Realtime Networked TCP Vocoder

Project Overview

This project is a real-time vocoder audio processing system that enables voice transformation through multiple audio effects. It features a client-server architecture for networked audio transmission and remote control of effects. The system can process microphone input in real-time, apply various voice modulation effects, and stream the processed audio either locally or through a network.

Key Features

• Multiple Audio Effects:

  • Low Effect: Pitch shifting down for a deeper voice
  • High Effect: Pitch shifting up for a higher voice
  • Pitch Effect: Customizable pitch shifting with variable rate
  • Wobble Effect: Amplitude modulation for a tremolo-like sound
  • Robot Effect: Carrier wave modulation for a mechanical voice
  • Echo Effect: Delay with feedback for echo/reverb effects

• Network Capabilities:

  • Stream processed audio over TCP/IP
  • Remote control of effects via network commands
  • Separate control and audio streaming channels

Team Contributions

Team Member Contributions:

• Aashvi:

  • TCP networking + connections
  • Sender/Receiver architecture
  • Raspberry Pi set-up
  • Effect creation (pitch change/robot)

• Ronit:

  • Makefile creation / repo organization
  • Input parsing and processing
  • Audio streaming and buffer handling
  • Error handling and logging

• Sneha:

  • TCP networking + connections
  • Audio buffer handling
  • Multithreading
  • Effects creation (wobble/echo)

Installation

Prerequisites

• GCC compiler (or compatible C compiler)
• POSIX-compatible operating system (Linux/macOS)
• PortAudio library
• ALSA audio library (for Linux)
• pthread support

Dependencies Installation

Ubuntu/Debian:

sudo apt update
sudo apt install build-essential libportaudio2 libportaudio-dev libasound2-dev

macOS:

brew install portaudio

Building the Project

1. Clone the repository:

git clone https://github.com/your-username/realtime-networked-vocoder.git
cd realtime-networked-vocoder

2. Compile the project:

Receiver -

make

This will build the main vocoder application and receiver/sender components.

Usage

Network Mode

Receiver (Audio Output Device):

./receiver

Start this on the machine where you want audio playback.

Sender (Audio Input Device):

./sender <receiver_ip>

Start this on the machine with the microphone input, replacing <receiver_ip> with the IP address of the receiver machine.

Effect Control

When running the sender, you'll see a command prompt where you can type effect names:

Effect > none    # No effect
Effect > low     # Lower pitch effect
Effect > high    # Higher pitch effect
Effect > pitch 1.5  # Custom pitch
Effect > wobble  # Amplitude modulation effect
Effect > robot   # Robotic voice effect
Effect > echo    # Echo effect

Future Improvements

• Reduce latency
• Implement security features
• Add graphical user interface with real-time visualization of audio waves

Acknowledgements

We would like to thank the 341 Honors course staff, especially our mentor Mark Kraay for guiding us and helping us idealize our vision for our project.