Exemplo n.º 1
0
        public async Task Start()
        {
            m_isFlushing       = false;
            m_isRunning        = false;
            m_waveBufferReader = null;

            var settings = new AudioGraphSettings(AudioRenderCategory.Media);
            var result   = await AudioGraph.CreateAsync(settings);

            if (result.Status != AudioGraphCreationStatus.Success)
            {
                throw new Exception("AudioGraph creation error: " + result.Status);
            }

            m_audioGraph = result.Graph;


            var outputDeviceResult = await m_audioGraph.CreateDeviceOutputNodeAsync();

            if (outputDeviceResult.Status != AudioDeviceNodeCreationStatus.Success)
            {
                throw new Exception("Unable to create audio playback device: " + result.Status);
            }

            m_deviceOutputNode = outputDeviceResult.DeviceOutputNode;

            // Create the FrameInputNode at the same format as the graph,
            var nodeEncodingProperties = m_audioGraph.EncodingProperties;

            nodeEncodingProperties.ChannelCount = 1;
            nodeEncodingProperties.SampleRate   = 16000;
            m_frameInputNode = m_audioGraph.CreateFrameInputNode(nodeEncodingProperties);
            m_frameInputNode.AddOutgoingConnection(m_deviceOutputNode);
            m_frameInputNode.QuantumStarted += OnQuantumStarted;

            m_isRunning  = true;
            m_isFlushing = false;
            m_audioGraph.Start();
        }
Exemplo n.º 2
0
        private unsafe AudioFrame GenerateAudioData(int samples)
        {
            var frame = new AudioFrame((uint)samples * sizeof(float));

            try
            {
                using (var buffer = frame.LockBuffer(AudioBufferAccessMode.Read))
                    using (var reference = buffer.CreateReference())
                    {
                        byte * dataInBytes;
                        uint   capacity;
                        float *dataInFloat;

                        // Get the buffer from the AudioFrame
                        ((IMemoryBufferByteAccess)reference).GetBuffer(out dataInBytes, out capacity);
                        dataInFloat = (float *)dataInBytes;

                        var sampleIndex = 0;
                        while ((m_audioData.Count() > 0 || m_waveBufferReader != null) && sampleIndex < samples)
                        {
                            // extract the next audio buffer from the queue
                            if (m_waveBufferReader == null)
                            {
                                m_audioDataMutex.WaitOne();
                                m_waveBufferReader = WaveBufferReader.Create(m_audioData[0]);
                                m_audioData.RemoveAt(0);
                                m_audioDataMutex.ReleaseMutex();
                            }

                            // read samples from WaveBufferReader until output buffer is full
                            // or input buffer is empty
                            var eof = false;
                            while (sampleIndex < samples && !eof)
                            {
                                var temp = m_waveBufferReader.ReadShort(ref eof);
                                if (!eof)
                                {
                                    dataInFloat[sampleIndex++] = temp / 32768.0f;
                                }
                                else
                                {
                                    // current reader is empty so delete it
                                    m_waveBufferReader = null;
                                }
                            }
                        }

                        // fill remainder of buffer with silence
                        while (sampleIndex < samples)
                        {
                            dataInFloat[sampleIndex++] = 0.0f;
                            // check if we are done flushing audio after Stop()
                            if (!m_isRunning && m_isFlushing && m_audioData.Count() == 0 && m_waveBufferReader == null)
                            {
                                m_isFlushing = false;
                            }
                        }
                    }
            }

            catch (Exception ex)
            {
                Debug.WriteLine(ex.Message);
            }

            return(frame);
        }