I am developing on a desktop as a host and the target is an iMX6 board. The OS for both is Ubuntu. I have ported the qmlvideofx example provided by Qt as a base application. From here, I want to add a QAbstractVideoFilter so that I can access the frames in the QMediaPlayer. I have two kits with this project, the Desktop Qt GCC 64bit (host) and an apalis-imx6 (target).

.h

Qt Code: 
  1. #ifndef VIDEOFILTERTOSATELLITE_H
  2. #define VIDEOFILTERTOSATELLITE_H
  3.  
  4. #include <QObject>
  5. #include <QAbstractVideoFilter>
  6. #include <QVideoFilterRunnable>
  7. #include <QDebug>
  8. #include <QSize>
  9.  
  10. class VideoFilterToSatellite;
  11.  
  12. class VideoFilterToSatelliteRunnable : public QVideoFilterRunnable
  13. {
  14.     public:
  15.         VideoFilterToSatelliteRunnable ( VideoFilterToSatellite* parent = 0 );
  16.         ~VideoFilterToSatelliteRunnable ();
  17.  
  18.         QVideoFrame run ( QVideoFrame *input,
  19.                           const QVideoSurfaceFormat &surfaceFormat,
  20.                           RunFlags flags ) Q_DECL_OVERRIDE;
  21.     private:
  22.         VideoFilterToSatellite* m_filterParent;
  23. };
  24.  
  25. class VideoFilterToSatellite : public QAbstractVideoFilter
  26. {
  27.     Q_OBJECT
  28.     public:
  29.         explicit VideoFilterToSatellite ( QAbstractVideoFilter *parent = 0 );
  30.         QVideoFilterRunnable* createFilterRunnable ();
  31. };
  32.  
  33. #endif // VIDEOFILTERTOSATELLITE_H
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.cpp

Qt Code: 
  1. #include "VideoFilterToSatellite.h"
  2.  
  3. VideoFilterToSatellite::VideoFilterToSatellite ( QAbstractVideoFilter *parent )
  4.     : QAbstractVideoFilter ( parent ) {}
  5.  
  6. QVideoFilterRunnable* VideoFilterToSatellite::createFilterRunnable ()
  7. {
  8.     return reinterpret_cast<QVideoFilterRunnable*>( new VideoFilterToSatelliteRunnable ( this ) );
  9. }
  10.  
  11. VideoFilterToSatelliteRunnable::VideoFilterToSatelliteRunnable ( VideoFilterToSatellite* parent )
  12.     : m_filterParent ( parent ) {}
  13.  
  14. VideoFilterToSatelliteRunnable::~VideoFilterToSatelliteRunnable() {}
  15.  
  16. QVideoFrame VideoFilterToSatelliteRunnable::run ( QVideoFrame *input,
  17.                                                   const QVideoSurfaceFormat &surfaceFormat,
  18.                                                   RunFlags flags )
  19. {
  20.     Q_UNUSED ( surfaceFormat );
  21.     Q_UNUSED ( flags );
  22.  
  23.     if (!input->isValid())
  24.         return *input;
  25.  
  26. // future work
  27.  
  28.     return *input;
  29. }
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.pro
Qt Code: 
  1. TEMPLATE = app
  2. TARGET = MCS_Host
  3.  
  4. QT += qml quick multimedia network
  5. CONFIG += c++11
  6. CONFIG += qml_debug
  7.  
  8. SOURCES += main.cpp \
  9.     filereader.cpp \
  10.     NetworkServer.cpp \
  11.     NetworkThread.cpp \
  12.     VideoFilterToSatellite.cpp
  13.  
  14. RESOURCES += qml.qrc
  15.  
  16. # Additional import path used to resolve QML modules in Qt Creator's code model
  17. QML_IMPORT_PATH =
  18.  
  19. # Default rules for deployment.
  20. qnx: target.path = /tmp/$${TARGET}/bin
  21. else: unix:!android: target.path = /opt/$${TARGET}/bin
  22. !isEmpty(target.path): INSTALLS += target
  23.  
  24. HEADERS += \
  25.     filereader.h \
  26.     NetworkServer.h \
  27.     NetworkThread.h \
  28.     trace.h \
  29.     VideoFilterToSatellite.h
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main.cpp

Qt Code: 
  1. ... includes ...
  2. #include "VideoFilterToSatellite.h"
  3.  
  4. int main(int argc, char *argv[])
  5. {
  6.     qputenv ( "QT_IM_MODULE", QByteArray ( "qtvirtualkeyboard" ) );
  7.  
  8.     qSetMessagePattern ( "\033[34m%{function}[%{line}]:\033[0m %{message}" );
  9.  
  10.     QGuiApplication app ( argc, argv );
  11.     qmlRegisterType<VideoFilterToSatellite>("VideoFilter.ToSatellite", 1, 0, "VideoFilterToSatellite" );
  12.  
  13.     QQuickView viewer;
  14.  
  15.     viewer.setSource ( QUrl ( QLatin1String ( "qrc:/qml/qmlvideofx/Main.qml" ) ) );
  16.  
  17.     viewer.show ();
  18.  
  19.     // Delay invocation of init until the event loop has started, to work around
  20.     // a GL context issue on Harmattan: without this, we get the following error
  21.     // when the first ShaderEffectItem is created:
  22.     // "QGLShaderProgram::addShader: Program and shader are not associated with same context"
  23.     QMetaObject::invokeMethod ( rootObject, "init", Qt::QueuedConnection );
  24.  
  25.     return app.exec();
  26. }
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If I run this code on the desktop, it all works. If I run it on the target, it immediately segfaults in dl-debug.c on line 46 dl_debug_initialize. If I take out the filter, everything works on both platforms. I am missing something and am unsure where to go from here. Thanks for any pointers.