Porcupine Wake Word
Node.js API

API Reference for the Node.js Porcupine SDK (npmjs).

Porcupine

class Porcupine

Class for the Porcupine wake word engine. Porcupine can be initialized using the class constructor(). Resources should be cleaned when you are done using the release() method.

Porcupine.constructor()

Porcupine.constructor(
  accessKey,
  keywords,
  sensitivities,
  options: PorcupineOptions = {}
)

constructor method for Porcupine wake word engine.

Parameters

• accessKey string : AccessKey obtained from Picovoice Console.
• keywords Array<string> : Absolute paths to keyword model files.
• sensitivities Array<number> : Sensitivities for detecting keywords. Each value should be a number within [0, 1]. A higher sensitivity results in fewer misses at the cost of increasing the false alarm rate.
• options PorcupineOptions : Optional init configuration arguments:
  • modelPath string : Path to the file containing model parameters (.pv).
  • device string : String representation of the device (e.g., CPU or GPU) to use. If set to best, the most suitable device is selected automatically. If set to gpu, the engine uses the first available GPU device. To select a specific GPU device, set this argument to gpu:${GPU_INDEX}, where ${GPU_INDEX} is the index of the target GPU. If set to cpu, the engine will run on the CPU with the default number of threads. To specify the number of threads, set this argument to cpu:${NUM_THREADS}, where ${NUM_THREADS} is the desired number of threads.
  • libraryPath string : Path to the Orca dynamic library (.node).

Returns

• Porcupine: An instance of Porcupine wake word engine.

Porcupine.listAvailableDevices()

static listAvailableDevices(options: PorcupineInputOptions = {}): string[]

Lists all available devices that Porcupine can use for inference. Each entry in the list can be the device argument of the constructor.

Parameters

• options PorcupineInputOptions : Optional input configuration arguments:
  • libraryPath string : Path to the Porcupine dynamic library (.node).

Returns

• string[] : List of all available devices that Porcupine can use for inference.

Porcupine.process()

process(frame: Int16Array): number

Processes a frame of the incoming audio stream and emits the detection result. The number of samples per frame can be attained by calling .frameLength. The incoming audio needs to have a sample rate equal to .sampleRate and be 16-bit linearly-encoded. Porcupine operates on single-channel audio.

Parameters

• frame Array<number> : A frame of audio samples.

Returns

• number : Index of observed keyword at the end of the current frame. Indexing is 0-based and matches the ordering of keyword models provided to the constructor. If no keyword is detected then it returns -1.

Porcupine.frameLength

get frameLength(): number

The number of audio samples per frame.

Porcupine.sampleRate

get sampleRate(): number

The audio sample rate accepted by the Porcupine engine.

Porcupine.version

get version(): string

The version of the Porcupine engine.

Porcupine.release()

release(): void

Releases resources acquired by Porcupine

PorcupineOptions

type PorcupineOptions = {
  modelPath?: string;
  device?: string;
  libraryPath?: string;
};

Porcupine init options type.

• modelPath string : The path to the Porcupine model (.pv).
• device string? : String representation of the device (e.g., CPU or GPU) to use for inference. If set to best, picoLLM picks the most suitable device. If set to gpu, the engine uses the first available GPU device. To select a specific GPU device, set this argument to gpu:${GPU_INDEX}, where ${GPU_INDEX} is the index of the target GPU. If set to cpu, the engine will run on the CPU with the default number of threads. To specify the number of threads, set this argument to cpu:${NUM_THREADS}, where ${NUM_THREADS} is the desired number of threads.
• libraryPath string : The path to the Porcupine dynamic library.

PorcupineInputOptions

type PorcupineInputOptions = {
  libraryPath?: string;
};

Porcupine input options type.

• libraryPath string : The path to the Porcupine dynamic library.

BuiltInKeyword

enum BuiltInKeyword {
  ALEXA = "alexa",
  AMERICANO = "americano",
  BLUEBERRY = "blueberry",
  BUMBLEBEE = "bumblebee",
  COMPUTER = "computer",
  GRAPEFRUIT = "grapefruit",
  GRASSHOPPER = "grasshopper",
  HEY_GOOGLE = "hey google",
  HEY_SIRI = "hey siri",
  JARVIS = "jarvis",
  OK_GOOGLE = "ok google",
  PICOVOICE = "picovoice",
  PORCUPINE = "porcupine",
  TERMINATOR = "terminator",
}

Enum of built-in keywords.

Errors

Exceptions thrown if an error occurs within Porcupine Wake Word engine.

Exceptions:

class PvStatusOutOfMemoryError        extends Error {}
class PvStatusIoError                 extends Error {}
class PvStatusInvalidArgumentError    extends Error {}
class PvStatusStopIterationError      extends Error {}
class PvStatusKeyError                extends Error {}
class PvStatusInvalidStateError       extends Error {}
class PvStatusRuntimeError            extends Error {}
class PvStatusActivationError         extends Error {}
class PvStatusActivationLimitReached  extends Error {}
class PvStatusActivationThrottled     extends Error {}
class PvStatusActivationRefused       extends Error {}