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QCamera Problems!

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  • SGaistS SGaist

    You should check the QtMultimedia plugin with ldd to see if it finds the gstreamer libraries. It might be still using the 0.1 version.

    Hasan VaezH Offline
    Hasan VaezH Offline
    Hasan Vaez
    wrote on last edited by
    #6

    @SGaist said in QCamera Problems!:

    QtMultimedia

    0_1521769297493_Screen Shot 2018-03-23 at 6.10.17 AM.png

    1 Reply Last reply
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    • Hasan VaezH Hasan Vaez

      @SGaist said in QCamera Problems!:

      check the QtMultimedia plugin with ldd

      Thank you SGaist, there is no EXEC file in gstreamer plugin folder. With ldd we can just check exec dependency Libs.
      Would you please tell me how to check Lib dependency of Qt Plugins?

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #7

      @Hasan-Vaez said in QCamera Problems!:

      With ldd we can just check exec dependency Libs.

      This is wrong. ldd works with libs as well

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

      Hasan VaezH 1 Reply Last reply
      2
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #8

        You are mixing your distribution provided Qt with the one you installed through the online installer. They are two different versions of Qt hence my question about the libraries linked to your 5.10 version of the gstreamer plugin.

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        Hasan VaezH 2 Replies Last reply
        1
        • jsulmJ jsulm

          @Hasan-Vaez said in QCamera Problems!:

          With ldd we can just check exec dependency Libs.

          This is wrong. ldd works with libs as well

          Hasan VaezH Offline
          Hasan VaezH Offline
          Hasan Vaez
          wrote on last edited by
          #9

          @jsulm I know. Where is lib (SO file) in Multimedia plugin?

          jsulmJ 1 Reply Last reply
          0
          • Hasan VaezH Hasan Vaez

            @jsulm I know. Where is lib (SO file) in Multimedia plugin?

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by
            #10

            @Hasan-Vaez For camera:

            ldd ~/Qt/5.10.0/gcc_64/plugins/mediaservice/libgstcamerabin.so 
            

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

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            • SGaistS SGaist

              You are mixing your distribution provided Qt with the one you installed through the online installer. They are two different versions of Qt hence my question about the libraries linked to your 5.10 version of the gstreamer plugin.

              Hasan VaezH Offline
              Hasan VaezH Offline
              Hasan Vaez
              wrote on last edited by
              #11

              @SGaist Thank you for your reply and trying to solve this maybe bug.
              I did not install GStreamer after installing QT.

              I try to setup a new Ubuntu 16.04LTS in VMWare machine + QT5.10.0 again and run the example of QCamera which is in part of the Qt package and see what happened.

              1 Reply Last reply
              0
              • SGaistS SGaist

                You are mixing your distribution provided Qt with the one you installed through the online installer. They are two different versions of Qt hence my question about the libraries linked to your 5.10 version of the gstreamer plugin.

                Hasan VaezH Offline
                Hasan VaezH Offline
                Hasan Vaez
                wrote on last edited by Hasan Vaez
                #12

                @SGaist said in QCamera Problems!:

                with

                I installed a new Ubuntu 14.04 LTS, Qt5.10.0 (Offline installer).
                Also installed some essential PKGs for running Camera: mesa-common-dev, libpulse-dev, libgl1-mesa-dev

                But problem is remained!!!

                Mr. Gsaist, did you tried? : https://doc.qt.io/qt-5.10/qtmultimedia-multimediawidgets-camera-example.html

                Would you please make a run the QCamera example from QT example folder.

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                • mranger90M Offline
                  mranger90M Offline
                  mranger90
                  wrote on last edited by
                  #13

                  If you are running from a VMware machine, you could have problems accessing the camera.
                  Make sure that the camera is not connected to the host.
                  See the "Player | Removable Devices | ..." menu option of VMware player.
                  Also, if its connect to the usb you may have to downgrade from usb3.0 to sub 2.0 or even usb 1.1 from the player settings menu.

                  Hasan VaezH 1 Reply Last reply
                  0
                  • mranger90M mranger90

                    If you are running from a VMware machine, you could have problems accessing the camera.
                    Make sure that the camera is not connected to the host.
                    See the "Player | Removable Devices | ..." menu option of VMware player.
                    Also, if its connect to the usb you may have to downgrade from usb3.0 to sub 2.0 or even usb 1.1 from the player settings menu.

                    Hasan VaezH Offline
                    Hasan VaezH Offline
                    Hasan Vaez
                    wrote on last edited by Hasan Vaez
                    #14

                    @mranger90
                    Thank you, but I think you do not read my full description in the top.
                    I tested it in another PC without VM.

                    1 Reply Last reply
                    0
                    • mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #15

                      @Hasan-Vaez said in QCamera Problems!:

                      Unable to query the parameter info: "Invalid argument"

                      Google that suggest something with the gstreamer. but im not 100% sure.

                      Anyway, i would test the camera in the same linux using some linux camera program to verify something can see it.
                      https://www.linuxlinks.com/webcam/

                      1 Reply Last reply
                      0
                      • Hasan VaezH Offline
                        Hasan VaezH Offline
                        Hasan Vaez
                        wrote on last edited by Hasan Vaez
                        #16

                        Just tell me, you do not having any problem with Camera with QT C++ in linux?

                        1 Reply Last reply
                        0
                        • mranger90M Offline
                          mranger90M Offline
                          mranger90
                          wrote on last edited by
                          #17

                          I've been able to use it many time with various Linuxi and through several Qt releases.
                          Are you able to use the camera outside of Qt, for example with the Cheese app ?

                          Hasan VaezH 2 Replies Last reply
                          0
                          • mranger90M mranger90

                            I've been able to use it many time with various Linuxi and through several Qt releases.
                            Are you able to use the camera outside of Qt, for example with the Cheese app ?

                            Hasan VaezH Offline
                            Hasan VaezH Offline
                            Hasan Vaez
                            wrote on last edited by Hasan Vaez
                            #18

                            @mranger90
                            Thank you for your reply.
                            Yes, I can use it outside of QT. I tested it with Cheese app in Ubuntu 16.04 LTS without any problem.
                            I also have not any problem in other OS like MAC and WINDOWS.

                            1 Reply Last reply
                            0
                            • mranger90M mranger90

                              I've been able to use it many time with various Linuxi and through several Qt releases.
                              Are you able to use the camera outside of Qt, for example with the Cheese app ?

                              Hasan VaezH Offline
                              Hasan VaezH Offline
                              Hasan Vaez
                              wrote on last edited by Hasan Vaez
                              #19

                              @mranger90
                              Please tell me what plugins did you install for qmultimedia in QT5?

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                              0
                              • mranger90M Offline
                                mranger90M Offline
                                mranger90
                                wrote on last edited by
                                #20

                                Unfortunately I don't have any of those systems in front of me now and won't until Monday.
                                Off the top of my head I'm pretty sure I've installed libgstreamerdev and maybe gstpluginsbase?
                                Not sure of the exact package names.

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                                0
                                • mranger90M Offline
                                  mranger90M Offline
                                  mranger90
                                  wrote on last edited by
                                  #21

                                  Ok, I just set up an Ubuntu 16.04 VM with VMWare on my pathetically underpowered home system which is running Win 10 as the native OS.
                                  Installed Qt 5.10.0.
                                  Have a Microsoft LifeCam HD-600 usb camera.
                                  VMWare is set up to use USB 1.1.
                                  Cheese can access and display the camera.
                                  To build the Examples/multimediaWidgets/camera project I had to install:
                                  libgl-mesa-dev
                                  mesa-common-dev
                                  libpulse-dev

                                  Other than a little fiddling with the camera parameters that's all I had to do to get it to work on a stock ubuntu 16.04 install.
                                  I'd have to dig out some of my other apps to test with, but it looks like this should work for you. If you can post a more complete set of your code I'd be happy to test it tomorrow.

                                  Hasan VaezH 1 Reply Last reply
                                  1
                                  • mranger90M mranger90

                                    Ok, I just set up an Ubuntu 16.04 VM with VMWare on my pathetically underpowered home system which is running Win 10 as the native OS.
                                    Installed Qt 5.10.0.
                                    Have a Microsoft LifeCam HD-600 usb camera.
                                    VMWare is set up to use USB 1.1.
                                    Cheese can access and display the camera.
                                    To build the Examples/multimediaWidgets/camera project I had to install:
                                    libgl-mesa-dev
                                    mesa-common-dev
                                    libpulse-dev

                                    Other than a little fiddling with the camera parameters that's all I had to do to get it to work on a stock ubuntu 16.04 install.
                                    I'd have to dig out some of my other apps to test with, but it looks like this should work for you. If you can post a more complete set of your code I'd be happy to test it tomorrow.

                                    Hasan VaezH Offline
                                    Hasan VaezH Offline
                                    Hasan Vaez
                                    wrote on last edited by Hasan Vaez
                                    #22

                                    @mranger90 said in QCamera Problems!:

                                    libpulse-dev

                                    Thank you arranger for your comments.
                                    I install another Ubuntu 16.04, Qt5.10.0 (along with 3 components: libgl1-mesa-dev mesa-common-dev libpulse-dev)
                                    Test the Camera example with VMWARE MAC CAM and also with LOGITEC CAM.

                                    The problem remained!

                                    My codes are:
                                    1- Camera example in QT folder
                                    2- The following simple codes:

                                    QCamera *Camera;
                                    QCameraImageCapture *ImageCapture;
                                    QCameraInfo *CameraInfo;

                                    void MainWindow::on_pushButton_clicked()
                                    {
                                    Camera = new QCamera;
                                    ImageCapture = new QCameraImageCapture(Camera);

                                    Camera->setViewfinder(ui->wCamera);
                                    ui->wCamera->setAspectRatioMode(Qt::KeepAspectRatioByExpanding);
                                    Camera->setCaptureMode(QCamera::CaptureViewfinder);
                                    Camera->start();
                                    }

                                    All things seems to be correct, there should be a small point which I don't know what is it??

                                    1 Reply Last reply
                                    0
                                    • mranger90M Offline
                                      mranger90M Offline
                                      mranger90
                                      wrote on last edited by
                                      #23

                                      ok, Heres the simplest code I could create that runs with my setup:
                                      Mainwindow.h

                                      #ifndef MAINWINDOW_H
                                      #define MAINWINDOW_H
                                      
                                      #include <QMainWindow>
                                      #include <QCamera>
                                      
                                      namespace Ui {
                                      class MainWindow;
                                      }
                                      
                                      class MainWindow : public QMainWindow
                                      {
                                          Q_OBJECT
                                      
                                      public:
                                          explicit MainWindow(QWidget *parent = 0);
                                          ~MainWindow();
                                      
                                      private slots:
                                          void on_actionStart_triggered();
                                      
                                      private:
                                          Ui::MainWindow *ui;
                                          QCamera *m_camera;
                                      };
                                      
                                      #endif // MAINWINDOW_H
                                      
                                      

                                      mainwindow.cpp

                                      #include "mainwindow.h"
                                      #include "ui_mainwindow.h"
                                      
                                      #include <QVideoWidget>
                                      #include <QCameraInfo>
                                      #include <QCameraViewfinderSettings>
                                      #include <QDebug>
                                      
                                      MainWindow::MainWindow(QWidget *parent) :
                                          QMainWindow(parent),
                                          ui(new Ui::MainWindow)
                                      {
                                          ui->setupUi(this);
                                          QVideoWidget *videoDisplay = new QVideoWidget;
                                          setCentralWidget(videoDisplay);
                                      
                                          // get a list of available cameras
                                          QList<QCameraInfo> cameras = QCameraInfo::availableCameras();
                                          // just pick the first
                                          if (cameras.size() > 0) {
                                              qDebug() << "creating camera from " << cameras.at(0).deviceName() << cameras.at(0).description();
                                              m_camera = new QCamera(cameras.at(0));
                                              if (m_camera) {
                                                  m_camera->setViewfinder(videoDisplay);
                                                  m_camera->setCaptureMode(QCamera::CaptureViewfinder);
                                                  QCameraViewfinderSettings settings = m_camera->viewfinderSettings();
                                                  // change resolution to 320x240
                                                  settings.setResolution(QSize(320,240));
                                                  m_camera->setViewfinderSettings(settings);
                                      
                                      
                                              }
                                          }
                                      }
                                      
                                      MainWindow::~MainWindow()
                                      {
                                          delete ui;
                                      }
                                      
                                      void MainWindow::on_actionStart_triggered()
                                      {
                                          if (m_camera) {
                                              m_camera->start();
                                          }
                                      }
                                      
                                      

                                      camtest.pro

                                      
                                      QT       += core gui multimedia multimediawidgets
                                      
                                      greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                                      
                                      TARGET = camtest
                                      TEMPLATE = app
                                      
                                      DEFINES += QT_DEPRECATED_WARNINGS
                                      SOURCES += \
                                              main.cpp \
                                              mainwindow.cpp
                                      
                                      HEADERS += \
                                              mainwindow.h
                                      
                                      FORMS += \
                                              mainwindow.ui
                                      
                                      

                                      Mainwindow is just a stock MainWindow with a menu item to start video capture.

                                      Let me know if this works.

                                      Hasan VaezH 1 Reply Last reply
                                      2
                                      • mranger90M mranger90

                                        ok, Heres the simplest code I could create that runs with my setup:
                                        Mainwindow.h

                                        #ifndef MAINWINDOW_H
                                        #define MAINWINDOW_H
                                        
                                        #include <QMainWindow>
                                        #include <QCamera>
                                        
                                        namespace Ui {
                                        class MainWindow;
                                        }
                                        
                                        class MainWindow : public QMainWindow
                                        {
                                            Q_OBJECT
                                        
                                        public:
                                            explicit MainWindow(QWidget *parent = 0);
                                            ~MainWindow();
                                        
                                        private slots:
                                            void on_actionStart_triggered();
                                        
                                        private:
                                            Ui::MainWindow *ui;
                                            QCamera *m_camera;
                                        };
                                        
                                        #endif // MAINWINDOW_H
                                        
                                        

                                        mainwindow.cpp

                                        #include "mainwindow.h"
                                        #include "ui_mainwindow.h"
                                        
                                        #include <QVideoWidget>
                                        #include <QCameraInfo>
                                        #include <QCameraViewfinderSettings>
                                        #include <QDebug>
                                        
                                        MainWindow::MainWindow(QWidget *parent) :
                                            QMainWindow(parent),
                                            ui(new Ui::MainWindow)
                                        {
                                            ui->setupUi(this);
                                            QVideoWidget *videoDisplay = new QVideoWidget;
                                            setCentralWidget(videoDisplay);
                                        
                                            // get a list of available cameras
                                            QList<QCameraInfo> cameras = QCameraInfo::availableCameras();
                                            // just pick the first
                                            if (cameras.size() > 0) {
                                                qDebug() << "creating camera from " << cameras.at(0).deviceName() << cameras.at(0).description();
                                                m_camera = new QCamera(cameras.at(0));
                                                if (m_camera) {
                                                    m_camera->setViewfinder(videoDisplay);
                                                    m_camera->setCaptureMode(QCamera::CaptureViewfinder);
                                                    QCameraViewfinderSettings settings = m_camera->viewfinderSettings();
                                                    // change resolution to 320x240
                                                    settings.setResolution(QSize(320,240));
                                                    m_camera->setViewfinderSettings(settings);
                                        
                                        
                                                }
                                            }
                                        }
                                        
                                        MainWindow::~MainWindow()
                                        {
                                            delete ui;
                                        }
                                        
                                        void MainWindow::on_actionStart_triggered()
                                        {
                                            if (m_camera) {
                                                m_camera->start();
                                            }
                                        }
                                        
                                        

                                        camtest.pro

                                        
                                        QT       += core gui multimedia multimediawidgets
                                        
                                        greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                                        
                                        TARGET = camtest
                                        TEMPLATE = app
                                        
                                        DEFINES += QT_DEPRECATED_WARNINGS
                                        SOURCES += \
                                                main.cpp \
                                                mainwindow.cpp
                                        
                                        HEADERS += \
                                                mainwindow.h
                                        
                                        FORMS += \
                                                mainwindow.ui
                                        
                                        

                                        Mainwindow is just a stock MainWindow with a menu item to start video capture.

                                        Let me know if this works.

                                        Hasan VaezH Offline
                                        Hasan VaezH Offline
                                        Hasan Vaez
                                        wrote on last edited by Hasan Vaez
                                        #24

                                        @mranger90
                                        Thank you for for taking these times.
                                        I think I found the problem.

                                        Camera sources uses some codes which is not compatible with some old camera and also with VMWare cams, as it uses some parameters which can not be found in old cams and VMware cams.

                                        VMWare cameras use USB 2.0 and 3.0 and can not set as USB 1.1.

                                        QCamera has high probability problem with VMWare and also with Cameras with USB 1.1!

                                        The finial test is to purchase a new Cam and test it in Linux.

                                        I think this problem comes from Hardware and all of my configs are set OK.

                                        If the problem become solved by changing a new Cam I should report it as s bug, Cuz some users use their QT written programs in VMWare machines.

                                        Would you please tell me whether you test your codes in VMWare or not?

                                        Thank and regards.

                                        1 Reply Last reply
                                        0
                                        • mranger90M Offline
                                          mranger90M Offline
                                          mranger90
                                          wrote on last edited by
                                          #25

                                          Yes, I set this up in a VMWare 12 player last night.
                                          Actually, it is very system and camera dependent.
                                          For instance, on my low powered home system I MUST set VMWare to use USB 1.1
                                          or there will be problems. That is the camera is recognized but not video will be displayed.
                                          Also, due to the low capabilities of my system, I do not get a valid display unless the camera is set to 320x240.
                                          I really don't believe this is a Qt issue because so much is dependent on the underlying system capabilities, both in hardware and software. Perhaps if you play around with the QViewFinder settings, you may find a combination that works.

                                          Hasan VaezH 1 Reply Last reply
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