# Repeated frames in videos

**URL:** <https://community.drivendata.org/t/repeated-frames-in-videos/1467>\
**Category:** N+1 Fish, N+2 Fish\
**Created:** [September 30, 2017, 4:02am UTC](https://community.drivendata.org/t/repeated-frames-in-videos/1467 "2017-09-30T04:02:14Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![fishysisi](https://avatars.discourse-cdn.com/v4/letter/f/f04885/32.png) [@fishysisi](https://community.drivendata.org/u/fishysisi)\
**Post date:** [September 30, 2017, 4:02am UTC](https://community.drivendata.org/t/repeated-frames-in-videos/1467/1 "2017-09-30T04:02:15Z")

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Hi, I was browsing the videos and it seems there are quite a few repeated frames.  
e.g. taking a random video from the training set, 00WK7DR6FyPZ5u3A.mp4 appears to repeat every 6th frame.  
I checked this on the [CVision annotation tool](https://github.com/BGWoodward/FishAnnotator/releases) linked from the instructions.  
Any idea what the underlying issue behind that is? I’d like to understand whether the repeated frame corresponds to 1,2,3,3,5,6, where frame 4 is skipped entirely but time is preserved, or to 1,2,3,3,4,5…, where the true timing of the sequence is broken but frame 4 is shown. I suspect the former?  
Thanks!

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**Author:** ![BGWoodward](https://avatars.discourse-cdn.com/v4/letter/b/eb9ed0/32.png) [@BGWoodward](https://community.drivendata.org/u/BGWoodward)\
**Post date:** [October 1, 2017, 12:47am UTC](https://community.drivendata.org/t/repeated-frames-in-videos/1467/2 "2017-10-01T00:47:35Z")

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Hi fishysisi,

It is 1,2,3,3,5,6. This is an artifact of the encoding process and how skipped frames were handled when re-encoding so they were clean enough to play in most video players. Due to time constraints it was not possible to re-encode the videos with duplicate frames removed and timing preserved. Please let me know if you have any further questions on this subject.

Thanks,

-Ben