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

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #9

    Did you check that you have access to the device(s) you are trying to use for recording ?

    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
    0
    • SGaistS SGaist

      Did you check that you have access to the device(s) you are trying to use for recording ?

      J Offline
      J Offline
      jack1998
      wrote on last edited by
      #10

      @SGaist how can i check them please ?

      jsulmJ 1 Reply Last reply
      0
      • 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
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        • 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
          0
          • 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

            J 1 Reply Last reply
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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?

              J 1 Reply Last reply
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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
                  0
                  • 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
                    0
                    • 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
                        0
                        • 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

                          1 Reply Last reply
                          0
                          • 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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