问题:

I'm new to opencv and using ubuntu 14.04, I'm confused of the difference with opencv, python-opencv, and libopencv, as I have libopencv and python-opencv installed in my system, but I there is no cv interface accessible, so I have to install opencv which is much hard than python-opencv and libopencv.

回答1:

libopencv is the debian/ubuntu package while python-opencv is the python wrapper and can be accessed using cv2 interface like COLDSPEED mentioned

回答2:

I would like to add to Andika's answer.

OpenCV is computer vision a library written using highly optimized C/C++ code. It makes use of multiprocessing in the background. It has a collection of a large number of algorithms tested and verifiend by the developers. The best thing about this is it's FREE under the BSD license.
libopencv is only a metapackage. These packages do not contain actual software, they simply depend on other packages to be installed. So libopencv is a metapackage which simply references one or more related packages which are loosely grouped together. It is dedicated for installing OpenCV in Ubuntu and Debian OS.
Python-OpenCV is the OpenCV library available as a wrapper with bindings for python. The link also shows how to install OpenCV in Ubuntu OS.