[vtkusers] creating a negative

[David Gobbi]

Hi David,

Try using a negative ColorWindow, e.g.
SetColorWindow(-4095.0)
SetColorLevel(0)  (or SetColorLevel(2047.5) if the data is unsigned)

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

On Mon, 10 Sep 2001, David J. Netherway wrote:

> What is a simple way to create a negative image?
>
> I am currently using the vtkImageViewer to map 12 bit images using the
> SetColorWindow and SetColorLevel methods.
>
> I had a look for a suitable filter or mapper flag but was unsuccessful.
>
> I could set up specific lookup tables but I thought that there might be
> something simple for this purpose.
>
> Thanks, David