1. 環境：Win7（64位），opencv2.3，vs2010

2.程式碼：

///////////////////////////////////////////////////////////////////////////////////////////////////

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <fstream>
#include <string>
#include <iostream>
#include <opencv/cv.h>
#include <opencv/highgui.h>
using namespace std;
 
int main(int argc, char *argv[])
{
 
  IplImage* img = 0;
  int height,width,step,channels;
  uchar *data;
  int i,j,k;
 
  if(argc<2){
    printf("Usage: main <image-file-name>\n\7");
    exit(0);
  }
 
  // load an image 

  img=cvLoadImage(argv[1]);
  if(!img){
    printf("Could not load image file: %s\n",argv[1]);
    exit(0);
  }
 
  // get the image data
  height    = img->height;
  width     = img->width;
  //step      = img->widthStep;
  //channels  = img->nChannels;
  //data      = (uchar *)img->imageData;
  printf("Processing a %dx%d image with %d channels\n",height,width,channels);

  //build File to save pixel value
  ofstream outFile_B;
  ofstream outFile_G;
  ofstream outFile_R;
  outFile_B.open("out_B.txt");
  outFile_G.open("out_G.txt");
  outFile_R.open("out_R.txt");

   //get the pixel value

  CvScalar s;
  for(i=0;i<height;i++) //i 代表 y 軸
  {
     for(j=0;j<width;j++) //j 代表 x軸

     {
        s=cvGet2D(img,i,j); // get the (j,i) pixel value

       outFile_B<<s.val[0]<<" ";
       outFile_G<<s.val[1]<<" ";
       outFile_R<<s.val[2]<<" "; 
      }
      outFile_B<<endl;
      outFile_G<<endl;
      outFile_R<<endl;
  }
  return 0; 

}

3.實現

   用cmd執行：
    例如我的是：D:\\Projects\practice\Lena\x64\Debug〉Lena.exe "D:\\lena.bmp"

    實現截圖：

4.參考資料：