1 Topic by DoublePar

  • DoublePar
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I'm recording a golf swing. I'm using a microphone to trigger the recording. I have two instances of Kinovea running, one with two recording windows and the other with two playback windows.

The recording settings are identical, using identical cameras with identical settings.

The recordings are saved to two different folders and the "Playback Instance" automatically plays back from the respective folders. Its configured to playback using motion synchronization.

What I'm experiencing is that the videos seemingly start synchronized but become noticeably unsynchronized about 55% through the playback and becomes further unsynchronized with one recording finishing before the other.

I can't figure out what i need to do to synchronize the videos throughout playback.

2 Reply by joan

  • joan
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Is it specifically about the motion synchronization option? I haven't worked on this mode for a while and it was experimental, I'm not sure it works very well. I do think it's an interesting feature to have but it might be broken right now.

I don't think this mode is documented at all, what made you select it?

To recap, the motion synchronization mode is intended to be a two-point synchronization. Instead of synchronizing the videos on one event it synchronizes on both a start and an end point, and forces one of the video to run in slow motion. The end point is based on the end of the working zone.

In the context of golf you could place the start point (normal sync point via time origin) at the very begin of the swing and the end point (end of working zone) at impact or at the end of the follow-through.

This requires manually setting the start and end point so in an automated capture and replay context I'm not sure it is that useful. With audio trigger the main sync point should be at impact in each video instead of the start of the swing. Maybe you didn't mean to use this mode in the first place?