多台显示器上的 OpenCV 全屏窗口

Question

我有一个显示全屏窗口的 OpenCV 应用程序，通过:

cv::namedWindow("myWindow", CV_WINDOW_NORMAL)
cv::setWindowProperties("myWindow", CV_WND_PROP_FULLSCREEN, CV_WINDOW_FULLSCREEN)

它工作正常，但是当我有多个显示器时，它总是在第一个显示器上显示全屏窗口。有没有办法在第二台显示器上显示？我试过设置 X/Y 和宽度/高度，但一旦启用全屏，它们似乎就会被忽略。

Answer 1

编辑:

有时纯 OpenCV 代码无法在双显示器上显示全屏窗口。这是一个 Qt实现方式:

#include <QApplication>
#include <QDesktopWidget>
#include <QLabel>

#include <opencv2/highgui/highgui.hpp>

using namespace cv;

int main(int argc, char *argv[]) 
{
    QApplication app(argc, argv);
    QDesktopWidget dw;
    QLabel myLabel;

    // define dimension of the second display
    int width_second  = 2560;
    int height_second = 1440;

    // define OpenCV Mat
    Mat img = Mat(Size(width_second, height_second), CV_8UC1);

    // move the widget to the second display
    QRect screenres = QApplication::desktop()->screenGeometry(1);
    myLabel.move(QPoint(screenres.x(), screenres.y()));

    // set full screen
    myLabel.showFullScreen();

    // set Qimg
    QImage Qimg((unsigned char*)img.data, img.cols, img.rows, QImage::Format_Indexed8);

    // set Qlabel
    myLabel.setPixmap(QPixmap::fromImage(Qimg));

    // show the image via Qt
    myLabel.show();

    return app.exec();
}

不要忘记将 .pro 文件配置为:

TEMPLATE = app
QT += widgets
TARGET = main
LIBS += -L/usr/local/lib -lopencv_core -lopencv_highgui

# Input
SOURCES += main.cpp

然后在终端中将您的代码编译为:

qmake
make

---

原文:

这是可能的。

这是一个有效的演示代码，用于在第二个显示器上显示全屏图像。来自 How to display different windows in different monitors with OpenCV 的提示:

#include <opencv2/highgui/highgui.hpp>

using namespace cv;

int main ( int argc, char **argv )
{
    // define dimension of the main display
    int width_first  = 1920;
    int height_first = 1200;

    // define dimension of the second display
    int width_second  = 2560;
    int height_second = 1440;

    // move the window to the second display 
    // (assuming the two displays are top aligned)
    namedWindow("My Window", CV_WINDOW_NORMAL);
    moveWindow("My Window", width_first, height_first);
    setWindowProperty("My Window", CV_WND_PROP_FULLSCREEN, CV_WINDOW_FULLSCREEN);

    // create target image
    Mat img = Mat(Size(width_second, height_second), CV_8UC1);

    // show the image
    imshow("My Window", img);
    waitKey(0);

    return 0;
}