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Piranha Color Camera User's Manual
The brightest pixel should be slightly below the target output.
When greater than 6.25% of the pixels from a single row within the region of interest
are clipped, then flat field correction results may be inaccurate.
Correction results are valid only for the current analog gain and offset values. If you
change these values, it is recommended that you recalculate your coefficients.
Set up the camera operating environment
(i.e. line rate, exposure, offset, gain, etc.)
Set the calibration sample size using
the command css. It is recommended that
you use the default setting.
Set the region of interest to include all
of the image's pixels of importance using
the command roi x1 y1 x2 y2. You can use
the default if you want to calibrate all pixels.
Perform FPN calculation
Perform PRNU calculation
FPN Measurement
Performing FPN Measurement
Purpose:
Syntax:
Notes:
DALSA
Digital offset and digital system gain, and background subtract and
add values should be set to zero (
1. Stop all light from entering the camera. (Tip: Cover lens with a lens cap.)
2. Verify that the output signal level is within range by issuing the command
gl
or
gla
. If there are too many zeros in the output data (more than 6.25%
of output data within the roi) , increase the analog offset (
automated algorithm
cao 0
i
. If the average of the pixels is too high for your
application, reduce the analog offset or gain level (
3. Issue the command . The camera will respond withOK> (if no error occurs).
FPN calculation automatically calibrates FPN coefficients and digital offset.
4. After the calibration is complete, you should save these settings to non‐volatile
memory so they be reusable on reboot. To do so, issue the commands
wus
.
5. To verify output, enable the FPN coefficients using the command
You should see close to zero output.
Perform PRNU calculation next to determine the multiplication
factors required to bring each pixel to the required value (balance target) for
flat, white output.
1. Place a white reference in front of the camera.
2. Verify that the output signal level is within range by issuing the command
or
gla
. If the signal level is too low, increase your light level, adjust the analog
gain (
sag
) or use the automated algorithm
DALSA recommends a target value of about 80% of saturation. If you change
the gain, FPN coefficients should be recalculated.
3. Issue the command
ccp
. The camera will respond with OK>( if no error occurs).
4. After the calculation is complete, you can save these settings to non‐volatile
memory so they will be remembered after power‐down and direction change.
To do so, issue the commands
5
. Enable the coefficients using the command,
Measures fixed pattern noise (FPN).
ccf
•
Before sending this command, use the
03-032-10211-03
ssb 0 0sdo 0 0ssg 0 0sab 0 0
,
,
,
sao
) or use the
sag
).
ccg i 0 i
.
wpc
and
wus.
epc 1 1
.
scl
44
)
wfc
and
epc 1 0
.
gl
command to
9/27/2007
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