Hi there,
some years ago, I had bought a USB video grabber like this one:
Easyday Easycap DC60 USB 2.0 Audio Video Grabber Converter for Windows 7/8/10 Amazon.de
I had used this to stream the signal of my analogue video door camera to a Raspberry Pi which worked quite well.
Now I thought it would be handy if I could stream the signal of the USB video grabber to Home Assistant.
How can I integrate such a USB video grabber to Home Assistant?
Hi mate, I am having the same project planned and wanted to ask how did you went with your project?
Hey there! I have not pushed this project further yet - there were numerous other projects waiting for my attention. But I would still be very interested in this! If you get it working, would be great if you’d let me know.
So basicly you teach me and i teach you 
As i did not start the project so far, but what i found out is, the part missing for you.
You generate a rtsp stream on your raspberry and than feed that into homeassistant via Generic Camera - Home Assistant (home-assistant.io) or you use a system like frigate and use than the integration in HA.
Great! So which part is missing for you?