Dalsa Spyder2 - Setting and Reading FPN Coefficients

32 Spyder2 User’s Manual
03-032-10091-06 Teledyne DALSA
lev el . Use the gl command to determine input level. If the signal level is too low or
too high, adjust analog gain using the command
sg.
3. The variance in light intensity across the target must not be more than 4 to 1. Because
the maximum per-pixel digital gain is 2x, the camera will not be able to compensate
for extremely non-uniform light.
These restrictions are all tested within the calibration algorithm and the camera will
report an informal message code if any of these conditions could not be met.
To perform a white light calibration:
1. Place a w hite refer ence i n fr ont of the camera.
2. Verify that output signal level is within range by issuing the command gl or gla
(valid range is 128-
254). If signal level is too low or too high, adjust the gain using the
command sg.
3. Instruct the camera to perform a white light calibration using the command ccp. The
camera will respond with OK> if no error occurs.
To perform a white light calibration with an analog gain value:
Use the ccp [i]
command. When the optional parameter is provided the analog gain
is adjusted to produce an average white pixel level that is equi v al ent to the par ameter .
This command sets the analog gain first to
i
before calculating the PRNU coefficients
range from 64 to 251DN for 8-bit data mode, and 256 to 1007DN for 10-bit data mode.
If value is left blank, current gain values are used.
4. After the calibration is complete, you can save these settings to non-volatile memory
so they w i ll be remembered after pow er -down. To do so, issue the command
wpc.
Returning Calibration Results and Errors
After calibration, you can retrieve the results using the command dpc. This function
returns all the pixel coeffi ci ents in the order FPN , PRN U, FPN , PRN U… The cam er a also
returns the pixel number with each coefficient.
To set a range for the returned coefficients provide an optional pixel start and end value:
Example: display pixel coefficient from pixel 10 to 20
dpc 10 20
The command gcp returns all other settings.
3.15 Setting and Reading FPN Coefficients
You can set or read an individual pixel’s FPN coefficient.
To set the FPN coefficient, use the command:
Sy n t ax :
sfc i i
Sy ntax Elements:
i
The pi xel number fr om 1 to the pixel count.