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Cobra Voice Activity Detection
Node.js API

API Reference for the Node.js Cobra SDK (npm)


Cobra

class Cobra { }

Class for the Cobra Voice Activity Detection engine.

Cobra can be initialized using the class constructor(). Resources should be cleaned when you are done using the release() method.


Cobra.constructor()

Cobra.constructor(
accessKey: string,
options: CobraOptions = {}
)

Cobra constructor.

Parameters

  • accessKey string : AccessKey obtained from Picovoice Console.
  • options CobraOptions: Optional configuration arguments:
    • libraryPath string : Path to the Cobra dynamic library (.node).

Returns

  • Cobra: An instance of Cobra platform.

Cobra.release()

Cobra.release()

Releases resources acquired by Cobra.


Cobra.frameLength

Cobra.frameLength

Getter for number of audio samples per frame.

Returns

  • number: Number of audio samples per frame.

Cobra.sampleRate

Cobra.sampleRate()

Getter for audio sample rate accepted by Cobra.

Returns

  • number: Audio sample rate accepted by Cobra.

Cobra.version

Cobra.version()

Getter for version.

Returns

  • string: Current Cobra version.

Cobra.process()

Cobra.process(pcm)

Processes a frame of the incoming audio stream with the voice activity detection engine. 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. Cobra operates on single-channel audio.

Parameters

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

Returns

  • number: Probability of voice activity. It is a floating-point number within [0, 1].

Errors

Exceptions thrown if an error occurs within Cobra Voice Activity Detection 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 {}

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Cobra Voice Activity Detection Node.js API
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