[Insight-users] Re: [Paraview] 3D Deformable Registration Deformation Field

[Luis Ibanez]

Hi Kevin,


Thanks a lot for sending the MetaImage header.

The line:

     ElementSpacing = 0.02 0.02 27

explains what we are seeing in ParaView.


The voxel size is about 1000 times larger
in the Z direction     :-/


ParaView is showing the reality of the data.



What you may want to verify now, is whether that
was the original pixel size of the images that
you were registering. In particular you should
look at the Fixed image.

Note that if that's the real spacing on the fixed
image... well... there is not hope for registering
such dataset, because it is a more of a rod than
it is a volume...   :-/


Please let us know what you find.


    Thanks



       Luis



-------------------
Kevin Ming wrote:
> Hi again Luis,
> 
> I've uploaded both "set5o_s_10_field.mhd" and "set5o_s_10_field.raw" to 
> Kitware Uploader for your convenience.
> 
> Also, for these, I used the Level Set Deformable Regsitration with 500 
> iterations.  I had to the extend it from the original 2D case to 3D, so 
> I probably did something wrong when I changed the section of the code 
> for producing the deformation field, causing the problem I have now.  I 
> obtained a near-perfect registration, though.
> 
> I hope this information is useful.
> 
> 
> Thank You,
> Kevin
> 
> 
> On 7/11/06, *Luis Ibanez* <luis.ibanez at kitware.com 
> <mailto:luis.ibanez at kitware.com>> wrote:
> 
> 
>     Hi Kevin,
> 
>     Thanks for posting the screenshots of the deformation field
>     visualizations.
> 
>     Your verbal description was accurate.  Therefore, there is
>     definitely something wrong going on with the deformable
>     registration process.
> 
>     Could you please post the .mhd files of your deformation
>     fields ?
> 
>     like "set50_s_10_field.mhd"
> 
>     Those are the text headers of the MetaImage format, they
>     should give us an idea of the number of pixels in the 3D
>     deformation field as well as the pixel size in 3D.
> 
> 
>        Thanks
> 
> 
>           Luis
> 
> 
> 
>     --------------------
>     Kevin Ming wrote:
>      > Hi,
>      >
>      > I was able to get a deformation field output from my 3D deformable
>      > registration, but it's not what I was expecting to see:  There
>     seem to
>      > be 64 sets of arrows, which is good because it corresponds to the 64
>      > slices of MRI data I used.  But each of the sets of arrows,
>     supposedly
>      > from each of the slices, seem to originate from a single point on a
>      > line.  I was expecting to see the field in a manner similar to
>     that of
>      > the 2D deformable registration examples, where arrows are located
>     on the
>      > images in plane, showing what features have moved and where they
>     have
>      > moved to.  Is it possible to get that in the 3D case?  Are there
>     other
>      > ways of visualizing 3D deformation fields in ParaView?
>      >
>      > Note that my fixed, moving, and output images for the
>     registration are
>      > in the ANALYZE format (.hdr and .img files) and my deformation
>     field is
>      > in the Meta image file format (.mhd and .raw files).
>      >
>      >
>      > Thank You,
>      > Kevin
>      >
>      >
>      >
>     ------------------------------------------------------------------------
> 
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>