Does BlueIris need a constant stream of ONVIF Motion events in order to keep motion triggered? Or is it possible to configure a camera in BlueIris so a single pair of IsMotion:True and IsMotion:False events are sufficient to keep motion triggered between them?
Today I updated a Hikvision DS-2CD2442FWD-IW camera to firmware version v5.5.0 ("recently" released 2017-07-25) from 5.4.4. This release defaulted ONVIF off so initially my camer's motion events appeared broken until I went in on the device to ONVIF on and created an ONVIF user account using the same username/password as my login for the camera. BlueIris is now picking up the ONVIF events again. (a screenshot of this camera's Trigger settings: https://i.imgur.com/yXvGZtP.png)
However, motion events aren't "sticking" on like they used during actual motion in the scene. They still do for another similar camera, a Hikvision DS-2CD2432F-IW (firmware v5.4.5) so that seems to indicate it's a problem camera-side. After comparing the ONVIF events for the two cameras I think I've found out why.
The working camera shows a stream of IsMotion:True events until the source of the motion (say a baby) is removed at which point a couple of turnisMotion:false are sent and then stop altogether: https://i.imgur.com/Zo1OUlX.png
The other camera now only shows a single IsMotion:True event during the duration of motion and only sends IsMotion:false when motion stops: https://i.imgur.com/hQ0PKA7.png
(I'm unable to downgrade its firmware to confirm if the prior version sent a stream of IsMotion:True events)
In both screenshots, ONVIF Device Manager is connected to the camera in question and showing the Events view. For the second camera the selected last Motion event shows IsMotion:true is set. I had been in out of of that room prior but during that last event I had turned on a baby swing in view so motion was occuring 9:18pm and onwards, i.e. IsMotion is implied "true" for the entire time. Then at 9:27pm I went in and turned off the baby swing and we then see IsMotion:false: https://i.imgur.com/ot7ZevD.png
However, BlueIris was only triggered on just that first IsMotion:true signal so it stopped "detecting" motion immediately after that and stopped recording 10 seconds later due to the camera's configured break time.
In general I try to keep all motion detection on my devices and signal BlueIris via signals so as to keep CPU utilization as low as possible on my BlueIris NVR system. I've tried a variety of ways to get the Hikvision 2442 to send more motion events but just haven't been successful. Ideally BlueIris would remain triggered in the Motion-detected state after receiving the IsMotion:True event until it receives IsMotion:False. But I'm assuming that'd be a hard problem because BI would then need to handle any "missing message" scenarios.
As it is I can either workaround this by turning on BlueIris' motion detection but I'd rather not as I'm already nearing full load on my NVR's CPU.