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QT's QMediaRecorder not working - Unable to record from camera

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  • J jack1998

    @SGaist how can i check them please ?

    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by
    #11

    @jack1998

    ls -lh /dev/video4
    

    and see what user and groupd are set and also the access rights.

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

    J 1 Reply Last reply
    0
    • jsulmJ jsulm

      @jack1998

      ls -lh /dev/video4
      

      and see what user and groupd are set and also the access rights.

      J Offline
      J Offline
      jack1998
      wrote on last edited by
      #12

      @jsulm hello thank you for your replay, i find this result with the terminal in raspberry: crw-rw----+ 1 root video 81, 17 mai 4 12:01 /dev/video4

      jsulmJ 1 Reply Last reply
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      • J jack1998

        @jsulm hello thank you for your replay, i find this result with the terminal in raspberry: crw-rw----+ 1 root video 81, 17 mai 4 12:01 /dev/video4

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #13

        @jack1998 So, only root user and users which are member of the "video" group have access to /dev/video4
        Is your user member of that group (enter this command in terminal to check: groups).

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

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        • jsulmJ jsulm

          @jack1998 So, only root user and users which are member of the "video" group have access to /dev/video4
          Is your user member of that group (enter this command in terminal to check: groups).

          J Offline
          J Offline
          jack1998
          wrote on last edited by jack1998
          #14

          @jsulm thank you for your reply, i check it and i have access
          it is not a problem with the code please?

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          • J jack1998

            @jsulm thank you for your reply, i check it and i have access
            it is not a problem with the code please?

            J Offline
            J Offline
            jack1998
            wrote on last edited by
            #15

            what does that mean please ?
            GStreamer-CRITICAL **: 12:40:27.463:
            Trying to dispose element camera_source, but it is in PAUSED instead of the NULL state.
            You need to explicitly set elements to the NULL state before
            dropping the final reference, to allow them to clean up.
            This problem may also be caused by a refcounting bug in the
            application or some element.
            i m new with the qt :(

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            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #16

              Are you able to use that device from GStreamer directly ?
              Are there other applications trying to access it ?

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

              J 1 Reply Last reply
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              • SGaistS SGaist

                Are you able to use that device from GStreamer directly ?
                Are there other applications trying to access it ?

                J Offline
                J Offline
                jack1998
                wrote on last edited by jack1998
                #17

                @SGaist AL lib: (EE) ALCcaptureAlsa_open: Could not open capture device 'default': no such file or folder

                jsulmJ 1 Reply Last reply
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                • J jack1998

                  @SGaist AL lib: (EE) ALCcaptureAlsa_open: Could not open capture device 'default': no such file or folder

                  jsulmJ Offline
                  jsulmJ Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on last edited by
                  #18

                  @jack1998 said in QT's QMediaRecorder not working - Unable to record from camera:

                  AL lib: (EE) ALCcaptureAlsa_open: Could not open capture device 'default': no such file or folder

                  Is this coming when you try to access the device directly using GStreamer?

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

                  J 1 Reply Last reply
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                  • jsulmJ jsulm

                    @jack1998 said in QT's QMediaRecorder not working - Unable to record from camera:

                    AL lib: (EE) ALCcaptureAlsa_open: Could not open capture device 'default': no such file or folder

                    Is this coming when you try to access the device directly using GStreamer?

                    J Offline
                    J Offline
                    jack1998
                    wrote on last edited by
                    #19

                    @jsulm yes

                    J 1 Reply Last reply
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                    • J jack1998

                      @jsulm yes

                      J Offline
                      J Offline
                      jack1998
                      wrote on last edited by
                      #20

                      when I run the code in pi it works well however in root it does not work

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                      • SGaistS Offline
                        SGaistS Offline
                        SGaist
                        Lifetime Qt Champion
                        wrote on last edited by
                        #21

                        What do you mean by "in root" ?

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

                        1 Reply Last reply
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