Audio Input

In addition to pushing text, a client may provide the session input by using audio.

Creating the Audio Input Stream

To provide the session with audio input, the client code should first create the input stream. For a given session, only a single audio input stream should be open at a time, but it perfectly acceptable to open and close multiple audio streams over the course of a single session.

    
// Create the stream using the client and session ID
stream, err := client.StreamAudioInput(context.Background(), sessionID)

// OR create the stream using the Session object
stream, err := session.StreamAudioInput(context.Background())

    
std::unique_ptr<Diatheke::AudioInputStream> stream;

// Create the stream using the client and session ID
stream = client.streamAudioInput(sessionID);

// OR create the stream using the Session object
stream = session.streamAudioInput();

    
# Create the stream using the client and session ID
stream = client.stream_audio_input(session_id)

# OR create the stream using the Session object
stream = session.stream_audio_input()

    
# Create the stream using the client and session ID
let stream = client.streamAudioInput(sessionID: sessionID) { (error) in
        print(error.localizedDescription)
}

# OR create the stream using the Session object
let stream = session.streamAudioInput { (error) in
        print(error.localizedDescription)
}

    
StreamObserver<DiathekeOuterClass.AudioInput> audioInputStreamObserver = mClient.streamAudioInput(new StreamObserver<DiathekeOuterClass.Empty>() {
            @Override
            public void onNext(DiathekeOuterClass.Empty value) {

            }

            @Override
            public void onError(Throwable t) {

            }

            @Override
            public void onCompleted() {

            }
        });

    Pushing Audio

    It is the client code’s responsibility to handle getting audio data, whether it is from a microphone, file, or some other source. Audio input should be formatted and encoded based on the specific ASR model being used for the session (as defined in the Diatheke server config file). The audio data may then be sent to the server using the stream created previously.

      
// The audio data should be formatted as an array of bytes.
buffer := make([]byte, 8192)

// Get the audio data from a source. This could be a microphone, file, or
// any other source. Here we assume the audio data was retrieved previously
// and stored in our buffer.

// Push the audio data to the input stream. This function may be called
// multiple times.
bytesWritten, err := stream.Write(buffer);

// Be sure to notify Diatheke that no more audio will be coming when we
// are done writing data.
err := stream.Finish();

      
// Store audio data as a string. Think of the string as an array of chars
// or bytes (a char is one byte of data).
std::string buffer;

// Get the audio data from a source. This could be a microphone, file, or
// any other source. Here we assume the audio data was retrieved previously
// and stored in our buffer.

// Push the audio data to the input stream. This function may be called
// multiple times.
stream->pushAudio(buffer.c_str(), buffer.size());

// Be sure to notify Diatheke that no more audio will be coming when we
// are done writing data.
stream->finished();

      
# Get the audio data from a source. This could be a microphone, file, or
# any other source. Here we assume the audio data was retrieved previously
# and stored in a buffer.

# Push the audio data to the input stream. This function may be called
# multiple times.
stream.write(buffer)

# Be sure to notify Diatheke that no more audio will be coming when
# we are done writing data.
stream.finish()

      
// Get the audio data from a source. This could be a microphone, file, or
// any other source. Here we assume the audio data was retrieved previously
// and stored in a buffer.

// Push the audio data to the input stream. This function may be called
// multiple times.
stream.pushAudio(data: data)

// Be sure to notify Diatheke that no more audio will be coming when
// we are done writing data.
stream.finish()

      
byte[] bytes = ...;
ByteString byteString=ByteString.copyFrom(bytes);
DiathekeOuterClass.AudioInput audioInput = DiathekeOuterClass.AudioInput.newBuilder()
        .setSessionId(sessionId)
        .setData(byteString).build();
audioInputStreamObserver.onNext(audioInput);

      After all audio data has been pushed to the server, client code should be sure to call the Finish() method to notify Diatheke that no more audio will be coming.

      Transcriptions for session audio input are not returned as part of the audio input stream. They are returned as Recognize events on the session’s event stream.