Acefone

Overview

AcefoneFrameSerializer converts between Pipecat frames and the Acefone / Smartflo (Tata Tele Business) bi-directional audio streaming protocol, enabling real-time voice agents over a websocket. It is designed to be wired into a FastAPIWebsocketTransport so you can host a Pipecat agent on the Acefone/Smartflo telephony stack and reach it over an Indian phone number. It supports both ULAW (8kHz G.711 μ-law, the default) and PCM (16-bit linear PCM) wire formats, DTMF keypad input, interruptions, and optional automatic call termination over the same websocket.

Source Repository

Source code, examples, and issues for the Acefone/Smartflo integration

PyPI Package

The pipecat-acefone package on PyPI

Learn about Acefone / Smartflo telephony and get a phone number

Protocol Docs

Acefone/Smartflo bi-directional audio streaming message formats

Installation

This is a community-maintained package distributed separately from pipecat-ai:

pip install pipecat-acefone

Prerequisites

To host an agent on the Acefone/Smartflo telephony stack you need:

An Acefone or Smartflo phone number: with bi-directional audio streaming enabled and pointed at your bot’s websocket endpoint.
A public websocket endpoint: expose your bot’s websocket so Acefone/Smartflo can connect to it (for example, by tunneling with ngrok during development).

The serializer itself does not require any API keys — automatic hang-up is performed over the same websocket via an end event. The provider’s message formats are documented in the Acefone and Smartflo docs.

Configuration

AcefoneFrameSerializer takes a single, optional params argument:

AcefoneFrameSerializer.InputParams

default:"InputParams()"

Serializer input parameters, including the stream/call identifiers. See InputParams below.

InputParams

Passed via the params constructor argument using AcefoneFrameSerializer.InputParams(...).

Parameter	Type	Default	Description
`media_format`	`AcefoneMediaFormat`	`ULAW`	Wire audio format. `ULAW` = 8kHz G.711 μ-law; `PCM` = 16-bit linear PCM (`slin16`).
`acefone_sample_rate`	`int`	`8000`	Sample rate of the Acefone/Smartflo media stream (Hz).
`sample_rate`	`int`	`0`	Pipeline input sample rate override. When `0`, the rate is taken from the `StartFrame` during setup.
`stream_sid`	`str`	`None`	The Media Stream SID for the call. Typically parsed from the initial `start` message; captured automatically from it if unset.
`call_sid`	`str`	`None`	The associated Call SID. Required when `auto_hang_up` is enabled.
`auto_hang_up`	`bool`	`False`	Terminate the call via a websocket `end` event on the first `EndFrame`/`CancelFrame`.

See the source repository for the authoritative, up-to-date list of parameters and message formats.

Usage

Wire the serializer into a FastAPIWebsocketTransport. The stream_sid (and call_sid, if you enable auto hang-up) is read from the initial websocket start message Acefone/Smartflo sends when a call connects.

from pipecat_acefone import AcefoneFrameSerializer, AcefoneMediaFormat
from pipecat.transports.websocket.fastapi import (
    FastAPIWebsocketTransport,
    FastAPIWebsocketParams,
)

serializer = AcefoneFrameSerializer(
    AcefoneFrameSerializer.InputParams(
        stream_sid=stream_id,
        call_sid=call_id,
        auto_hang_up=True,
        media_format=AcefoneMediaFormat.ULAW,
    )
)

transport = FastAPIWebsocketTransport(
    websocket=websocket_client,
    params=FastAPIWebsocketParams(
        audio_in_enabled=True,
        audio_out_enabled=True,
        add_wav_header=False,
        serializer=serializer,
    ),
)

See the source repository for a complete bot.py example, including parsing stream_sid from the initial websocket messages and running the bot behind an ngrok tunnel.

Compatibility

Tested with Pipecat v1.5.0 and Python 3.11+. Check the source repository for the latest tested version and changelog.

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Acefone

Overview

Source Repository

PyPI Package

Acefone

Protocol Docs

Installation

Prerequisites

Configuration

InputParams

Usage

Compatibility

​Overview

Source Repository

PyPI Package

Acefone

Protocol Docs

​Installation

​Prerequisites

​Configuration

​InputParams

​Usage

​Compatibility

Overview

Installation

Prerequisites

Configuration

InputParams

Usage

Compatibility