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Using units in Tracker post and replies

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Does Tracker Use (or require) Units?
Todd Longfellow
1 Posts

Greetings, and thanks so such for a wonderful tool!

I am guessing that, outside of degrees or radians, Tracker is pretty much unitless. Is this correct?

Thank you for considering my question.

~todd

Post edited May 28, 2013 at 4:13 AM EST.


Replies to Does Tracker Use (or require) Units?

Re: Does Tracker Use (or require) Units? -
Douglas Brown Avatar
Douglas Brown
416 Posts

That's almost right. Tracker is unitless except for degrees/radians and also time is assumed to be in seconds. But mass and distance units are up to the user...  Doug



Re: Does Tracker Use (or require) Units? -
LYDIA KOUTROUDITSOU
1 Posts

Hello Doug,

Is it possible to measure pixels in TRACKER?



Re: Does Tracker Use (or require) Units? -
Fernando Ferro
9 Posts

Measure Pixels in which units?
By definition, a pixel measures 1x1 unit.
Could it be that you want to count the number of pixels?



Re: Does Tracker Use (or require) Units? -
Douglas Brown Avatar
Douglas Brown
416 Posts

If a Tracker tab is never calibrated then by default the units are really image pixels.

However, you can use any length and mass units you want. Defaults are m and kg. You can change units by choosing the menu item Coordinate System|Units. You can also choose to show angles in radians or degrees.



Re: Does Tracker Use (or require) Units? -
Görkem Cenk Ye?ilova
1 Posts

Hello Douglas, I wonder one thing in terms of point mass. So, when we chosee the point mass, a mass unit section appears on the interface. It shows default mass value 1.000kg. So, is this section for the mass of the moving object in the video? For example, we will track a car and we need to enter the weight of the car into this section, right?



Re: Does Tracker Use (or require) Units? -
Douglas Brown Avatar
Douglas Brown
416 Posts

Yes, you should enter the actual mass of the object being tracked.


> So, when we chosee the point mass, a mass unit
> section appears on the interface. It shows default
> mass value 1.000kg. So, is this section for the mass
> of the moving object in the video? For example, we
> will track a car and we need to enter the weight of
> the car into this section, right?



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