Topic: Version 0.8.24 issues with exported data
I've used Kinovea for some time now to estimate burst swim speeds of fish in lab trials. I've recently started using a GoPro to do the filming and have thus tried the distortion correction available in this latest version (by importing a calibration file from Agisoft lens). The calibration seems to work quite well but I'm having an issue with the exported data. Specifically:
1. In the exported data, the time stamp is shifted by four rows relative to the x,y values. So the first x,y coords of a track will have a time stamp which is four frames later.
2. If I correct this manually and then calculate speed, I'm not getting the same thing as what is shown using the display measure tool. I thought this maybe had to do with rounding error of the time value as its available in many formats. But even if I use what would be the most precise, microsec, I still don't get the same value. So I'm not sure what's going on here. here's an example:
Speed (cm/s) estimated using different time formats for a few point at random
mm:milsec total milsec total micsec display measure
88.0 110.0 105.5 99
5.4 6.8 6.5 8