The dedicated homebridge-rpi-camera plugin makes the ffmpeg process crash for me.

According to this comment, this adapted config work smoothly.

{
	"platform": "Camera-ffmpeg",
	"cameras": [{
		"name": "Pi Cam",
		"videoConfig": {
			"source": "-re -r 6 -s 1280x720 -f video4linux2 -i /dev/video0",
			"stillImageSource": "-s 1280x720 -f video4linux2 -i /dev/video0",
			"maxStreams": 2,
			"maxWidth": 1280,
			"maxHeight": 720,
			"maxFPS": 6,
			"vcodec": "h264_omx"
		}
	}]
}