Qt界面加载网络摄像头，并实时显示，两种更新界面的方法

Qt界面加载网络摄像头，并实时显示，两种更新界面的方法

1、Qt界面加载网络摄像头，并实时显示，根据头文件中的宏定义来区分使用哪种方式。①Qt信号槽更新界面，②c语言回调方式更新界面
2、使用OpenCV、RTSP打开摄像头
3、适合初学者
4、本人使用Qt5.10.0、vs2015、opencv3.4.3，必须在运行根目录添加opencv动态库或将此库添加环境变量
5、里面涉及到一些单例模式、类静态成员的用法，后期再整理，供大家共同成长

 

代码：

********************LoadCamera.pro********************

#-------------------------------------------------

#

# Project created by QtCreator 2020-04-07T08:48:03

#

#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = LoadCamera

TEMPLATE = app

# The following define makes your compiler emit warnings if you use

# any feature of Qt which has been marked as deprecated (the exact warnings

# depend on your compiler). Please consult the documentation of the

# deprecated API in order to know how to port your code away from it.

DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.

# In order to do so, uncomment the following line.

# You can also select to disable deprecated APIs only up to a certain version of Qt.

#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \

        main.cpp \

    cframe.cpp \

    CReadVideo.cpp

HEADERS += \

    cframe.h \

    CReadVideo.h

INCLUDEPATH += \

D:\Softwares\opencv3.4.3\build\include\

D:\Softwares\opencv3.4.3\build\include\opencv\

D:\Softwares\opencv3.4.3\build\include\opencv2\

win32:CONFIG(release, debug|release): LIBS += -LD:/Softwares/opencv3.4.3/build/x64/vc15/lib/ -lopencv_world343

else:win32:CONFIG(debug, debug|release): LIBS += -LD:/Softwares/opencv3.4.3/build/x64/vc15/lib/ -lopencv_world343d

********************main.cpp********************

#include "cframe.h"

#include 

int main(int argc, char *argv[])

{

    QApplication a(argc, argv);

    CFrame w;

    w.show();

    return a.exec();

}

********************cframe.h********************

#ifndef CFRAME_H

#define CFRAME_H

#include 

#include 

#include 

class CFrame : public QFrame

{

    Q_OBJECT

public:

    explicit CFrame(QWidget *parent = 0);

    ~CFrame();

#ifdef USE_CALLBACK_1

    static void updateQImage(QImage image);

#endif

protected:

    //窗体改变大小

    void resizeEvent(QResizeEvent* event) override;

protected slots:

#ifdef USE_SIGNAL_SLOT

    //接收摄像头数据

    void slotRecviveQImage(const QImage& image);

#endif

private:

    //摄像头显示在的QLabel控件

    QLabel *m_LabelCameraView;

    //读视频线程

    CReadVideo* m_ReadVideo;

#ifdef USE_CALLBACK_1

    //单例、静态、回调使用的指针

    static CFrame* m_This;

#endif

};

#endif // CFRAME_H

********************cframe.cpp********************

#include "cframe.h"

#include 

#ifdef USE_CALLBACK_1

CFrame *CFrame::m_This = nullptr;

#endif

CFrame::CFrame(QWidget *parent) :

    QFrame(parent)

{

    resize(960, 540);

    this->setMinimumWidth(192);

    this->setMinimumHeight(108);

#ifdef USE_CALLBACK_1

    m_This = this;

#endif

    m_LabelCameraView = new QLabel(this);

    m_LabelCameraView->setGeometry(0, 0, this->width(), this->height());

    //海康摄像头rtsp://admin:[email protected]/h264/ch1/main/av_stream       ch2是辅码流

    //大华摄像头rtsp://admin:[email protected]:554/cam/realmonitor?channel=1&subtype=0   subtype=1是辅码流

    m_ReadVideo = new CReadVideo(this);

    m_ReadVideo->setVideoAddress("rtsp://admin:[email protected]:554/cam/realmonitor?channel=1&subtype=0");

#ifdef USE_CALLBACK_1

    m_ReadVideo->setUpdateMainThreadQImage(&CFrame::updateQImage);

#endif

#ifdef USE_SIGNAL_SLOT

    connect(m_ReadVideo, SIGNAL(sendQImage(const QImage)), this, SLOT(slotRecviveQImage(const QImage)));

#endif

    m_ReadVideo->start();

}

CFrame::~CFrame()

{

    m_ReadVideo->stop();

    delete m_ReadVideo;

    m_ReadVideo = nullptr;

    delete m_LabelCameraView;

    m_LabelCameraView = nullptr;

}

#ifdef USE_CALLBACK_1

void CFrame::updateQImage(QImage image)

{

    if(m_This->isHidden())

        return;

    m_This->m_LabelCameraView->setPixmap(QPixmap::fromImage(image));

}

#endif

void CFrame::resizeEvent(QResizeEvent *event)

{

    Q_UNUSED(event);

    //界面大小修改，则显示窗口跟随改变

    m_LabelCameraView->setGeometry(0, 0, this->width(), this->height());

}

#ifdef USE_SIGNAL_SLOT

void CFrame::slotRecviveQImage(const QImage& image)

{

    if(this->isHidden())

        return;

    m_LabelCameraView->setPixmap(QPixmap::fromImage(image));

}

#endif

********************creadvideo.h********************

#ifndef CREADVIDEO_H

#define CREADVIDEO_H

#include 

#include 

#include 

#define USE_SIGNAL_SLOT     //Qt信号槽更新界面

//#define USE_CALLBACK_1      //c语言回调方式更新界面

//#define USE_CALLBACK_2      //c++std回调方式更新界面

#ifdef USE_CALLBACK_1

typedef void (*pUpdateMainThreadQImage)(QImage image);

#endif

class CReadVideo : public QThread

{

    Q_OBJECT

public:

    explicit CReadVideo(QObject *parent = nullptr);

    ~CReadVideo();

    void stop();

#ifdef USE_CALLBACK_1

    void setUpdateMainThreadQImage(void* ptr);

#endif

    //设置网络摄像头地址

    void setVideoAddress(const QString& str);

#ifdef USE_SIGNAL_SLOT

signals:

    void sendQImage(const QImage&);

#endif

protected:

    virtual void run();

private:

    bool stopped;

    cv::VideoCapture m_VideoCapture;

    //Mat数据

    cv::Mat m_MatRead, m_MatRGB;

    //网络摄像头地址

    QString m_sVideoAddress;

#ifdef USE_CALLBACK_1

    //全局回调函数指针，用于回调主线程，更新界面

    pUpdateMainThreadQImage m_UpdateMainThreadQImage;

#endif

};

#endif // CREADVIDEO_H

********************creadvideo.cpp********************

#include "CReadVideo.h"

#include 

CReadVideo::CReadVideo(QObject *parent) : QThread(parent)

{

    stopped = false;

    m_sVideoAddress = "";

#ifdef USE_CALLBACK_1

    m_UpdateMainThreadQImage = nullptr;

#endif

}

CReadVideo::~CReadVideo()

{

    stopped = true;

    if(this->isRunning())

    {

        this->stop();

        //等待1500毫秒，线程退出

        for(int i=0; i<300; ++i)

        {

            if(stopped == false)

                break;

            //qDebug()<<"wait stop"< 
  
            msleep(5);
 
  
        }
 
  
    }
 
  
}
 
  
 
 
  
void CReadVideo::stop()
 
  
{
 
  
    stopped = true;
 
  
}
 
  
 
 
  
#ifdef USE_CALLBACK_1
 
  
void CReadVideo::setUpdateMainThreadQImage(void *ptr)
 
  
{
 
  
    m_UpdateMainThreadQImage = static_cast(ptr);
 
  
}
 
  
#endif
 
  
 
 
  
void CReadVideo::setVideoAddress(const QString& str)
 
  
{
 
  
    m_sVideoAddress = str;
 
  
}
 
  
 
 
  
void CReadVideo::run()
 
  
{
 
  
    stopped = false;
 
  
 
 
  
    while(!stopped)
 
  
    {
 
  
        try{
 
  
            //打开摄像头
 
  
            if(!m_VideoCapture.open(m_sVideoAddress.toStdString()))
 
  
            {
 
  
                sleep(6);
 
  
                continue;
 
  
            }
 
  
 
 
  
            while(!stopped)
 
  
            {
 
  
                if(!stopped)
 
  
                {
 
  
                    //读取摄像头视频
 
  
                    if(m_VideoCapture.read(m_MatRead))
 
  
                    {
 
  
                        //OpenCV使用BGR，QImage使用RGB，通道转换
 
  
                        cv::cvtColor(m_MatRead, m_MatRGB, CV_BGR2RGB);
 
  
                        //cv::Mat转QImage
 
  
                        QImage image = QImage(m_MatRGB.data, m_MatRGB.cols, m_MatRGB.rows, QImage::Format_RGB888);
 
  
 
 
  
#ifdef USE_SIGNAL_SLOT
 
  
                        //发送转换完成的QImage信号
 
  
                        if(!stopped)
 
  
                            emit sendQImage(image);
 
  
#endif
 
  
 
 
  
#ifdef USE_CALLBACK_1
 
  
                        m_UpdateMainThreadQImage(image);
 
  
#endif
 
  
                    }
 
  
                    else
 
  
                    {
 
  
                        break;
 
  
                    }
 
  
                }
 
  
                else
 
  
                {
 
  
                    break;
 
  
                }
 
  
            }
 
  
        }
 
  
        catch(QString sException)
 
  
        {
 
  
            Q_UNUSED(sException);
 
  
            sleep(60);
 
  
            continue;
 
  
        }
 
  
    }
 
  
 
 
  
    //m_VideoCapture.release();
 
  
    stopped = false;
 
  
}
 
  
 
 
  
 
 
  
整体代码，请见我的资源https://download.csdn.net/download/u011093735/15117317