How to get On-Device Speech Recognition to work continuously?

Hello,

I am unable to get my on-device speech recognition to work continuously. I know there is a 1 minute limit for Server based recognition but recent advances revealed in WWDC 2019 show that there is no limit for on-device recognition. Link below is the WWDC 2019 video on this.

Can anyone tell me what's wrong with my code or what I need to do to make it continuous? It is stopping the audio engine once transcription is done. But I dont want it to do so. Even if I by pass stopping the audio engine stop, it is still not recognizing and transcribing anymore speech. Look forward to some insight or recommendations. Thank-you!!!

https://developer.apple.com/videos/play/wwdc2019/256/

private func startRecording() throws {

// Cancel the previous task if it's running.

recognitionTask?.cancel()

self.recognitionTask = nil

// Configure the audio session for the app.

let audioSession = AVAudioSession.sharedInstance()

try audioSession.setCategory(.record, mode: .measurement, options: .duckOthers)

try audioSession.setActive(true, options: .notifyOthersOnDeactivation)

let inputNode = audioEngine.inputNode

// Create and configure the speech recognition request.

recognitionRequest = SFSpeechAudioBufferRecognitionRequest()

guard let recognitionRequest = recognitionRequest else { fatalError("Unable to create a SFSpeechAudioBufferRecognitionRequest object") }

recognitionRequest.shouldReportPartialResults = true

// Keep speech recognition data on device

if #available(iOS 13, *) {

recognitionRequest.requiresOnDeviceRecognition = false

}

// Create a recognition task for the speech recognition session.

// Keep a reference to the task so that it can be canceled.

recognitionTask = speechRecognizer.recognitionTask(with: recognitionRequest) { result, error in

var isFinal = false

if let result = result {

// Update the text view with the results.

self.textView.text = result.bestTranscription.formattedString

isFinal = result.isFinal

print("Text \(result.bestTranscription.formattedString)")

}

if error != nil || isFinal {

// Stop recognizing speech if there is a problem.

self.audioEngine.stop()

inputNode.removeTap(onBus: 0)

self.recognitionRequest = nil

self.recognitionTask = nil

self.recordButton.isEnabled = true

self.recordButton.setTitle("Start Journaling", for: [])

}

}

// Configure the microphone input.

let recordingFormat = inputNode.outputFormat(forBus: 0)

inputNode.installTap(onBus: 0, bufferSize: 1024, format: recordingFormat) { (buffer: AVAudioPCMBuffer, when: AVAudioTime) in

self.recognitionRequest?.append(buffer)

}

audioEngine.prepare()

try audioEngine.start()

// Let the user know to start talking.

textView.text = "(Go ahead, I'm listening)"

}