A lightweight, peer-to-peer voice communication application for local networks. LanVoice enables real-time audio streaming between two computers using UDP sockets.

• Real-time voice transmission over LAN
• Low latency audio streaming using UDP protocol
• Configurable remote address and ports
• Minimal dependencies (Java standard library only)
• Simple command-line interface

• Special thanks to WhatsApp Desktop for making their call functionality so remarkably terrible that it inspired the creation of this project.
• Heartfelt gratitude to my little brother for suggesting I build something like this so we could finally stop relying on WhatsApp Desktop for voice calls.

• Java 8 or higher
• Two computers connected to the same local network (or localhost for testing)

LanVoice captures audio from your microphone, splits it into small packets, and sends them via UDP to a remote address. Simultaneously, it listens for incoming audio packets and plays them through your speakers.

• Audio.java - Handles microphone input and speaker output using javax.sound.sampled
• UDPClient.java - Captures and sends audio packets to the remote peer
• UDPServer.java - Receives incoming audio packets and plays them
• Main.java - Entry point, parses arguments and coordinates components

java -jar LanVoice.jar

This will use default values:

• Remote address: localhost
• Remote port: 50005
• Local port: 50005

java -jar LanVoice.jar [remoteAddress] [remotePort] [localPort]

Computer A (IP: 192.168.1.10):

java -jar LanVoice.jar 192.168.1.20 50005 50005

Computer B (IP: 192.168.1.20):

java -jar LanVoice.jar 192.168.1.10 50005 50005

java -jar LanVoice.jar --help

Compile all Java files and create a JAR:

javac -d out src/*.java
jar cfe LanVoice.jar Main -C out .

• No audio? Make sure your microphone and speakers are properly configured in your OS settings.
• High latency? Try reducing the BUFFER_DURATION_MS value in Audio.java (lower values = less latency but more packets).
• Connection issues? Verify both computers are on the same network and firewalls allow UDP traffic on the specified ports.

• No encryption (not recommended for sensitive communications)
• No NAT traversal (requires direct network connectivity)
• Two peers only (no group calls)

This project is open source. Feel free to use and modify it.