Integrating AI Receptionist with Asterisk - ARI vs. AGI Approach

Hi, I’m working on a project to integrate an AI receptionist with my Asterisk server, and I’m looking for some guidance on the approach.

Use Case:

I have an AI dental receptionist application developed in Python. It uses asyncio for asynchronous operations. The application handles:

  • Speech-to-Text (STT): Transcribes audio input.
  • AI Response Generation: Uses an LLM (specifically Groq’s LLaMA model) to generate responses.
  • Text-to-Speech (TTS): Converts AI responses to speech.
  • Audio Management: Manages real-time audio playback and cleanup.

The main goal is for callers to interact with this AI receptionist when they call my Twilio number that’s connected to my Asterisk server.

What I’ve Tried:

  1. Using ARI (Asterisk REST Interface):
  • I attempted to use ARI to create an ExternalMedia channel that connects Asterisk to my AI application.
  • I followed the documentation and set up an ARI application in Python.
  • Faced compatibility issues with the ARI Python libraries. Libraries like ari and asterisk-ari seemed outdated or incompatible with Python 3. Also tried using forks that are Python 3 compatible.
  • Tried using asyncari, which aligns with my application’s use of asyncio, but encountered compatibility and implementation challenges.
  1. Adjusting AI Application for RTP Streams:
  • My AI application currently uses raw UDP sockets for audio input/output.
  • Adjusting it to handle RTP streams required significant changes, and I ran into complexities with RTP handling and synchronization.

Considering an AGI Approach:

Given the challenges with ARI, I’m thinking about using AGI instead. My idea is to have an AGI script that minimally interacts with Asterisk and delegates all processing to my AI application.

Questions:

  1. Is AGI a viable approach for my use case?
  2. Are there better ways to handle audio streaming between Asterisk and an external application without dealing with RTP complexities?
  3. Has anyone successfully integrated a similar AI application with Asterisk? If so, what approach did you use?
  4. Any recommendations on Python libraries or methods to handle RTP streams more easily, or is there a way to simplify this integration?

Additional Details:

  • My Asterisk server is running on Debian, and I’m using Asterisk certified version 20.7.
  • The AI application is currently designed to work with local audio devices but has been adapted to receive and send audio over UDP sockets.
  • I’m aiming for minimal changes to both Asterisk configurations and my AI codebase.

I appreciate any insights or advice anyone has to offer and happy to clarify anything further.

Thank you for your time!

hmm, this is what the Chat GPT AI said to do - ya sure you think doing this is a good idea after reading this? Just asking! LOL

Integrating AI into Asterisk, an open-source PBX (Private Branch Exchange) software, can provide advanced features such as voice recognition, automated call handling, natural language processing (NLP), and more. Here’s a step-by-step guide to integrating AI into Asterisk:

1. Set Up Asterisk

  • Install Asterisk: Ensure Asterisk is properly installed on your server. You can find installation instructions on the Asterisk website.
  • Configure Extensions and Dialplans: Set up basic dialplans to route calls.

2. Identify AI Use Cases

Depending on your needs, the AI can be used in various ways within Asterisk. Some examples include:

  • Speech Recognition: Convert spoken language to text to interact with automated systems.
  • Text-to-Speech (TTS): Convert text data into speech to respond to users.
  • Call Routing & Automation: Use NLP to route calls intelligently or provide virtual assistants.
  • Chatbots: Combine with AI chatbots for multi-channel support (voice, text).
  • Sentiment Analysis: Analyze customer sentiment during calls for better handling.

3. Choose AI Technologies

  • Speech Recognition and NLP: Tools like Google Speech-to-Text, Wit.ai, or Microsoft Azure Cognitive Services can help transcribe calls and interact in natural language.
  • Text-to-Speech (TTS): Solutions like Google Cloud TTS, Amazon Polly, or open-source tools like Festival can convert text to speech.
  • Custom AI Models: If you have specific needs, consider creating custom machine learning models using TensorFlow, PyTorch, or OpenAI’s GPT models for conversational AI.

4. Use Asterisk APIs or Dialplan Functions

Asterisk has several methods for integrating external systems, including its AMI (Asterisk Manager Interface), AGI (Asterisk Gateway Interface), and ARI (Asterisk REST Interface). Choose one depending on your integration needs:

  • AMI: Allows you to control Asterisk from an external system. This is useful for monitoring and managing call flow.
  • AGI: A script-based interface where you can run external programs (e.g., a Python script for AI). You can use AGI to invoke AI-based services like speech recognition.
  • ARI: A modern REST API to interface directly with Asterisk. This is useful for more complex integrations and allows you to manage calls and endpoints dynamically.

5. Integrating AI with Asterisk

Using AGI (Asterisk Gateway Interface) with Python

  1. Install Python and Dependencies:
  • Make sure Python is installed on your server.
  • Install libraries like speech_recognition, requests, or twilio for API integration.
  1. Create a Python AGI Script: You can use an AGI script to interact with Asterisk. Here’s an example of using Python for speech recognition:

python

Copy code

# speech_agi.py
from asterisk.agi import AGI
import speech_recognition as sr

agi = AGI()
agi.verbose("Starting speech recognition")

# Capture audio from the call (assuming audio is being recorded)
audio_file = "/tmp/audio.wav"
agi.stream_file('beep')  # Play beep sound before listening
agi.record_file(audio_file, "wav", 300, "#")  # Record 5 minutes, # to stop recording

# Initialize speech recognizer
recognizer = sr.Recognizer()

with sr.AudioFile(audio_file) as source:
    audio = recognizer.record(source)

try:
    # Convert audio to text
    text = recognizer.recognize_google(audio)
    agi.verbose(f"Recognized text: {text}")
    agi.say(text)  # Respond with recognized text
except Exception as e:
    agi.verbose(f"Error: {str(e)}")
    agi.say("Sorry, I could not understand.")
  • In the example above, Asterisk calls the AGI script, records audio, then uses Google’s Speech-to-Text API to transcribe speech into text and respond.
  1. Configure Asterisk Dialplan to Use AGI: You need to define the AGI script in your Asterisk dialplan. Modify extensions.conf:

bash

Copy code

[default]
exten => 1234,1,Answer()
exten => 1234,n,AGI(speech_agi.py)
exten => 1234,n,Hangup()

Using Speech APIs for Integration

  1. Google Cloud Speech-to-Text API: You can use Google’s API for speech recognition. To integrate it, use an AGI script to send audio to Google’s API and get text in return.
  2. Text-to-Speech API: You can integrate Text-to-Speech (TTS) for AI responses. For example, use Google TTS or Amazon Polly in an AGI script to generate speech.

6. Configure Asterisk for Real-Time Interaction

  • Ensure that Asterisk is configured to allow real-time interaction with AI. For example, use Asterisk ARI for advanced applications where you need more complex interactions with real-time call data.

7. Testing and Optimization

  • Test your AI integrations: Test the AI responses in different scenarios to ensure the system is responding as expected.
  • Optimize Performance: Optimize the speech recognition process to minimize latency. Consider using local servers for speech processing if response time is critical.

Example of a Full AI-based IVR system

  • AI for IVR (Interactive Voice Response): You can set up an AI-based IVR using voice recognition and NLP. For instance, when a caller reaches your IVR, they can say things like “I need technical support” or “Check account balance.” Your AI will process the command and route the call accordingly.
  • This can be integrated by using a combination of AGI, a third-party speech recognition service (like Google Cloud Speech), and a machine learning model for intent recognition.

8. Use External AI Platforms

  • Dialogflow (Google): Integrate Dialogflow with Asterisk using webhooks or API calls for conversational agents.
  • Rasa AI: You can host a Rasa instance and call it from Asterisk via HTTP or AGI, creating conversational AI for call routing or responses.

Conclusion

Integrating AI into Asterisk requires a combination of Asterisk’s flexible API system (such as AGI, AMI, or ARI) and external AI services like speech recognition, text-to-speech, or NLP platforms. You can automate and enhance customer interactions through intelligent voice handling, creating a more dynamic and responsive system.

Let me know if you need any more specific details about setting this up!

1 Like

Hi dannyb,

Did you consider using the Asterisk AudioSocket application?
I suggest taking a look at this video: https://youtu.be/kayBTMsQfto?si=yCsS7ska71H8J52z.
It’s in Italian, but if you need any help understanding it, feel free to ask—I’d be happy to assist.

Regards,
Giuseppe

2 Likes

Here’s my current list of options for Python API wrappers, and the features they support:

Name AMI AGI ARI asyncio TLS
pyst2 yes yes no no (uses threads) no
py-asterisk yes no no no no
panoramisk yes FastAGI only no yes no
asyncari no no yes via anyio no
seaskirt yes yes yes yes yes

Of course that last one is mine.

1 Like