smartcam

Smart, low-cost, self-contained, cooperative IP security camera system in .NET for Raspberry Pi devices.

2020-06 - This is a new project in the earliest stages of planning, testing, and design. As I make progress I will begin documenting things like the basic setup process.

Requirements / Assumptions

• Raspberry Pi 4 with 4GB RAM (likely also compatible with v3, I haven't tried yet)
• Camera using the Pi's on-board camera port (5MP preferred over newer 8MP version)
• .NET and ASP.NET runtimes; SDK not required on-board the Pi; currently targeting 3.1.x
• Raspbian OS (lite is OK but some of the setup process may be easier through the GUI)
• Network-based centralized storage for video clips (e.g. a NAS or dedicated file server)
• Cameras are on a trusted network (e.g. adequately firewalled on your home network)

Features / Goals

• Fast new-device setup: copy SD card, change one config file, boot, rename the Pi, run updates
• Self-organizing: the cameras discover other smartcams on the same network (group triggers)
• Low traffic: 100% local processing, only copying recordings to storage is high-traffic
• SD-card friendly: caching and encoding on ramdisk, logging on network
• Self-managing: systemctl watchdog processes
• User-friendly: easy web-based UI for interacting with the entire system
• DHCP-friendly, no need to pre-assign IPs (a common requirement with IP cams on DVR servers)
• TBD: support MJPEG / RTSP for interactive browser viewing?

The smartcam Process

• Console program on each Pi device
• Manages the pre-record buffer
• Performs motion detection
• Manages recording and saving to storage
• Communicates via websockets with local "smartcam-host" process

The smartcam-host Process

• Web server on each Pi device
• Basic browser UI for interacting with an individual camera (not secure)
• Simple REST API for interacting with other smartcam-host processes
• ASP.NET Kestrel reverse-proxy setup behind ngnix
• Interacts with "smartcam" process via websockets
• Discovers other smartcam servers on the same network
• Sends and receives group notifications when motion detection triggers recording
• Manages network storage maintenance (trimming old files by date and/or free space)

The smartcam-master Server

• Web server, one per network, not necessarily Pi-hosted
• UI provides a system-wide view (similar to traditional IP cam DVRs)
• Basic security (we assume this is potentially publicly accessible)
• Interacts with all known smartcam-host processes

Notes About Network Storage

• A top-level directory is dedicated to all cameras, for example //NAS1/smartcams
• Each smartcam creates it's own subdirectory, for example //NAS1/smartcams/frontporch
• The smartcam updates discovery.txt with information to help the hosts with discovery