function imagedata=improcess(filename,threshold); 
imagedata=double(imread(filename)); 
newbuf=imagedata; 
[M N]=size(imagedata); 
for i=1:1:M 
 for j=1:1:N 
  if imagedata(i,j)>threshold 
   newbuf(i,j)=255; 
  else 
   newbuf(i,j)=0; 
  end 
 end 
end 
imwrite(uint8(newbuf),'result.bmp'); 
return; 

mcc -W cpplib:pr_lib -T link:lib improcess.m

libeng.lib
libmat.lib
libmex.lib
mclmcrrt.lib
pr_lib.lib

#pragma comment(lib,"mclmcrrt.lib") 
#pragma comment(lib,"libmx.lib") 
#pragma comment(lib,"libmat.lib") 
#include "matrix.h" 
#include "stdafx.h" 
#include <iostream> 
#include "pr_lib.h" 

#pragma comment(lib,"pr_lib.lib")
#include "pr_lib.h"

int main(int argc, char* argv[]) 
{ 
 //初始化， 在C++调用matlab时，必须要进行初始化。 
 if( !pr_libInitialize()) 
 { 
  printf("Could not initialize !"); 
  return -1;  
 } 
 char f_name[10]="lenna.pgm"; 
//必须将lenna.pgm图像，拷贝到工程目录下 
 mwArray file_name(f_name);//'lenna.pgm' 
 mwArray m_threshold(1,1, mxDOUBLE_CLASS); 
 m_threshold(1,1)=128;//阈值为128 
 mwArray ImageData(512,512, mxDOUBLE_CLASS); 
 improcess(1,ImageData,file_name,m_threshold); 
//1,表示返回值的个数，ImageData用于接收返回值 
 printf("\n图像处理结束,已经图像以阈值128分割开！\n"); 
 double *resultdata=new double[512*512]; 
 ImageData.GetData(resultdata,512*512); 
 printf("\n已获得图像数据...\n"); 
 for(int i=0;i<512;i++) 
 { 
  for(int j=0;j<512;j++) 
  { 
   printf("%0.1f ",resultdata[512*i+j]); 
  } 
  printf("\n"); 
 } 
 delete []resultdata; 
 // 后面是一些终止调用的程序 
 // terminate the lib  
 pr_libTerminate();   
 return 0; 
} 

/*typedef enum
 {
 mxUNKNOWN_CLASS = 0,
 mxCELL_CLASS,
 mxSTRUCT_CLASS,
 mxLOGICAL_CLASS,
 mxCHAR_CLASS,
 mxVOID_CLASS,
 mxDOUBLE_CLASS,
 mxSINGLE_CLASS,
 mxINT8_CLASS,
 mxUINT8_CLASS,
 mxINT16_CLASS,
 mxUINT16_CLASS,
 mxINT32_CLASS,
 mxUINT32_CLASS,
 mxINT64_CLASS,
 mxUINT64_CLASS,
 mxFUNCTION_CLASS,
 mxOPAQUE_CLASS,
  mxOBJECT_CLASS}*/