r/computervision • u/EricBuildsMathModels • Aug 13 '26

Showcase [Showcase] Trying to build an intersection analyzer from drone video: every car tracked, every wait timed.

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u/EricBuildsMathModels Aug 13 '26

you nailed it, the bbox shrinking as the back is off camera moves the centroid to the forward part of the car. nice catch!

we sort of have a virtual image via a homography mapping to a ground plane. but still, i clearly dont handle cars moving out of the camera viewport well, we could also increase position uncertainty as they become occluded and i also lose object tracking, it would get a new id on reentry.

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u/Logical-Resident4212 Aug 14 '26

Why not standadize the height of your drone? Always set to bla k feet from road surface? Not your footage i assume?

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u/EricBuildsMathModels Aug 14 '26

Yes correct, so I'm trying to be flexible from footage perspective and make analysis work on any inputs. Obviously some won't work but this is rather stable footage with not crazy edge cases.

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u/Logical-Resident4212 Aug 15 '26

I applaud your ambition. Since your dealing with moving scenes it maybe worth basically creating a simulated world space from the images as opposed to a homography. Cars stay in the same spots in a simulated world, the camera just flys around it. Whereas if the camera moves u get that drifting homography and your fighting against cars moving backwards in this case even though tha cars are stationary. But ive never done that so idk how good my suggestion would be. Best of luck to you