[Speech] streamingRecognize for real time always hint: Shutdown has already been called

[zhongyzh]

I use SpeechApi to translate real time voice to text, and I uncounted the GRPC error, can give some suggestion:
static async Task StreamingMicRecognizeAsync(int seconds)
{
//if (NAudio.Wave.WaveIn.DeviceCount < 1)
//{
// Console.WriteLine("No microphone!");
// return -1;
//}
var speech = SpeechClient.Create();
var streamingCall = speech.StreamingRecognize(null, new BidirectionalStreamingSettings(10240));
// Write the initial request with the config.
try
{
await streamingCall.WriteAsync(
new StreamingRecognizeRequest()
{
StreamingConfig = new StreamingRecognitionConfig()
{
Config = new RecognitionConfig()
{
Encoding =
RecognitionConfig.Types.AudioEncoding.Linear16,
SampleRateHertz = 16000,
LanguageCode = "en",
},
InterimResults = true,
}
});
}
catch (Exception ex)
{

            Console.WriteLine("WriteAsync 0.error:{0:x}", ex.HResult);
        }

        // Print responses as they arrive.
        Task printResponses = Task.Run(async () =>
        {
            while (await streamingCall.ResponseStream.MoveNext(
                default(CancellationToken)))
            {
                foreach (var result in streamingCall.ResponseStream
                    .Current.Results)
                {
                    foreach (var alternative in result.Alternatives)
                    {
                        Console.WriteLine(alternative.Transcript);
                    }
                }
            }
        });
        // Read from the microphone and stream to API.
        object writeLock = new object();
        bool writeMore = true;
        var waveIn = new NAudio.Wave.WasapiCaptureRT();
        //waveIn.DeviceNumber = 0;
        waveIn.WaveFormat = new NAudio.Wave.WaveFormat(48000, 2);
       
        waveIn.DataAvailable +=
            (object sender, NAudio.Wave.WaveInEventArgs args) =>
            {
                lock (writeLock)
                {
                    if (!writeMore)
                        return;
                    Console.WriteLine("recording:{0:d}", args.BytesRecorded);
                     
                    byte[] newBuffer = new byte[args.BytesRecorded / 6];
                    for (int i = 0; i < args.BytesRecorded / 6; i +=6)
                    {
                        UInt16 first = (UInt16)((args.Buffer[i * 2 + 1] << 8) | args.Buffer[i * 2]);
                        UInt16 second = (UInt16)((args.Buffer[i * 2 + 5] << 8) | args.Buffer[i * 2+4]);
                        UInt16 third = (UInt16)((args.Buffer[i * 2 + 9] << 8) | args.Buffer[i * 2+8]);
                        UInt16 newOne = (UInt16)((UInt32)(first + second + third) / 3);
                        newBuffer[i] = (byte)(newOne & 0X08);
                        newBuffer[i+1] = (byte)(newOne >> 8 );
                    }
                    StreamingRecognizeRequest request = new StreamingRecognizeRequest()
                    {
                        AudioContent = Google.Protobuf.ByteString.CopyFrom(newBuffer, 0, args.BytesRecorded / 6)
                    };
                    try
                    {
                        streamingCall.WriteAsync(request).Wait();
                    }
                    catch (Exception ex)
                    {

                        Console.WriteLine("WriteAsync.error:{0:x}",ex.HResult);
                    }
                }

            };
        //waveIn.RecordingStopped += (object sender, StoppedEventArgs stoppedEventArgs) =>
        //{

        //};
        waveIn.StartRecording();
        Console.WriteLine("Speak now.");
        await Task.Delay(TimeSpan.FromSeconds(seconds));
        // Stop recording and shut down.
        waveIn.StopRecording();
        lock (writeLock) writeMore = false;
        await streamingCall.WriteCompleteAsync();
        await printResponses;
        return 0;
    } 

[zhongyzh]

At this line: streamingCall.WriteAsync(request).Wait(); will receive the exception.

[dwsupplee]

@zhongyzh, it looks like you want to direct this issue towards https://github.com/googlecloudplatform/google-cloud-dotnet.