Dalsa Piranha3, User Manual

Page: 78 / 91

Piranha 3 User Manual
03-032-10216-02 DALSA
78
Command Syntax Parameters Description
calculate PRNU
algorithm
cpa
i i
Performs PRNU calibration according to
the selected algorithm.
The first parameter is the algorithm
where
i
is:
1
= This algorithm first adjusts each tap’s
analog gain so that 8-13% of pixels
within a tap are above the value specified
in the target value parameter. PRNU
calibration then occurs using the peak
pixel in the region of interest. (Identical
to
ccp i
)
2
= Calculates the PRNU coefficients
using the entered target value as shown
below:
PRNU Coefficient =
Target
(AVG Pixel Value) - (FPN+ value) sdo
The
calculation is performed for all sensor
pixels but warnings are only applied to
pixels in the region of interest. This
algorithm is useful for achieving uniform
output across multiple cameras.
3
= This algorithm includes an analog
gain adjustment prior to PRNU
calibration. Analog gain is first adjusted
so that the peak pixel value in tap’s ROI
is within 97 to 99% of the specified target
value. It then calculates the PRNU
coefficients using the target value as
shown below:
PRNU Coefficient =
Target
(AVG Pixel Value ) ‐ (FPN + value)
sdo
i i
i
The calculation is performed for all
sensor pixels but warnings are only
applied to pixels in the region of interest.
This algorithm is useful for achieving
uniform output across multiple cameras.
The second parameter is the target value
to use in a range from
1024
to
4055
DN.
section 3.4.2 Analog and Digital Signal
Processing Chain
4 = This algorithm is the same as 2 with
the exception that it only calculates
PRNU for the pixels within the current
Region of Interest (ROI).
The second parameter is the target value
to use in a range from
1024
to
4055
DN.
correction set sample
css m
Set number of line samples averaged for
pixel coefficient calculations or for
output of
gla
command. Values:
256
,
512
,
1024
.
Refer to Returning Averaged Lines of
Video on page 55 for details.