GStreamer: QGstreamerMediaCapture - make element state more robust

avoid setting elements to PLAYING, when the pipeline isn't playing

Pick-to: 6.6 6.5
Change-Id: I133e4f3fc0a32805c2394cbf96c9f84dca4c972c
Reviewed-by: Artem Dyomin <artem.dyomin@qt.io>
Reviewed-by: Jøger Hansegård <joger.hansegard@qt.io>
(cherry picked from commit c2e50467eee5a01efaadf3b0ea9cd893a3f2b784)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 6 insertions, 9 deletions

diff --git a/src/plugins/multimedia/gstreamer/mediacapture/qgstreamermediacapture.cpp b/src/plugins/multimedia/gstreamer/mediacapture/qgstreamermediacapture.cpp
index 6520272a6..86acfd07c 100644
--- a/src/plugins/multimedia/gstreamer/mediacapture/qgstreamermediacapture.cpp
+++ b/src/plugins/multimedia/gstreamer/mediacapture/qgstreamermediacapture.cpp
@@ -116,9 +116,7 @@ void QGstreamerMediaCapture::setCamera(QPlatformCamera *camera)
 
             qLinkGstElements(camera, gstVideoTee);
 
-            gstVideoOutput->gstElement().setState(GST_STATE_PLAYING);
-            gstVideoTee.setState(GST_STATE_PLAYING);
-            camera.setState(GST_STATE_PLAYING);
+            gstPipeline.syncChildrenState();
         }
     });
 
@@ -150,7 +148,7 @@ void QGstreamerMediaCapture::setImageCapture(QPlatformImageCapture *imageCapture
         if (m_imageCapture) {
             imageCaptureSink = m_imageCapture->gstElement().staticPad("sink");
             gstPipeline.add(m_imageCapture->gstElement());
-            m_imageCapture->gstElement().setState(GST_STATE_PLAYING);
+            m_imageCapture->gstElement().syncStateWithParent();
             linkTeeToPad(gstVideoTee, imageCaptureSink);
             m_imageCapture->setCaptureSession(this);
         }
@@ -197,7 +195,7 @@ void QGstreamerMediaCapture::linkEncoder(QGstPad audioSink, QGstPad videoSink)
 
             encoderVideoCapsFilter.src().link(videoSink);
             linkTeeToPad(gstVideoTee, encoderVideoCapsFilter.sink());
-            encoderVideoCapsFilter.setState(GST_STATE_PLAYING);
+            encoderVideoCapsFilter.syncStateWithParent();
             encoderVideoSink = encoderVideoCapsFilter.sink();
         }
 
@@ -213,7 +211,7 @@ void QGstreamerMediaCapture::linkEncoder(QGstPad audioSink, QGstPad videoSink)
 
             encoderAudioCapsFilter.src().link(audioSink);
             linkTeeToPad(gstAudioTee, encoderAudioCapsFilter.sink());
-            encoderAudioCapsFilter.setState(GST_STATE_PLAYING);
+            encoderAudioCapsFilter.syncStateWithParent();
             encoderAudioSink = encoderAudioCapsFilter.sink();
         }
     });
@@ -274,8 +272,7 @@ void QGstreamerMediaCapture::setAudioInput(QPlatformAudioInput *input)
                 linkTeeToPad(gstAudioTee, gstAudioOutput->gstElement().staticPad("sink"));
             }
 
-            gstAudioTee.setState(GST_STATE_PLAYING);
-            gstAudioInput->gstElement().setStateSync(GST_STATE_PLAYING);
+            gstPipeline.syncChildrenState();
 
             linkTeeToPad(gstAudioTee, encoderAudioSink);
         }
@@ -302,7 +299,7 @@ void QGstreamerMediaCapture::setAudioOutput(QPlatformAudioOutput *output)
         gstAudioOutput = static_cast<QGstreamerAudioOutput *>(output);
         if (gstAudioOutput && gstAudioInput) {
             gstPipeline.add(gstAudioOutput->gstElement());
-            gstAudioOutput->gstElement().setState(GST_STATE_PLAYING);
+            gstPipeline.syncChildrenState();
             linkTeeToPad(gstAudioTee, gstAudioOutput->gstElement().staticPad("sink"));
         }
     });