Running OpenCV from a Python virtualenv

Question

I'm trying to install OpenCV within a virtualenv on my Ubuntu Server 12.04. I found a thread discussing this but managed to extract no information from it.

I tried using pip install pyopencv but it failed.

...
package/extras/core/ndarray.cpp:598:1:   instantiated from here

package/extras/core/ndarray.cpp:546:9: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘Py_intptr_t {aka long int}’ [-Wformat]

package/extras/core/ndarray.cpp: In function ‘boost::python::api::object sdcpp::from_ndarray_impl(const sdcpp::ndarray&) [with T = cv::Scalar_<double>]’:

package/extras/core/ndarray.cpp:601:1:   instantiated from here

package/extras/core/ndarray.cpp:546:9: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘Py_intptr_t {aka long int}’ [-Wformat]

package/extras/core/ndarray.cpp: In function ‘boost::python::api::object sdcpp::from_ndarray_impl(const sdcpp::ndarray&) [with T = cv::Range]’:

package/extras/core/ndarray.cpp:604:1:   instantiated from here

package/extras/core/ndarray.cpp:546:9: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘Py_intptr_t {aka long int}’ [-Wformat]

error: command 'gcc' failed with exit status 1

This error only occurs the second time I run pip install. If I delete the remainging build/ folder I get this error.

-- Configuring incomplete, errors occurred!

Configuring PyOpenCV via CMake...

Error: error occurred while running CMake to configure PyOpenCV.

You may want to manually configure PyOpenCV by running cmake's tools:

    mkdir build

    cd build

    cmake-gui ..    OR    cmake ..

    cd ..

----------------------------------------
Command python setup.py egg_info failed with error code 255

I have at least the following apt packages installed.

build-essential
uuid-dev
python-dev
python-pip
libpq-dev
cmake
libboost-dev
libcv-dev
libcvaux-dev
libboost-python-dev
libboost1.48-dev

How can I install OpenCV within my virtualenv?

Answer 1

Fired up a virtualenv and followed this guide: http://www.samontab.com/web/2011/06/installing-opencv-2-2-in-ubuntu-11-04/ , up until manipulating and copying the cv shared objects. Instead, I copied cv.so (from my OpenCV-2.2.0/lib directory) to my virtualenv site-packages (eg. env/lib/python2.7/site-packages/). Once cv.so was in my environment, I was able to import cv within python.