wrMTrck does not follow my objects when moving faster

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wrMTrck does not follow my objects when moving faster

Hi all,

I am trying to analyze videos of swimming performance in tadpoles using
wrMTrck in ImageJ. Camera was placed vertically ~90cm above the swimming
tracks. I could perform analyses using wrMTrck. However, after some videos,
I realized parts of some movements of the tadpoles were not 'recorded' in
the analysis of wrMTrck. Tadpoles have different size and by changing the
'minSize' criterion, the program was able to detect all sizes. However, it
seems that when tadpoles swim really fast, the program is not able 'to
follow' them nor to record their speed. I tried to change the maxVelocity
but it does not change anything.

Before using wrMTrck, I set a scale and adjust the threshold of the image so
that tadpoles are well visible in dark while the rest of the image is white.
The program is able to follow tadpoles when they swim slowly without any
problem but when they swim *really fast*, the tracking does not work anymore
(when fast, that is still OK). I think maybe it is because when they swim
really fast, there is like a distorsion of their body.. I changed also the
maxAreaChange but that does not nothing either.

I thought maybe you could give me some advices of what to do so that the
tracking can work also for the fast movements.
Indeed, I am searching for the maximum speed at which each tadpole can swim
at different temperatures. Consequently, it is very important I can get
these values.

Do you have any ideas?

Thank you.

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