AudioGraph 在第二帧输入节点上抛出 XAUDIO2_E_INVALID_CALL

Question

我正在尝试使用 UWP 的 AudioGraph API 来重现合成语音和短通知声音的混合 ("earcons")。

UWP 有一个语音合成 API，它给我一个包含 WAV 文件的流，但我不想对参数（比特率、采样深度等）做太多假设，所以这个想法是有一个 AudioSubmixNode 并添加 AudioFrameInputNodes 每当有一些演讲要重现时。将单独的话语排队以使其不重叠存在一些复杂性。

图表初始化为

    private async Task InitAudioGraph()
    {
        var graphCreated = await AudioGraph.CreateAsync(new AudioGraphSettings(Windows.Media.Render.AudioRenderCategory.Speech)
        {
            QuantumSizeSelectionMode = QuantumSizeSelectionMode.LowestLatency
        });
        if (graphCreated.Status != AudioGraphCreationStatus.Success) return;

        _Graph = graphCreated.Graph;
        var outputCreated = await _Graph.CreateDeviceOutputNodeAsync();
        if (outputCreated.Status != AudioDeviceNodeCreationStatus.Success) return;

        _Mixer = _Graph.CreateSubmixNode();
        _Mixer.AddOutgoingConnection(outputCreated.DeviceOutputNode);

        _Graph.Start();
    }

然后用

播放当前的话语

class SpeechStreamPlayer : IDisposable
{
    internal static void Play(AudioGraph graph, AudioSubmixNode mixer, SpeechSynthesisStream speechStream)
    {
        if (!speechStream.ContentType.Equals("audio/wav", StringComparison.OrdinalIgnoreCase)) throw new NotSupportedException("Content type: " + speechStream.ContentType);

        var stream = speechStream.AsStreamForRead();

        // Read the RIFF header
        uint chunkId = stream.ReadUint(); // "RIFF" - but in little-endian
        if (chunkId != 0x46464952) throw new NotSupportedException("Magic: " + chunkId);
        uint chunkSize = stream.ReadUint(); // Length of rest of stream
        uint format = stream.ReadUint(); // "WAVE"
        if (format != 0x45564157) throw new NotSupportedException("Stream format: " + format);

        // "fmt " sub-chunk
        uint subchunkId = stream.ReadUint();
        if (subchunkId != 0x20746d66) throw new NotSupportedException("Expected fmt sub-chunk, found " + subchunkId);
        uint subchunkSize = stream.ReadUint();
        uint subchunk2Off = (uint)stream.Position + subchunkSize;
        uint audioFormat = (uint)stream.ReadShort();
        uint chans = (uint)stream.ReadShort();
        uint sampleRate = stream.ReadUint();
        uint byteRate = stream.ReadUint();
        uint blockSize = (uint)stream.ReadShort();
        uint bitsPerSample = (uint)stream.ReadShort();

        // Possibly extra stuff added, so...
        stream.Seek(subchunk2Off, SeekOrigin.Begin);

        subchunkId = stream.ReadUint(); // "data"
        if (subchunkId != 0x61746164) throw new NotSupportedException("Expected data sub-chunk, found " + subchunkId);
        subchunkSize = stream.ReadUint();

        // Ok, the stream is in the correct place to start extracting data and we have the parameters.
        var props = AudioEncodingProperties.CreatePcm(sampleRate, chans, bitsPerSample);

        var frameInputNode = graph.CreateFrameInputNode(props);
        frameInputNode.AddOutgoingConnection(mixer);

        new SpeechStreamPlayer(frameInputNode, mixer, stream, blockSize);
    }

    internal event EventHandler StreamFinished;

    private SpeechStreamPlayer(AudioFrameInputNode frameInputNode, AudioSubmixNode mixer, Stream stream, uint sampleSize)
    {
        _FrameInputNode = frameInputNode;
        _Mixer = mixer;
        _Stream = stream;
        _SampleSize = sampleSize;

        _FrameInputNode.QuantumStarted += Source_QuantumStarted;
        _FrameInputNode.Start();
    }

    private AudioFrameInputNode _FrameInputNode;
    private AudioSubmixNode _Mixer;
    private Stream _Stream;
    private readonly uint _SampleSize;

    private unsafe void Source_QuantumStarted(AudioFrameInputNode sender, FrameInputNodeQuantumStartedEventArgs args)
    {
        if (args.RequiredSamples <= 0) return;
        System.Diagnostics.Debug.WriteLine("Requested {0} samples", args.RequiredSamples);

        var frame = new AudioFrame((uint)args.RequiredSamples * _SampleSize);
        using (var buffer = frame.LockBuffer(AudioBufferAccessMode.Write))
        {
            using (var reference = buffer.CreateReference())
            {
                byte* pBuffer;
                uint capacityBytes;

                var directBuffer = reference as IMemoryBufferByteAccess;
                ((IMemoryBufferByteAccess)reference).GetBuffer(out pBuffer, out capacityBytes);

                uint bytesRemaining = (uint)_Stream.Length - (uint)_Stream.Position;
                uint bytesToCopy = Math.Min(capacityBytes, bytesRemaining);

                for (uint i = 0; i < bytesToCopy; i++) pBuffer[i] = (byte)_Stream.ReadByte();
                for (uint i = bytesToCopy; i < capacityBytes; i++) pBuffer[i] = 0;

                if (bytesRemaining <= capacityBytes)
                {
                    Dispose();
                    StreamFinished?.Invoke(this, EventArgs.Empty);
                }
            }
        }

        sender.AddFrame(frame);
    }

    public void Dispose()
    {
        if (_FrameInputNode != null)
        {
            _FrameInputNode.QuantumStarted -= Source_QuantumStarted;
            _FrameInputNode.Dispose();
            _FrameInputNode = null;
        }

        if (_Stream != null)
        {
            _Stream.Dispose();
            _Stream = null;
        }
    }
}

这一次有效。当第一个话语结束时，StreamFinished?.Invoke(this, EventArgs.Empty); 通知队列管理系统应该播放下一个话语，并且行

    var frameInputNode = graph.CreateFrameInputNode(props);

抛出 Exception 消息 Exception from HRESULT: 0x88960001。一些挖掘表明 it corresponds to XAUDIO2_E_INVALID_CALL，但这不是很具体。

在这两种情况下，传递给 AudioEncodingProperties.CreatePcm 的参数都是 (22050, 1, 16)。

我怎样才能找到有关问题所在的更多详细信息？在最坏的情况下，我想我可以扔掉整个图表并每次构建一个新图表，但这似乎效率很低。

Answer 1

问题好像出在

When the first utterance finishes, the StreamFinished?.Invoke(this, EventArgs.Empty); notifies the queue management system that the next utterance should be played

尽管 AudioFrameInputNode.QuantumStarted doesn't say anything about forbidden actions, the docs for AudioGraph.QuantumStarted 的文档说

The QuantumStarted event is synchronous, which means that you can't update the properties or state of the AudioGraph or the individual audio nodes in the handler for this event. Attempting perform an operation such as stopping the audio graph or adding, removing, or starting an individual audio node will result in an exception being thrown.

看来这也适用于节点的 QuantumStarted 事件。

简单的解决方案是将图形操作移动到另一个线程

                        Task.Run(() => StreamFinished?.Invoke(this, EventArgs.Empty));

AudioGraph 在第二帧输入节点上抛出 XAUDIO2_E_INVALID_CALL

AudioGraph throws XAUDIO2_E_INVALID_CALL on second frame input node

uwp

audio-player

xaudio2