效果图提前展示，想试试再往下看：
在网上找了很久QT的摄像头打开方式，成功了，但是捕获照片一直不成功，我不知道是不是qt6版本的原因：这个多媒体窗口我安装没有效果
QT += multimediawidgets
之前使用过python的opencv，于是想到可以使用opencv来显示摄像头以及捕获照片。环境配置以及安装参考底下这个老哥的，这老哥真的帅，太强了：
安装连接：https://www.cnblogs.com/ybqjymy/p/18070391
完成之后，在打开qt create6，我是6.6版本，其他版本不知道可不可以。
设置ui界面，如图所示：
这个是pro文件
//opencv_test.proQT += core gui multimediagreaterThan(QT_MAJOR_VERSION, 4): QT += widgetsCONFIG += c++11# The following define makes your compiler emit warnings if you use# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0SOURCES += \main.cpp \mainwindow.cppHEADERS += \mainwindow.hFORMS += \mainwindow.ui//很重要：主要添加这两行，指定头文件路径和库路径
INCLUDEPATH += D:\opencv\opencv\opencv-build\install\include
LIBS += D:\opencv\opencv\opencv-build\install\x64\mingw\lib\libopencv_*.a# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target
这个是mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>
#include <QLabel>
#include <QTimer>
#include <opencv2/opencv.hpp>QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACEclass MainWindow : public QMainWindow
{Q_OBJECTpublic:MainWindow(QWidget *parent = nullptr);~MainWindow();private slots:void updateCameraFrame();void on_pushButton_clicked();private:Ui::MainWindow *ui;QLabel *cameraLabel;QLabel *cameraLabel2;QTimer *timer;cv::VideoCapture cap;QImage MatToQImage(const cv::Mat &mat);
};#endif // MAINWINDOW_H
这个是main.cpp
#include "mainwindow.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}这个是mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <opencv2/opencv.hpp>
#include <QDebug>
#include <QMessageBox>
#include <QDateTime>
#include <QDir>using namespace cv;MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow), cap(0) // 打开默认摄像头
{ui->setupUi(this);cameraLabel = ui->label;cameraLabel2 = ui->label_2;timer = new QTimer(this);connect(timer, &QTimer::timeout, this, &MainWindow::updateCameraFrame);timer->start(30); // 更新间隔30msif (!cap.isOpened()) {qDebug() << "无法打开摄像头";QMessageBox::critical(this, "错误", "无法打开摄像头");}}MainWindow::~MainWindow()
{delete ui;cap.release();delete timer;
}void MainWindow::updateCameraFrame()
{Mat frame;cap >> frame;if (frame.empty()) {qDebug() << "无法读取数据";QMessageBox::critical(this, "错误", "无法从摄像头读取数据");return;}QImage img = MatToQImage(frame);cameraLabel->setPixmap(QPixmap::fromImage(img));
}QImage MainWindow::MatToQImage(const cv::Mat &mat)
{if (mat.type() == CV_8UC1) {QImage image(mat.cols, mat.rows, QImage::Format_Grayscale8);uchar *ptr = image.bits();for (int i = 0; i < mat.rows; ++i) {memcpy(ptr, mat.ptr(i), mat.cols);ptr += image.bytesPerLine();}return image;} else if (mat.type() == CV_8UC3) {const uchar *qImgBuf = (const uchar*)mat.data;QImage img(qImgBuf, mat.cols, mat.rows, mat.step, QImage::Format_RGB888);return img.rgbSwapped();} else {qDebug() << "cv::Mat image type not handled in switch:" << mat.type();return QImage();}
}void MainWindow::on_pushButton_clicked()
{Mat frame;cap >> frame;if (frame.empty()) {qDebug() << "无法读取数据";QMessageBox::critical(this, "错误", "无法从摄像头读取数据");return;}QImage img = MatToQImage(frame);cameraLabel2->setPixmap(QPixmap::fromImage(img));QString savePath = "D:/image/";QDir dir(savePath);if (!dir.exists()) {dir.mkpath(savePath);}QString fileName = QDateTime::currentDateTime().toString("yyyyMMdd_hhmmss") + ".jpg";QString filePath = savePath + fileName;bool isSaved = cv::imwrite(filePath.toStdString(), frame);if (isSaved) {QMessageBox::information(this, "图片保存", "图片已成功保存到：" + filePath);} else {QMessageBox::critical(this, "错误", "保存图片失败");}
}效果图展示：
