Interpolation of Textures

[David Gobbi]

Hi Sathya,

I don't know of any efficient way to do better than linear-interpolation
in texture maps, but here's an inefficient method:

Put the image through vtkImageReslice, using
reslice SetOutputSpacing 0.25 0.25 0.25
reslice SetInterpolationModeToCubic

to use cubic interpolation to resample the image to 4X detail.  Then
texture map the result.

An even less efficent solution (but providing even better results) is to
fourier-transform the image, pad it to 4X original size, and reverse
fourier-transform.  This provides sinc interpolation.  

 - David

--David Gobbi, MSc                    dgobbi at irus.rri.on.ca
  Advanced Imaging Research Group
  Robarts Research Institute, University of Western Ontario

On Mon, 13 Sep 1999, Will Schroeder wrote:

> Hi Sathya / Ron-
> 
> The input to vtkTexture is image data - so you can always use vtk image processing filters (such as bilinear interpolation, etc.) to process the texture map.
> 
> Will
> 
> 
> At 10:22 PM 9/13/99 +0200, Ron Inbar wrote:
> >OpenGL only supports linear interpolation, and this feature is implemented
> >in almost every 3D graphics card, so I guess we're not likely to see other
> >kinds of interpolation in VTK.  Anyway, I don't see how other kinds of
> >texture interpolation may improve the image quality.
> >
> >Ron
> >
> >----- Original Message -----
> >From: Sathya <ksathya at omirf.iusd.iupui.edu>
> >To: Vtkusers <vtkusers at gsao.med.ge.com>
> >Cc: <manaloui at iupui.edu>
> >Sent: Monday, September 13, 1999 16:05
> >Subject: Interpolation of Textures
> >
> >
> > > Hello All
> > >
> > > Is there anyway to have other kinds of Interpolation in vtkTexture ?
> > > vtkTexture currently has linear interpolation.
> > >
> > > Thanks.
> > > cheers
> > > ~Sathya
> > >
> > > Sathya Krishnamurthy
> > > Res: 317-630-5412
> > > Off: 317-278-1357
> > > http://omirf.iusd.iupui.edu/~ksathya
> > >
> > >
> > >
> > > --------------------------------------------------------------------------
> >---
> > > 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.
> > > --------------------------------------------------------------------------
> >---
> > >
> > >
> >
> >
> >
> >-----------------------------------------------------------------------------
> >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.
> >-----------------------------------------------------------------------------
> 
> 
> 
> -----------------------------------------------------------------------------
> 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.
> -----------------------------------------------------------------------------
> 



-----------------------------------------------------------------------------
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.
-----------------------------------------------------------------------------