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2.qt5和opencv4.3.0实现打开摄像头并截屏拍照,源码再将灰度化,源码直方化,源码html爱心表白源码简单边缘检测,源码怎么写?
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{
inline static void qWait(int ms)
{
Q_ASSERT(QCoreApplication::instance());
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timer.start();
do {
QCoreApplication::processEvents(QEventLoop::AllEvents,源码蜘蛛池pro源码 ms);
QTest::qSleep();
} while (timer.elapsed() < ms);
}
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void QTest::qSleep(int ms)
{
QTEST_ASSERT(ms > 0);
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Sleep(uint(ms));
#else
struct timespec ts = { ms / , (ms % ) * * };
nanosleep(&ts, NULL);
#endif
}
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[cpp] view plain copy
/* /internal
helper function to do thread sleeps, since usleep()/nanosleep()
aren't reliable enough (in terms of behavior and availability)
*/
static void thread_sleep(struct timespec *ti)
{
pthread_mutex_t mtx;
pthread_cond_t cnd;
pthread_mutex_init(&mtx, 0);
pthread_cond_init(&cnd, 0);
pthread_mutex_lock(&mtx);
(void) pthread_cond_timedwait(&cnd, &mtx, ti);
pthread_mutex_unlock(&mtx);
pthread_cond_destroy(&cnd);
pthread_mutex_destroy(&mtx);
}
void QThread::sleep(unsigned long secs)
{
struct timeval tv;
gettimeofday(&tv, 0);
struct timespec ti;
ti.tv_sec = tv.tv_sec + secs;
ti.tv_nsec = (tv.tv_usec * );
thread_sleep(&ti);
}
qt5和opencv4.3.0实现打开摄像头并截屏拍照,再将灰度化,源码源码画cad图直方化,源码边缘检测,源码怎么写?
代码如下,源码觉得有帮助可以采纳下,源码后面有我在vscode的源码源代码,可以对照输入测试#include <QApplication>
#include <QMainWindow>
#include <QPushButton>
#include <QVBoxLayout>
#include <QLabel>
#include <QPixmap>
#include <QTimer>
#include <opencv2/opencv.hpp>
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = nullptr)
: QMainWindow(parent)
{
// 创建显示摄像头图像的源码标签
imageLabel = new QLabel(this);
imageLabel->setAlignment(Qt::AlignCenter);
// 创建按钮
QPushButton *captureButton = new QPushButton("拍照", this);
connect(captureButton, &QPushButton::clicked, this, &MainWindow::captureImage);
// 创建垂直布局并将标签和按钮添加到布局中
QVBoxLayout *layout = new QVBoxLayout;
layout->addWidget(imageLabel);
layout->addWidget(captureButton);
// 创建主窗口并设置布局
QWidget *centralWidget = new QWidget(this);
centralWidget->setLayout(layout);
setCentralWidget(centralWidget);
// 设置定时器,定时更新摄像头图像
QTimer *timer = new QTimer(this);
connect(timer,源码系统源码购买平台 &QTimer::timeout, this, &MainWindow::updateImage);
timer->start(); // 每毫秒更新一次图像
}
private slots:
void updateImage()
{
// 打开摄像头
cv::VideoCapture cap(0);
if (!cap.isOpened())
{
qDebug() << "无法打开摄像头!";
return;
}
// 读取摄像头图像
cv::Mat frame;
cap.read(frame);
cap.release();
// 将OpenCV图像转换为Qt图像,源码并显示在标签上
QImage qImage(frame.data,源码自动获取网页源码 frame.cols, frame.rows, frame.step, QImage::Format_BGR);
QPixmap pixmap = QPixmap::fromImage(qImage);
imageLabel->setPixmap(pixmap.scaled(imageLabel->size(), Qt::KeepAspectRatio));
}
void captureImage()
{
// 获取当前摄像头图像
cv::VideoCapture cap(0);
if (!cap.isOpened())
{
qDebug() << "无法打开摄像头!";
return;
}
cv::Mat frame;
cap.read(frame);
cap.release();
// 转换为灰度图像
cv::cvtColor(frame, frame, cv::COLOR_BGR2GRAY);
// 直方化
cv::equalizeHist(frame, frame);
// 边缘检测
cv::Canny(frame, frame, , );
// 保存图像
cv::imwrite("captured_image.jpg", frame);
qDebug() << "已保存为 captured_image.jpg";
}
private:
QLabel *imageLabel;
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();
}
#include "main.moc"
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