Cobra Binding for Web

Cobra Voice Activity Detection Engine

Made in Vancouver, Canada by Picovoice

Cobra is a highly accurate and lightweight voice activity detection (VAD) engine.

Compatibility

• Chrome / Edge
• Firefox
• Safari

Restrictions

IndexedDB is required to use Cobra in a worker thread. Browsers without IndexedDB support (i.e. Firefox Incognito Mode) should use Cobra in the main thread.

Installation

Using yarn:

yarn add @picovoice/cobra-web

or using npm:

npm install --save @picovoice/cobra-web

AccessKey

Cobra requires a valid Picovoice AccessKey at initialization. AccessKey acts as your credentials when using Cobra SDKs. You can get your AccessKey for free. Make sure to keep your AccessKey secret. Signup or Login to Picovoice Console to get your AccessKey.

Usage

Initialization

Create a voiceProbabilityCallback function to get voice probability results from the engine:

function voiceProbabilityCallback(voiceProbability: number) {

}

Add a processErrorCallback function to the options object if you would like to catch errors that occur while processing audio:

function processErrorCallback(error: string) {

}

options.processErrorCallback = processErrorCallback;

Use Cobra to initialize the engine on the main thread:

const cobra = await Cobra.create(
    ${ACCESS_KEY},
    voiceProbabilityCallback,
    options
);

Use CobraWorker to initialize the engine on a worker thread:

const cobra = await CobraWorker.create(
  ${ACCESS_KEY},
  voiceProbabilityCallback,
  options
);

Process Audio

The process function will send the input frames to the engine. The engine results are received via the voiceProbabilityCallback that's passed in during initialization.

function getAudioData(): Int16Array {
  ... // function to get audio data
  return new Int16Array();
}

for (;;) {
  cobra.process(getAudioData());
  // break on some condition
}

Clean Up

Clean up used resources by Cobra or CobraWorker:

await cobra.release();

Terminate (Worker only)

Terminate CobraWorker instance:

await cobra.terminate();

Demo

For example usage refer to our Web demo application.