Optimizations

[Sebastien Barre]

<x-flowed>At 14:55 14/01/00 -0500, Sathya Krishnamurthy a écrit:

>I would like to get feedback from the vtkusers on What are the
>optmizations that can be done for doing Surface Rendering of CT Data. I
>have CT data in a set of PPM files. I am reading them and using
>ImageMarchingCubes to generate the surface and then using vtkImageReslice
>to extract the individual slices axial, coronal and sagittal..slices..

I posted something about that last week... Regarding the 3D reconstruction 
(surface), here is my pipeline :

         - Image/Volume16Reader
         - MarchingCubes/SliceCubes
         - CleanPolyData
         - [PolyDataConnectivityFilter]
         - [SmoothPolyDataFilter]
         - Decimate[Pro]
         - [SmoothPolyDataFilter]
         - [Transform]
         - [PolyDataNormals]
         - [Stripper]

On my Pentium II, 300 Mhz, 196 RAM, reconstructing the "bones" for a tissue
thresholded at 1190 (not segmented sadly) from 240 CT slices (224x224
pixels) takes approx. 6 minutes :

bone reader:        13 s. => 13 s.
bone mcubes:        25 s. => 38 s. (942668 polys, 471700 points)
bone cleaner:       13 s. => 51 s. (942668 polys, 471682 points)
bone connect:       9 s. => 60 s. (902114 polys, 471682 points)
bone smoother 1:    133 s. => 194 s. (902114 polys, 471682 points)
bone decimator pro: 129 s. => 323 s. (360844 polys, 178954 points)
bone smoother 2:    52 s. => 375 s. (360844 polys, 178954 points)
bone transformer:   0 s. => 375 s.
bone normals:       18 s. => 394 s.
bone stripper:      3 s. => 397 s. (100177 strips, 265443 points)
bone writer:        2 s. => 399 s.



-----------------------------------------------------------------------------
This is the private VTK discussion list.  Please keep messages on-topic.
Check the FAQ at: <http://www.automatrix.com/cgi-bin/vtkfaq>
To UNSUBSCRIBE, send message body containing "unsubscribe vtkusers" to
<majordomo at gsao.med.ge.com>.  For help, send message body containing
"info vtkusers" to the same address.     Live long and prosper.
-----------------------------------------------------------------------------

</x-flowed>