Data drift

[Candive]

I can't explain why there is a drift in your videos. Perhaps someone can provide an explanation. It even could be computer hardware related - some type of buffering from the graphics card which lags the video; who knows? And maybe you found something that others weren't aware of in their own racing videos since they didn't record their feet. If you hadn't videotaped the driver's feet, would you be aware of the drift?

Regardless, if any of the above suggestions work or you find a unique solution, please post it back here so that others may benefit from your knowledge.

Thanks.

[Armaki]

Thanks for your ideas. You could still "see" the drift by the engine sound or the gear indicator, but that's too detailed. I will check your suggestions and keep the thread updated.
Cheers

[Armaki]

I think I found a way around the drift problem.

1) Sync the data at the beginning, Mark the offset.
2) jump to the end and sync again. Mark the offset again.
The difference between the offsets (~-0,3sec in 30minutes for the case I tried) , over the total duration is the play speed factor correction needed
Ex:. -0,3/1800= -0.000016. Means a play speed of 0.999983.

The problem though is synchronisation at the end because of severe lagging on big videos. The way around that is to create a dummy project, after synchronizing at the beginning, containing only the data and a reference video. Once you define the factor, you just carry the number to the main project.
So far I can live with that, but again, sound wave synchronisation would be a big plus (hint hint hint)

Thanks for your ideas though!