Open Computer Vision Library

When trying to use cvCalcBackProject, I get the following error using
Python:

Traceback (most recent call last):
File "back_proj.py", line 67, in <module>

cv.cvCalcBackProject([blue_channel,green_channel,red_channel],samp_rect,his
t)
File "/usr/local/lib/python2.5/site-packages/opencv/cv.py", line 1059, in
cvCalcBackProject
return _cv.cvCalcBackProject(*args)
TypeError: in method 'cvCalcBackProject', argument 1 of type 'IplImage *'

I can't pass in the type for the first argument that the function requires.
I think that it should need a list or tuple, but it seems to require a
pointer, which I can't provide from Python.