readFrame

examples/streamer/streamer.cpp

@@ -59,17 +59,18 @@ void AppSrc::imageReady()
     m_grabResult.reset();
 }
 
-QVideoFrame AppSrc::readFrame() const
+bool AppSrc::readFrame(QVideoFrame &frame) const
 {
     if (!m_frame.isValid() && m_streamer->item()) {
         m_grabResult = qobject_cast<QQuickItem*>(m_streamer->item())->grabToImage();
         connect(m_grabResult.data(), &QQuickItemGrabResult::ready, this, &AppSrc::imageReady);
+        return false;
     }
 
-    auto frame = m_frame;
+    frame = m_frame;
     m_frame = QVideoFrame();
 
-    return frame;
+    return true;
 }
 
 Streamer::Streamer(QObject *parent)

examples/streamer/streamer.h

@@ -70,7 +70,7 @@ public:
     }
 
 protected:
-    QVideoFrame readFrame() const override;
+    bool readFrame(QVideoFrame &frame) const override;
 
 private Q_SLOTS:
     void imageReady();

src/gstreamerextras/qgstreamerappsrc.cpp

@@ -122,9 +122,10 @@ void QGstreamerAppSrc::stopFeed()
     d->timerId = 0;
 }
 
-QVideoFrame QGstreamerAppSrc::readFrame() const
+bool QGstreamerAppSrc::readFrame(QVideoFrame &frame) const
 {
-    return QVideoFrame();
+    Q_UNUSED(frame);
+    return false;
 }
 
 void QGstreamerAppSrc::timerEvent(QTimerEvent *event)
@@ -134,8 +135,8 @@ void QGstreamerAppSrc::timerEvent(QTimerEvent *event)
     if (event->timerId() != d->timerId)
         return;
 
-    QVideoFrame frame = readFrame();
-    if (!frame.isValid() || (d->size != frame.size() && !d->restart(frame)))
+    QVideoFrame frame;
+    if (!readFrame(frame) || !frame.isValid() || (d->size != frame.size() && !d->restart(frame)))
         return;
 
     if (!frame.map(QAbstractVideoBuffer::ReadOnly))

src/gstreamerextras/qgstreamerappsrc.h

@@ -54,7 +54,7 @@ public:
     ~QGstreamerAppSrc();
 
 protected:
-    virtual QVideoFrame readFrame() const;
+    virtual bool readFrame(QVideoFrame &frame) const;
 
 private Q_SLOTS:
     void startFeed();