Why two streams
Detecting on a 4K main stream eats the CPU, so Frigate analyses the small sub stream (640×360 at 5 fps) and records the main one. go2rtc connects to the camera once and serves everyone (Frigate, Home Assistant, the browser), so the camera does not hit its connection limit.
Which detector
CPU is fine for one or two cameras. On an Intel N100 or newer mini PC use OpenVINO: the integrated GPU handles several cameras. Google Coral (USB or M.2) is the classic choice for a Raspberry Pi or an older PC. Frigate in Docker needs /dev/dri (Intel) or the Coral passed in: docker-compose with Frigate.
Stream URLs for your cameras: RTSP generator. Check the YAML: YAML checker.
What to buy
Google Coral USB: AliExpress · N100 mini PC: AliExpress
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