opencv实践程序5——最简单背景差分法

//最简单背景差分法
#include <stdio.h>
#include <cv.h>
#include <highgui.h>

int main( int argc, char** argv )
{
  //声明IplImage指针
  IplImage* pFrame = NULL;
  IplImage* pFrImg = NULL;
  IplImage* pBkImg = NULL;

  CvMat* pFrameMat = NULL;
  CvMat* pFrMat = NULL;
  CvMat* pBkMat = NULL;
 
  CvCapture* pCapture = NULL;
 
  int nFrmNum = 0;
   
  //创建窗口
  cvNamedWindow("video", 1);
  cvNamedWindow("background",1);
  cvNamedWindow("foreground",1);
  //使窗口有序排列
  cvMoveWindow("video", 30, 0);
  cvMoveWindow("background", 360, 0);
  cvMoveWindow("foreground", 690, 0);
  
  pCapture = cvCaptureFromCAM(0);//从摄像头读入

    //逐帧读取视频
     while(pFrame = cvQueryFrame( pCapture ))
    {
         nFrmNum++;
     
         //如果是第一帧，需要申请内存，并初始化
         if(nFrmNum == 1)
        {
           
            pBkImg = cvCreateImage(cvSize(pFrame->width, pFrame->height),
                IPL_DEPTH_8U,1);
           pFrImg = cvCreateImage(cvSize(pFrame->width, pFrame->height), 
                IPL_DEPTH_8U,1);
            pBkMat = cvCreateMat(pFrame->height, pFrame->width, CV_32FC1);
           pFrMat = cvCreateMat(pFrame->height, pFrame->width, CV_32FC1);
           pFrameMat = cvCreateMat(pFrame->height, pFrame->width, CV_32FC1);

           //转化成单通道图像再处理
           cvCvtColor(pFrame, pBkImg, CV_BGR2GRAY);
           cvCvtColor(pFrame, pFrImg, CV_BGR2GRAY);

           cvConvert(pFrImg, pFrameMat);
           cvConvert(pFrImg, pFrMat);
           cvConvert(pFrImg, pBkMat);
      }
         else
      {
           cvCvtColor(pFrame, pFrImg, CV_BGR2GRAY);
           cvConvert(pFrImg, pFrameMat);
           //先做高斯滤波，以平滑图像
           //cvSmooth(pFrameMat, pFrameMat, CV_GAUSSIAN, 3, 0, 0);
     
           //当前帧跟背景图相减
           cvAbsDiff(pFrameMat, pBkMat, pFrMat);

           //二值化前景图
           cvThreshold(pFrMat, pFrImg, 60, 255.0, CV_THRESH_BINARY);

           //进行形态学滤波，去掉噪音 
          //cvErode(pFrImg, pFrImg, 0, 1);
           //cvDilate(pFrImg, pFrImg, 0, 1);

           //更新背景
           cvRunningAvg(pFrameMat, pBkMat, 0.003, 0);
           //将背景转化为图像格式，用以显示
           cvConvert(pBkMat, pBkImg);

           //显示图像
         //  pFrImg->origin=1;         //  根据网友意见整改
          // pBkImg->origin=1;
           //cvFlip(pBkImg,NULL,0);    // 也可         
                   
           cvShowImage("video", pFrame);
           cvShowImage("background", pBkImg);
           cvShowImage("foreground", pFrImg);

           //如果有按键事件，则跳出循环
           //此等待也为cvShowImage函数提供时间完成显示
           //等待时间可以根据CPU速度调整
         
          if( cvWaitKey(2) >= 0 )
             break;

      }  // end of if-else
    } // end of while-loop

     //销毁窗口
     cvDestroyWindow("video");
     cvDestroyWindow("background");
     cvDestroyWindow("foreground");

     //释放图像和矩阵
     cvReleaseImage(&pFrImg);
     cvReleaseImage(&pBkImg);

     cvReleaseMat(&pFrameMat);
     cvReleaseMat(&pFrMat);
     cvReleaseMat(&pBkMat);

     cvReleaseCapture(&pCapture);
     return 0;
}