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Tracking time intervals instead of motion? - July 19 at 10:10:PM
Milos Krsmanovic
2 Posts

I was recently introduced to Tracker and so far I really like it. I find it easy to use and the autotracking feature saved me a lot of time on a couple of occasions.

I have a question, or if you will a suggestion, regarding tracking of time intervals for periodic motion. Say I have a rotating shaft that I'm filming in a way so there is a unique feature that comes into the frame at regular intervals. Perhaps a marking I made or unique glare or whatever. Would it be possible to track the time between the two revolutions? To the best of my knowledge, this is not possible to do in Tracker. But I'm wondering if it is possible to implement or if there is some sort of clever hack I can do to make this work. What gave me the idea is seeing how well Tracker followed some funny, low contrast shapes in my previous attempts. It was really impressive.


Replies to Tracking time intervals instead of motion?

Re: Tracking time intervals instead of motion? - July 20 11:39:AM
Douglas Brown Avatar
Douglas Brown
276 Posts

That's a great idea. Have you used the Search Fixed Area feature of the autotracker?

When you hold down the shift key the autotracker Search button changes to Options. Click it and choose Search Fixed Area to have the autotracker search in every frame without stopping. You end up with positions wherever a match is found and gaps where none. The template is fixed so it's always matching the key frame. You can see the gaps as red lines in the data table if you turn them on (if you son't see a Gaps button, check the preferences). Maybe there's a way to get your period data from this?

It would be neat to set positions of an RGB region this way, but I'm not sure it works at this point.  It will in the future! Doug

Say I have a rotating shaft that I'm filming > in a way so there is a unique feature that comes into > the frame at regular intervals. Perhaps a marking > I made or unique glare or whatever. Would it be possible > to track the time between the two revolutions? To > the best of my knowledge, this is not possible to > do in Tracker. But I'm wondering if it is possible > to implement or if there is some sort of clever hack > I can do to make this work. What gave me the idea > is seeing how well Tracker followed some funny, low > contrast shapes in my previous attempts. It was really > impressive.



Re: Tracking time intervals instead of motion? - July 24 8:26:PM
Milos Krsmanovic
2 Posts

Thank you for the reply and the suggestion. I played with it briefly with some success. I'll investigate it further.

I appreciate that you took this suggestion into consideration.



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