JAI BB-141GE, Руководство пользователя

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BM-141GE / BB-141GE
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9.3.3 Programmable Look UP table (LUT)
BM-141GE/BB-141GE has a programmable look-up table (LUT) that can be used to adjust the
transfer function of the video output. In other words, LUT can be used to create a user
defined Knee of Gamma function. In order to get a desired set of characteristics, LUT Values
should be set at each LUT Index (0 to 255). For instance, if the gamma is set to 0.45, LUT
Value in the dark portion should be high and it should be smaller as the signal level becomes
high. Please refer to the following drawing.
Fig. 27 LUT default setting (Coefficient: x1.0=4096)
The LUT consists of a data table of each gain which corresponds to all possible CCD outputs. T
In the Control Tool, each LUT Value is displayed as a coefficient (actual LUT value/4096).
Signals multiplied by these LUT coefficients create the desired output signal characteristics.
The look up table has 256 setting points of 14 bits covering the full range of input signals. On
each point, the gain can be set to get desired output characteristics. Gr, R, Gb and B signals
in BB-500GE have the same characteristics.
The Look Up Table is handled in a 14-bit Video Process circuit and a processed signal is output
as a 8-,10- or 12-bit pixel format through GigE interface.
Fig.28 Setting example of Gamma=0.45
(X4.0)
(X3.0)
(X2.0)
(X1.0)
(X0.5)
(X0.25)
LUT Value
(Coefficent)
0
255
LUT Index (D000 to D3FC)
1024
2048
4096
8192
16384
Video Inout
V
id
eo
o
ut
pu
t
Gamma=1 (OFF)
Γ
Look Up Table Default setting Video IN/OUT characteristics
CCD Out
Video Process
14-bit
GigE Interface
Pixel format
8-bit, 10-bit, 12-bit
(X4.0)
(X3.0)
(X2.0)
(X1.0)
(X0.5)
(X0.25)
LUT Value
(Coefficent)
0
255
LUT Index (D000 to D3FC)
1024
2048
4096
8192
16384
Video Inout
V
id
eo
o
ut
pu
t
Gamma=0.45 (OFF)
Look Up Table γ=0.45 setting Video IN/OUT γ=0.45 characteristics