c++ qt opencv利用线程存储图像
时间: 2023-05-21 22:00:57 浏览: 124
可以使用Qt的QThread类来实现线程,利用OpenCV的VideoCapture类获取摄像头的图像,然后将图像存储到一个缓冲区中,最后在主线程中将缓冲区中的图像显示出来。以下是示例代码:
```c++
#include <QThread>
#include <QMutex>
#include <QImage>
#include <opencv2/opencv.hpp>
class CameraThread : public QThread
{
Q_OBJECT
public:
CameraThread(QObject *parent = nullptr);
~CameraThread();
void stop();
signals:
void imageReady(const QImage &image);
protected:
void run() override;
private:
QMutex m_mutex;
bool m_stopped;
};
CameraThread::CameraThread(QObject *parent)
: QThread(parent)
, m_stopped(false)
{
}
CameraThread::~CameraThread()
{
stop();
wait();
}
void CameraThread::stop()
{
m_mutex.lock();
m_stopped = true;
m_mutex.unlock();
}
void CameraThread::run()
{
cv::VideoCapture cap(0);
if (!cap.isOpened()) {
qDebug() << "Failed to open camera";
return;
}
while (true) {
m_mutex.lock();
if (m_stopped) {
m_mutex.unlock();
break;
}
m_mutex.unlock();
cv::Mat frame;
cap >> frame;
if (frame.empty()) {
qDebug() << "Failed to capture frame";
continue;
}
QImage image(frame.data, frame.cols, frame.rows, frame.step, QImage::Format_RGB888);
image = image.rgbSwapped();
emit imageReady(image);
}
}
```
在主线程中,可以将CameraThread的imageReady信号连接到一个槽函数中,将图像显示出来:
```c++
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = nullptr);
~MainWindow();
private slots:
void onImageReady(const QImage &image);
private:
Ui::MainWindow *ui;
CameraThread *m_cameraThread;
};
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
, m_cameraThread(new CameraThread(this))
{
ui->setupUi(this);
connect(m_cameraThread, &CameraThread::imageReady, this, &MainWindow::onImageReady);
m_cameraThread->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::onImageReady(const QImage &image)
{
ui->label->setPixmap(QPixmap::fromImage(image));
}
```
这样就可以利用线程存储图像并显示了。