Baumer TXG - Look-Up-Table; Gamma Correction

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4.1.4 Look-Up-Table
The Look-Up-Table (LUT) is employed on Baumer monochrome cameras. It contains 2
12
(4096) values for the available levels of gray. These values can be adjusted by the user.
In this example the LUT is used to overwrite levels of gray which are not of interest or in
the case of overdrive.
4.1.5 GammaCorrection
With this feature, Baumer TXG cameras offer the possibility of compensating nonlinearity
in the perception of light by the human eye.
For this correction, the corrected pixel intensity (Y') is calculated from the original intensity
of the sensor's pixel (Y
original
) and correction factor γ using the following formula (in over-
simplied version):
Y' = Y
original
γ
On Baumer TXG cameras the correction factor γ is adjustable from 0.001 to 2.
The values of the calculated intensities are entered into the Look-Up-Table (see 4.1.4.).
Thereby previously existing values within the LUT will be overwritten.
Notice
If the LUT feature is disabled on the software side, the gamma correction feature also
is disabled.
H
E0
▲Figure34
Non-linear perception of
the human eye.
H - Perception of bright-
ness
E - Energy of light