void MainWindow::on_actionSave_triggered()
{
    // Opens a saving browser for the user to choose where he wants to save the file and its name.
    QString fileName = QFileDialog::getSaveFileName(this, tr("Save Picture"), "", tr("Files (*.*)"));
    QPixmap picture = *ui->label->pixmap();

    // Checks if the user added an extension to the picture, if he didn't, the default saving is .jpg.
    if(!(fileName.contains(".png") || fileName.contains(".jpg") || fileName.contains(".bmp"))) fileName.append(".jpg");
    picture.save(fileName);
}