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Issue #1 - Calibration
Calibration results tend to be random. I use 4 PS cams, and I've set them up in several alignments, from 160* to 250*, made calibration capture in both calibration mode and not, in both total darkness and normal light, from 25 to 50 fps, 320x240 to 640x480, I've marked from 3 to 7 groundpoints but results didn't improve any way or combination I tried. I got somewhat accurate camera placement in about 10% of the cases randomly spread, so no combination of cam placement, light, fps, resolution or number of groundpoints has given better results than another.
Almost every time 1 or more cams end up BELOW ground level, which has to be viewed as a BUG. Negative values on height shouldn't be possible.
I've resorted to measuring cam positions on x,y,z axis from the designated center before I begin caption and these values I enter in the XML scenefile and I get acceptable results after several adjustments to get the angles right. Not perfect and timeconsuming but seems it's only thing that works for me.
I wonder if changes could be made to the calibration so that it's enough to mark 4 points:
1 - center (on groundplane);
2 - 1m in front of the center (also ground);
3 - 1m left/right of center (ground);
4 - 1m straight above the centerpoint.
This should give the software both the xyz axis aswell as a scale to work from and place the cameras correctly using 4 frames rather than chewing hundreds of frames.
Issue #2 - Tracking
I'm aware that with less than perfect calibration that results won't be awesome, but while first few frames tend to be somewhat aligned, very quickly legs get crossed or arms twist backwards in odd angles. Manually adjusting and correcting is timeconsuming and only helps for a few frames before one or more limbs go astray again.
Regards,
Liviu
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