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Unable to play a wav file with Audio component

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qt5.5.1colibri-t20
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  • zyendZ Offline
    zyendZ Offline
    zyend
    wrote on last edited by zyend
    #3

    SGaist,

    Before recompîling Qt5.51 without pulseaudio, I had the following message in the console:

    PulseAudioService: pa_context_connect() failed
    

    Unfortunately, recompiling without pulseaudio doesnot display the message anymore...but it doesn't fix anything. I can't hear anything :(

    K.

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    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #4

      Do you have Pulseaudio running on your device ?

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

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      • zyendZ Offline
        zyendZ Offline
        zyend
        wrote on last edited by
        #5

        No.
        I've removed "pulseaudio" from the Yocto generated Distro.

        But the command line:

        aplay /opt/track.wav
        

        still works though...

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        • SGaistS Offline
          SGaistS Offline
          SGaist
          Lifetime Qt Champion
          wrote on last edited by
          #6

          Because it's using ALSA directly.

          Did you try to build the ALSA backend for Qt Multimedia ?

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

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          • zyendZ Offline
            zyendZ Offline
            zyend
            wrote on last edited by
            #7

            Yes, I think so.

            I can find libqtaudio_alsa.so in /usr/lib/qt/plugins.

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            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #8

              Start your application with QT_DEBUG_PLUGINS=1 to see if there's a problem when loading the plugin.

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

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              • zyendZ Offline
                zyendZ Offline
                zyend
                wrote on last edited by
                #9

                At first glance, the plugins get loaded.

                Got keys from plugin meta data ("alsa")
                QFactoryLoader::QFactoryLoader() looking at "/usr/lib/qt5/plugins/audio/libqtaudio_alsa.so.new"
                Found metadata in lib /usr/lib/qt5/plugins/audio/libqtaudio_alsa.so.new, metadata=
                {
                    "IID": "org.qt-project.qt.audiosystemfactory/5.0",
                    "MetaData": {
                        "Keys": [
                            "alsa"
                        ]
                    },
                    "className": "QAlsaPlugin",
                    "debug": false,
                    "version": 328961
                }
                
                
                Got keys from plugin meta data ("alsa")
                QFactoryLoader::QFactoryLoader() checking directory path "/opt/pga/audio" ...
                loaded library "/usr/lib/qt5/plugins/audio/libqtaudio_alsa.so"
                

                :(

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                • SGaistS Offline
                  SGaistS Offline
                  SGaist
                  Lifetime Qt Champion
                  wrote on last edited by
                  #10

                  Looks good on that point.

                  Did you check which output QtMultimedia sees as available ?

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

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                  • zyendZ Offline
                    zyendZ Offline
                    zyend
                    wrote on last edited by
                    #11

                    What do you mean exactly ?

                    Yesterday, in the main.cpp, I dumped the

                    QAudioDeviceInfo::availableDevices(QAudio::AudioOutput)
                    

                    Is that what you meant ? And yes, it dumps the same devices as with

                    aplay -L
                    
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                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #12

                      That's that yes and the result also looks good.

                      Did you check whether the element raises an error ?

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

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                      • zyendZ Offline
                        zyendZ Offline
                        zyend
                        wrote on last edited by
                        #13

                        No error raised.

                        However, in the onClick() handler where idPlay->play() is launched (see code snippet above..),
                        I traced the values of some properties of tha Audio component.

                        qml: status =  2
                        qml: playvolume =  1
                        qml: muted =  false
                        qml: error code =  0 , string=
                        qml: src =  file:///opt/pga/track00.wav
                        qml: availability =  0
                        qml: duration =  -1
                        qml: hasAudio =  false
                        

                        Weird. duration = -1, hasAudio = false and however, no error code / string...

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                        • SGaistS Offline
                          SGaistS Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on last edited by
                          #14

                          The path to the file looks different from your QML sample code.

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

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                          • zyendZ Offline
                            zyendZ Offline
                            zyend
                            wrote on last edited by
                            #15

                            Yes, because I changed the path between my tests, but the paths are valids.

                            I really don't understand why Qt does not raise any error.
                            Everything looks correct.
                            status = 2, that is: "the Media has been loaded".

                            So it looks like a final phase is not complete. Isn't it ?

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

                              Can you test the functionality with C++ ?

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

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                              • zyendZ Offline
                                zyendZ Offline
                                zyend
                                wrote on last edited by zyend
                                #17

                                I've put this sample code in the C++ side:

                                init()
                                {
                                ...
                                 connect(&m_player, SIGNAL(error(QMediaPlayer::Error)), this, SLOT(on_mediaPlayer_error(QMediaPlayer::Error)));^
                                 connect(&m_player, SIGNAL(stateChanged(QMediaPlayer::State)), this, SLOT(on_mediaPlayer_stateChanged(QMediaPlayer::State)));^
                                 connect(&m_player, SIGNAL(mediaStatusChanged(QMediaPlayer::MediaStatus)), this, 
                                SLOT(on_mediaPlayer_mediaStatusChanged(QMediaPlayer::MediaStatus)));
                                
                                qDebug() << "Attempt to read mediacontent";
                                QMediaContent content(QUrl::fromLocalFile("/opt/pga/track00.wav"));
                                qDebug() << "MediaContent: isNull = " << content.isNull();
                                m_player.setMedia(content);
                                m_player.play();
                                }
                                

                                Each of the slots above print the value of their respective parameter in stdout.

                                Output from my host linux:

                                Attempt to read mediacontent
                                MediaContent: isNull =  false
                                <MainWindow::on_mediaPlayer_mediaStatusChanged> status =  QMediaPlayer::LoadingMedia
                                <MainWindow::on_mediaPlayer_stateChanged> state =  QMediaPlayer::PlayingState
                                <MainWindow::on_mediaPlayer_mediaStatusChanged> status =  QMediaPlayer::BufferedMedia
                                

                                Output from my colibri-t20:

                                Attempt to read mediacontent
                                MediaContent: isNull =  false
                                <MainWindow::on_mediaPlayer_mediaStatusChanged> status =  QMediaPlayer::LoadingMedia
                                

                                It's stuck on LoadingMedia.
                                No more.

                                :(

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                                • SGaistS Offline
                                  SGaistS Offline
                                  SGaist
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #18

                                  Ok...

                                  You should rebuilt the plugin uncommenting the DEBUG_AUDIO define to see if it gives you more information about what is happening.

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

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                                  • zyendZ Offline
                                    zyendZ Offline
                                    zyend
                                    wrote on last edited by
                                    #19

                                    Hi,

                                    Unfortunately it doesn't trace more information at all...

                                    Found metadata in lib /usr/lib/qt5/plugins/audio/libqtaudio_alsa.so, metadata=
                                    {
                                        "IID": "org.qt-project.qt.audiosystemfactory/5.0",
                                        "MetaData": {
                                            "Keys": [
                                                "alsa"
                                            ]
                                        },
                                        "className": "QAlsaPlugin",
                                        "debug": false,
                                        "version": 328961
                                    }
                                    
                                    
                                    Got keys from plugin meta data ("alsa")
                                    QFactoryLoader::QFactoryLoader() checking directory path "/opt/pga/audio" ...
                                    loaded library "/usr/lib/qt5/plugins/audio/libqtaudio_alsa.so"
                                    DeviceInfo name =  "sysdefault:CARD=colibrit20wm971" , codecs =  "audio/pcm"
                                    DeviceInfo name =  "default:CARD=colibrit20wm971" , codecs =  "audio/pcm"
                                    DeviceInfo name =  "default" , codecs =  "audio/pcm"
                                    Default OutputDevice:  "sysdefault:CARD=colibrit20wm971"
                                    Attempt to read mediacontent
                                    MediaContent: isNull =  false
                                    <MainWindow::on_mediaPlayer_mediaStatusChanged> status =  QMediaPlayer::LoadingMedia , bufferStatus =  0
                                    <MainWindow::initialize()> : bufferStatus =  0
                                    screen dpi =  96.1517
                                    screen geo =  QRect(0,0 480x800)
                                    QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/qt5/plugins/accessiblebridge" ...
                                    QFactoryLoader::QFactoryLoader() checking directory path "/opt/pga/accessiblebridge" ...
                                    QSGContext::initialize: stencil buffer support missing, expect rendering errors
                                    Updating catalog.
                                    <MediaCatalog::roleNames() > called.
                                    qml: size of catalog:  3
                                    qml: playlaunched...status =  1
                                    qml: playvolume =  1
                                    qml: muted =  false
                                    qml: error code =  0 , string=
                                    qml: src =
                                    qml: availability =  0
                                    qml: duration =  -1
                                    qml: hasAudio =  false
                                    
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                                    • SGaistS Offline
                                      SGaistS Offline
                                      SGaist
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #20

                                      Does the device info look correct for your system ?
                                      Can you compare with that aplay uses ?

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

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                                      • zyendZ Offline
                                        zyendZ Offline
                                        zyend
                                        wrote on last edited by
                                        #21

                                        Yes, it is always the same.

                                        I have also edited the qalsaaudiooutput.cpp and added some fprintf() statements and nothing is displayed in the console.
                                        I put a message in open() and in the constructor

                                        However, it prints loaded library "/usr/lib/qt5/plugins/audio/libqtaudio_alsa.so"

                                        I don't know what I can do to figure out what's happening.

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                                        • SGaistS Offline
                                          SGaistS Offline
                                          SGaist
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #22

                                          Did you install the plugin properly after having built it ?

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

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