Dalsa PC-30-02K80, Руководство пользователя

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Piranha Color Camera User’s Manual 49
DALSA 03-032-10211-01 5/9/2007
0
= PRNU coefficients disabled
1
= PRNU coefficients enabled
Example:
epc 0 1
3.16 Digital Gain and Background Subtract
Setting Digital Offset
Purpose: Sets the digital offset. Digital offset is set to zero when you
perform FPN correction (
ccf
command). If you are unable to
perform FPN correction, you can partially remove FPN by
adjusting the digital offset.
Syntax:
sdo t i
Syntax Elements:
t
Tap selection. Allowable range is
1
to
4
depending on color
selected, or
0
for all taps.
i
Subtracted offset value in a range from
0
to
4095.
Notes: When subtracting a digital value from the digital video signal, the
output can no longer reach its maximum unless you apply digital
gain using the
ssg
command. See the following section for
details on the
ssg
command.
Related Commands:
ssg
Example:
sdo 0 100
Subtracting Background
Purpose: Use the background subtract command after performing a flat
field correction in order to improve your image in a low contrast
scene. This is useful for systems that process 8 bit data but want
to take advantage of the camera’s 12 bit digital processing chain.
You should try to make your darkest pixel in the scene equal to
zero.
Syntax:
ssb t i
Syntax Elements:
t
Tap selection. Allowable range is
1
to
4
depending on color
selected, or
0
for all taps.
i
Subtracted value in a range in DN from
0
to
4095
.
Notes: When subtracting a digital value from the digital video signal the
output can no longer reach its maximum. Use the
ssg
command to correct for this where:
ssg value =
max output value
max output value ‐ ssb value
See the following section for details on the
ssg
command.
Related Commands:
ssg
Example
ssb 0 800
In 8-bit Camera Link mode: If your scene has a minimum value
of 50 DN and a maximum of 200 DN, then to expand it to 0
DN and 255 DN, set the
ssb
command to
800
(50 x 16), and
the
ssg
command to
6990
(4096 / ((200 – 50) x 16)) x 4096).