rainers proposal for pearson coefficient of complex data
a few important notes in particular reflection of camera data
read the femtolisp system definition with read-from-string, preserve the case
i used a loop on the arduino to obtain full frame rate ~45fps
issuing each trigger command individually to the camera only allows 38fps
the camera has an enumration:
LastError that tells me about missed triggers
i think i obtain full frame rate with triggering now
i should implement command execution to clear errors on the camera
i can reset the timestamp counter now. data acquisition looks like this:

Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1 fnr=1 ts=14915973 id=348 inr=1 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 2

Camera 2: Basler acA1920-25gm#00305315DFC4#192.168.6.101:3956
GrabSucceeded: 1 fnr=1 ts=16620362 id=344 inr=1 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 1

Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1 fnr=2 ts=17670655 id=349 inr=2 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 1

Camera 1: Basler acA1920-25gm#00305315DFDE#192.168.5.102:3956
GrabSucceeded: 1 fnr=1 ts=15794898 id=340 inr=1 skip=0
SizeX: 580
SizeY: 580
Gray value of first pixel: 9

Camera 2: Basler acA1920-25gm#00305315DFC4#192.168.6.101:3956
GrabSucceeded: 1 fnr=2 ts=19375043 id=345 inr=2 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 2

Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1 fnr=3 ts=20425336 id=350 inr=3 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 1

Camera 1: Basler acA1920-25gm#00305315DFDE#192.168.5.102:3956
GrabSucceeded: 1 fnr=2 ts=18471220 id=341 inr=2 skip=0
SizeX: 580
SizeY: 580
Gray value of first pixel: 5

Camera 2: Basler acA1920-25gm#00305315DFC4#192.168.6.101:3956
GrabSucceeded: 1 fnr=3 ts=22129725 id=346 inr=3 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 1

Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1 fnr=4 ts=23180017 id=351 inr=4 skip=0
SizeX: 512
SizeY: 512
Gray value of first pixel: 2
i have to test how fast the image processing can really run