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Track Calibration Point Pair post and replies

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How to track the Calibration Points - Jun 4, 2013 at 7:47AM
Martin Peters
13 Posts

First of all: Thanks for this great tracking tool! It's very easy and fast to use.

But I got a problem with tracking the Calibrations Points. So I created the points as the help-pdf says and marked them with the shift-click. Now I want these points to stay at the points of interest although they move in the video. So I thought let these points become trackpoints. But they keep their position and when I open the Track-menu and choose Calibration Point A it says: "Please click the video feature you wish to autotrack. Mouse over the controls above to learn more..."
But I already chose the points of interest. So I don't know why the search-button is grayed out.

Hints and help welcome.



Edit: My aim is a coordinate system which tracks a moving object

And how can I define a second key frame? I want to track two points of a moving object and I am searching for a solution without a second masspoint (because the tracking of 1800 frames takes almost 15 minutes -> this is one single minute of the video I want to analyse)

Post edited June 4, 2013 at 7:54 AM EST.

Post edited June 4, 2013 at 8:53 AM EST.

Replies to How to track the Calibration Points

Re: How to track the Calibration Points - Jun 04 2013 12:39PM
Douglas Brown Avatar
Douglas Brown
161 Posts

Martin--are you using the latest version (4.80) of Tracker? If not, I recommend you update.

After you have marked the calibration points, you should open the autotracker by clicking the autotracker button on the toolbar (to the right of the "Create" button). In the autotracker, set the Target Track to the calibration points track and Target Point to either point 1 or point 2.  Then you need to shift-control-click the video to create a key frame for the autotracker (even though the point has already been marked--key frames and marked points are not the same thing!).

Now you should be able to use the Search button(s).

Does this solve the problem? Doug

Re: Re: How to track the Calibration Points - Jun 05 2013 4:33AM
Martin Peters
13 Posts

Thanks for this fast answer, Doug!

If I do it like you said it's working! Great!
And yes I'm using the latest version.

Maybe you can help me with another problem as well? I want to measure a revolution speed and therefore tracked a rotating point. When the autotracker gets to a frame in which the tracked point is not visible it stops and asks if I want to skip the frame.
Because one successful track per turn is enough for my revolution speed measurement I don't care about this question which interrupts the search.
Is there any possibility to skip these frames automatically instead of clicking each time "skip" manually? This would speed up my work with "Tracker".

Best regards

Re: How to track the Calibration Points - Jun 05 2013 11:13AM
Douglas Brown Avatar
Douglas Brown
161 Posts

Martin, there's no way to have the autotracker automatically skip frames in which it fails to find a match. But if you only need one point per revolution you might be able to set the video clip start frame and step size in such a way that the only frames included in the clip are those in which the tracked point is visible.


Re: Re: How to track the Calibration Points - Jun 06 2013 10:35AM
Martin Peters
13 Posts

Great idea!
I'll check this out soon.

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