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Piranha Color Camera User's Manual
Notes:
Example:
3.13 Processing Chain Overview and
Description
The following diagram shows a simplified block diagram of the camera's analog and
digital processing chain. The analog processing chain begins with an analog gain
adjustment, followed by an analog offset adjustment. These adjustments are applied to
the video analog signal prior to its digitization by an A/D converter.
The digital processing chain contains the spatial correction, non-linearity look-up table
(LUT) correction, FPN correction, the PRNU correction, the background subtract, the
digital gain, and the background add. All of these elements are user programmable.
Figure 7: Signal Processing Chain
analog video
DALSA
•
Selecting sah 1 results in no averaging.
•
Selecting sah 2 averages pairs of pixels: (P1+P2)/2,
(P3+P4)/2, (P5+P6)/2...
•
If you are using averaging, the minimum, maximum, and
mean statistics generated by the gl or gla commands and
used by the ccg, cao, ccf, and ccp commands are for the
un-averaged pixels.
•
Changing the averaging does not require the recalibration
(analog gain, FPN or PRNU) of the camera.
•
The current value of horizontal averaging factor can be
obtained using the gcp or get sah commands.
•
Horizontal averaging does not affect the CCD readout time,
but it does affect FIFO readout as all the pixels still need to
be read out of the CCD, but only the averaged pixels stored
in the FIFO (line store).
•
ROI will be pushed out to include both averaged pixels at
each end (e.g. if the ROI was 4-2048, the start value would
be changed to 3, since the first averaged pixel consists of
sensor pixels 3 and 4).
sah 2
Analog Processing
analog
analog
LUT
offset
gain
addition
sag,ccg
sao
03-032-10211-03
Digital Processing
PRNU
coefficients
eil
ccp,cpa
digital
offset
sdo
FPN
coefficients
ccf
37
digital system
background
background
background
gain
addition
addition
subtract
ssg
sab
ssb
9/27/2007
digital video
digital video
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