[Paraview] HDL import problem

[sm399 at cam.ac.uk]

Dear Paraview users,

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