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<DIV><SPAN class=938095109-21102009><FONT size=2 
face=Arial>Hi</FONT></SPAN></DIV>
<DIV><SPAN class=938095109-21102009><FONT size=2 
face=Arial></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=938095109-21102009><FONT size=2 face=Arial>I want to compare 
two images using the vtkImageCheckerboard function. The problem is that i have 
two images of odd size (512x512x80 and 512x512x60). The strange thing 
is:</FONT></SPAN></DIV>
<DIV><SPAN class=938095109-21102009><FONT size=2 
face=Arial></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=938095109-21102009><FONT size=2 face=Arial>When I 
use</FONT></SPAN></DIV>
<DIV><FONT size=2 face=Arial></FONT>&nbsp;</DIV>
<DIV>
<P><FONT size=2>m_Checkerboard-&gt;SetInput(0, vtkImage1);<SPAN 
class=938095109-21102009>//bigger image</SPAN></FONT></P>
<P><FONT size=2>m_Checkerboard-&gt;SetInput(1, vtkImage2);&nbsp;<SPAN 
class=938095109-21102009>//smaller image</SPAN></FONT></P>
<P><FONT size=2 face=Arial><SPAN class=938095109-21102009>i get a null pointer 
exception (after Update()), when i use</SPAN></FONT></P><SPAN 
class=938095109-21102009>
<P><FONT size=2>m_Checkerboard-&gt;SetInput(0, vtkImage<SPAN 
class=938095109-21102009>2</SPAN>);<SPAN class=938095109-21102009>//smaler 
image</SPAN></FONT></P>
<P><FONT size=2>m_Checkerboard-&gt;SetInput(1, vtkImage<SPAN 
class=938095109-21102009>1</SPAN>);&nbsp;<SPAN class=938095109-21102009>//bigger 
image</SPAN></FONT></P></SPAN>
<P><FONT size=2><SPAN class=938095109-21102009><FONT face=Arial>it works. Is 
there a function/method</FONT>&nbsp;<FONT face=Arial>to scale one image to the 
size of the second image so that the process works for arbitrary images to 
compare?</FONT></SPAN></FONT></P>
<P><FONT size=2 face=Arial><SPAN class=938095109-21102009>best 
regards,</SPAN></FONT></P>
<P><FONT size=2 face=Arial><SPAN 
class=938095109-21102009>Gerald</SPAN></FONT></P></DIV></BODY></HTML>