OpenCV installation notes - make and configuration

I thought I need to google to learn how to detar the .tar.bz2 file.  But Mitchtech's Michael is kind enough to the newbies to list all the necessary commands.


Raspberry Pi + OpenCV POSTED BY MICHAEL ON JUN 14, 2012

http://mitchtech.net/raspberry-pi-opencv/

...

Next, pull down the source files for OpenCV using wget:

wget http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.3.1/OpenCV-2.3.1a.tar.bz2

Once finished downloading, extract the archive, remove the no longer needed archive (to save space), change directory to the top of the source tree, make a directory for the build, and change into it:

tar -xvjpf OpenCV-2.3.1a.tar.bz2


rm OpenCV-2.3.1a.tar.bz2


cd OpenCV-2.3.1/


mkdir build


cd build

Next, you will need to configure the build using cmake. If you aren’t sure about what options you want/need or are unfamiliar with cmake, this line will create a standard configuration:

cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D BUILD_PYTHON_SUPPORT=ON -D BUILD_EXAMPLES=ON ..

Alternatively, you can configure the build using a GUI interface. This can be helpful to build with support for additional OpenCV features. To use the cmake GUI, run:

cmake-gui ..

In the cmake GUI, click ‘configure’ to pre-populate the build options. Select or remove any desired features, then click ‘configure’ again, check the output and ensure that there are not any modules that cmake cannot find. If everything looks good, click ‘generate’ to create the makefiles, then close cmake-gui. Now we are ready to start the build! To compile, run make, then install with make install:

make


sudo make install

As you can see from the image, this will take a LONG time ... over four and a half hours to compile!

Finally, we need to make a few configurations for OpenCV. First, open the opencv.conf file with the following code:

sudo nano /etc/ld.so.conf.d/opencv.conf

Add the following line at the end of the file(it may be an empty file, that is ok) and then save it:

/usr/local/lib

Then edit the system-wide bashrc file:

sudo nano /etc/bash.bashrc

Add the following new lines to the end of the file:

PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig export PKG_CONFIG_PATH

Now that everything is installed and configured, on to the demos!  The C demos are here:

cd ~/opencv/OpenCV-2.3.1/build/bin

C demos in build/bin demos worth checking out (that don’t require a webcam):

convexhull

kmeans

drawing

The python demos are located in samples/python:

cd ~/opencv/OpenCV-2.3.1/build/bin

These demos also don’t require a webcam:

python ./minarea.py

python ./delaunay.py

python ./drawing.py

.END