Teledyne DALSA Piranha PC-30-02K60-00-R, Руководство пользователя, Страница: 36 / 96

Piranha Color Camera 36
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