title: CMake build error with added header file - fatal error: file not found
body: <p>I used CMake to build C++ source files in Ubuntu 14.04.</p>
  
  <p>I has a main source file. This includes a header file, which contains a function in another source file.</p>
  
  <p>My main source file is DisplayImage.cpp, and my header file is Camera.h with a source file Camera.cpp.</p>
  
  <p>Every file is located in one folder. And I have a CmakeLists.txt:</p>
  
  <pre><code>cmake_minimum_required(VERSION 2.8)
  project( DisplayImage )
  find_package( OpenCV REQUIRED )
  add_executable( DisplayImage DisplayImage.cpp Camera.cpp )
  target_link_libraries( DisplayImage  ${OpenCV_LIBS} )
  </code></pre>
  
  <p>When I execute the command <code>cmake .</code> in the terminal, it configures successfully. After that, I execute command <code>make</code>, and I get a fatal error: </p>
  
  <pre><code>fatal error: Camera.h: No such file or directory
  </code></pre>
  
  <p>Please help me. Is my CmakeLists.txt wrong?</p>