VT Camera Link series
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VW40-161-001
9.10
Photo Response Non-uniformity Correction
In theory, when a line scan camera acquires images with the camera viewing a uniform light-colored target in
bright light, all of the pixel values in the image should be near the maximum grey value and they should be
equal. In practice, however, slight variations in the performance of the pixels in the sensor, variations in the
optics, and variations in the lighting will cause some variations in the pixel values output from the camera. This
variation is known as Photo Response Non-uniformity (PRNU). The VT Camera Link cameras provide the PRNU
Correction feature and five storage locations for PRNU correction values.
The commands related to PRNU are as follows.
Configurator Parameters
Command
Value
Description
PRNU Correction
sprnu 0
Off
Disables the PRNU Correction feature.
sprnu 1
On
Enables the PRNU Correction feature.
PRNU Selector
spi 0, 1, 2, 3, 4
0/1/2/3/4
Selects a location to save PRNU data to or load
PRNU data from.
Auto
gpd 0
-
Select to set the PRNU Target Level automatically.
Target
-
1 ~ 255
Sets the PRNU Target Level.
Generate
gpd n
0 ~ 255
Generates the PRNU data.
0: Auto, 1 ~ 255: Sets the PRNU Target Level.
Save to Flash
spd
-
Saves the generated PRNU data in the non-
volatile memory.
The generated data by executing the
Generate
command are saved in the volatile
memory so that the data are lost if the camera
is reset or if power is turned off. To use the
data after the camera is powered on or rest,
save them in the non-volatile memory.
Load from Flash
lpd
-
Loads the PRNU data from the non-volatile
memory into the volatile memory.
Table 9.14 Commands related to PRNU
Summary of Contents for VT Series
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