[Paraview] VTK XML binary file format

Thierry Dubuis tdubuis at scconsultants.com
Wed Jan 11 12:38:08 EST 2006


Hello Peter,

Sorry, I don't read the binary Base64 encode directly, but after debug 
Paraview
I saw the twelve firsts offsets [0-11] are read Ok but the following 
offsets (12,13,14,15) have the value -842203084

You must have a problem in your write function.

I hope this informations could help you to find your problem.

Best regards,
Thierry Dubuis

Peter Bastian wrote:

>Hi all,
>
>I am trying to write VTK XML unstructured grid files (.vtu) by myself
>(i.e. without using vtkXMLUnstructuredGridWriter). Ascii works fine but
>binary makes problems. I followed the instructions given previously on
>this list, i.e. I use inline DataArrays, put the size of the data in
>front of the block and encode everything base64.
>
>Now there are two problems:
>
>1) The "offsets" array causes an error when reading:
>
>peter at cray:~/FE/dune-dd$ paraview
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/amy/ParaViewReleaseRoot/paraview-2.4.1/VTK/IO/vtkXMLUnstructuredDataReader.cxx
>(592)
> vtkXMLUnstructuredGridReader (0x8dfacb0): Cannot read cell connectivity
>from Cells in piece 0 because the "offsets" array is not monotonically
>increasing or starts with a value less than 1.
>ErrorMessage end
>
>When I write only the offsets array in ascii, the file is read without
>error message. This is curious because all the writing is done by one
>class in my code. I also checked the encoded binary data and it looks OK.
>
>2) Loading the file with all in binary except the "offsets" array, the
>point data as well as the cell data and the point positions are not correct.
>
>Now my question:
>
>Is there some further undocumented magic (like the size in bytes at the
>beginning) that I have to consider?
>
>I would prefer to write VTK files without linking in VTK itself.
>In the attachment I append binary and ascii versions of my file.
>
>Thanks for any response.
>
>-- Peter
>------------------------------------------------------------------
>Peter Bastian, IWR,Uni Heidelberg, INF 348,R 020, 69120 Heidelberg
>email: Peter.Bastian at iwr.uni-heidelberg.de   Tel: +49 6221 54 4984
>WWW: http://www.iwr.uni-heidelberg.de/~Peter.Bastian Fax: ... 8860
>
>  
>
>------------------------------------------------------------------------
>
><?xml version="1.0"?>
><VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian">
>  <UnstructuredGrid>
>    <Piece NumberOfPoints="25" NumberOfCells="16">
>      <PointData Scalars="exact">
><DataArray type="Float32" Name="exact" format="ascii">
>0 0 0 0.0625 0 0.125 0 0.1875 0 0.25 0 0.125 
>0.25 0.375 0.5 0 0.1875 0.375 0.5625 0.75 0 0.25 0.5 0.75 
>1 
></DataArray>
>      </PointData>
>      <CellData Scalars="exact">
><DataArray type="Float32" Name="exact" format="ascii">
>0.015625 0.046875 0.078125 0.109375 0.046875 0.140625 0.234375 0.328125 0.078125 0.234375 0.390625 0.546875 
>0.109375 0.328125 0.546875 0.765625 
></DataArray>
>      </CellData>
>      <Points>
><DataArray type="Float32" Name="Coordinates" NumberOfComponents="3" format="ascii">
>0 0 0 0.25 0 0 0 0.25 0 0.25 0.25 0 
>0.5 0 0 0.5 0.25 0 0.75 0 0 0.75 0.25 0 
>1 0 0 1 0.25 0 0 0.5 0 0.25 0.5 0 
>0.5 0.5 0 0.75 0.5 0 1 0.5 0 0 0.75 0 
>0.25 0.75 0 0.5 0.75 0 0.75 0.75 0 1 0.75 0 
>0 1 0 0.25 1 0 0.5 1 0 0.75 1 0 
>1 1 0 
></DataArray>
>      </Points>
>      <Cells>
><DataArray type="Int32" Name="connectivity" format="ascii">
>0 1 3 2 1 4 5 3 4 6 7 5 
>6 8 9 7 2 3 11 10 3 5 12 11 
>5 7 13 12 7 9 14 13 10 11 16 15 
>11 12 17 16 12 13 18 17 13 14 19 18 
>15 16 21 20 16 17 22 21 17 18 23 22 
>18 19 24 23 
></DataArray>
><DataArray type="Int32" Name="offsets" format="ascii">
>4 8 12 16 20 24 28 32 36 40 44 48 
>52 56 60 64 
></DataArray>
><DataArray type="UInt8" Name="types" format="ascii">
>9 9 9 9 9 9 9 9 9 9 9 9 
>9 9 9 9 
></DataArray>
>      </Cells>
>    </Piece>
>  </UnstructuredGrid>
></VTKFile>
>  
>
>------------------------------------------------------------------------
>
><?xml version="1.0"?>
><VTKFile type="UnstructuredGrid" version="0.1" byte_order="LittleEndian">
>  <UnstructuredGrid>
>    <Piece NumberOfPoints="25" NumberOfCells="16">
>      <PointData Scalars="exact">
><DataArray type="Float32" Name="exact" format="binary">
>ZAAAAAAAAAAAAAAAAAAAAAAAgD0AAAAAAAAAPgAAAAAAAEA+AAAAAAAAgD4AAAAAAAAAPgAA
>gD4AAMA+AAAAPwAAAAAAAEA+AADAPgAAED8AAEA/AAAAAAAAgD4AAAA/AABAPwAAgD8=
></DataArray>
>      </PointData>
>      <CellData Scalars="exact">
><DataArray type="Float32" Name="exact" format="binary">
>QAAAAAAAgDwAAEA9AACgPQAA4D0AAEA9AAAQPgAAcD4AAKg+AACgPQAAcD4AAMg+AAAMPwAA
>4D0AAKg+AAAMPwAARD8=
></DataArray>
>      </CellData>
>      <Points>
><DataArray type="Float32" Name="Coordinates" NumberOfComponents="3" format="binary">
>LAEAAAAAAAAAAAAAAAAAAAAAgD4AAAAAAAAAAAAAAAAAAIA+AAAAAAAAgD4AAIA+AAAAAAAA
>AD8AAAAAAAAAAAAAAD8AAIA+AAAAAAAAQD8AAAAAAAAAAAAAQD8AAIA+AAAAAAAAgD8AAAAA
>AAAAAAAAgD8AAIA+AAAAAAAAAAAAAAA/AAAAAAAAgD4AAAA/AAAAAAAAAD8AAAA/AAAAAAAA
>QD8AAAA/AAAAAAAAgD8AAAA/AAAAAAAAAAAAAEA/AAAAAAAAgD4AAEA/AAAAAAAAAD8AAEA/
>AAAAAAAAQD8AAEA/AAAAAAAAgD8AAEA/AAAAAAAAAAAAAIA/AAAAAAAAgD4AAIA/AAAAAAAA
>AD8AAIA/AAAAAAAAQD8AAIA/AAAAAAAAgD8AAIA/AAAAAA==
></DataArray>
>      </Points>
>      <Cells>
><DataArray type="Int32" Name="connectivity" format="binary">
>AAEAAAAAAAABAAAAAwAAAAIAAAABAAAABAAAAAUAAAADAAAABAAAAAYAAAAHAAAABQAAAAYA
>AAAIAAAACQAAAAcAAAACAAAAAwAAAAsAAAAKAAAAAwAAAAUAAAAMAAAACwAAAAUAAAAHAAAA
>DQAAAAwAAAAHAAAACQAAAA4AAAANAAAACgAAAAsAAAAQAAAADwAAAAsAAAAMAAAAEQAAABAA
>AAAMAAAADQAAABIAAAARAAAADQAAAA4AAAATAAAAEgAAAA8AAAAQAAAAFQAAABQAAAAQAAAA
>EQAAABYAAAAVAAAAEQAAABIAAAAXAAAAFgAAABIAAAATAAAAGAAAABcAAAA=
></DataArray>
><DataArray type="Int32" Name="offsets" format="binary">
>QAAAAAQAAAAIAAAADAAAABAAAAAUAAAAGAAAABwAAAAgAAAAJAAAACgAAAAsAAAAMAAAADQA
>AAA4AAAAPAAAAEAAAAA=
></DataArray>
><DataArray type="UInt8" Name="types" format="binary">
>EAAAAAkJCQkJCQkJCQkJCQkJCQk=
></DataArray>
>      </Cells>
>    </Piece>
>  </UnstructuredGrid>
></VTKFile>
>  
>
>------------------------------------------------------------------------
>
>_______________________________________________
>ParaView mailing list
>ParaView at paraview.org
>http://www.paraview.org/mailman/listinfo/paraview
>  
>



More information about the ParaView mailing list