Qt在单独的线程钟渲染yuv的例子-QT开发中文网

以下是一个简单的例子，展示了如何在单独的线程中渲染YUV图像并将其显示到GUI界面上：

main.cpp

#include <QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QThread>
#include <QImage>

class YuvRenderer : public QObject
{
    Q_OBJECT

public:
    void renderYuv(const uchar *yData, const uchar *uData, const uchar *vData,
                   int width, int height);

signals:
    void yuvRendered(QImage image);
};

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void onNewFrameReceived(const uchar *yData, const uchar *uData,
                            const uchar *vData, int width, int height);
    void onYuvRendered(QImage image);

private:
    Ui::MainWindow *ui;
    QThread thread;
    YuvRenderer renderer;
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    // Move the renderer object to a separate thread and start it.
    renderer.moveToThread(&thread);
    connect(&thread, &QThread::finished, &renderer, &QObject::deleteLater);
//     connect(&renderer, &YuvRenderer::yuvRendered, this, &MainWindow::onYuvRendered);
    thread.start();
}

MainWindow::~MainWindow()
{
    thread.quit();
    thread.wait();
    delete ui;
}

void MainWindow::onNewFrameReceived(const uchar *yData, const uchar *uData,
                                    const uchar *vData, int width, int height)
{
    QMetaObject::invokeMethod(&renderer, "renderYuv", Qt::QueuedConnection,
                              Q_ARG(const uchar*, yData),
                              Q_ARG(const uchar*, uData),
                              Q_ARG(const uchar*, vData),
                              Q_ARG(int, width),
                              Q_ARG(int, height));
}

void MainWindow::onYuvRendered(QImage image)
{
    ui->label->setPixmap(QPixmap::fromImage(image));
}

void YuvRenderer::renderYuv(const uchar *yData, const uchar *uData,
                            const uchar *vData, int width, int height)
{
    // Convert YUV to RGB and create a QImage object.
    QImage image(width, height, QImage::Format_RGB888);
    for (int i = 0; i < height; ++i) {
        for (int j = 0; j < width; ++j) {
            // Get the YUV values of the current pixel.
            int y = yData[i*width + j];
            int u = uData[(i/2)*(width/2) + (j/2)];
            int v = vData[(i/2)*(width/2) + (j/2)];

            // Convert YUV to RGB.
            int r = qBound(0, y + 1.4075*(v-128), 255);
            int g = qBound(0, y - 0.3455*(u-128) - 0.7169*(v-128), 255);
            int b = qBound(0, y + 1.7790*(u-128), 255);

            // Set the RGB values of the current pixel in the QImage.
            image.setPixel(j, i, qRgb(r, g, b));
        }
    }

    // Emit the yuvRendered signal with the resulting image.
    emit yuvRendered(image);
}

其中，MainWindow类是GUI界面的主窗口，它创建了一个YuvRenderer对象，并将其移动到一个单独的QThread线程中。当新的一帧YUV图像数据到达时，MainWindow类会调用YuvRenderer对象的renderYuv方法，在该方法中将YUV图像转换为RGB格式并创建QImage对象，最后通过信号yuvRendered将渲染结果发送回主线程进行显示。

注意：这里省略了对于输入参数的检查和异常处理等细节。在实际应用中需要根据具体情况进行处理。