Building a Webcam CCTV Recorder Using Flask
In this blog post, I walk you through the design and development of a lightweight CCTV system using a regular webcam and a Flask-based Python web app. This application serves live video through a web browser, records hourly footage automatically, and lets you view and download those recordings with ease.
💡 Key Features
- Live MJPEG stream from your webcam
- Automatic hourly recording with timestamped filenames
- Start and stop recording from the browser
- Explore saved recordings within the web interface
- Runs efficiently on Docker and compatible with Windows
⚙️ System Architecture
The app leverages Python’s threading to keep recording and streaming parallel. OpenCV handles camera input and frame encoding, while Flask powers the server and routes. I used a shared buffer protected by a lock to avoid conflicts between the stream and recorder.
📁 Recording Directory
All videos are saved in static/recordings. Each file is encoded using MP4V at 30 FPS and stored as a separate hour-long segment.
🧪 Challenges
- Proper threading to avoid deadlocks and broken feeds
- Ensuring clean start/stop toggling of the recording logic
- Docker compatibility and OpenCV camera device mapping
🚀 Dockerized Deployment
The app runs in a Docker container with access to /dev/video0. This makes it portable and easy to deploy on edge devices or remote systems.
📷 My Setup
Host: TUF GAMING FX504GE OS: Windows 10 + WSL 2 (Docker) Camera: Built-in HD Webcam Python: 3.11 Libraries: Flask, OpenCV
You can find the full project on GitHub.
Updated : 10th June 2025