Raspberry Pi Average Speed Camera System

I have a Raspberry Pi 4 and a USB-powered camera waiting to be turned into a fully automated average-speed enforcement system focused on cars. The goal is simple: capture each vehicle as it passes Point A and Point B, compute the travel time between those marks, derive the average speed, and immediately flash an on-screen alert whenever the preset limit is exceeded.

Here is what I need delivered:
• Software that runs natively on Raspberry Pi OS, leverages OpenCV (or an equivalent library) for vehicle detection and tracking, and stores all processing locally on the Pi.
• Accurate timestamp matching from the two checkpoints so every car’s travel time is reliable, even during heavy traffic.
• Real-time calculations that compare the measured average speed against a configurable limit and push instant visual feedback to the HDMI display connected to the Pi.
• Automatic capture and storage of violation snapshots or short video clips, along with a log file that lists plate or vehicle ID (if detectable), timestamps, measured speed, and limit exceeded.
• A concise setup guide covering hardware wiring, software installation, configuration of distance and speed thresholds, and basic troubleshooting steps.

Acceptance criteria
– System identifies >95 % of passing cars in daylight conditions.
– Speed calculation error margin ≤ 3 %.
– On-screen alert appears within one second of violation detection.
– All logged data persists after reboot and can be exported via USB or SCP.

When you place your bid, please highlight your direct experience with Raspberry Pi computer-vision projects or similar speed-detection solutions, and briefly note the libraries or frameworks you prefer to use. Source code, install scripts, and documentation are all part of the final hand-off.