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

Requirements

Cobra Web Binding uses SharedArrayBuffer
for processing speaker diarization.

Include the following headers in the response to enable the use of SharedArrayBuffers:

``
Cross-Origin-Opener-Policy: same-origin
Cross-Origin-Embedder-Policy: require-corp
`

Refer to our Web demo for an example on creating a server with the corresponding response headers.

Browsers that lack support for SharedArrayBuffers or required headers will fall back to using standard ArrayBuffers,
which disables multithreaded performance.

$3

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.

Multi-threading is only enabled for Cobra when using on a web worker.

Installation

Using yarn:

`console
yarn add @picovoice/cobra-web
`

or using npm:

`console
npm install --save @picovoice/cobra-web
`

$3

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.

$3

#### Initialization

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

`typescript

function voiceProbabilityCallback(voiceProbability: number) {

}
`

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

`typescript
function processErrorCallback(error: string) {

}

options.processErrorCallback = processErrorCallback;
`

Use Cobra to initialize the engine on the main thread:

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

Use CobraWorker to initialize the engine on a worker thread:

`typescript
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.

`typescript
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:

`typescript
await cobra.release();
`

#### Terminate (Worker only)

Terminate CobraWorker instance:

`typescript
await cobra.terminate();
``

Demo

For example usage refer to our Web demo application.