1、效果圖

2、camerathread.h

#ifndef CAMERATHREAD_H
#define CAMERATHREAD_H#include <QObject>
#include <QThread>
#include <QDebug>
#include <QImage>
#include <unistd.h>
#include <iostream>
#include <QDateTime>
#include <opencv2/opencv.hpp>
using namespace  std;
using namespace  cv;
class CameraThread :public QThread
{Q_OBJECT
public:static CameraThread *camerathread;static CameraThread *getInstance();void run();bool getIsRun() const;void setIsRun(bool value);int getFrame_width() const;int getFrame_height() const;void detecCarDaw(Mat &frame,CascadeClassifier &cascade,double scale);bool getIsStop() const;void setIsStop(bool value);bool getIsRecord() const;void setIsRecord(bool value);VideoWriter getWriter() const;bool getIsPersistent() const;void setIsPersistent(bool value);bool getIsRun_s() const;void setIsRun_s(bool value);
signals:void sendQImage(Mat frame);
private:CameraThread();CascadeClassifier cascade;//級聯分類器的過濾器VideoCapture cap;Mat frame;VideoWriter writer;//OpenCV視頻錄制類bool isRun;//控制線程是否運行int frame_width;int frame_height;int recordNum; //錄制幀率，設定為300幀bool isRun_s; //控制線程是否運行bool isStop; //控制線程結束bool isRecord; //控制線程是否開始錄制bool isPersistent;
};#endif // CAMERATHREAD_H

3、camerathread.cpp

#include "camerathread.h"CameraThread * CameraThread::camerathread =nullptr;
CameraThread * CameraThread::getInstance()
{if(CameraThread::camerathread ==nullptr){CameraThread::camerathread =new CameraThread ();}return CameraThread::camerathread;
}
CameraThread::CameraThread()
{this->isRun =true;cap.open(0);// 獲取攝像頭的寬度和高度this->frame_width = static_cast<int>(cap.get(CAP_PROP_FRAME_WIDTH));this->frame_height = static_cast<int>(cap.get(CAP_PROP_FRAME_HEIGHT));// 定義視頻編碼格式、幀率和畫面尺寸int fourcc = VideoWriter::fourcc('X', 'V', 'I', 'D');Size frameSize(frame_width, frame_height);this->isRun_s=false;this->isStop=false;this->isRecord=false;this->isPersistent=false;this->recordNum=0;}bool CameraThread::getIsStop() const
{return isStop;
}void CameraThread::setIsStop(bool value)
{isStop = value;
}bool CameraThread::getIsRecord() const
{return isRecord;
}void CameraThread::setIsRecord(bool value)
{isRecord = value;if(this->isRecord == false && writer.isOpened()){qDebug()<<"手動關閉"<<endl;writer.release();this->recordNum =0;}
}VideoWriter CameraThread::getWriter() const
{return writer;
}bool CameraThread::getIsPersistent() const
{return isPersistent;
}void CameraThread::setIsPersistent(bool value)
{isPersistent = value;
}bool CameraThread::getIsRun_s() const
{return isRun_s;
}void CameraThread::setIsRun_s(bool value)
{isRun_s = value;
}
void CameraThread::detecCarDaw(Mat &frame, CascadeClassifier &cascade, double scale)
{//灰度處理Mat gray;cvtColor(frame,gray,CV_BGR2GRAY);//將灰度圖縮小一半//cvRound（）用于四舍五入       CV_8UC1:單通道Mat smalling(cvRound(frame.rows/scale),cvRound(frame.cols/scale),CV_8UC1);//resize()改變大小      INTER_LINEAR 等比例縮小resize(gray,smalling,smalling.size(),0,0,INTER_LINEAR);//直方圖均衡化：利用直方圖函數將圖像黑白分明  （結果跟二值化類似）equalizeHist(smalling,smalling);//進行模型檢測vector<Rect>cars;cascade.detectMultiScale(smalling,cars,1.1,2,0|CV_HAAR_SCALE_IMAGE,Size(30,30));//繪制邊框vector<Rect>::const_iterator iter;//系統默認迭代器for(iter =cars.begin();iter!=cars.end();iter++){rectangle(frame,//原圖cvPoint(cvRound(iter->x*scale),cvRound(iter->y*scale)),//左上角坐標cvPoint(cvRound((iter->x+iter->width)*scale),cvRound((iter->y+iter->height)*scale)),//右下角坐標Scalar(0,255,0),//綠色2,//像素大小8//亮度);}
}int CameraThread::getFrame_height() const
{return frame_height;
}int CameraThread::getFrame_width() const
{return frame_width;
}bool CameraThread::getIsRun() const
{return isRun;
}void CameraThread::setIsRun(bool value)
{isRun = value;
}
void CameraThread::run()
{cascade.load("D:/OpenCV/cars.xml");//識別級聯分類器  車輛while(this->isRun ==true){if(cap.read(frame)){cvtColor(frame,frame,CV_BGR2RGB);detecCarDaw(frame,cascade,2);emit sendQImage(frame);if(this->isStop ==false)//控制線程結束{if(this->isRun_s == true)//控制線程是否運行{if(cap.read(frame)){if(this->isRecord==true){if(this->recordNum ==0){QDateTime current_date_time =QDateTime::currentDateTime();QString current_date =current_date_time.toString("yyyy-MM-dd-hh-mm-ss");//QString filename ="../data/"+current_date+".avi";QString filename ="D:/Qtsoft/videoDemo/data/"+current_date+".avi";qDebug()<<"filename="<<filename;writer.open(filename.toStdString().c_str(),CV_FOURCC('M','J','P','G'),30.0,Size(frame.cols,frame.rows),true);}if(!writer.isOpened()){qDebug()<<"錄制路徑失敗！！！"<<endl;}else{if(this->recordNum<300){//當前幀不等于總幀數，錄制300幀還沒有結束//qDebug()<<"錄制中..."<<endl;writer<<frame;this->recordNum++;}else{qDebug()<<"已經到300幀結束錄制";writer.release();this->recordNum =0;if(this->isPersistent==true){this->isRecord =true;}else if(this->isPersistent ==false){this->isRecord =false;}}}}cvtColor(frame,frame,CV_BGR2RGB);}msleep(10);}}}}}

4、mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>
#include "camerathread.h"
namespace Ui {
class MainWindow;
}class MainWindow : public QMainWindow
{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = nullptr);~MainWindow();void paintEvent(QPaintEvent * Eevent);
private:Ui::MainWindow *ui;CameraThread *ct;
//    VideoThread *vt;QImage image;Mat frame;
private slots:void isChecked(Mat frame);void on_pushButton_clicked();void on_checkBox_clicked(bool checked);
};#endif // MAINWINDOW_H

5、mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow)
{ui->setupUi(this);this->ct =CameraThread::getInstance();connect(this->ct,SIGNAL(sendQImage(Mat)),this,SLOT(isChecked(Mat)),Qt::BlockingQueuedConnection);this->ct->start();
//    this->vt =new VideoThread(0);
//    this->vt->start();waitKey(40);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::paintEvent(QPaintEvent *Eevent)
{ui->label->setPixmap(QPixmap::fromImage(this->image));QImage q_image = QImage(frame.data,frame.cols,frame.rows,QImage::Format_RGB888);ui->label->setPixmap(QPixmap::fromImage(q_image));ui->label->setScaledContents(true);
}void MainWindow::isChecked(Mat frame)
{this->image =QImage(frame.data,frame.cols,frame.rows,QImage::Format_RGB888);this->image = this->image.scaled(ui->label->width(),ui->label->height());//以UI中的界面大小進行等比例縮放this->frame = frame.clone();this->update();
}void MainWindow::on_pushButton_clicked()
{if(this->ct->getWriter().isOpened()){qDebug()<<"已經有錄制項目:請先結束錄制，再操作";return;}this->ct->setIsRun_s(true);this->ct->setIsRecord(true);}void MainWindow::on_checkBox_clicked(bool checked)
{if(checked==true){//qDebug()<<"true";this->ct->setIsRecord(true);this->ct->setIsPersistent(true);}else if(checked==false){//qDebug()<<"false";this->ct->setIsPersistent(false);}
}

6、main.cpp

#include "mainwindow.h"
#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}