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ANUAL
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7.5.2
Automatic Calibration
FFC Low Band Filter
(
FFCAutoTargetLevel
)
:
set the value for the User Target.
Read function : “
r lffw
”. Returns the Filter Interval size (from 0 to 255)
Write function : “
w lffw <value>
” : Set the Interval size for the filter (0 / 1 … 255)
0 : Disables the FFC Low Band Filter
1 to 255 : Set the interval size (+/- the value around the pixel) for the Low Band filter
When you can’t provide a moving Target to the Camera during the PRNU Calibration you can setup the FFC Low
Band Filter in order to remove the defect from the Target before calculating the FFC parameters. The Value set in
the FFC filter defined the size of the interval around each pixel : The Filter will replace each pixel value by the
average on the interval.
FPN/DSNU Calibration :
o
FPN Calibration Control
(
FPNCalibrationCtrl
) : Launch or abort of the FPN process for the Offsets
calculation
.
These commands are available in the CommCam “Flat Field Correction / Automatic
Calibration ” section :
Read function : “
r calo
” : Returns the FPN Calculation Process Status (0 if finished, 1 if
processing)
Write function :
“
w calo 1
” : Launch the FPN Calibration Process.
“
w calo 0
” : Abort the FPN Calibration Process.
o
FPN Coefficient Reset
(
FPNReset
) : Reset the FPN (Offsets) coefficient in Memory
.
This command is
available in the CommCam “Flat Field Correction / Manual Calibration ” section :
Write function : “
w rsto 0
” : Reset (set to 0) the FPN coefficients in memory. This doesn’t
affect the FFC User Memory Bank but only the active coefficients in Memory.
PRNU Calibration :
o
PRNU Calibration Control
(
FFCCalibrationCtrl
) : Launch or abort of the PRNU process for the
Gains calculation
.
This command is available in the CommCam “Flat Field Correction / Automatic
Calibration ” section :
Read function : “
r calg
” : Returns the PRNU Calculation Process Status (0 if finished, 1 if
processing)
Write function :
“
w calg 1
” : Launch the PRNU Calibration Process.
“
w calg 0
” : Abort the PRNU Calibration Process.
o
PRNU coefficient Reset
(
PRNUReset
) : Reset the PRNU
(Gains) coefficient in Memory
.
This
command is available in the CommCam “Flat Field Correction / Manual Calibration ” section :
Write function : “
w rstg 0
” : Reset (set to “x1”) the PRNU coefficients in memory. This doesn’t
affect the FFC User Memory Bank but only the active coefficients in Memory.
Some Warnings can be issued from the PRNU/FPN Calibration Process as “pixel Overflow” of
“Pixel Underflow” because some pixels have been detected as too high or too low in the
source image to be corrected efficiently.
The Calculation result will be proposed anyway as it’s just a warning message.
The Status Register is the changed and displayed in CommCam “Status” section :
Register status is detailed chap §6.3.3.
