benn's profile - activity

It's possible, is there a way to check if opencv_contrib is installed and/or if python's path is not pointing to it?

I have a perfectly good opencv 3 installation on debian 8.5, and can use it via python or c++, and even works with my webcams.

The problem is that it doesn't have opencv_contrib, and I can't figure out how to add it. When I do the following, it complains of missing gstreamer and vtk packages:

  cmake -D CMAKE_BUILD_TYPE=RELEASE -D    CMAKE_INSTALL_PREFIX=/usr/local -D INSTALL_C_EXAMPLES=OFF -D INSTALL_PYTHON_EXAMPLES=ON -D OPENCV_EXTRA_MODULES_PATH=../opencv_contrib/modules -D BUILD_EXAMPLES=ON .

The output of the compile is here:

http://pastebin.com/2mfx6Yvg

Maybe it can't find it during build, but I did verify that gstreamer and vtk are installed.. these are the packages that are also installed:

kernel 3.16, gcc 4.9.2, python 2.7.9, opencv 3.1, vtk 6.1.0, QtCore 4.8.6, pyqt 4.11.2 (sip 4.16.4), matplotlib 1.5.2, scipy 0.18.0, skimage 0.12.3, IPython 2.3.0, sympy 1.0, dlib 19.1.0, h5py 2.6, progressbar 2.3, scikit-learn 0.17.1, cPickle 1.71

What could be the problem?

I've been struggling with a simple hello-world style opencv application in c++, and while it compiles fine, it wouldn't link due to unresolved references to any cv function (OutputArray, waitKey, etc)

From what I've read,

 http://answers.opencv.org/question/25708/undefined-symbols-cv_outputarray_outputarraystd__1vectorcvmat-std__1allocatorcvmat/

the problem seemed to be a difference between how OpenCV was originally built on the VM, and how my application is being built

(
The VM I'm using is
https://github.com/razius/ppy-opencv-vagrant  (Ubuntu 14.04.5 / OpenCV 2.4.13))
https://github.com/dvreed77/vagrant-opencv
)

I WAS trying to build the application this way,

g++ -O2 `pkg-config --cflags --libs opencv` test.cpp -o test.out

but changing it to this, the linker suddenly builds fine:

g++ -O2 -o test.out test.cpp `pkg-config opencv --cflags --libs`

What is happening differently that makes it work?

Good catch, I'm using backticks in the code. Interestingly, when I do the pkg-config line alone (no file) I get an unexpected warnings about lame!

ex. libmp3lame.so.0 needed by //usr/lib/arm-linux-gnueabihf/libavcodec.so not found http://pastebin.com/dLWJaCed

Why is it looking for lame/mp3 files to compile what would be opencv?

I understand opencv is installed on the stock debian 8.4 distro included with the beaglebone black:
i.e. pkg-config --modversion opencv returns 2.4.9.1

However, when I try to compile a simple hello-world test file:
g++ -O2 'pkg-config --cflags --libs opencv' test.cpp -o test

I get an error that there is no such file or directory for opencv,
g++: error: pkg-config --cflags --libs opencv: No such file or directory

I'm running as root, but is there someother setup (path, folder permissions) that need to be done?

I'm following the tutorial/code directly from here: http://derekmolloy.ie/beaglebone/beag...

Thanks!