需求：子執行緒程式採集影象，視窗執行緒實時顯示影象

平臺：VS2017+QT4.5

實現方法：

1建立繼承QObject的ImageContinuous類，實現連續採集影象

2主執行緒內建立ImageContinuous的物件指標，同時建立QThread類的物件指標

3子執行緒內建立槽函式，實現連續採集功能

4子執行緒內建立訊號，像主執行緒傳送訊號，訊號帶引數cv::Mat型；

5主執行緒建立訊號start，傳送start觸發子執行緒的連續採集槽函式；

6連續採集槽函式每採集一張圖，向主執行緒傳送一次訊號，訊號包含影象內容

7主執行緒接收到子執行緒訊號，更新ui影象顯示

子執行緒類程式碼，標頭檔案

#pragma once
#include <qobject.h>
#include "MvcCamera.h"
class ImageContinuous :    public QObject
{
    Q_OBJECT
public:
    //explicit ImageContinuous(QObject *parent = 0) : QObject(parent) {}
    ImageContinuous();
    ~ImageContinuous();
public slots:
    void getImage(MvcCamera &m_camera);
signals:
    
 
void imageInfo(cv::Mat temp);
};

子執行緒類程式碼，原始檔

#include "ImageContinuous.h"
#include "QThread.h"
#include <QDebug>
ImageContinuous::ImageContinuous()
{
}

ImageContinuous::~ImageContinuous()
{
}

void ImageContinuous::getImage(MvcCamera &m_camera)
{
    //QTimer::singleShot();//此函式可用，後期研究

    while
 
 (true)
    {
        cv::Mat m_image = m_camera.CaptureOneImage();
        cv::Mat m_imageToShow_1;
        //原始解析度，2048*1536，縮小512*384
        cv::resize(m_image, m_imageToShow_1, cv::Size(m_image.cols / 4, m_image.rows / 4), 0, 0, CV_INTER_LINEAR);
        emit imageInfo(m_imageToShow_1);
        QThread::msleep(30);
        //qDebug() << "current threadID:" << QThread::currentThread() << endl;
    }
}

主執行緒內部分程式碼，類的例項定義

private:
    ImageContinuous *m_imageConti;
    QThread *m_realtimeImageThread;

槽函式定義

    void showRealTimeVideo(cv::Mat image);

啟動採圖的訊號定義

void startChildThread(MvcCamera &m_camera);

部分原始檔程式碼，槽訊號傳遞自定義型別引數時必須使用註冊的方式，一開始採用訊號的連線方式為Qt:DirectionConnect，程式碼可以編譯過去，但是引數傳遞不過去，並且會導致無法開啟子執行緒！！

//分配記憶體
    m_imageConti = new ImageContinuous;
    m_realtimeImageThread = new QThread;

    //自定義型別作為槽訊號的引數，需要先註冊
    qRegisterMetaType<cv::Mat>("cv::Mat");
    qRegisterMetaType<MvcCamera>("MvcCamera&");

    connect(m_realtimeImageThread, &QThread::finished, m_imageConti, &QObject::deleteLater);
    connect(m_realtimeImageThread, &QThread::finished, m_realtimeImageThread, &QObject::deleteLater);


    connect(this, &QtWeldingRobotControlSystem::startChildThread, m_imageConti, &ImageContinuous::getImage);
    connect(m_imageConti, &ImageContinuous::imageInfo, this, &QtWeldingRobotControlSystem::showRealTimeVideo);

    m_imageConti->moveToThread(m_realtimeImageThread);

    //啟動子執行緒
    m_realtimeImageThread->start();