Use resume/suspend from audio output to preserve audio resources

include/f1x/openauto/autoapp/Projection/AudioOutput.hpp

@@ -42,23 +42,27 @@ public:
     void write(const aasdk::common::DataConstBuffer& buffer) override;
     void start() override;
     void stop() override;
+    void suspend() override;
     uint32_t getSampleSize() const override;
     uint32_t getChannelCount() const override;
     uint32_t getSampleRate() const override;
 
 signals:
     void startPlayback();
+    void suspendPlayback();
     void stopPlayback();
 
 protected slots:
     void createAudioOutput();
     void onStartPlayback();
+    void onSuspendPlayback();
     void onStopPlayback();
 
 private:
     QAudioFormat audioFormat_;
     SequentialBuffer audioBuffer_;
     std::unique_ptr<QAudioOutput> audioOutput_;
+    bool playbackStarted_;
 };
 
 }

include/f1x/openauto/autoapp/Projection/IAudioOutput.hpp

@@ -42,6 +42,7 @@ public:
     virtual void write(const aasdk::common::DataConstBuffer& buffer) = 0;
     virtual void start() = 0;
     virtual void stop() = 0;
+    virtual void suspend() = 0;
     virtual uint32_t getSampleSize() const = 0;
     virtual uint32_t getChannelCount() const = 0;
     virtual uint32_t getSampleRate() const = 0;

src/autoapp/Projection/AudioOutput.cpp

@@ -30,6 +30,7 @@ namespace projection
 {
 
 AudioOutput::AudioOutput(uint32_t channelCount, uint32_t sampleSize, uint32_t sampleRate)
+    : playbackStarted_(false)
 {
     audioFormat_.setChannelCount(channelCount);
     audioFormat_.setSampleRate(sampleRate);
@@ -40,6 +41,7 @@ AudioOutput::AudioOutput(uint32_t channelCount, uint32_t sampleSize, uint32_t sa
 
     this->moveToThread(QApplication::instance()->thread());
     connect(this, &AudioOutput::startPlayback, this, &AudioOutput::onStartPlayback);
+    connect(this, &AudioOutput::suspendPlayback, this, &AudioOutput::onSuspendPlayback);
     connect(this, &AudioOutput::stopPlayback, this, &AudioOutput::onStopPlayback);
 
     QMetaObject::invokeMethod(this, "createAudioOutput", Qt::BlockingQueuedConnection);
@@ -74,6 +76,11 @@ void AudioOutput::stop()
     emit stopPlayback();
 }
 
+void AudioOutput::suspend()
+{
+    emit suspendPlayback();
+}
+
 uint32_t AudioOutput::getSampleSize() const
 {
     return audioFormat_.sampleSize();
@@ -91,14 +98,31 @@ uint32_t AudioOutput::getSampleRate() const
 
 void AudioOutput::onStartPlayback()
 {
-    audioOutput_->start(&audioBuffer_);
+    if(!playbackStarted_)
+    {
+        audioOutput_->start(&audioBuffer_);
+        playbackStarted_ = true;
+    }
+    else
+    {
+        audioOutput_->resume();
+    }
 }
 
-void AudioOutput::onStopPlayback()
+void AudioOutput::onSuspendPlayback()
 {
     audioOutput_->suspend();
 }
 
+void AudioOutput::onStopPlayback()
+{
+    if(playbackStarted_)
+    {
+        audioOutput_->stop();
+        playbackStarted_ = false;
+    }
+}
+
 }
 }
 }

src/autoapp/Projection/AudioService.cpp

@@ -142,7 +142,7 @@ void AudioService::onAVChannelStopIndication(const aasdk::proto::messages::AVCha
                        << ", channel: " << aasdk::messenger::channelIdToString(channel_->getId())
                        << ", session: " << session_;
     session_ = -1;
-    audioOutput_->stop();
+    audioOutput_->suspend();
     channel_->receive(this->shared_from_this());
 }