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Sports biomechanics: More than 2 calibration points?

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Sports biomechanics: More than 2 calibration points?
Mikkel Roald
5 Posts

First of all, I'm a big fan of Tracker and use it for kinematic analysis in track and field events, and really appreciate all the time and effort put into it!

For horizontal jumping events (long jump, triple jump), I record stationary videos straight from the side with multiple landmarks on the ground (every couple of meters). However, as it is often preferred to cover up to 20m and it is not feasible to stand 50m from the track I wondered if it possible to correct for this? I have attached a representative photo - in this photo the velocity of the jumper will be underestimated in the right side of the photo.

I am thinking of trying the Radial Distortion filter, but since I don't really want to correct for lens distortions I have my doubts with this.

Another suggestion, which I haven't been able to locate in Tracker, could be the use of 3 or more Calibration Points to extrapolate changing reference frame towards the extremities. Would this be something to consider for the future? For the example above there are multiple small 1m marks which could easily be used. I have attached a doodle of the idea, hope it makes sense.

Please let me know what you think,
Best regards

Attached File: triple-jump-1200.jpg

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Re: Sports biomechanics: ...   (Mikkel Roald - )
Re: Sports biomechanics: ...   (Jim Simpson - )
Re: Sports biomechanics: ...   (Mikkel Roald - )
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