Piranha4 8K Color Camera User's Manual
53
Teledyne DALSA
03-032-20156-02
1. Flat Field
This Flat Field set contains a nu m ber of featu res that are u sed to correct im age d istortion d u e to lens
vignetting and u neven illu m ination . .
Note
:
1.
Flat field coefficients consist of an offset and gain for each p ixel.
2.
These are the first u ser corrections ap p lied to the im age .
3.
The flat field coefficients are saved and load ed w ith the u ser set.
Parameter
Description
flatfield CorrectionMod e
1.
Off – Flat field correction coefficients are not ap p lied .
2.
On – Flat field correction coefficients are ap p lied .
3.
Initialize – Send ing this valu e w ill reset all cu rrent coefficients
(offsets to 0 and gains to 1x).
flatfield CorrectionAlgorithm
1.
Basic – Direct calcu lation of coefficients based on cu rrent
average line valu es and target.
2.
Low Pass – A low p ass filter is first ap p lied to the cu rrent
average line valu es before calcu lating the coefficients. Use this
algorithm if the calibration target is not u niform w hite or it s
not p ossible to d efocu s the im age. Becau se of the low p ass filter
this algorithm is not able to correct p ixel-to-p ixel variations and
so it is p referable to u se the ―Basic‖ algorithm if p ossible.
flatfield CalibrationTarget
1.
After calibration all p ixels w ill be scaled to ou tp u t this level
Range: 8 bit, 0 to 255 DN
flatfield CalibrationSam p leSize
1.
N u m ber of lines to average w hen calibrating
2.
2048 or 4096
flatfield Calibration ROIOffsetX
1.
Together with ―flatfield Calibration ROIWid th‖ specifies the
range of p ixels to be calibrated . Pixel coefficients ou tsid e this
range are not ch anged . It is p ossible to calibrate d ifferent
regions sequ entially.
flatfield Calibration ROIWid th
flatfield CalibrationFPN
1.
Save average line (of ―flatfield CalibrationSam pleSize‖ rows).
This is the first u ser correction ap p lied – it is su btracted from
each line.
2.
This featu re m ay not be of u se to m any u sers as the cam era
alread y su btracts tru e ―d ark cu rrent‖, bu t it m ay be u sefu l for
som e to p rovid e a p er p ixel offset correction.
3.
Range 0 to 31 DN , 8 bit
4.
Defau lt valu e is 0 DN for each p ixel
flatfield CalibrationPRN U
1.
Use ―flatfield CorrectionAlgorithm ‖ to calculate the per pixel
gain to ach ieve the sp ecified target ou tp u t.
2.
Max 15.9998x
3.
Defau lt 1x
