XIIMUS R-GB-IR CL User Manual. Version 1.2
In order to remove unevenness of the lighting profile and lens curvature along the vector at
the same time as when performing white balancing, each individual pixel along the vector
needs to be scaled to the corresponding infrared maximum value (L1). Now, in this case, in
order for the line profile on all colour channels to equal line L1, the infrared channel line also
has to be scaled. Thus, at the beginning of the infrared line, the lowest pixel value at level L2
has to be multiplied with a multiplier
IR
x
, so that it equals line L1. Accordingly, at the start of
the bluegreen channel line, the line L3 has to match line L1 for the camera to be in white
balance.
As illustrated in fig. 4.4, the bluegreen channel will have the largest multipliers and the centre
of the infrared channel line will have multipliers close to unity. Also, the far ends of each
colour channel will have the largest multipliers of the colour channel in question.
Figure 4.4.
Correction in the direction of the vector.
© TVI Vision, 18 October 2006 page 15 ( 57 )
