Cheetah Speech-to-Text
React Native API

API Reference for the React Native Cheetah SDK (npm)

Cheetah

class Cheetah { }

Class for the Cheetah Speech-to-Text engine.

Cheetah.create()

public static async create(
  accessKey: string,
  modelPath: string,
  options: CheetahOptions = {}
): Promise<Cheetah>

Cheetah constructor.

Parameters

• accessKey string : AccessKey obtained from Picovoice Console.
• modelPath string : Path to the file containing model parameters (.pv). Can be relative to the assets/resource folder or an absolute path to the file on device.
• options CheetahOptions: Optional configuration arguments:
  • endpointDuration number : Duration of endpoint in seconds. A speech endpoint is detected when there is a chunk of audio (with a duration specified herein) after an utterance without any speech in it. Set duration to 0 to disable this. Default is 1 second.
  • enableAutomaticPunctuation boolean : Whether to enable automatic punctuation.

Returns

• Promise<Cheetah>: An instance of Cheetah platform.

Cheetah.delete()

async delete()

Releases resources acquired by Cheetah.

Cheetah.frameLength

get frameLength()

Getter for number of audio samples per frame.

Returns

• number: Number of audio samples per frame.

Cheetah.sampleRate

get sampleRate()

Getter for audio sample rate accepted by Cheetah.

Returns

• number: Audio sample rate accepted by Cheetah.

Cheetah.version

get version()

Getter for version.

Returns

• string: Current Cheetah version.

Cheetah.process()

async process(frame: number[]): Promise<CheetahTranscript>

Processes a frame of the incoming audio stream with the speech-to-text 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. Cheetah operates on single-channel audio.

Parameters

• frame number[] : A frame of audio samples.

Returns

• Promise<CheetahTranscript>: A CheetahTranscript object that contains any newly-transcribed speech (if none is available then an empty string is returned) and a flag indicating if an endpoint has been detected.

Cheetah.flush()

async flush(): Promise<CheetahTrancript>

Marks the end of the audio stream, flushes internal state of the object, and returns any remaining transcribed text.

Returns

• Promise<CheetahTranscript>: Any remaining transcribed text in a CheetahTranscript object. If none is available then an empty string is returned.

CheetahError

class CheetahError extends Error { }

Exception thrown if an error occurs within Cheetah Speech-to-Text engine.

Exceptions:

class CheetahActivationError           extends CheetahError { }
class CheetahActivationLimitError      extends CheetahError { }
class CheetahActivationRefusedError    extends CheetahError { }
class CheetahActivationThrottledError  extends CheetahError { }
class CheetahIOError                   extends CheetahError { }
class CheetahInvalidArgumentError      extends CheetahError { }
class CheetahInvalidStateError         extends CheetahError { }
class CheetahKeyError                  extends CheetahError { }
class CheetahMemoryError               extends CheetahError { }
class CheetahRuntimeError              extends CheetahError { }
class CheetahStopIterationError        extends CheetahError { }

CheetahOptions

type CheetahOptions = {
  endpointDurationSec?: number
  enableAutomaticPunctuation?: boolean;
}

Cheetah options type.

• endpointDurationSec number : Duration of endpoint in seconds. A speech endpoint is detected when there is a chunk of audio (with a duration specified herein) after an utterance without any speech in it. Set to 0 to disable endpoint detection.
• enableAutomaticPunctuation boolean : Flag to enable automatic punctuation insertion.

CheetahTranscript

type CheetahTranscript = {
    transcript: string;
    isEndpoint: boolean;
}

Cheetah options type.

• transcript string : Any newly-transcribed speech. If none is available then an empty string is returned.
• isEndpoint boolean : Flag indicating if an endpoint has been detected.