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iPhone video jitters

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Slow motion video
lydia sobh
1 Posts

I filmed a 5 second video on my phone and imported it onto tracker. Everytime I upload it its playing in slow motion. I tried un marking the "play all steps" and it did not work. I need to turn this assignment asap. I'm working on a mac, I have version 6.1.2 and I used an iphone 12 to film my video.


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Re: Slow motion video   (Douglas Brown - )
Re: iPhone videos seem to play out of sequence
Wolfgang
192 Posts

Have you tried to covert the video clip into a different video format?  Video formats and codecs are constantly evolving and a video clip converter is an essential tool when doing video analysis.  The OSP-Tracker team has had good luck using online cloudconvert software.

https://cloudconvert.com/mp4-converter

The mp4 with H264 codec should work with both Java and JavaScript versions of Tracker.


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Re: iPhone videos seem to...   (Paul Camp - )
Re: iPhone videos seem to...   (Wolfgang - )
iPhone videos seem to play out of sequence
Paul Camp
3 Posts

At least that's my best guess. I have not seen this prior to this semester but I've seen it a dozen times in the last week, always with iPhones.

The frames appear to be playing out of sequence. E.g. frame 1 then frame 3 then frame 2. But Tracker does not pause on frame 3. So doing a single frame advance in Tracker causes the tracked object to jump ahead and then fall back to an intermediate position.

I'm not quite sure how to interpret this because I'm not quite sure what is actually happening. But it only happens with iPhone video so it has to be something screwy with Apple. Usually, so far, retaking the video fixes it. But I'd rather not deal with it at all.


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Re: iPhone videos seem to...   (Ted Diehl - )
Re: iPhone videos seem to...   (Sebastian B - )
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