title: Removing all installed OpenCV libs
body: <p>I'm running Kubuntu 11.10 (w/ KDE 4.8)</p>
  
  <p>Before you read all this : </p>
  
  <p>I just want to remove all traces of OpenCV from my system, so I can start afresh..</p>
  
  <p>The whole story</p>
  
  <p>I first installed python-opencv and libopencv (2.1 I think) from <a href="https://launchpad.net/~gijzelaar/+archive/opencv2">https://launchpad.net/~gijzelaar/+archive/opencv2</a> a long time ago. I only tried python-opencv at that time, which worked perfectly (I didn't attempt using C++ code using OpenCV)</p>
  
  <p>Then I recently tried to install OpenCV 2.3.1 from source, which got installed but while compiling my own C++ code (using OpenCV), it gave me errors about libgtk not installed and also broke my python opencv code which was running fine earlier</p>
  
  <p>So I installed the libgtk2-dev libraries and compiled and installed OpenCV 2.3.1 again.. </p>
  
  <p>The error still occured, so I deleted the untarred OpenCV directory from which I was running cmake, make ,etc.  I did NOT make uninstall (which I now realize was my mistake)</p>
  
  <p>and instead installed the ubuntu opencv 2.3 package (with all dependencies) from here : <a href="https://launchpad.net/~gijzelaar/+archive/opencv2.3">https://launchpad.net/~gijzelaar/+archive/opencv2.3</a></p>
  
  <p>Now the problem is I still get the same error when I compile my C++ code which includes OpenCV , and the error still points to my (deleted) OpenCV source folder :</p>
  
  <pre><code>OpenCV Error: Unspecified error (The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script) in cvNamedWindow, file /home/anant/opencv/OpenCV-2.3.1/modules/highgui/src/window.cpp, line 275
  terminate called after throwing an instance of 'cv::Exception'
    what():  /home/anant/opencv/OpenCV-2.3.1/modules/highgui/src/window.cpp:275: error: (-2) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script in function cvNamedWindow
  </code></pre>
  
  <p>As you can see the error still points to the directory from where I had compiled and installed OpenCV</p>
  
  <p>Is there a way to completely remove all traces of my compiled version of OpenCV and just keep the files from the ubuntu package? As I mentioned earlier I did not 'make uninstall' and have also (foolishly) deleted the install-manifest </p>
  
  <p><strong>EDIT:</strong>
  I ran the package manager again,and found that not all opencv packages from the ppa had gotten installed properly. So I did a sudo apt-get install opencv again, and now I get this error:</p>
  
  <pre><code>Unpacking libopencv2.3 (from .../libopencv2.3_2.3.1-3_amd64.deb) ...
  dpkg: error processing /var/cache/apt/archives/libopencv2.3_2.3.1-3_amd64.deb (--unpack):
   trying to overwrite '/usr/lib/libopencv_video.so.2.3.1', which is also in package libopencv-video2.3 2.3.1-4ppa1
  dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
  Unpacking opencv (from .../opencv_2.3.1-3_amd64.deb) ...
  dpkg: error processing /var/cache/apt/archives/opencv_2.3.1-3_amd64.deb (--unpack):
   trying to overwrite '/usr/bin/opencv_haartraining', which is also in package libopencv-core-dev 2.3.1-4ppa1
  dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
  Errors were encountered while processing:
   /var/cache/apt/archives/libopencv2.3_2.3.1-3_amd64.deb
   /var/cache/apt/archives/opencv_2.3.1-3_amd64.deb
  E: Sub-process /usr/bin/dpkg returned an error code (1)
  </code></pre>
  
  <p>I just want to remove all traces of OpenCV from my system, so I can start afresh</p>