1 Topic by bantandor

  • bantandor
  • Member
  • Offline

Hello,
Firstly, I really would like to thank you for the software you have been developing. It took me 20 min. to figure out how it works, user friendly. I have couple of questions. What I am trying to measure is that when subjects walk on the treadmill there is a displacement of center of mass. We are planning to get recording of a subject from frontal plane with one camera while they are walking on the treadmill. We will place a 100 cm calibration band on the subject and a marker on the center of mass located at S2 vertebrae. But, subject will go front and back during walking and the 100 cm calibration line will shrinks and grows as he moves, thus there will be an error in measuring displacement (parallax error). How Kinovea can overcome this situation. Is it possible to use two cameras simultaneously (one at frontal and one at saggital plane) to fix or minimize the parallax error with Kinovea? Or there are other solutions?

Thank you
Taner ERDOGAN

2 Reply by joan

  • joan
  • joan
  • Admin
  • Offline

Hello,
Currently there is no way to work around this kind of perspective issues.

Maybe later, when line tracking is in place, we could define a calibration segment and programmatically force it to keep the same size in pixels over the course of the video, by resizing the whole image around it… The range of applications of this would need to be assessed though. If someone can think of other scenario where this may be of interest ?
Thanks