Cheetah KAC Camera User Manual | Camera Link (CLF) Interface
October 1, 2019
Page
118
of
135
Rev 7.2
5.17.2 User Defined LUT
You can define any 12-bit to 12-bit transformation as a user LUT and upload it to the
camera using the configuration utility software. You can specify a transfer function to
match the camera’s dynamic range to the scene’s dynamic range. There are no limitations
to the profile of the function. The LUT must include all possible input values (0 to 4095)
Figure 75: Custom LUT.
5.18 Defective Pixel Correction
A CMOS imager is composed of a two-dimensional array of light sensitive pixels. In
general, the majority of the pixels have similar sensitivity, but some deviate from the
average pixel sensitivity. A defective pixel is one whose response deviates by more than
15% from the average response. In extreme cases, these pixels fixate as black or white
and are non-responsive to light. There are two major types of pixel defects: Defective and
Hot.
1.
Defective
. These are pixels whose sensitivity deviates more than 15% due to
fluctuations in the CMOS manufacturing process. During final camera testing at
the factory, inspection identifies and automatically corrects up to 1024 defective
pixels using defective pixel correction. Two types of defective pixels are possible:
a.
Dark pixels.
These are pixels with sensitivity lower than the sensitivity of
the adjacent pixels. In some cases, these pixels will have no response
(completely dark).
b.
Bright pixels.
These are pixels with sensitivity higher than the sensitivity
of the adjacent pixels. In some cases, these pixels will have full response
(completely bright).
2.
Hot.
These are pixels that in normal camera operation behave as normal pixels
(sensitivity equal to one of the adjacent pixels), but during long time integration
behave as a high intensity bright pixel. In some cases, pixels will have full
response (completely bright). During final camera testing at the factory,
inspection identifies and automatically corrects up to 8192 hot pixels using hot
pixel correction.
