[Insight-users] Which types of meshes canDeformableModelSimplexMesh load?

[Marcus Wallin]

I have, since my previous mail, done some more testing and realised that my
mesh did not consist of raw images with binary colors (i.e either black or
white). 

I've converted my mesh into a truly binary format, which I believe is
correct, but when I try to load my mesh (which now consists of a mesh.mhd
and a series of raw images representing a segmented organ in binary format)
I get an error and the program exits.

I've pinpointed the error to the file DeformableModelApplication.cxx: row
374 where the following call is made

   m_SimplexMeshViewer.SetSimplexMesh(vgrid);

Before exiting, the DeformableModelSimplexMesh application prints out these
numbers in the console

  Number of points = 1483
  Number of cells = 2962
  simplex Number of Points = 2962
  simplex Number of Points = 5926

which I assume means that a mesh was indeed created from the loaded images.

Can anyone give a hint as to why this error occurs?

Since I get this error, I cannot be certain whether my mesh is correct or
not with respect to all the parameters to set in the mesh.mhd header file.
Therefore it would be great if I could try the application with a
known-to-be-valid 3D-image/3D-mesh. Is there such testing data, and where
can this be found?

In a previous posting, regarding DeformableModelSimplexMesh, Leila Baghdadi
mentions "I believe I do have a little test file as well". Where can this
test file be found?

Thanks,

--
Marcus Wallin
Software Engineer
Chalmers University of Technology, Sweden



>>Thank you for your answers!

>>I hadn't realized that I used an old version of ITKApplications (v2.0.1).
>>Now I have the most recent ITKApp from CVS (since I had compile problems
>>with 2.2.0) and have also got your help document.

>>I followed your suggestion and created two 3D-images with a *.mhd header
>>file that points to a list of *.raw files that are the actual images
(binary
>>mask of the mesh and the actual patient images). However, when I follow
the
>>step-by-step guide and reach the step where the mesh is loaded, the
program
>>tells me the following errors:

>>"ERROR: In \VTK-4.4-LatestRelease\src\Graphics\vtkDecimatePro.cxx, line
148
>>vtkDecimatePro (046BE708): No data to decimate!"

>>and

>>"No points in grid"

>>Can you please suggest to me what the error might be?

>>I suspect that the error is in my "mesh.mhd", though I have no idea what
it
>>can be.


>>The contents of my "mesh.mhd" is:

>>NDims = 3
>>DimSize = 256 256 78
>>ElementSpacing = 1 1 1
>>Position = 0 0 0
>>ElementByteOrderMSB = False
>>ElementNumberOfChannels = 3
>>ElementType = MET_UCHAR
>>ElementDataFile = mesh.%04d.raw 0 77 1

>>Thanks,

>>--
>>Marcus Wallin
>>Software Engineer
>>Chalmers University of Technology, Sweden




-----Ursprungligt meddelande-----
>>>Fren: Leila baghdadi [mailto:baghdadi at sickkids.ca] 
>>>Skickat: den 14 oktober 2005 17:21
>>>Till: Marcus Wallin
>>>Kopia: insight-users at itk.org
>>>Dmne: Re: [Insight-users] Which types of meshes
>>>canDeformableModelSimplexMesh load?

>>>Marcus,

>>>I setup a little help document which you should be able to load and get
>>>the information you require, but it is probably not as comprehensive as
>>>one would hope mainly due to lack of time.

>>>1. currently, there is no support for loading an actual mesh to this
>>>program although it is in my to do list,

>>>2. you can read a binary image which is then sent to vtk marching cubes
>>>filter to create a mesh so that is why itkImageFileReader is used
>>>because you are supposed to read an image (not a mesh)

>>>3. you can load your image (i.e, MR or which modality) and then try to
>>>load your mesh over it (i.e, read the binary image which represents your
>>>initial model of the mesh)

>>>4. right now you can load a 3d image (check the itk documentation and I
>>>believe I do have a little test file as well), your image should have
>>>two components,
>>>  -- *.mhd (text file , header containing the name of the raw image)
>>>  -- *.raw

>>>5. I suggest you read through the references that help provides and make
>>>sure you are familiar with the concept of simplex meshes and their
>>>corresponding deformable models which was originally introduced by
>>>Herve Delingette of INRIA, France.

>>>Please let me know of any problems,

>>>enjoy ITK!

>>>Leila