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