title: Qt Creator cannot find openCV libraries
body: <p>First of all I know this question has been asked <a href="https://stackoverflow.com/questions/16710047/usr-bin-ld-cannot-find-lnameofthelibrary">(see here)</a> but those solutions did not work for me.</p>
  
  <p>I am trying to install opencv to use with Qt Creator on ubuntu 14.04. </p>
  
  <p>I followed <a href="http://rodrigoberriel.com/2014/10/installing-opencv-3-0-0-on-ubuntu-14-04/" rel="nofollow noreferrer">this</a> tutorial exactly and confirmed that it worked by running the facedetect example. </p>
  
  <p>I then started on <a href="http://rodrigoberriel.com/2014/11/using-opencv-3-qt-creator-3-2-qt-5-3/" rel="nofollow noreferrer">this</a> tutorial for using Qt creator with opencv. I followed the steps in the video exactly, however when I build and run the example I get the following errors: </p>
  
  <pre><code>   /usr/bin/ld: cannot find -lopencv_core
     /usr/bin/ld: cannot find -lopencv_imgcodecs
     /usr/bin/ld: cannot find -lopencv_highgui
  </code></pre>
  
  <p>full compile output: </p>
  
  <pre><code>g++ -Wl,-rpath,/home/tpst/Program_Files/Qt-5.3.1/5.3/gcc_64 -Wl,-rpath,/home/tpst/Program_Files/Qt-5.3.1/5.3/gcc_64/lib -o test main.o   -L/usr/local/lib -lopencv_core -lopencv_imgcodecs -lopencv_highgui -L/home/tpst/Program_Files/Qt-5.3.1/5.3/gcc_64/lib -lQt5Core -lpthread 
  /usr/bin/ld: cannot find -lopencv_core
  /usr/bin/ld: cannot find -lopencv_imgcodecs
  /usr/bin/ld: cannot find -lopencv_highgui
  collect2: error: ld returned 1 exit status
  make: *** [test] Error 1
  23:02:50: The process "/usr/bin/make" exited with code 2.
  Error while building/deploying project test (kit: Desktop Qt 5.3 GCC 64bit)
  When executing step 'Make'
  </code></pre>
  
  <p>And here is the contents of my .pro file: </p>
  
  <pre><code>QT       += core
  
  QT       -= gui
  
  TARGET = test
  CONFIG   += console
  CONFIG   -= app_bundle
  
  TEMPLATE = app
  
  INCLUDEPATH += /usr/local/include/opencv
  LIBS += -L/usr/local/lib -lopencv_core -lopencv_imgcodecs -lopencv_highgui
  
  SOURCES += main.cpp
  </code></pre>
  
  <p>I have also tried to compile using terminal and get the same (/usr/bin/ld: cannot find -llib)</p>
  
  <p>I dont understand why Qt cant find the libraries. You can see that they exist in the directory <img src="https://i.imgur.com/PAZhjxx.png" alt="here"></p>
  
  <p>Some help would be appreciated. I'm new to linux and Qt, I dont really understand the solutions posted to similar questions and have not been able to solve this myself. </p>