Dalsa Piranha ES Series, Руководство пользователя

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Piranha ES-xx User Manual
03-032-20070-02 Teledyne DALSA
64
PRNU Correction
Performing PRNU Correction
Pu rp ose: Perform s PRN U correction to a cam era calibrated p eak 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. For a com p lete
d escrip tion on how to u se this com m and , see the Flat Field
Correction Overview on p age 58.
Syntax
ccp
N otes:

Perform all analog ad ju stm ents before calcu lating PRN U.

Perform FPN correction before PRN U correction .

If FPN cannot be calibrated , u se the
rpc
com m and to reset all
coefficients to zero, and save them to m em ory w ith the
wpc
com m and . You can then ad ju st the d igital offset (
sdo
com m and ) to rem ove som e of the FPN .

The
ccp
com m and is not available w hen the cam era shift
d irection is externally controlled . Direction control m u st be
stable w hile the cam era is calcu lating coefficients (see
Direction Control on p age 26).

Ensu re cam era is op erating at its exp ected analog gain,
integration tim e, and tem p eratu re.

To avoid losing you r cu rrent d irection coefficients, you m u st
save the PRN U coefficients u sing the com m and
wpc
before
changing cam era shift d irection or changing from TDI to
Area Mod e.

Available in TDI Mod e only.

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 p ixel coefficients are d isabled
(ep c 0 0) d u ring the algorithm execu tion bu t retu rned to the
state they w ere p rior to com m and execu tion.
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 th e 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 p ixel coefficients are d isabled (ep c 0 0) d u ring the
algorithm execu tion bu t retu rned to the state they w ere p rior to
com m and execu tion.
Syntax:
cpa i i
Syntax Elem ents:
i
PRN U calibration algorithm to u se:
1
= This algorithm first ad ju sts each tap ’s analog gain so that 8-
13% of p ixels w ithin a tap are above the valu e sp ecified in the
target valu e p aram eter. PRN U calibration then occu rs u sing the
p eak p ixel in the region of interest.
This algorithm is recom m end ed for u se only w hen FPN is
negligible and FPN coefficients are set to zero. Since this