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Tracking Distance from the Camera post and replies

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Is Tracker able to track individual distance from the camera?
Tyler Lue
1 Posts

Hi,

I was wondering if Tracker was able to track an individual's distance from the camera. All of the videos I am seeing online are in 2D space and my project is aiming to analyze individuals in 3D space. More specifically, we are trying to estimate the distance of an individual from the camera. We have calibration videos where we have a 20m rope that extends from the camera going away from the camera. I have attached a photo of the calibration video I am trying to use. In the other videos, it will be the same location but instead with animals in the frame whose distances we are aiming to measure. The red flags on the rope indicate 5m distances from the camera. Using a calibration stick on the rope does not yield accurate measurements as it says the first flag is 15m away (y=~15), which I presume is because Tracker is only measuring in 2 dimensions.

Please let me know if measuring distance from the camera is something Tracker can achieve and if so, how I would go about this.

Thanks,
Tyler

Attached File: Calibration_54.png


Replies to Is Tracker able to track individual distance from the camera?

Re: Is Tracker able to track individual distance from the camera? -
Fernando Ferro
14 Posts

As far as I know Tracker measure pixels in the image plane, (2D) and translate them to the units you set.
It is not possible to know what happens in the direction of the optical axis of the camera when the focal length is unknown.



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