Dalsa PC-30-02K80-R, Руководство пользователя

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Piranha Color Camera User’s Manual 37
DALSA 03-032-10211-03 9/27/2007
Notes: •
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).
Example:
sah 2
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 Processing
Digital Processing
analog video
analog
gain
analog
offset
FPN
coefficients
digital
offset
PRNU
coefficients
background
subtract
digital system
gain
sag,ccg
sao
ccf
sdo
ccp,cpa ssb
ssg
background
addition
digital video
sab
background
addition
digital video
eil
LUT
addition