WRecorder

WRecorder provides multi-camera streaming between machines using OpenCV + ZeroMQ.

Active files

• Multi-stream scripts: camera_streamer.py, camera_receiver.py
• Startup scripts: launch1.sh, launch2.sh
• Required runtime defaults: argument_defaults.json
• Legacy documentation: OLD.md

Runtime defaults (required)

Both scripts require argument_defaults.json at runtime.

• Sections: both, streamer-only, receiver-only
• Behavior: missing/invalid file causes fail-fast startup error.
• Behavior: unknown keys or missing required keys also cause fail-fast startup error.
• Precedence: CLI flags override values from argument_defaults.json.

Prerequisites

• Python 3.7+
• Streamer packages:

python3 -m pip install opencv-python-headless pyzmq

• Receiver packages:

python3 -m pip install opencv-python pyzmq

Quick start

Start streamer:

python3 camera_streamer.py

Start receiver:

python3 camera_receiver.py

Use discovery by default (announce_discovery=on, auto_config=on in defaults file) or override per run with CLI flags.

Camera streamer arguments

Current CLI flags for camera_streamer.py:

• --base-port: Starting port for first camera stream; additional streams use base-port + index. Current default from argument_defaults.json: 5555.
• --camera-ids: Space-separated camera IDs (example: --camera-ids 0 2 4). Current default from argument_defaults.json: [0].
• --auto-find-cameras: on|off; auto-detect cameras and override --camera-ids. Current default from argument_defaults.json: on.
• --jpg-quality: JPEG quality in range 1-100. Current default from argument_defaults.json: 20.
• --target-fps: Target stream FPS, must be >= 1. Current default from argument_defaults.json: 30.
• --simulate-cameras: Simulate N cameras instead of real devices (must be >= 1). Current default from argument_defaults.json: null (disabled).
• --streamer-name: Discovery identity name for receiver filtering. Current default from argument_defaults.json: wrecorder-streamer.
• --announce-discovery: on|off; broadcast discovery metadata. Current default from argument_defaults.json: on.
• --discovery-port: UDP discovery port, valid range 1-65535. Current default from argument_defaults.json: 5550.
• --discovery-interval: Seconds between discovery packets. Current default from argument_defaults.json: 1.0.

Camera receiver arguments

Current CLI flags for camera_receiver.py:

• --broadcast-ip: Publisher IP address. Current default from argument_defaults.json: 0.0.0.0.
• --base-port: Starting port for first subscribed stream; additional streams use base-port + index. Current default from argument_defaults.json: 5555.
• --count: Number of sequential ports to subscribe to, starting at base-port. Current default from argument_defaults.json: 1.
• --show-stats: on|off; show per-stream stats overlay. Current default from argument_defaults.json: off.
• --timeout: Total setup timeout in seconds (discovery + initial connection). Current default from argument_defaults.json: 10.0.
• --auto-config: on|off; auto-configure from discovery announcements. Current default from argument_defaults.json: on.
• --streamer-name-filter: Accept only matching streamer name from discovery. Current default from argument_defaults.json: null (no filter).
• --discovery-port: UDP discovery port. Current default from argument_defaults.json: 5550.
• --discovery-timeout: Discovery phase timeout override in seconds. Current default from argument_defaults.json: null (auto budget).

How to connect to different networks on the Pi

nmcli dev wifi
nmtui

Common examples

Manual streamer setup:

python3 camera_streamer.py --base-port 5555 --camera-ids 0 2 4 --jpg-quality 30 --target-fps 30

Discovery receiver with filter:

python3 camera_receiver.py --auto-config on --streamer-name-filter cam-pi-1 --show-stats on

Simulated cameras:

python3 camera_streamer.py --simulate-cameras 4

Troubleshooting

• No camera detected: verify device nodes and permissions, then run v4l2-ctl --list-devices.
• Receiver cannot connect: verify stream host/ports and firewall rules.
• Discovery not finding streamer: verify same subnet and matching discovery port.

Notes

• Stream stats overlay is available with --show-stats on.
• If a camera is physically disconnected, a streamer restart may still be required depending on device/driver behavior.