Optronis CP80-4-M/C-500, Руководство пользователя

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CP80-4 ; CP90-4 Ref. 1887-SU-01-H Page 42
W = width and H = height.
Grab a sequence of 100 frames in the dark (with full resolution). Build an average frame D with
these 100 frames.
With the average frame, build an horizontal profile DP, i.e.:
For each x (column), DP(x)=[D(x,0)+...+D(x,H-1)]/H
Open the aperture of the lens to allow light and then capture
the grey frame. All the pixels in the grey image should have a
grey value of approximately 70% white (histogram should
peak at 70% white and the distribution should be uniform
around the peak as much as possible). Store a sequence of 100 frames
and build an average frame G. Then build an horizontal profile:
For each x (column), GP(x)=[G(x,0)+...+G(x,H-1)]/H
A generic formula is defined to correct FPN and PRNU:
CORR(x,y) = UserGG(x)*(Uncorr(x,y)-DP(x)) + Avg(DP) + UserGD,
where:
UserGG(x) : factory initialized to ([Avg(GP)-Avg(DP)] / [GP(x) - DP(x)])
CORR(x,y) : data of a pixel after a calibration
UNCORR(x,y) : data of a pixel before carrying out a calibration
DP(x) : black calibration data of the column x
GP(x) : grey calibration data of the column x
UserGD : user global dark offset fine adjustement between 0 and 127
FPN Correction Only
1) Proceed to the dark frame acquisition as described previously.
2) Launch CXP_Flash to start the camera upload program with the USB cable connected to the
camera.