I'd say that Blue Iris is, uh, 'medium'. More recent versions include an object-tracking motion detection engine that's a lot better at rejecting scene changes

I'd say that Blue Iris is, uh, 'medium'. More recent versions include an object-tracking motion detection engine that's a lot better at rejecting scene changes (e.g. camera switching between day/night mode) by simply discarding the motion if the 'object' makes up a very large portion of the image area. I've set it to be very sensitive and I only occasionally get false positives - I could probably eliminate those if I tweaked it a little more. I've seen at least one company that actually sells a BlueIris plugin that implements some kind of ML human detection as a way to filter alerts, but I haven't given it a try. Xeoma has some "AI" features like this if you pay for the higher-tier license, but tbh I've found Xeoma's base motion detection engine to be so unreliable that I just wouldn't recommend it for this application - but to be fair it was also a while back that I was using it and they may have improved things since then.