Strange alert images; alert shows event not in video

[jefft]

Hi All,

I've seen two strange things happen with my BI system recently and I'm stumped; hopefully someone can help me to work out what's causing these!

(1) The 'Alerts' folder is full of JPG files all of ZERO BYTES! I don't have high-res JPEG specified in the 'Triggers' tab for any of the cameras; they're all database only alerts. What are these files, and why?

(2) Last night, a camera recorded an alert for an event - quite noticeable as it was a fox taking a dump right in front of camera! - and the video shown when I initially hover over that entry in the alerts list shows the fox. However, when I play back the clip, there's no such event recorded... there was video loss from that camera for ~30s about a minute before the alert, but the timecode shows constant video through the alleged alert time. I've tried playing back the full clip for that period a few minutes either side of the alert time and there's no sign of the vulpine misdemeanour. This was all around 23:00, so there's no interference from the change to summer time (and anyway my whole system stays in UTC all year).

Anyone have any ideas? Thanks!

[TimG]

I'm not sure about the first issue. Could the second issue be the difference between a sub stream and main stream ? The video loss you experienced could affect the streams differently.

[jefft]

That's a thought; i thought the camera was dropping out completely (it's a wi-fi thing, so prone to do that), but perhaps it's just getting low bandwidth for a moment and can't get the main stream through. You're right, that probably would cause the thumbnails (sub-stream, I guess) to be there and the main video not.

Either way, I think I have to move that camera somewhere the wi-fi is better; it seems to be within range of three access points, but none of them quite close enough for consistently good performance.