界面主体

显示图像通过定时器定时调用信号槽里的更新函数实现

编写信号槽函数前需要先编译，这样才能更新界面的.h文件

具体实现

qtcameratest01.h修改如下：

#pragma once#include 
    
     #include "ui_qtcameratest01.h"#include 
     
      #include 
      
       #include 
       
         // for camerausing namespace cv;class qtcameratest01 : public QMainWindow{    Q_OBJECTpublic:    qtcameratest01(QWidget *parent = Q_NULLPTR);private:    Ui::qtcameratest01Class ui;    QTimer *timer;    Mat frame;    QImage image;    VideoCapture cap1;    private slots:    void opencam();    void nextFrame();    void closeCamara();    void camshot();};static QImage Mat2QImage(Mat& image);

qtcameratest01.cpp文件修改如下：

#include "qtcameratest01.h"#include 
    
     #include 
     
      #include 
      
       #include 
       
        #include 
        
          // for camera#include 
         
          using namespace cv;qtcameratest01::qtcameratest01(QWidget *parent) : QMainWindow(parent){ // 初始化 timer = new QTimer(this); timer->stop(); ui.setupUi(this); connect(ui.OpenCamBtn, SIGNAL(clicked()), this, SLOT(opencam())); connect(timer, SIGNAL(timeout()), this, SLOT(nextFrame())); connect(ui.CloseCamBtn, SIGNAL(clicked()), this, SLOT(closeCamara())); connect(ui.CamshotBtn, SIGNAL(clicked()), this, SLOT(camshot()));}void qtcameratest01::opencam(){ if (cap1.isOpened()) cap1.release(); double rate = cap1.get(CV_CAP_PROP_FPS); try { cap1.open(0); cap1 >> frame; if (!frame.empty()) { timer->setInterval(rate); timer->start(); } } catch (const std::exception&) { QMessageBox::critical(NULL, "ERROR", "打开失败",QMessageBox::Close); }}static QImage Mat2QImage(Mat& image){ QImage img; if (image.channels() == 3) { cvtColor(image, image, CV_BGR2RGB); img = QImage((const unsigned char *)(image.data), image.cols, image.rows, image.cols*image.channels(), QImage::Format_RGB888); } else if (image.channels() == 1) { img = QImage((const unsigned char *)(image.data), image.cols, image.rows, image.cols*image.channels(), QImage::Format_ARGB32); } else { img = QImage((const unsigned char *)(image.data), image.cols, image.rows, image.cols*image.channels(), QImage::Format_RGB888); } return img;}void qtcameratest01::nextFrame(){ cap1 >> frame; if (!frame.empty()) { image = Mat2QImage(frame); QImage* imgScaled = new QImage; QImage* imgc = ℑ *imgScaled = imgc->scaled(ui.campicreal->width(), ui.campicreal->height(), Qt::KeepAspectRatio); ui.campicreal->setPixmap(QPixmap::fromImage(*imgScaled)); }}void qtcameratest01::closeCamara(){ timer->stop();//停止读取数据。 cap1.release();//释放内存； }void qtcameratest01::camshot(){ QImage* imgScaled = new QImage; QImage* imgc = ℑ *imgScaled = imgc->scaled(ui.campicreal->width(), ui.campicreal->height(), Qt::KeepAspectRatio); ui.campicshot->setPixmap(QPixmap::fromImage(*imgScaled));}