Opencv实现视频播放与进度控制

#include "core/core.hpp" 
#include "highgui/highgui.hpp" 
#include "imgproc/imgproc.hpp" 
#include <iostream> 
 
using namespace cv; 
 
int main(int argc,char *argv[]) 
{ 
  VideoCapture videoFriends(argv[1]); 
  VideoCapture videoPhone(argv[2]); 
  double fpsFriends=videoFriends.get(CV_CAP_PROP_FPS); 
  double fpsPhone=videoFriends.get(CV_CAP_PROP_FPS); 
  std::cout<<"FPS of Friends is： "<<fpsFriends<<std::endl; 
  std::cout<<"FPS of MyPhone is： "<<fpsPhone<<std::endl; 
  system("pause"); 
  return 0; 
} 

int createTrackbar(const string& trackbarname, const string& winname, 
               int* value, int count, 
               TrackbarCallback onChange = 0, 
               void* userdata = 0); 

#include "core/core.hpp" 
#include "highgui/highgui.hpp" 
#include "imgproc/imgproc.hpp" 
#include <iostream> 
 
using namespace cv; 
 
Mat image;  //读入视频帧的Mat 
char* windowName="Video Control"; //播放窗口名称 
char* trackBarName="播放进度";  //trackbar控制条名称 
double totalFrame=1.0;   //视频总帧数 
double currentFrame=1.0;  //当前播放帧 
int trackbarValue=1;  //trackbar控制量 
int trackbarMax=255;  //trackbar控制条最大值 
double frameRate=1.0; //视频帧率 
VideoCapture video;  //声明视频对象 
double controlRate=0.1; 
 
//控制条回调函数 
void TrackBarFunc(int ,void(*)); 
int main(int argc,char *argv[]) 
{ 
  //打开视频文件 
  video.open(argv[1]); 
  if(!video.isOpened()) 
  { 
    std::cout<<"Failed to open video"<<std::endl; 
  } 
  totalFrame=video.get(CV_CAP_PROP_FRAME_COUNT); //获取总帧数 
  frameRate=video.get(CV_CAP_PROP_FPS);  //获取帧率 
  double pauseTime=1000/frameRate; // 由帧率计算两幅图像间隔时间 
  namedWindow(windowName); 
  //在图像窗口上创建控制条 
  createTrackbar(trackBarName,windowName,&trackbarValue,trackbarMax,TrackBarFunc); 
  TrackBarFunc(0,0); 
  while (true) 
  { 
    video.read(image); 
    resize(image,image,Size(500,400)); //调整图像大小，视频在我的显示器上显示不全 
    imshow(windowName,image); //显示图像 
    waitKey(pauseTime);  //图像间隔 
    controlRate++;   
    if(controlRate>totalFrame) //播放完成退出 
    { 
      break; 
    } 
 
  } 
  video.release(); //释放视频，C++中不写也无碍，可以自动释放 
  waitKey(); 
  return 0; 
} 
void TrackBarFunc(int ,void(*)) 
{ 
  controlRate=(double)trackbarValue/trackbarMax*totalFrame; //trackbar控制条对视频播放进度的控制 
  video.set(CV_CAP_PROP_POS_FRAMES,controlRate);  //设置当前播放帧 
}

controlRate=(double)trackbarValue/trackbarMax*totalFrame; 
//trackbar控制条对视频播放进度的控制 

video.set(CV_CAP_PROP_POS_FRAMES,controlRate);  //设置当前播放帧