【OpenCV学习】运动检测实例

/**************************************************
 * 背景建模，运动物体检测
 *     
 **************************************************/
/***********************************************************************
 * OpenCV example
 * By Shiqi Yu 2006
 ***********************************************************************/

#include <stdio.h>
#include <cv.h>
#include <cxcore.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);

  if( argc > 2 )
    {
      fprintf(stderr, "Usage: bkgrd [video_file_name]/n");
      return -1;
    }
  //打开摄像头
  if (argc ==1)
    if( !(pCapture = cvCaptureFromCAM(-1)))
      {
    fprintf(stderr, "Can not open camera./n");
    return -2;
      }
  //打开视频文件
  if(argc == 2)
    if( !(pCapture = cvCaptureFromFile(argv[1])))
      {
    fprintf(stderr, "Can not open video file %s/n", argv[1]);
    return -2;
      }
 
  //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
      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;

    }
    }
   

  //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;
}