基于opencv的简单视频处理类示例

#include "opencv2/opencv.hpp"
using namespace std;
using namespace cv;

class VideoProcessor
{
private:
VideoCapture caputure;
//图像处理函数指针
void (*process)(Mat &,Mat &);
bool callIt;
string WindowNameInput;
string WindowNameOutput;
//延时
int delay;
long fnumber;
//第frameToStop停止
long frameToStop;
//暂停标志
bool stop;

public:
VideoProcessor() : callIt(true),delay(0),fnumber(0),stop(false),frameToStop(-1){}

//设置图像处理函数
void setFrameProcess(void (*process)(Mat &,Mat &)){
this->process = process;
}

//打开视频
bool setInput(string filename){
fnumber = 0;
//若已打开，释放重新打开
caputure.release ();
return caputure.open (filename);
}

//设置输入视频播放窗口
void displayInput(string wn){
WindowNameInput = wn;
namedWindow (WindowNameInput);
}

//设置输出视频播放窗口
void displayOutput(string wn){
WindowNameOutput = wn;
namedWindow (WindowNameOutput);
}

//销毁窗口
void dontDisplay(){
destroyWindow (WindowNameInput);
destroyWindow (WindowNameOutput);
WindowNameInput.clear ();
WindowNameOutput.clear ();
}

//启动
void run()
{
Mat frame;
Mat output;

if(!isOpened())
return;

stop = false;
while(!isStopped())
{
//读取下一帧
if(!readNextFrame(frame))
break;
if(WindowNameInput.length ()!=0)
imshow (WindowNameInput,frame);
//处理该帧
if(callIt){
process(frame,output);
}
else{
output = frame;
}
if(WindowNameOutput.length ()!=0)
imshow (WindowNameOutput,output);
//按键暂停，继续按键继续
if(delay>=0&&waitKey (delay)>=0)
waitKey(0);
//到达指定暂停键，退出
if(frameToStop>=0&&getFrameNumber()==frameToStop)
stopIt();
}
}

//暂停键置位
void stopIt(){
stop = true;
}
//查询暂停标志位
bool isStopped(){
return stop;
}
//返回视频打开标志
bool isOpened(){
return  caputure.isOpened ();
}
//设置延时
void setDelay(int d){
delay = d;
}
//读取下一帧
bool readNextFrame(Mat &frame){
return caputure.read (frame);
}

void CallProcess(){
callIt = true;
}
void  dontCallProcess(){
callIt = false;
}

//设置停止帧
void stopAtFrameNo(long frame){
frameToStop = frame;
}
// 获得当前帧的位置
long getFrameNumber(){
long fnumber = static_cast<long>(caputure.get ((CV_CAP_PROP_POS_FRAMES)));
return fnumber;
}
//获取帧率
double getFrameRate(){
return caputure.get(CV_CAP_PROP_FPS);
}
};

//帧处理函数：canny边缘检测
static void canny(cv::Mat& img, cv::Mat& out) {
//灰度变换
if (img.channels()==3)
cvtColor(img,out,CV_BGR2GRAY);
// canny算子求边缘
Canny(out,out,100,200);
//颜色反转，看起来更舒服些
threshold(out,out,128,255,cv::THRESH_BINARY_INV);
}

int main(int argc, char *argv[])
{
VideoProcessor processor;
//打开输入视频
processor.setInput ("MAH00054.MP4");
processor.displayInput ("Current Frame");
processor.displayOutput ("Output Frame");
//设置每一帧的延时
processor.setDelay (1000./processor.getFrameRate ());
//设置帧处理函数，可以任意
processor.setFrameProcess (canny );
processor.run ();
return 0;
}