P3 IR Camera

Python driver and viewer for P3-series USB thermal cameras.

Devices:

• P1: VID=0x3474, PID=0x45C2, 160×120 native resolution
• P3: VID=0x3474, PID=0x45A2, 256×192 native resolution

Disclaimer: This is an independent open-source project. It is not affiliated with, endorsed by, or connected to any camera manufacturer. Protocol details were determined through USB traffic analysis and experimentation.

Features

• USB driver for frame capture and device control
• Real-time thermal viewer with multiple colormaps
• Temperature measurement at cursor position
• Temporal noise reduction and digital detail enhancement
• Multiple AGC modes (factory hardware AGC, temporal percentile, fixed range)
• Shutter/NUC calibration control
• High/Low gain mode switching

Installation

git clone https://github.com/jvdillon/p3-ir-camera
cd p3-ir-camera
pip install -e .

USB Permissions (Linux)

Create a udev rule to allow non-root access:

sudo tee /etc/udev/rules.d/99-p3-ir.rules << EOF
# P1 camera
SUBSYSTEM=="usb", ATTR{idVendor}=="3474", ATTR{idProduct}=="45c2", MODE="0666"
# P3 camera
SUBSYSTEM=="usb", ATTR{idVendor}=="3474", ATTR{idProduct}=="45a2", MODE="0666"
EOF
sudo udevadm control --reload-rules
sudo udevadm trigger

USB Driver (Windows)

pyusb requires a libusb-compatible driver. Use Zadig:

1. Download and run Zadig
2. Options → List All Devices
3. Select the camera (VID 3474, PID 45C2 for P1 or 45A2 for P3)
4. Select WinUSB driver
5. Click "Replace Driver"

Usage

Viewer

# Use P3 camera (default, 256×192)
p3-viewer

# Use P1 camera (160×120)
p3-viewer --model=p1

# Use P3 camera explicitly
p3-viewer --model=p3

Controls:

• q - Quit
• h - Toggle help overlay
• c - Cycle colormap
• a - Cycle AGC mode
• d - Toggle DDE (detail enhancement)
• p - Toggle enhanced mode (CLAHE + DDE)
• x - Cycle scale/interpolation mode
• t - Toggle reticule
• s - Trigger shutter/NUC
• g - Toggle gain mode (high/low)
• r - Rotate display 90°
• m - Mirror display
• +/- - Zoom in/out
• e - Cycle emissivity presets
• 1-9 - Set emissivity (0.1-0.9)
• D - Dump raw thermal data to file
• Space - Screenshot

Library

from p3_camera import Model, P3Camera, get_model_config, raw_to_celsius

# Use P3 camera (default)
camera = P3Camera()
# Or use P1 camera
# camera = P3Camera(config=get_model_config(Model.P1))

camera.connect()
camera.init()
camera.start_streaming()

ir_brightness, thermal_raw = camera.read_frame_both()
temps_celsius = raw_to_celsius(thermal_raw)

# Center coordinates depend on model
# P1: (59, 80), P3: (95, 128)
print(f"Center temp: {temps_celsius[temps_celsius.shape[0]//2, temps_celsius.shape[1]//2]:.1f}C")

camera.stop_streaming()
camera.disconnect()

Protocol Documentation

See P3_PROTOCOL.md for USB protocol details.

Contributing

This project provides initial scaffolding for a P3 thermal camera application. There's significant potential to build something great here, and contributions are welcome!

Some areas that could use help:

• macOS support - USB handling on macOS
• GUI application - Qt/GTK interface beyond the OpenCV viewer
• Recording/playback - Video capture with thermal data preservation
• Radiometric analysis - Region statistics, spot meters, isotherms
• Calibration tools - Blackbody calibration, emissivity tables
• Documentation - Protocol details, hardware information

If you have a P3 camera and want to help improve this tool, PRs are welcome!

License

Apache 2.0