Qt调用摄像头（截取并保存图片）
Qt如何调用系统摄像设备进行显示、截图、录制？ QCamera：系统摄像设备（摄像头） QCameraViewfinder：摄像取景器部件 QCameraImageCapture：截图部件
capture按钮：用于截图（截图后在右上角显示）save按钮：用于保存截取后的图片（此处测试路径为：F:\a.jpg）exit按钮：退出界面
效果如下：


代码如下：
#include "test_capture.h"Dialog::Dialog(QWidget *parent) :QDialog(parent){this->resize(600, 400);
camera = new QCamera();view_finder = new QCameraViewfinder();camera_image_capture = new QCameraImageCapture(camera);capture_button = new QPushButton();save_button = new QPushButton();exit_button = new QPushButton(); display_label = new QLabel();
QHBoxLayout *main_layout = new QHBoxLayout();QVBoxLayout *v_layout = new QVBoxLayout();
display_label->setFixedSize(150, 150);display_label->setScaledContents(true);
v_layout->addWidget(display_label);v_layout->addStretch();v_layout->addWidget(capture_button);v_layout->addWidget(save_button);v_layout->addWidget(exit_button);
main_layout->addWidget(view_finder);main_layout->addLayout(v_layout);
connect(capture_button, &QPushButton::clicked, this, &Dialog::captureImage);connect(save_button, &QPushButton::clicked, this, &Dialog::saveImage);connect(exit_button, &QPushButton::clicked, this, &Dialog::close);connect(camera_image_capture, &QCameraImageCapture::imageCaptured, this, &Dialog::displayImage);
camera_image_capture->setCaptureDestination(QCameraImageCapture::CaptureToFile);camera->setCaptureMode(QCamera::CaptureStillImage);camera->setViewfinder(view_finder);camera->start(); //启动摄像头
this->setLayout(main_layout);this->translateLanguage();}
Dialog::~Dialog(){
}
void Dialog::translateLanguage(){this->setWindowTitle("testCapture");capture_button->setText(tr("capture"));save_button->setText(tr("save"));exit_button->setText(tr("exit"));}
void Dialog::displayImage(int id, QImage image){display_label->setPixmap(QPixmap::fromImage(image)); }
void Dialog::captureImage(){//截图camera_image_capture->capture(); }
void Dialog::saveImage(){const QPixmap *pixmap = display_label->pixmap();if(pixmap){pixmap->save("F:\\a.jpg");}}