C++ OpenCV视频操作之CamShift跟踪算法

#include <opencv2/opencv.hpp>
#include <iostream>

cv::Mat frame, gray; //源图像和源灰度图像
cv::Mat framecopy;  //用于拷贝出的源图像
cv::Mat framerect, framerecthsv;  //矩形选取后的图像
cv::Rect rect;      //鼠标选取的矩形

//直方图
int histSize = 200;
float histR[] = { 0,255 };
const float *histRange = histR;
int channels[] = { 0,1 };
cv::Mat dstHist;

//保存目标轨迹  
std::vector<cv::Point> pt;

//鼠标控制
bool firstleftbutton = false;
bool leftButtonDownFlag = false; //左键单击后视频暂停播放的标志位 
cv::Point rectstartPoint; //矩形框起点    
cv::Point rectstopPoint; //矩形框终点    
void onMouse(int event, int x, int y, int flags, void* ustc); //鼠标回调函数    


int main(int argc, char** argv)
{
  cv::VideoCapture video;
  video.open("E:/KK_Movies/test5.mp4");
  if (!video.isOpened())
  {
    printf("could not open video....\r\n");
    getchar();
    return -1;
  }
  double fps = video.get(CV_CAP_PROP_FPS); //获取视频帧率    
  double pauseTime = 1000 / fps; //两幅画面中间间隔    
  cv::namedWindow("srcvideo", CV_WINDOW_NORMAL);
  //设置图像中鼠标事件
  cv::setMouseCallback("srcvideo", onMouse, 0);
  bool first = false;
  while (true)
  {
    //当鼠标左键没有按下时
    if (!leftButtonDownFlag)
    {
      video >> frame;
      try
      {
        cv::resize(frame, frame, cv::Size(300, 600));
      }
      catch (const std::exception& exception)
      {
        printf(exception.what());
        break;
      }
    }
    //图像为空或Esc键按下退出播放    
    if (!frame.data || cv::waitKey(pauseTime) == 27)
    {
      break;
    }
    //如果已经截取了图像进行处理
    if (rectstartPoint != rectstopPoint && !leftButtonDownFlag)
    {
      cv::Mat imageHSV;
      cv::Mat calcBackImage;
      cvtColor(frame, imageHSV,  cv::COLOR_BGR2HSV);

      //反向投影
      cv::calcBackProject(&imageHSV, 2, channels, 
        dstHist, calcBackImage, &histRange);
      cv::TermCriteria criteria(cv::TermCriteria::MAX_ITER +
        cv::TermCriteria::EPS, 10, 1);
      cv::CamShift(calcBackImage, rect, criteria);
      //更新模板
      cv::Mat imageROI = imageHSV(rect);   
      framerecthsv = imageHSV(rect);
      calcHist(&imageROI, 2, channels, cv::Mat(), 
        dstHist, 1, &histSize, &histRange);
      normalize(dstHist, dstHist, 0.0, 1.0, cv::NORM_MINMAX);   //归一化  
      rectangle(frame, rect, cv::Scalar(255, 0, 0), 3);    //目标绘制    
      pt.push_back(cv::Point(rect.x + rect.width / 2, 
        rect.y + rect.height / 2));
      for (int i = 0; i < pt.size() - 1; i++)
      {
        cv::line(frame, pt[i], pt[i + 1], cv::Scalar(0, 255, 0), 2.5);
      }
    }
    cv::imshow("srcvideo", frame);
    cv::waitKey(50);
  }

  video.release();
  cv::waitKey(0);
  return 0;
}

//鼠标回调函数
void onMouse(int event, int x, int y, int flags, void * ustc)
{
  //鼠标左键按下
  if (event == CV_EVENT_LBUTTONDOWN)
  {
    leftButtonDownFlag = true; //更新按下标志位
    rectstartPoint = cv::Point(x, y); //设置矩形的开始点
    rectstopPoint = rectstartPoint;   //刚按下时结束点和开始点一样
  }
  //当鼠标按下并且开始移动时
  else if (event == CV_EVENT_MOUSEMOVE && leftButtonDownFlag)
  {
    framecopy = frame.clone();  //复制源图像
    rectstopPoint = cv::Point(x, y); //设置矩形的结束点
    if (rectstartPoint != rectstopPoint)
    {
      //当矩形的开始点和结束点不同后在复制的图像上绘制矩形
      cv::rectangle(framecopy, rectstartPoint, rectstopPoint,
        cv::Scalar(255, 255, 255));
    }
    cv::imshow("srcvideo", framecopy);
  }
  //当鼠标抬起时
  else if (event == CV_EVENT_LBUTTONUP)
  {
    leftButtonDownFlag = false;//按下鼠标标志位复位
    rect = cv::Rect(rectstartPoint, rectstopPoint);//设置选中后的矩形
    framerect = frame(rect); //通过矩形获取到选取后的图像
    cv::imshow("selectimg", framerect);//显示出来选择后的图像
    cv::cvtColor(framerect, framerecthsv, cv::COLOR_BGR2HSV);
    //直方图计算
    calcHist(&framerecthsv, 2, channels, cv::Mat(), dstHist, 1, &histSize, &histRange, true, false);
    //归一化显示
    normalize(dstHist, dstHist, 0, 255, CV_MINMAX);
  }

}