Question

I’m trying to start using emgu CV open CV for C#. But I’m having trouble making it work.
I’m following this guide to make simple program using emgu CV Link but I get following error: (any idea what I’m doing wrong?)

    System.TypeInitializationException was unhandled
      Message=The type initializer for 'Emgu.CV.CvInvoke' threw an exception.
      Source=Emgu.CV
      TypeName=Emgu.CV.CvInvoke
      StackTrace:
       at Emgu.CV.Image`2..ctor(String fileName) in c:\Emgu\emgucv-windows-x86-gpu 2.4.2.1777\Emgu.CV\Image.cs:line 144
       at TEST.Form1.button1_Click(Object sender, EventArgs e) in c:\documents and settings\laci\my documents\visual studio 2010\Projects\TEST\TEST\Form1.cs:line 28
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ButtonBase.WndProc(Message& m)
       at System.Windows.Forms.Button.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at TEST.Program.Main() in c:\documents and settings\laci\my documents\visual studio 2010\Projects\TEST\TEST\Program.cs:line 18
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.DllNotFoundException
       Message=Unable to load DLL 'opencv_core242': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
       Source=Emgu.CV
       TypeName=""
       StackTrace:
            at Emgu.CV.CvInvoke.cvRedirectError(CvErrorCallback errorHandler, IntPtr userdata, IntPtr prevUserdata)
            at Emgu.CV.CvInvoke..cctor() in c:\Emgu\emgucv-windows-x86-gpu 2.4.2.1777\Emgu.CV\PInvoke\CvInvoke.cs:line 166
       InnerException: 

Answer 1

Since Emgu.CV is just a .NET wrapper (see http://en.wikipedia.org/wiki/Wrapper_library), you need to put the native .DLL files of OpenCV in your application output directory.

You can find the required files by downloading the corresponding version of OpenCV at http://sourceforge.net/projects/opencvlibrary/files/opencv-win/2.4.2/OpenCV-2.4.2.exe/download