Voice Processor
Flutter API

API Reference for the Voice Processor Flutter SDK(pub.dev).

VoiceProcessor

class VoiceProcessor { }

Class for capturing audio and delivering frames to registered frame listeners.

VoiceProcessor.instance

static VoiceProcessor? get instance

Singleton instance of the VoiceProcessor class.

Returns

• VoiceProcessor? : The singleton instance of VoiceProcessor.

VoiceProcessor.numFrameListeners

int get numFrameListeners

Gets the number of registered frame listeners.

Returns

• int : The number of registered frame listeners.

VoiceProcessor.numErrorListeners

int get numErrorListeners

Gets the number of registered error listeners.

Returns

• int : The number of registered error listeners.

VoiceProcessor.addFrameListener()

void addFrameListener(VoiceProcessorFrameListener listener)

Adds a new listener that receives audio frames.

Parameters

• listener VoiceProcessorFrameListener : Listener function that executes user code on a frame of audio.

VoiceProcessor.addFrameListeners()

void addFrameListeners(List<VoiceProcessorFrameListener> listeners)

Adds a list of listeners that receive audio frames.

Parameters

• listeners List<VoiceProcessorFrameListener> : List of listener functions that execute user code on frames of audio.

VoiceProcessor.removeFrameListener()

void removeFrameListener(VoiceProcessorFrameListener listener)

Removes a previously added frame listener.

Parameters

• listener VoiceProcessorFrameListener : The listener function to be removed.

VoiceProcessor.removeFrameListeners()

void removeFrameListeners(List<VoiceProcessorFrameListener> listeners)

Removes previously added frame listeners.

Parameters

• listeners List<VoiceProcessorFrameListener> : List of listener functions to be removed.

VoiceProcessor.clearFrameListeners()

void clearFrameListeners()

Removes all frame listeners.

VoiceProcessor.addErrorListener()

void addErrorListener(VoiceProcessorErrorListener errorListener)

Adds a new error listener.

Parameters

• errorListener VoiceProcessorErrorListener : Listener function that handles errors.

VoiceProcessor.removeErrorListener()

void removeErrorListener(VoiceProcessorErrorListener errorListener)

Removes a previously added error listener.

Parameters

• errorListener VoiceProcessorErrorListener : The error listener function to be removed.

VoiceProcessor.clearErrorListeners()

void clearErrorListeners()

Removes all error listeners.

VoiceProcessor.start()

Future<void> start(int frameLength, int sampleRate)

Starts audio recording with the given sampleRate and delivering audio frames of size frameLength to registered frame listeners.

Parameters

• frameLength int : Number of audio samples per frame to be delivered via the listeners.
• sampleRate int : Audio sample rate of the recorded audio.

Throws

• VoiceProcessorException : If an error occurs while attempting to start audio capture.

Returns

• Future<void> : A future that resolves when audio recording starts.

VoiceProcessor.stop()

Future<void> stop()

Stops audio recording.

Throws

• VoiceProcessorException : If an error occurs while attempting to stop audio capture.

Returns

• Future<void> : A future that resolves when audio recording stops.

VoiceProcessor.isRecording()

Future<bool?> isRecording()

Checks if audio recording is currently in progress.

Returns

• Future<bool?> : A future that resolves with a boolean indicating whether recording is active or not.

VoiceProcessor.hasRecordAudioPermission()

Future<bool?> hasRecordAudioPermission()

Checks if the app has permission to record audio and prompts the user if not.

Returns

• Future<bool?> : A future that resolves with a boolean indicating whether the application has permission to record audio or not.

VoiceProcessorFrameListener

typedef void VoiceProcessorFrameListener(List<int> frame);

Listener type for receiving audio frames from the VoiceProcessor.

VoiceProcessorErrorListener

typedef void VoiceProcessorErrorListener(VoiceProcessorException error);

Listener type for receiving errors from the VoiceProcessor.

VoiceProcessorException

class VoiceProcessorException implements Exception {
  final String? message;

  VoiceProcessorException([this.message]);
}

Exception class for errors related to the VoiceProcessor.