At the beginning of my OpenCV learning with Python, I noticed one thing which confused me but I didn't give it further attentions. Some examples import the OpenCV modules by using ``import cv'' and some use ``import opencv.'' The first one has never worked to me, so I've adopted ``import opencv'' until today.
The problems were not only about the import approach. Although I found I can import opencv.cv module, which looked similar to the so-called cv module, there had been other problems about the function names. I noticed that many functions given by the opencv.cv module have the ``cv'' prefix, while the same functions given directly by the cv module don't. For example, opencv.cv offers open.cv.cvSomeFunction() while in cv it is cv.SomeFunction(). Based on the observation, I suspected that my installation of OpenCV an/or Python bindings are not totally right.