Many cameras do events of a set length, this could for instance be + 10 seconds ( from a memory buffer so you have footage from before event ) to 20 - 30 seconds after a event.
in that case you cant really use length of file for a search parameter, as all events would be 30 - 40 seconds long.
Yet other cameras do segments, this could be for instance 3 minute like i use, my SG camera actually save 2 of those from each camera in case of a event.
The only events i can see being different in length / file size would be the ones created by motion detect, but motion detect are not super good, at least not if you park in a place with "a lot" of activity, cuz then the camera might well be recording +90% of the time.
If you live down a dead end road, then it would be better as you dont have much traffic / movement going on there, still many cameras with motion detect, just a leaf fluttering by will set off the camera or a bird, in general the mode seem to be too sensitive on most cameras.
Then there is the radar cameras detection movement that way, these might not be so sensitive, still if you park curbside on a main road, chance are it will probably also generate a lot of events.
It is true dashcams have often messed with peoples radios, but DAB and satellite radio is what i have heard off mostly, but i also recall a situation where a camera meddles with the cars build in NAV system.
AM radio is new to me,,,,, dident even expect people listened to AM radio these days.
WIFI woes / smart camera woes, those are also real, pretty much any camera, and a update of IOS / new apple phone and you are lost, and it is not like Android based devises are much better, here you might have to do hoop jumps like airplane mode and what not to get a connection.
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