[vtkusers] vtkPNMReader

[Luis Sainz Hermoso]

Dear vtkUsers,
	I'm reading an image using vtkPNMReader and I want to know how
many of the pixels of the image have the value 1. The output of the
vtkPNMReader is a vtkImageSampleCache and this object doesn't allow to
access to the value of the different points. How can I convert it to
vtkImageData or how can I know the value of the points of an image?. I've
tried using the method MakeImageToStructuredPoints but I get that the
NumberOfPoints of the StructuredPoints is 1.

	Any ideas would be appreciated.Thank you very much.

		Luis Sainz