• please add the cmake output to your question
• if there are any errors, we need to see them, too !
• what are you trying to do with the face-recognition ?

Output: (con) --There are no errors and its configured completely too. -- working in windows but not ubuntu. I need it to be in ubuntu. -- Doing an application which recognizes the faces for that i need face-recognition class.

we cannot help you, if all you can say is: "does not work"

I have followed the below link for installation of opencv and opencv-contrib and used java language as building the application. can you find out anything is wrong in these commands.

https://www.learnopencv.com/install-o...

showing tutorials you tried to follow is entirely useless. we need to know, what YOU did, not someone else.

sudo apt-get update sudo apt-get upgrade

sudo apt-get remove x264 libx264-dev

sudo apt-get install build-essential checkinstall cmake pkg-config yasm gfortran git sudo apt-get install libjpeg8-dev libjasper-dev libpng12-dev

If you are using Ubuntu 14.04

sudo apt-get install libtiff4-dev sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libdc1394-22-dev sudo apt-get install libxine2-dev libv4l-dev sudo apt-get install libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev sudo apt-get install libqt4-dev libgtk2.0-dev libtbb-dev sudo apt-get install libatlas-base-dev sudo apt-get install libfaac-dev libmp3lame-dev libtheora-dev sudo apt-get install libvorbis-dev libxvidcore-dev sudo apt-get install libopen

sudo apt-get install libprotobuf-dev protobuf-compiler sudo apt-get install libgoogle-glog-dev libgflags-dev sudo apt-get install libgphoto2-dev libeigen3-dev libhdf5-dev doxygen

Download opencv & opencv_contrib from Github

git clone https://github.com/opencv/opencv.git cd opencv git checkout 3.3.0 cd ..

git clone https://github.com/opencv/opencv_cont... cd opencv_contrib git checkout 3.3.0 cd ..

cd opencv mkdir build cd build

cmake -D CMAKE_BUILD_TYPE=RELEASE \ -D CMAKE_INSTALL_PREFIX=/usr/local \ -D INSTALL_C_EXAMPLES=ON \ -D INSTALL_PYTHON_EXAMPLES=ON \ -D WITH_TBB=ON \ -D WITH_V4L=ON \ -D WITH_QT=ON \ -D WITH_OPENGL=ON \ -D OPENCV_EXTRA_MODULES_PATH=/home/venkatesh/OPENCV2/opencv_contrib/modules \ -D BUILD_EXAMPLES=ON

Compile and Install

nproc
make -j4
sudo make install
sudo sh -c 'echo "/usr/local/lib" >> /etc/ld.so.conf.d/opencv.conf'
sudo ldconfig

cmake output

OpenCV modules: -- To be built:
core flann hdf imgproc ml objdetect phase_unwrapping photo plot reg surface_matching video viz xphoto bgsegm dnn face freetype fuzzy img_hash imgcodecs shape videoio xobjdetect highgui superres ts bioinspired dpm features2d line_descriptor saliency text calib3d ccalib datasets rgbd stereo structured_light tracking videostab xfeatures2d ximgproc aruco java optflow sfm stitching python2
-- Disabled: world contrib_world
-- Disabled by dependency: -
-- Unavailable: cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev python3 cnn_3dobj cvv dnn_modern matlab

GUI:
-- QT 4.x: YES (ver 4.8.6 EDITION = OpenSource)
-- QT OpenGL support: YES (/usr/lib/x86_64-linux-gnu/libQtOpenGL.so)
-- OpenGL support: YES (/usr/lib/x86_64-linux-gnu/libGLU.so /usr/lib/x86_64-linux-gnu/libGL.so
/usr/lib/x86_64-linux-gnu/libSM.so /usr/lib/x86_64-linux-gnu/libICE.so /usr/lib/x86_64-linux-gnu/libX11.so /usr/lib/x86_64-linux-gnu/libXext.so)

-- VTK support: YES (ver 5.8.0)

-- Media I/O:
-- ZLib: /usr/lib/x86_64-linux-gnu/libz.so (ver 1.2.8)
-- JPEG: /usr/lib/x86_64-linux-gnu/libjpeg.so (ver )
-- WEBP: build (ver encoder: 0x020e)