1 files changed, 23 insertions, 17 deletions

diff --git a/src/qtmultimediaquicktools/qdeclarativevideooutput.cpp b/src/qtmultimediaquicktools/qdeclarativevideooutput.cpp
index 32166502d..ca3a4b2ea 100644
--- a/src/qtmultimediaquicktools/qdeclarativevideooutput.cpp
+++ b/src/qtmultimediaquicktools/qdeclarativevideooutput.cpp
@@ -138,6 +138,7 @@ QDeclarativeVideoOutput::QDeclarativeVideoOutput(QQuickItem *parent) :
 {
     initResource();
     setFlag(ItemHasContents, true);
+    createBackend(nullptr);
 }
 
 QDeclarativeVideoOutput::~QDeclarativeVideoOutput()
@@ -148,6 +149,23 @@ QDeclarativeVideoOutput::~QDeclarativeVideoOutput()
 }
 
 /*!
+    \qmlproperty object QtMultimedia::VideoOutput::videoSurface
+    \since 5.15
+
+    This property holds the underlaying video surface that can be used
+    to render the video frames to this VideoOutput element.
+    It is similar to setting a QObject with \c videoSurface property as a source,
+    where this video surface will be set.
+
+    \sa source
+*/
+
+QAbstractVideoSurface *QDeclarativeVideoOutput::videoSurface() const
+{
+    return m_backend ? m_backend->videoSurface() : nullptr;
+}
+
+/*!
     \qmlproperty variant QtMultimedia::VideoOutput::source
 
     This property holds the source item providing the video frames like MediaPlayer or Camera.
@@ -206,21 +224,10 @@ void QDeclarativeVideoOutput::setSource(QObject *source)
             }
 
             m_sourceType = MediaObjectSource;
-#if QT_CONFIG(opengl)
         } else if (metaObject->indexOfProperty("videoSurface") != -1) {
-            // Make sure our backend is a QDeclarativeVideoRendererBackend
-            m_backend.reset();
-            createBackend(0);
-            Q_ASSERT(m_backend);
-#ifndef QT_NO_DYNAMIC_CAST
-            Q_ASSERT(dynamic_cast<QDeclarativeVideoRendererBackend *>(m_backend.data()));
-#endif
-            QAbstractVideoSurface * const surface = m_backend->videoSurface();
-            Q_ASSERT(surface);
             m_source.data()->setProperty("videoSurface",
-                                         QVariant::fromValue<QAbstractVideoSurface*>(surface));
+                QVariant::fromValue<QAbstractVideoSurface *>(videoSurface()));
             m_sourceType = VideoSurfaceSource;
-#endif
         } else {
             m_sourceType = NoSource;
         }
@@ -242,7 +249,8 @@ bool QDeclarativeVideoOutput::createBackend(QMediaService *service)
     const auto instances = videoBackendFactoryLoader()->instances(QLatin1String("declarativevideobackend"));
     for (QObject *instance : instances) {
         if (QDeclarativeVideoBackendFactoryInterface *plugin = qobject_cast<QDeclarativeVideoBackendFactoryInterface*>(instance)) {
-            m_backend.reset(plugin->create(this));
+            if (!m_backend)
+                m_backend.reset(plugin->create(this));
             if (m_backend && m_backend->init(service)) {
                 backendAvailable = true;
                 break;
@@ -251,7 +259,8 @@ bool QDeclarativeVideoOutput::createBackend(QMediaService *service)
     }
 #if QT_CONFIG(opengl)
     if (!backendAvailable) {
-        m_backend.reset(new QDeclarativeVideoRendererBackend(this));
+        if (!m_backend)
+            m_backend.reset(new QDeclarativeVideoRendererBackend(this));
         if (m_backend->init(service))
             backendAvailable = true;
     }
@@ -293,9 +302,6 @@ void QDeclarativeVideoOutput::_q_updateMediaObject()
     if (m_mediaObject.data() == mediaObject)
         return;
 
-    if (m_sourceType != VideoSurfaceSource)
-        m_backend.reset();
-
     m_mediaObject.clear();
     m_service.clear();