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Tracker 4.75 on MacOS X - autotracker slows way down for long files post and replies

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Tracker slows down in autotracking as the number of frames searched increases - possibly a bug? - Jan 29, 2013 at 10:56AM
Eric Bowman
1 Posts

First, I would like to thank those who have worked on tracker! It's an excellent program, and in these days of constrained budgets at universities Tracker has the potential to replace software that costs our labs thousands.

I am new to Tracker and I have been trying to use tracker to record the positions of little beasties (rats) as they explore their environment and interact with each other.  I simply place an innocuous circular decal on the animal's fur and record their position with a web cam.  The autotracking feature in Tracker works amazingly well (in some cases as good as Noldus's Ethovision), but I have experienced issues with large files.  As you might imagine, rats sometimes rear, groom themselves, chase their tail, dart about suddenly, or rollover, thereby either partially obscuring the colored decal or blurring it.  Thus, occasionally I have to insert a new key frame to get the autrotracking work again.

The problem is that as the number of frames searched increases (say, above 1400 or so), Tracker begins to slow way down both in terms of displaying the frames being searched and in terms of the user interface (it can take 10's of seconds to get the 'new key frame' cursor for instance).  Possible this is a natural consequence of adding new points to the track, but I wondered if might be a bug.  This occurs whether I use QT with 32-bit JAVA or Xuggle with 64-bit Java.  Also, it is not affected by the memory I assign to Tracker.

System information:
iMac, 27", Mid 2011
CPU: 3.4GHz i7
Memory: 16 GB
GPU: AMD Radeon HD 6970M 2048 MB
Mac OS X 10.8.2

Any help or advise would be appreciated.


Replies to Tracker slows down in autotracking as the number of frames searched increases - possibly a bug?

Re: Tracker slows down in autotracking as the number of frames searched increases - possibly a bug? - Jan 29 2013 5:41PM
Douglas Brown Avatar
Douglas Brown
110 Posts

Hello Eric,

I have never tested the autotracker with such a long video so it is certainly possible that it is doing some data updating (including multiple derivatives) that takes a long time with so many points. It might be possible to me to fix this by making a way to turn off automatic data updating and instead updating only when you click the Refresh button at the right end of Tracker's toolbar. Of course, it could be something else entirely...

Do you have a long, autotrackable video that exhibits this behavior (perhaps not bigger than 100MB) that I could use for testing? Perhaps you could post it on a web server (DropBox?) and send the URL to my personal email (link on the Tracker web site) so I can download it.

I'm certainly pleased to hear that the autotracker is working well for you aside from the speed issue :-)

Doug



Re: Tracker slows down in autotracking as the number of frames searched increases - possibly a bug? - Feb 26 2013 1:14PM
Douglas Brown Avatar
Douglas Brown
110 Posts

Eric,

In Tracker version 4.80 you can autotrack long videos MUCH faster by temporarily turning off autorefresh. This prevents the plots and tables from redrawing themselves after every step.

To turn off autorefresh, click the refresh button at the right end of the toolbar and uncheck the box.

Happy tracking! Doug



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