[vtkusers] vtkImageCast in not working

[Pratheek Arora]

Hi
 I have to convert the unsigned short data into unsigned char for that I
am using the vtkImagecast,I have written the follweing code
  vtkImageCast *cast= vtkImageCast::New();
 cast->SetInput(blend->GetOutput())
 cast->SetOutputScalarTypeToUnsignedChar();
vtkTIFFWriter *tiffw = vtkTIFFWriter::New(); 
 tiffw->SetInput(cast->GetOutput());
tiffw->SetFilePrefix(ptr1); 
 tiffw->Write();

But In output I am getting the error that data must be unsigned char,
if you know anything then please let me know
I am waiting for your reply
thanks
prateek


PRATEEK ARORA
Wipro GE Medical Systems
John F Welch Technology Centre
Export Promotion Industrial Park,
Plot 122, Phase-2, Whitefield Road
Bangalore: 560066. 
phone 8412050 - 3178