How to get TIME?

[alex_karate_do]

Hi,
I'm a student of the University of Tor Vergata, Rome.
I'm doing my degree thesis in mechanical engeneering using the V100 cameras and the Rigid Body software and API (C++).
I'd like to know if it is possible to get the exact time between two frames captured by the cameras, because I noticed that it is not always 100 frame per second. I need this information because I have to calculate the speed of a rigid body using a c++ program, written using the API.

Another question: i've noticed that there is an Optitrack API called INPSmoothing; can I use it to reduce the noise in the captured coordinates of the rigid body?

Thanks for your attention,
Alex

[beckdo]

Hey Alex,

You should be able to get every frame coming from the API which would leave you, for all intents and purposes, with precisely 100 FPS. If your application does not call GetFrame() often enough, you will drop frames which will cause problems for your speed calculation.

[beckdo]

Yes, INPSmoothing can be used. There should be some documentation on this in the OptiTrack SDK manual.

[Jim]

Hello:

The cameras will be running at exactly 100 FPS, but the frame delivery could be different as there is USB latency. As Doug suggests, if you capture all frames, then it is safe to assume you have exactly 100 FPS.