Hands-On GUI Programming with C++ and Qt5

Capturing a camera image to file

We have learned how to connect to our camera using Qt's multimedia module in the previous section. Now, we will try and capture a still image from the camera and save it into a JPEG file. It's actually very very simple with Qt.

First, open mainwindow.h and add the following variable:

private: 
   Ui::MainWindow *ui; 
   QCamera* camera; 
   QCameraViewfinder* viewfinder; 
   QCameraImageCapture* imageCapture; 
   bool connected; 

Then, right-click on the Capture button in mainwindow.ui and select Go to slot.... Then, select clicked() and press OK. Now, a new slot function will be created for you in mainwindow.cpp. Add the following code to capture an image from the camera:

void MainWindow::on_captureButton_clicked() { if (connected) ...