C shared library call error

Hi all,

I create a C shared library from a .m file and get .dll/.h/.lib files successfully. But when I try to call the library in Visual Studio 2008 I meet these problems:

“error LNK2001: unresolved external symbol mclGetMatrix_730_proxy”

“error LNK2001: unresolved external symbol array_ref_get_numeric_mxDouble_730_proxy”

Do you have any idea about this problem?

My MATLAB version: R2012a

MATLAB compiler: v717

Operating system: 64-bit windows 7

The main h file for the library:

#ifndef __libImageClean_h
#define __libImageClean_h 1

#if defined(__cplusplus) && !defined(mclmcrrt_h) && defined(__linux__)
#  pragma implementation "mclmcrrt.h"
#endif
#include "mclmcrrt.h"
#include "mclcppclass.h"
#ifdef __cplusplus
extern "C" {
#endif

#if defined(__SUNPRO_CC)
/* Solaris shared libraries use __global, rather than mapfiles
 * to define the API exported from a shared library. __global is
 * only necessary when building the library -- files including
 * this header file to use the library do not need the __global
 * declaration; hence the EXPORTING_<library> logic.
 */

#ifdef EXPORTING_libImageClean
#define PUBLIC_libImageClean_C_API __global
#else
#define PUBLIC_libImageClean_C_API /* No import statement needed. */
#endif

#define LIB_libImageClean_C_API PUBLIC_libImageClean_C_API

#elif defined(_HPUX_SOURCE)

#ifdef EXPORTING_libImageClean
#define PUBLIC_libImageClean_C_API __declspec(dllexport)
#else
#define PUBLIC_libImageClean_C_API __declspec(dllimport)
#endif

#define LIB_libImageClean_C_API PUBLIC_libImageClean_C_API

#else

#define LIB_libImageClean_C_API

#endif

/* This symbol is defined in shared libraries. Define it here
 * (to nothing) in case this isn't a shared library. 
 */
#ifndef LIB_libImageClean_C_API 
#define LIB_libImageClean_C_API /* No special import/export declaration */
#endif

extern LIB_libImageClean_C_API 
bool MW_CALL_CONV libImageCleanInitializeWithHandlers(
       mclOutputHandlerFcn error_handler, 
       mclOutputHandlerFcn print_handler);

extern LIB_libImageClean_C_API 
bool MW_CALL_CONV libImageCleanInitialize(void);

extern LIB_libImageClean_C_API 
void MW_CALL_CONV libImageCleanTerminate(void);

extern LIB_libImageClean_C_API 
void MW_CALL_CONV libImageCleanPrintStackTrace(void);

extern LIB_libImageClean_C_API 
bool MW_CALL_CONV mlxImageClean(int nlhs, mxArray *plhs[], int nrhs, mxArray *prhs[]);

#ifdef __cplusplus
}
#endif

#ifdef __cplusplus

/* On Windows, use __declspec to control the exported API */
#if defined(_MSC_VER) || defined(__BORLANDC__)

#ifdef EXPORTING_libImageClean
#define PUBLIC_libImageClean_CPP_API __declspec(dllexport)
#else
#define PUBLIC_libImageClean_CPP_API __declspec(dllimport)
#endif

#define LIB_libImageClean_CPP_API PUBLIC_libImageClean_CPP_API

#else

#if !defined(LIB_libImageClean_CPP_API)
#if defined(LIB_libImageClean_C_API)
#define LIB_libImageClean_CPP_API LIB_libImageClean_C_API
#else
#define LIB_libImageClean_CPP_API /* empty! */ 
#endif
#endif

#endif

extern LIB_libImageClean_CPP_API void MW_CALL_CONV ImageClean(int nargout, mwArray& E, const mwArray& Img, const mwArray& radian);

#endif
#endif

one of the cpp file:

#include "stdafx.h"
#include "libImageClean.h"
#include "mclmcrrt.h"
//#include "mclmcr.h"
#include "mclcppclass.h"
#include "matrix.h"
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <cv.h>
#include <cxcore.h>
#include <highgui.h>
#include <string.h>
#include <windows.h>

#define _abs(x) ((x) > 0?(x):-(x))
        
int _tmain(int argc, _TCHAR* argv[])
{
  char image_name[1024] = "C:\\Qualcomm\\100CASIO\\contact fps\\";
  char file_name1[1024];
  char file_name2[1024];
  int Num_F = 500;
  int channel;
  int i,j;
  IplImage* Img1 = NULL;
  IplImage* Img2 = NULL;
  int height,width;
  uchar threshold = 120;
  double* radian = new double[1]();
  radian[0] = 7;
  double* fps = new double[1]();
  double *sd = new double[Num_F]();

  for(int ii=1;ii<Num_F-1;i++)
  {
    sprintf(file_name1, "%s%d%s", image_name, ii, ".jpg");
    sprintf(file_name2, "%s%d%s", image_name, ii+1, ".jpg");
    if((Img1 = cvLoadImage(file_name1,1))==0)  //
    {
      printf("Can not read image1!");
      return -1;
    }  
    if((Img2 = cvLoadImage(file_name2,1))==0)  //
    {
      printf("Can not read image2!");
      return -1;
    }
    height = Img1->height;
    width = Img1->width;
    uchar *imagedata1 = (uchar*)Img1->imageData;
    uchar *imagedata2 = (uchar*)Img2->imageData;

    ImageThresh(imagedata1,threshold,width,height);
    ImageThresh(imagedata2,threshold,width,height);

    double *diffimage = new double[width*height]();

    for(j=0;j<height;j++)
    {
      for(i=0;i<width;i++)
      {
        diffimage[j*width+i] = _abs(imagedata1[j*width+i]-imagedata2[j*width+i]);

      }
    }

    // initialize
    if(!mclInitializeApplication(NULL,0) ) 
                { 
                        printf("Could not initialize the application!");
      return -1; 
                } 

    if(!libImageCleanInitialize())
          {
                        printf("Could not initialize libtestdiff!");
                        return -1; 
                }
    
    mwArray a(width,height,mxDOUBLE_CLASS);
    mwArray b(1,1,mxDOUBLE_CLASS);
    mwArray c(width,height,mxDOUBLE_CLASS);
    a.SetData(diffimage,width*height);
    b.SetData(radian,1);
    // call the function
    ImageClean(1,c,a,b);
    c.GetData(diffimage,width*height);
    // terminate the lib
          libImageCleanTerminate();
    // terminate MCR
                mclTerminateApplication();  

    sd[ii] = GetImageSum(diffimage,width,height);  
    delete[] diffimage;
    delete[] radian;
  }
  return 0;
}

Thanks.

Answer 1

[Kaustubha Govind]

Is your Visual Studio configured to compile a 32-bit executable perhaps? This won't work because the compiled shared library is a 64-bit binary, so you need to configure Visual Studio for a 64-bit target.

Answer 2

[Ruixue Zhang]

I did configure to 64-bit platform.

In 32-bit platform, the error will be like these

error LNK2019: unresolved external symbol "__declspec(dllimport) void __cdecl MyFourier(int,class mwArray &,class mwArray const &)" (__imp_?MyFourier@@YAXHAAVmwArray@@ABV1@@Z) referenced in function _wmain

error LNK2019: unresolved external symbol _libImageCleanTerminate referenced in function _wmain

error LNK2019: unresolved external symbol _libImageCleanInitialize referenced in function _wmain

Answer 3

[Ruixue Zhang]

I've fixed this problem. It linked to the wrong mclXXX.lib files which do not match my compiled lib. Thanks for your help.