Spyder3 SC-34 Color Camera User's Manual
39
Teledyne DALSA
03-032-20116-01
Analog Signal Processing
Black Level Offset Algorithm : Inherent to the A/ D is an offset that is ad d ed to the vid eo in ord er to
elim inate vid eo clip p ing in d ark (the offset is also affected by tem p eratu re). The Sp yd er 3 Color Cam eras
have an au tom atic su btraction of this offset, w hich is called the Black Level Offset Algorithm . This
su btraction help s p revent any u nw anted color shift . For exam p le, if the offset is 15 DN in 12-bit
m u ltip lying by m ax gain (20 d B) w ill give 300 DN (12-bit) offset in the final valu e. With Black Level
Offset d igital gain only affects the color signal and not the u nd erlining analog offset. The sole job of the
Black Level Offset Algorithm is to keep the offset arou nd 0 DN regard less of analog offset setting or the
change in d ark cu rrent (tem p eratu re). 0 DN offset is d esirable becau se you d o not w ant you r color gains
changing you r offsets for each color .
Digital Signal Processing
To op tim ize cam era p erform ance, d igital signal p rocessing shou ld be com p le ted after any analog
ad ju stm ents.
FPN Correction
Performing FPN Correction
Syntax:
Perform s FPN correction and elim inates FPN noise by rem oving ind ivid u al p ixel d ark
cu rrent.
Syntax:
ccf
N otes:
Perform all analog and d igital ad ju stm ents before p erform ing FPN correction.
Perform FPN correction before PRN U correction.
Refer to p age 36 for a p roced u ral overview on p erform ing flat field correction.
To save
FPN coefficients after calibration, u se the w fc com m and . Refer to section 3.10 Saving
and Restoring PRN U and FPN Coefficients for d etails.
Related Com m and s:
wfc
Exam p le:
ccf
PRNU Correction
Performing PRNU to a user entered value
Pu rp ose:
Perform s PRN U calibration to u ser entered valu e and elim inates the d ifference in resp onsivity
betw een the m ost and least sensitive p ixel, creating a u niform resp onse to light. Using this
com m and , you m u st p rovid e a calibration target.
Execu ting these algorithm s cau ses the
ssb
com m and to be set to
0
(no backgrou nd su btraction)
and the
ssg
com m and to
4096
(u nity d igital gain). The pixel coefficients are d isabled (
epc 0 0
)
d u ring the algorithm execu tion bu t retu rned to the state they w ere in p rior to com m and execu tion.
Syntax:
cpa
i i
Syntax Elem ents:
i
PRN U calibration algorithm to u se:
2
= Calcu lates the PRN U coefficients u sing the entered target valu e as show n below :
PRNU Coefficient =
Target
(AVG Pixel Value )
i
i
All manuals and user guides at all-guides.com