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Video freezes on step back

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Video freezes on step back - Aug 1 at 12:46AM
Steve Draper
2 Posts

Hi Doug/everyone.

Awesome software!

I'm using Tracker 5.0.1 (and have been using it since early 4.x) on Windows 10 with my Physics classes.

We have Casio Exilim High Speed cameras that record in .mov format. Mediainfo software says they are MPEG-4 Quicktime AVC format.

I can load them into Tracker fine. They play and step forward ok. But if I try to step back (one frame), the video freezes. The message log says this (multiple times):

'CONSOLE: 14:41:02.893 [AWT-EventQueue-0] ERROR org.ffmpeg - [h264 @ 0x179fa330] number of reference frames exceeds max (probably corrupt input), discarding one'

I noticed in Mediainfo that the frame rate of the MOV file says '29.970 (30000/1001) FPS'.

So I tried using a media converter to just change the frame rate to 30 fps (nothing else - still Quicktime MPEG4 AVC mov file).

And hey presto - the video is fine. I can step back without an issue, and nothing untoward in the message log.

The problem is that the Casio Exilim only saves as the 29.970 MOV file, so I would have to get my students to convert the file to 30fps every time they wanted to analyse anything. Can Tracker address this issue?

Cheers,
Steve


Current Replies - View all
Re: Video freezes on step...   (Douglas Brown - Aug 1)
Re: Re: Video freezes on ...   (Steve Draper - Aug 2)
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