Vonage

OverviewCopy Anchor Link

VonageFrameSerializer speaks the WebSocket protocol of Vonage's Audio Connector, which streams a Vonage Video session's audio (or a Voice API call's) to your server:

• Binary messages carry raw 16-bit PCM (16 kHz by default), resampled to the pipeline's input rate as InputAudioRawFrames.
• Bot audio is resampled to the Vonage rate and sent as binary messages.
• JSON text events: websocket:connected, websocket:cleared and websocket:notify are logged, and websocket:dtmf becomes an InputDTMFFrame.
• An InterruptionFrame sends {"action": "clear"}.

InstallationCopy Anchor Link

bun add @pipedog/serializer-vonage @pipedog/transport-websocket

import { VonageFrameSerializer } from "@pipedog/serializer-vonage/vonage";

PrerequisitesCopy Anchor Link

• A Vonage application, and an Audio Connector (or a Voice API websocket endpoint) pointed at your WebSocket URL, with audio/l16 at the rate you configure.

VonageFrameSerializerCopy Anchor Link

ConfigurationCopy Anchor Link

InputParamsCopy Anchor Link

params is a VonageFrameSerializer.InputParams (VonageFrameSerializerInputParams):

UsageCopy Anchor Link

import { VonageFrameSerializer } from "@pipedog/serializer-vonage/vonage";
import {
  FastAPIWebsocketParams,
  FastAPIWebsocketTransport,
} from "@pipedog/transport-websocket/fastapi";
import { websocketFetchHandler } from "@pipedog/transport-websocket/fetch";
import type { WebsocketConnection } from "@pipedog/transport-websocket/socket";

async function runSession(connection: WebsocketConnection): Promise<void> {
  const serializer = new VonageFrameSerializer({
    // The rate you gave the Audio Connector (audio/l16;rate=16000).
    params: new VonageFrameSerializer.InputParams({ vonageSampleRate: 16000 }),
  });

  const transport = new FastAPIWebsocketTransport(
    connection,
    new FastAPIWebsocketParams({
      audioInEnabled: true,
      audioOutEnabled: true,
      addWavHeader: false,
      serializer,
    }),
  );
  // ... build and run the pipeline with transport.input() and transport.output()
}

// The Audio Connector's websocket.uri points here.
const handler = websocketFetchHandler(runSession);

NotesCopy Anchor Link

• DTMF digits may arrive as strings or numbers, under digit or dtmf.digit; both work.
• OutputTransportMessageFrames are sent as JSON text (e.g. a notify action), except RTVI messages while ignoreRtviMessages is on.
• There is no hang-up call: end the session from Vonage's side.

Runtime notesCopy Anchor Link

Generated from pipecat.runtimes and pipecat.compat in packages/serializer-vonage/package.json: ✅ means the compat smoke test passes on that runtime.

Runs on Bun, Node, Deno and Cloudflare Workers. The package's golden tests replay vectors recorded from upstream: at 16 kHz the audio is byte-identical.