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Video frames playing out of order post and replies

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Frames display out of order, so motion oscillates when it is actually linear
Alan Goldblatt
1 Posts

Using a video made on an iPhone in MOV format, and using Tracker 6 on a Windows 10 machine, the video displays frames out of order.  A cart moving along a track goes forward for 3 frames, backward for 2 frames, forward for another 3 frames, backward for 2 frames, and so on.  Interestingly, when we try to play it in a different video application on Windows, the necessary codec is missing.  But apparently xuggle contains the correct codec, as it displays in Tracker.


Has anyone else seen this behavior?


Replies to Frames display out of order, so motion oscillates when it is actually linear

Re: Frames display out of order, so motion oscillates when it is actually linear -
Seth Fraden
2 Posts

I've seen the same thing with movies recorded on iPhone with the latest version of Tracker. Students in class are very frustrated. Doesn't seem to happen on older .mp4 movies, but is associated with recent .MOV iphone movies. Also, doesn't seem to happen on Android.



Re: Frames display out of order, so motion oscillates when it is actually linear -
Darren Bly
1 Posts

Have had the same problem with working with Tracker on Macs. Loading the video files at 480p seems to be a fix.



Re: Frames display out of order, so motion oscillates when it is actually linear -
Jordan McIntosh
1 Posts

Converting the video to mp4 seems to fix the issue.



Re: Frames display out of order, so motion oscillates when it is actually linear -
Carson Perrons
1 Posts

I know I am a bit late to this, but I find it happens to even .mp4 files but only when I skip to any frame forward or backwards whilst the recording is playing. To fix it: It seems to stop jittering when I wind back the video to the very beggining (paused) and then hit play. Then I pause it before setting a frame or using the slider at the bottom of the screen. This may not work for everyone, but the issue has been plagueing me for a while and I don't have any easier solutions for my end yet.



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