[GRASS-user] HDL import problem

Dear Users,

the problem I am trying to solve is not directly connected to GRASS (although what I am trying to do is to extract info from a volume and then import it into GRASS), but I was hoping there might be someone in the community that has experience with the same kind of data.

I have been given some GPR geophysics data to visualise and use for vector
extraction in Paraview. The data was put together as parallel transects to
create a 3D volume with EKKO_3D. It was then imported and saved in T3D as a
volume HDF and it is saved with an extension .HDL.

I tried to import it into Paraview directly without success. I have also
been trying to find if there is a way to convert an hdf file into .hd5 but
have been unsuccessful in the endeavor. T3D can also store data as .raw but
even in this case I could not find the right translator to import it into
Paraview.

Could anyone suggest what to do in order to open this dataset in Paraview?

Yours gratefully,

Stefania Merlo

sm399@cam.ac.uk wrote on 07/20/2007 06:58 PM:

Dear Users,

the problem I am trying to solve is not directly connected to GRASS
(although what I am trying to do is to extract info from a volume and
then import it into GRASS), but I was hoping there might be someone in
the community that has experience with the same kind of data.

I have been given some GPR geophysics data to visualise and use for
vector
extraction in Paraview. The data was put together as parallel
transects to
create a 3D volume with EKKO_3D. It was then imported and saved in T3D
as a
volume HDF and it is saved with an extension .HDL.

I tried to import it into Paraview directly without success. I have also
been trying to find if there is a way to convert an hdf file into .hd5
but
have been unsuccessful in the endeavor. T3D can also store data as
.raw but
even in this case I could not find the right translator to import it into
Paraview.

Stefania,

I don't know anything about EKKO_3D, T3D or .HDL but I see that GDAL
appears to partially (?) support HDF volumes:

bartok:gdal[12761.3] grep -i vol frmts/hdf4/*
frmts/hdf4/hdf4imagedataset.cpp: an image at a time to form
a volume.
frmts/hdf4/hdf4imagedataset.cpp: A rank 4 dataset may be
thought of as a series of volumes.
frmts/hdf4/hdf4imagedataset.cpp: case 4: // 4Dim: volume-time
frmts/hdf4/hdf4imagedataset.cpp: case 3: // 3Dim: volume
frmts/hdf4/hdf4imagedataset.cpp: case 4: // 4Dim: volume
frmts/hdf4/hdf4imagedataset.cpp: case 3: // 3Dim: volume
frmts/hdf4/hdf4imagedataset.cpp: case 3: // 3Dim: volume

What does 'gdalinfo' say about this data set? That's probably the
starting point.

ciao
Markus

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ITC -> dall'1 marzo 2007 Fondazione Bruno Kessler
ITC -> since 1 March 2007 Fondazione Bruno Kessler
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