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video from Qt5 and C++ code example directly failed

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #2

    Hi,

    You need to provide more information like the exact version of Qt you are using, the name of the example, the Linux distribution you are using, the installed version of gstreamer etc.

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

    jerome_isAviableJ 1 Reply Last reply
    0
    • SGaistS SGaist

      Hi,

      You need to provide more information like the exact version of Qt you are using, the name of the example, the Linux distribution you are using, the installed version of gstreamer etc.

      jerome_isAviableJ Offline
      jerome_isAviableJ Offline
      jerome_isAviable
      wrote on last edited by jerome_isAviable
      #3

      @SGaist
      Hi Sgaist, thanks you for try to help (again and again):
      _archlinux kernel 4.3.3-3-ARCH
      _QT-5.5.1-9
      _gstreamer-1.6.3-1

      on laptop clevo intel i7 with nvidia GTX 950M graphic card and drivers: xf86-video-intel 2.99.917+519+g8229390-1, with nvidia 358.16-3 with bumblebee-3.2.1-10 (works fine).
      I also installed some lib32 drivers and mesa, mesa-libgl,
      libva-intel-driver (1.6.2-1), libva-mesa-driver (11.1.1-1),

      The Qt exemple use for try it is: "Camera Example"

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #4

        The first thing I'd do is try to run GStreamer from the console to see if it's working properly.

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

        jerome_isAviableJ 1 Reply Last reply
        0
        • SGaistS SGaist

          The first thing I'd do is try to run GStreamer from the console to see if it's working properly.

          jerome_isAviableJ Offline
          jerome_isAviableJ Offline
          jerome_isAviable
          wrote on last edited by
          #5

          @SGaist
          yes sure.
          It works (gstreamer).

          1 Reply Last reply
          0
          • SGaistS Offline
            SGaistS Offline
            SGaist
            Lifetime Qt Champion
            wrote on last edited by
            #6

            Ok, good. Can test that with a simpler version of the program e.g.

            int main(int argc, char *argv[])
            {
                QApplication app(argc, argv);
            
                QCamera camera;
                QCameraViewfinder viewfinder;
                viewfinder.show();
                camera.setViewfinder(&viewfinder);
                camera.start();
                return app.exec();
            }
            

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

            jerome_isAviableJ 1 Reply Last reply
            0
            • SGaistS SGaist

              Ok, good. Can test that with a simpler version of the program e.g.

              int main(int argc, char *argv[])
              {
                  QApplication app(argc, argv);
              
                  QCamera camera;
                  QCameraViewfinder viewfinder;
                  viewfinder.show();
                  camera.setViewfinder(&viewfinder);
                  camera.start();
                  return app.exec();
              }
              
              jerome_isAviableJ Offline
              jerome_isAviableJ Offline
              jerome_isAviable
              wrote on last edited by
              #7

              @SGaist
              yes, sure.
              I done it and it compil fine, run and never show camera or viewfinder, and it said back:

              libva info: VA-API version 0.38.1
              libva info: va_getDriverName() returns 0
              libva info: Trying to open /usr/lib/dri/i965_drv_video.so
              libva info: Found init function __vaDriverInit_0_38
              libva info: va_openDriver() returns 0

              but, if from your distribution (desktop version) linux it's runing fine, i think ther eis a problem, maybe not with QT5, but maybe with my configuration.
              The fact make me confused is also that, with qml code, camera and view work perfectly. That's strange.

              jerome_isAviableJ 1 Reply Last reply
              0
              • jerome_isAviableJ jerome_isAviable

                @SGaist
                yes, sure.
                I done it and it compil fine, run and never show camera or viewfinder, and it said back:

                libva info: VA-API version 0.38.1
                libva info: va_getDriverName() returns 0
                libva info: Trying to open /usr/lib/dri/i965_drv_video.so
                libva info: Found init function __vaDriverInit_0_38
                libva info: va_openDriver() returns 0

                but, if from your distribution (desktop version) linux it's runing fine, i think ther eis a problem, maybe not with QT5, but maybe with my configuration.
                The fact make me confused is also that, with qml code, camera and view work perfectly. That's strange.

                jerome_isAviableJ Offline
                jerome_isAviableJ Offline
                jerome_isAviable
                wrote on last edited by
                #8

                @SGaist
                ok, i think i find why this can not works.
                In fact, it is not QT5 directly, but the way it use video with (va-api) on my laptop.
                Because my laptop has two graphic proc (the one from intel from CPU chip, and the one from graphic card nvidia GTX950M).
                Then, i have to tell bumblebee to use nvidia card instead of intel GPU part of intel CPU due to impossibility by this intel proc to use these va-api (add an env variable for that in /etc/environment for example: LIBVA_DRIVER_NAME=nvidia).

                But maybe it could be possible also to configure QT5 tools to not use va-api lib for make running video on widgets ? is there a way to tell him to use the same way as it use with QML code ? If possible this way would be the best one for many situations (but not all for specific stuff maybe).

                1 Reply Last reply
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                • SGaistS Offline
                  SGaistS Offline
                  SGaist
                  Lifetime Qt Champion
                  wrote on last edited by
                  #9

                  If I understand you correctly, you have both working if running on the nVidia GPU but not when the Intel GPU is active ?

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

                  jerome_isAviableJ 1 Reply Last reply
                  0
                  • SGaistS SGaist

                    If I understand you correctly, you have both working if running on the nVidia GPU but not when the Intel GPU is active ?

                    jerome_isAviableJ Offline
                    jerome_isAviableJ Offline
                    jerome_isAviable
                    wrote on last edited by
                    #10

                    @SGaist not sure, i answer too quick and no had time more for experiment this way from laptop.

                    But from now, i work on my desktop PC, then only Intel video driver and CPU used for video (i7). And same problem: QCamear example running but show a black screen (no error output).

                    Then i see that there is no error with libva, but maybe the problem come from the use of libva by QT5.
                    I can not remove libva due to dependencies. How is it possible to make running/using video by an other way than libva for QT5 ?
                    I not understand because codes for video from QML sources works, not from QT/C++ sources (same problem from QT5 QCamera example).
                    maybe you could try to install a linux distribution in 64bits mode and install libva and gl libs, then just run the example give by QT5 to see the problem ?
                    or tell me what i could do for have more information around this kind of (maybe) bug.

                    appreciate your help, thanks.

                    1 Reply Last reply
                    0
                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #11

                      Qt 5.6 being almost out, can you check with it if you are still experiencing this ?
                      Otherwise, you should also check with the GStreamer 1.0 QtMultimedia plugin

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

                      jerome_isAviableJ 1 Reply Last reply
                      0
                      • SGaistS SGaist

                        Qt 5.6 being almost out, can you check with it if you are still experiencing this ?
                        Otherwise, you should also check with the GStreamer 1.0 QtMultimedia plugin

                        jerome_isAviableJ Offline
                        jerome_isAviableJ Offline
                        jerome_isAviable
                        wrote on last edited by
                        #12

                        @SGaist i just install the last one qt-5.6.0-1 from archlinux repos.
                        But same problem again.
                        I don't know what to do, i try to find help on irc from qt channel and archlinux channel, but no one help or find.
                        Do you have more idea ? is it possible to join a Qt dev of QtMultimedia or someone around this code ?

                        1 Reply Last reply
                        0
                        • SGaistS Offline
                          SGaistS Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on last edited by
                          #13

                          You can try writing to the interest mailing list

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

                          jerome_isAviableJ 1 Reply Last reply
                          0
                          • SGaistS SGaist

                            You can try writing to the interest mailing list

                            jerome_isAviableJ Offline
                            jerome_isAviableJ Offline
                            jerome_isAviable
                            wrote on last edited by
                            #14

                            @SGaist I tried... but:

                            This is an automatically generated Delivery Status Notification

                            THIS IS A WARNING MESSAGE ONLY.

                            YOU DO NOT NEED TO RESEND YOUR MESSAGE.

                            Delivery to the following recipient has been delayed:

                             interest@qt-project.com
                            

                            Message will be retried for 2 more day(s)

                            Technical details of temporary failure:
                            The recipient server did not accept our requests to connect. Learn more at https://support.google.com/mail/answer/7720
                            [qt-project.com. 77.240.23.85: socket error]

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

                              Did you subscribe first ?

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

                              jerome_isAviableJ 1 Reply Last reply
                              0
                              • SGaistS SGaist

                                Did you subscribe first ?

                                jerome_isAviableJ Offline
                                jerome_isAviableJ Offline
                                jerome_isAviable
                                wrote on last edited by
                                #16

                                @SGaist yes i suscribe first and then confirm my subscribtion.
                                But i have all the time error from send delivery mails.

                                also, i looked inside my directory: /usr/lib/dri
                                and i have this (who seems to be suspect i think):
                                https://gist.github.com/anonymous/dd17c9f72906726f8070b3d6a81a7a76

                                i installed nvidia before, but remove it and blacklisted it because of passthrough for qemu virtual machine (ability of use autocad with windows 7 on VM), but i use my intel driver. i not understand these libs on this directory.
                                Could you please tell me if you think it could be a problem there ?

                                1 Reply Last reply
                                0
                                • SGaistS Offline
                                  SGaistS Offline
                                  SGaist
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #17

                                  IIRC these are the libraries used by the Direct Rendering Infrastructure so I wouldn't say they are suspicious

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

                                  jerome_isAviableJ 1 Reply Last reply
                                  0
                                  • SGaistS SGaist

                                    IIRC these are the libraries used by the Direct Rendering Infrastructure so I wouldn't say they are suspicious

                                    jerome_isAviableJ Offline
                                    jerome_isAviableJ Offline
                                    jerome_isAviable
                                    wrote on last edited by jerome_isAviable
                                    #18

                                    @SGaist i tried to suscribe with an other account than gmail (from my own site):

                                    This is the mail system at host sortant-01.o2switch.net.
                                    
                                    I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.
                                    
                                    For further assistance, please send mail to postmaster.
                                    
                                    If you do so, please include this problem report. You can delete your own text from the attached returned message.
                                    
                                                       The mail system
                                    
                                    <interest@qt-project.com>: connect to qt-project.com[77.240.23.85]:25: No route to host
                                    
                                    

                                    It's look like a bad joke.... how to contact them ?
                                    Could you please post for me and explain i can not contact them ? what i can do ? i folow the process, it doesn't work att all.

                                    1 Reply Last reply
                                    0
                                    • SGaistS Offline
                                      SGaistS Offline
                                      SGaist
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #19

                                      Because it's qt-project.org not .com

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

                                      jerome_isAviableJ 2 Replies Last reply
                                      1
                                      • SGaistS SGaist

                                        Because it's qt-project.org not .com

                                        jerome_isAviableJ Offline
                                        jerome_isAviableJ Offline
                                        jerome_isAviable
                                        wrote on last edited by
                                        #20
                                        This post is deleted!
                                        1 Reply Last reply
                                        0
                                        • SGaistS SGaist

                                          Because it's qt-project.org not .com

                                          jerome_isAviableJ Offline
                                          jerome_isAviableJ Offline
                                          jerome_isAviable
                                          wrote on last edited by
                                          #21

                                          @SGaist Hi,
                                          after many month, i had to suscribe by two different email address, because one of them is like blacklisted or something like that (never seen my messages printed on the discussion).
                                          But anyway, with the second address, i saw it, but never have answer.

                                          When use the camera example code from Qt5, i know exactly the code line who make problem appears:
                                          "camera->setViewfinder(ui->viewfinder);"
                                          GPU is not the problem to.
                                          so consider the testcase is the QT5 example, with archlinux and last Qt-5.7.xxx on Intel CPU, with a usb camera who works with all other programms, and also with QML code. Juste the Qt5 with widgets code never works for me.
                                          Many month of search, never find solution, never find someone more than you that what to help on that to.

                                          IRC => no one answer on that to.

                                          i don't know what to do more, seems like use camera with Qt5 and widget code is a pain and it is like that.

                                          1 Reply Last reply
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