Look-Up Table (Lut) And Gamma Function - AVT Pike Technical Manual

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Look-up table (LUT) and gamma function

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The AVT Pike camera provides sixteen (0-15) user-defined look-up tables
(LUT). The use of one LUT allows any function (in the form Output = F(Input))
to be stored in the camera's RAM and to be applied on the individual pixels
of an image at run-time.
The address lines of the RAM are connected to the incoming digital data,
these in turn point to the values of functions which are calculated offline,
e.g. with a spreadsheet program.
This function needs to be loaded into the camera's RAM before use.
One example of using an LUT is the gamma LUT:
There are two gamma LUTs (gamma=0.7 and gamma=0.45)
0.7
Output = (Input) and Output = (Input)
These two gamma LUTs are used with all Pike models.
Gamma is known as compensation for the nonlinear brightness response of
many displays e.g. CRT monitors. The look-up table converts the incoming
14 bit from the digitizer to outgoing up to 14 bit.
Output = f (Input)
Pike, gamma=0.45
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Figure 61: LUTs with gamma=0.45, gamma=0.7
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Pike, gamma=0.7
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Input
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PIKE Technical Manual V4.1.0
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