1 Topic by dduck13

  • dduck13
  • Member
  • Offline

I am a coach and player for a football team and like the Kinovea software except for the stop watch...is there anyway to make it go to 1/1000 or even 1/10000 seconds?  I use it to time quarterbacks release time and would like to get it a little more exact.  Thanks for listening and let me know if this is possible and if it could be done in the future.

2 Reply by joan

  • joan
  • joan
  • Admin
  • Offline

Hi,
Unless you have very high speed camera with more than 1000 frames per second, I think the limiting factor is the framerate of the video file (or the capabilities of the capture device).
When you shoot with a regular camera at, say 50 fps, the time resolution is 20ms. Each image is separated from the next one by this ammount, and you cannot get more accurate than that. Every timing you do can only be a multiple of this fundamental unit.

In that regard, displaying hundredth of seconds is already sometimes misleading, as the time measurements are really only as accurate as the frame rate. (In an early version, the last unit of the timecode display was the number of frames, which is more right, but less useful).
We could display microseconds, nanoseconds, but it will not be more accurate, just more misleading in my opinion.

There are cameras with more than 1000 fps though, I don't remember if this is nicely supported (up to 999fps should definitely be ok). I don't think 10000 fps capable device can be used for timing people (outside photofinish hardware that is).

3 Reply by dduck13

  • dduck13
  • Member
  • Offline

ok...I have another question...I have tried to use this program to time guys release times and the timer seems to do by incraments of .03 sec.  Is there a reason for this?  I have used another program before and it didn't do this and had up to the 1/10000 of a second.  Thanks

4 Reply by joan (edited by joan 2011-01-10 14:02:52)

  • joan
  • joan
  • Admin
  • Offline
dduck13 wrote:

ok...I have another question...I have tried to use this program to time guys release times and the timer seems to do by incraments of .03 sec.  Is there a reason for this?

That would point to a 30 fps file which is quite common. (1/30 = 0.033).

dduck13 wrote:

I have used another program before and it didn't do this and had up to the 1/10000 of a second.  Thanks

Unless the video really has 10000 images per second, it is an artifact of the program. We can add as many digit after the decimal point as we want, the precision will not be better than 1 / fps.
Please re-check and see that when you move from one frame to another, you don't have 1/10000 increments (you may have 4 digits after the decimal point, but it is not really relevant).