Falcon Binding for Web

Falcon Speaker Diarization Engine

Made in Vancouver, Canada by Picovoice

Falcon is an on-device speaker diarization engine. Falcon is:

• Private; All voice processing runs locally.
• Cross-Platform:
  • Linux (x86_64), macOS (x86_64, arm64), Windows (x86_64)
  • Raspberry Pi (4, 3) and NVIDIA Jetson Nano
  • Chrome, Safari, Firefox, and Edge

Compatibility

• Chrome / Edge
• Firefox
• Safari

Restrictions

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

Installation

Using yarn:

yarn add @picovoice/falcon-web

or using npm:

npm install --save @picovoice/falcon-web

AccessKey

Falcon requires a valid Picovoice AccessKey at initialization. AccessKey acts as your credentials when using Falcon 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

For the web packages, there are two methods to initialize Falcon.

Public Directory

NOTE: Due to modern browser limitations of using a file URL, this method does not work if used without hosting a server.

This method fetches the model file from the public directory and feeds it to Falcon. Copy the model file into the public directory:

cp ${FALCON_MODEL_FILE} ${PATH_TO_PUBLIC_DIRECTORY}

Base64

NOTE: This method works without hosting a server, but increases the size of the model file roughly by 33%.

This method uses a base64 string of the model file and feeds it to Falcon. Use the built-in script pvbase64 to base64 your model file:

npx pvbase64 -i ${FALCON_MODEL_FILE} -o ${OUTPUT_DIRECTORY}/${MODEL_NAME}.js

The output will be a js file which you can import into any file of your project. For detailed information about pvbase64, run:

npx pvbase64 -h

Language Model

Falcon saves and caches your model file in IndexedDB to be used by WebAssembly. Use a different customWritePath variable to hold multiple models and set the forceWrite value to true to force re-save a model file.

Either base64 or publicPath must be set to instantiate Falcon. If both are set, Falcon will use the base64 model.

const falconModel = {
  publicPath: ${MODEL_RELATIVE_PATH},
  // or
  base64: ${MODEL_BASE64_STRING},

  // Optionals
  customWritePath: "falcon_model",
  forceWrite: false,
  version: 1,
}

Initialize Falcon

Create an instance of Falcon in the main thread:

const falcon = await Falcon.create(
  "${ACCESS_KEY}",
  falconModel
);

Or create an instance of Falcon in a worker thread:

const falcon = await FalconWorker.create(
  "${ACCESS_KEY}",
  falconModel
);

Process Audio Frames

The process result is an object with:

• segments: A list of objects containing a startSec, endSec, and speakerTag.
  • startSec: Indicates when the segment started. Value is in seconds.
  • endSec: Indicates when the segment ended. Value is in seconds.
  • speakerTag: A non-negative integer identifying unique speakers, with 0 reserved for unknown speakers.

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

const result = await falcon.process(getAudioData());
console.log(result.segments);

For processing using worker, you may consider transferring the buffer instead for performance:

let pcm = new Int16Array();
const result = await falcon.process(pcm, {
  transfer: true,
  transferCallback: (data) => { pcm = data }
});
console.log(result.segments);

Clean Up

Clean up used resources by Falcon or FalconWorker:

await falcon.release();

Terminate FalconWorker instance:

await falcon.terminate();

Demo

For example usage refer to our Web demo application.