Teledyne DALSA Piranha 2 P2-2x-01K40, Руководство пользователя

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35 Piranha 2 User’s Manual
03-032-00493-14 Teledyne DALSA
To calibrate the an alog gain:
Syntax:
cag t i
Syntax Elem ents:
t
Tap selection. Allow able range is 1 to 4, or 0 for all tap s.
i
Line average in a range d ep end ent on th e cu rrent cam era
d ata m od e setting:
8-bit: 64 to 251 DN
10 bit: 256 to 1007 DN
See section 3.11 Retu rning Vid eo Inform ation for m ore
inform ation on line averages
N otes:

This fu nction requ ires constant light inp u t w hile execu ting.

This com m and sets gain in uncalibrated m od e.
Related Com m and s: gla, gl
Exam p le: cag 1 156
3.14 How to Calibrate the Camera
Calibration Overview
This cam era has the ability to calibrate itself in ord er to rem ove non -u niform ity in the
im age. This vid eo correction op erates on a p ixel-by-p ixel basis and im p lem ents a tw o
p oint correction for each p ixel. This correction can red u ce or elim inate im age d istortion
cau sed by the follow ing factors:
Fixed Pattern N oise (FPN )
Photo Resp on se N on Uniform ity (PRN U)
Lens and light sou rce non -u niform ity
The tw o p oint correction is im p lem ented su ch that for each p ixel:
V
ou tp u t
= (V
inp u t
- FPN ( p ixel ) - d igital offset) * PRN U(p ixel)
w here V
ou tp u t
= d igital ou tp u t p ixel valu e
V
inp u t
= d igital inp u t p ixel valu e from the CCD
PRN U( p ixel) = PRN U correction coefficient for this p ixel
FPN ( p ixel ) = FPN correction coefficient for this p ixel
The calibration algorithm is p erform ed in tw o step s. The fixed offset (FPN ) is d eterm ined
first by p erform ing a calibration w ithou t any light. This calibration d eterm ines exactly
how m u ch offset to su btract p er p ixel in ord er to obtain flat ou tp u t w hen the CCD is n ot
exp osed .
The w hite light calibration is p erform ed next to d eterm ine the m u ltip lication factors
requ ired to bring each p ixel to the requ ired valu e (balance target) for flat, w hite ou tp u t.
Vid eo ou tp u t is set slightly above the brightest p ixel (d ep end ing on offset su btracted ).