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A camera problem.

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  • JonBJ JonB

    @jenya7
    What is "not physically allocated", and why do you get an exception on what?

    There is a basic example at https://doc.qt.io/qt-5/qcameraviewfinder.html

    camera = new QCamera;
    
    viewfinder = new QCameraViewfinder();
    viewfinder->show();
    
    camera->setViewfinder(viewfinder);
    
    imageCapture = new QCameraImageCapture(camera);
    
    camera->setCaptureMode(QCamera::CaptureStillImage);
    camera->start();
    

    Did you test whether just this code might work for you?

    You also ought check those m_camera->isCaptureModeSupported(...) I mentioned, else you are whistling in the wind....

    J Offline
    J Offline
    jenya7
    wrote on last edited by jenya7
    #68

    @JonB
    viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget. in the original example viewfinder is tied to a StackedWidget panel.

    jsulmJ JonBJ 2 Replies Last reply
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    • jsulmJ jsulm

      @jenya7 said in A camera problem.:

      It's not physically allocated

      It is, see the first line in the constructor

      J Offline
      J Offline
      jenya7
      wrote on last edited by
      #69

      @jsulm said in A camera problem.:

      @jenya7 said in A camera problem.:

      It's not physically allocated

      It is, see the first line in the constructor

      It doesn't work

      jsulmJ 1 Reply Last reply
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      • J jenya7

        @JonB
        viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget. in the original example viewfinder is tied to a StackedWidget panel.

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #70

        @jenya7 said in A camera problem.:

        viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget.

        It's not "empty". And a widget does not have to be "tied" to another widget. If it is not and you call show() on it it will be shown in its own window, but it should not crash...

        https://forum.qt.io/topic/113070/qt-code-of-conduct

        J 1 Reply Last reply
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        • J jenya7

          @jsulm said in A camera problem.:

          @jenya7 said in A camera problem.:

          It's not physically allocated

          It is, see the first line in the constructor

          It doesn't work

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #71

          @jenya7 said in A camera problem.:

          It doesn't work

          What doesn't work? I'm sure that line works. Do you call show() after that line or before?

          https://forum.qt.io/topic/113070/qt-code-of-conduct

          1 Reply Last reply
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          • jsulmJ jsulm

            @jenya7 said in A camera problem.:

            viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget.

            It's not "empty". And a widget does not have to be "tied" to another widget. If it is not and you call show() on it it will be shown in its own window, but it should not crash...

            J Offline
            J Offline
            jenya7
            wrote on last edited by
            #72

            @jsulm said in A camera problem.:

            @jenya7 said in A camera problem.:

            viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget.

            It's not "empty". And a widget does not have to be "tied" to another widget. If it is not and you call show() on it it will be shown in its own window, but it should not crash...

            I see. I'll try to understand what causes the crash.

            1 Reply Last reply
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            • J jenya7

              @JonB
              viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget. in the original example viewfinder is tied to a StackedWidget panel.

              JonBJ Online
              JonBJ Online
              JonB
              wrote on last edited by JonB
              #73

              @jenya7 said in A camera problem.:

              viewfinder = new QCameraViewfinder(); is an empty object, not tied to any widget

              QCameraViewfinder is a QWidget, so don't know what this means. In your case you may need to give it a parent or add it somewhere. I have suggested code you might try before turning to your own code....

              1 Reply Last reply
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              • JonBJ JonB

                @jenya7
                What is "not physically allocated", and why do you get an exception on what?

                There is a basic example at https://doc.qt.io/qt-5/qcameraviewfinder.html

                camera = new QCamera;
                
                viewfinder = new QCameraViewfinder();
                viewfinder->show();
                
                camera->setViewfinder(viewfinder);
                
                imageCapture = new QCameraImageCapture(camera);
                
                camera->setCaptureMode(QCamera::CaptureStillImage);
                camera->start();
                

                Did you test whether just this code might work for you?

                You also ought check those m_camera->isCaptureModeSupported(...) I mentioned, else you are whistling in the wind....

                J Offline
                J Offline
                jenya7
                wrote on last edited by jenya7
                #74

                @JonB said in A camera problem.:

                @jenya7
                What is "not physically allocated", and why do you get an exception on what?

                There is a basic example at https://doc.qt.io/qt-5/qcameraviewfinder.html
                Did you test whether just this code might work for you?

                You also ought check those m_camera->isCaptureModeSupported(...) I mentioned, else you are whistling in the wind....

                bool supported = m_camera->isCaptureModeSupported(QCamera::CaptureStillImage);
                

                Yes. It's supported.
                I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.
                Is it normal?

                jsulmJ JonBJ 2 Replies Last reply
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                • J jenya7

                  @JonB said in A camera problem.:

                  @jenya7
                  What is "not physically allocated", and why do you get an exception on what?

                  There is a basic example at https://doc.qt.io/qt-5/qcameraviewfinder.html
                  Did you test whether just this code might work for you?

                  You also ought check those m_camera->isCaptureModeSupported(...) I mentioned, else you are whistling in the wind....

                  bool supported = m_camera->isCaptureModeSupported(QCamera::CaptureStillImage);
                  

                  Yes. It's supported.
                  I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.
                  Is it normal?

                  jsulmJ Offline
                  jsulmJ Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on last edited by
                  #75

                  @jenya7 said in A camera problem.:

                  I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                  Where do you see it and where do you create camera object? Can you please post relevant code?

                  https://forum.qt.io/topic/113070/qt-code-of-conduct

                  J 1 Reply Last reply
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                  • J jenya7

                    @JonB said in A camera problem.:

                    @jenya7
                    What is "not physically allocated", and why do you get an exception on what?

                    There is a basic example at https://doc.qt.io/qt-5/qcameraviewfinder.html
                    Did you test whether just this code might work for you?

                    You also ought check those m_camera->isCaptureModeSupported(...) I mentioned, else you are whistling in the wind....

                    bool supported = m_camera->isCaptureModeSupported(QCamera::CaptureStillImage);
                    

                    Yes. It's supported.
                    I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.
                    Is it normal?

                    JonBJ Online
                    JonBJ Online
                    JonB
                    wrote on last edited by JonB
                    #76

                    @jenya7
                    OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

                    J 1 Reply Last reply
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                    • JonBJ JonB

                      @jenya7
                      OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

                      J Offline
                      J Offline
                      jenya7
                      wrote on last edited by
                      #77

                      @JonB said in A camera problem.:

                      @jenya7
                      OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

                      It runs on Windows machine. Have to arrange some camera....

                      JonBJ 1 Reply Last reply
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                      • J jenya7

                        @JonB said in A camera problem.:

                        @jenya7
                        OK, but why not try the example from the docs, in a standalone test program? Not going to say it again.....

                        It runs on Windows machine. Have to arrange some camera....

                        JonBJ Online
                        JonBJ Online
                        JonB
                        wrote on last edited by
                        #78

                        @jenya7
                        What runs on Windows machine? It's just sample code, does it not run on whatever platform you are on? You may know better than I, I'll keep quiet now.

                        1 Reply Last reply
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                        • jsulmJ jsulm

                          @jenya7 said in A camera problem.:

                          I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                          Where do you see it and where do you create camera object? Can you please post relevant code?

                          J Offline
                          J Offline
                          jenya7
                          wrote on last edited by
                          #79

                          @jsulm said in A camera problem.:

                          @jenya7 said in A camera problem.:

                          I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                          Where do you see it and where do you create camera object? Can you please post relevant code?

                          I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.
                          This way it works without errors

                          QCameraViewfinder *v_finder;
                          
                          MainWindow::MainWindow(QWidget *parent) :
                              QMainWindow(parent),
                              ui(new Ui::MainWindow)
                          {
                              v_finder = new QCameraViewfinder(this);
                              v_finder->show();
                          
                              ui->setupUi(this);
                              ui->textEditTerminalTx->installEventFilter(this);
                          }
                          
                          void Camera::setCamera(const QCameraInfo &cameraInfo)
                          {
                                 //........................
                          
                               m_camera->setViewfinder(v_finder);
                          
                                //............................
                          }
                          
                          

                          Is it OK?

                          JonBJ 1 Reply Last reply
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                          • J jenya7

                            @jsulm said in A camera problem.:

                            @jenya7 said in A camera problem.:

                            I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                            Where do you see it and where do you create camera object? Can you please post relevant code?

                            I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.
                            This way it works without errors

                            QCameraViewfinder *v_finder;
                            
                            MainWindow::MainWindow(QWidget *parent) :
                                QMainWindow(parent),
                                ui(new Ui::MainWindow)
                            {
                                v_finder = new QCameraViewfinder(this);
                                v_finder->show();
                            
                                ui->setupUi(this);
                                ui->textEditTerminalTx->installEventFilter(this);
                            }
                            
                            void Camera::setCamera(const QCameraInfo &cameraInfo)
                            {
                                   //........................
                            
                                 m_camera->setViewfinder(v_finder);
                            
                                  //............................
                            }
                            
                            

                            Is it OK?

                            JonBJ Online
                            JonBJ Online
                            JonB
                            wrote on last edited by JonB
                            #80

                            @jenya7 said in A camera problem.:

                            I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

                            And what was the result?!

                            I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                            At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

                            J 1 Reply Last reply
                            1
                            • JonBJ JonB

                              @jenya7 said in A camera problem.:

                              I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

                              And what was the result?!

                              I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                              At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

                              J Offline
                              J Offline
                              jenya7
                              wrote on last edited by
                              #81

                              @JonB said in A camera problem.:

                              @jenya7 said in A camera problem.:

                              I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

                              And what was the result?!

                              I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                              At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

                              m_camera->setViewfinder(v_finder) is executed first

                              JonBJ 1 Reply Last reply
                              0
                              • J jenya7

                                @JonB said in A camera problem.:

                                @jenya7 said in A camera problem.:

                                I put a break point in the MainWindow constructor and Camera constructor and see which hits the first.

                                And what was the result?!

                                I see the Camera object is created before MainWindow::MainWindow(QWidget *parent) constructor.

                                At the time your Camera::setCamera() is called, has v_finder = new QCameraViewfinder(this); been executed yet? If not then v_finder in m_camera->setViewfinder(v_finder) will be nullptr....

                                m_camera->setViewfinder(v_finder) is executed first

                                JonBJ Online
                                JonBJ Online
                                JonB
                                wrote on last edited by
                                #82

                                @jenya7
                                Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

                                J 2 Replies Last reply
                                1
                                • JonBJ JonB

                                  @jenya7
                                  Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

                                  J Offline
                                  J Offline
                                  jenya7
                                  wrote on last edited by
                                  #83

                                  @JonB said in A camera problem.:

                                  @jenya7
                                  Then obviously it is not the right place to put m_camera->setViewfinder(v_finder);.... You cannot execute that line until both m_camera & v_finder have been initialized, so move it somewhere suitable.

                                  I'll try

                                  1 Reply Last reply
                                  0
                                  • M Offline
                                    M Offline
                                    mchinand
                                    wrote on last edited by
                                    #84

                                    It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

                                    J 1 Reply Last reply
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                                    • M mchinand

                                      It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

                                      J Offline
                                      J Offline
                                      jenya7
                                      wrote on last edited by
                                      #85

                                      @mchinand said in A camera problem.:

                                      It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

                                      It's a widget based example. I removed all widget related stuff cause I don't have all these controls for camera operating in my app. I control the camera with commands I type in a terminal.

                                      jsulmJ 1 Reply Last reply
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                                      • J jenya7

                                        @mchinand said in A camera problem.:

                                        It seems your code is largely based on the Camera Example; is that correct? Does that example work for you unmodified?

                                        It's a widget based example. I removed all widget related stuff cause I don't have all these controls for camera operating in my app. I control the camera with commands I type in a terminal.

                                        jsulmJ Offline
                                        jsulmJ Offline
                                        jsulm
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #86

                                        @jenya7 Come on, the question is whether this example works with your camera or not! Can't you simply try that?

                                        https://forum.qt.io/topic/113070/qt-code-of-conduct

                                        J 1 Reply Last reply
                                        3
                                        • jsulmJ jsulm

                                          @jenya7 Come on, the question is whether this example works with your camera or not! Can't you simply try that?

                                          J Offline
                                          J Offline
                                          jenya7
                                          wrote on last edited by jenya7
                                          #87

                                          @jsulm said in A camera problem.:

                                          @jenya7 Come on, the question is whether this example works with your camera or not! Can't you simply try that?

                                          I'll try tomorrow. I have to get a camera.

                                          well...in the original example I press on Capture Photo and it stays inactive forever.

                                          J.HilkJ 1 Reply Last reply
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