the same error.

In case anyone comes across this in the future, I followed a workaround (see link below) and put a copy of the DEM in this local path $HOME/.snap/auxdata/dem/egm96/ww15mgh_b.zip. This bypassed the need to download the DEM that had the (temporary) bad url.

Thanks for fixing this though!

(I can’t seem to put urls in this post so here’s the link github DOT COM SLASH johntruckenbrodt SLASH pyroSAR SLASH issues SLASH 98#issuecomment-556008274)

8

I can also confirm that it is no longer an issue.

Just curious: was this an issue with the different DEMs or was it as @eo-user pointed out, just the egm96/ww15mgh_b.zip file?

Thank you!
Tim

9

Thank you very much for your help on this.