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Proprietary to OmniVision Technologies
Version 1.1, December 7, 2004
OV9650 Color CMOS SXGA (1.3 MegaPixel) CameraChip™
O
mni
ision
5.1.1 Gamma Slope Calculation
The Gamma Slope is determined by following equation:
To normalize the real number (Gamma Slope) to an 8-bit decimal value, the OV9650 applies 64 as
a normalize factor as shown below:
GST7
0x82
GSP8
0x73
XREF8
64
GST8
0x83
GSP9
0x74
XREF9
72
GST9
0x84
GSP10
0x75
XREF10
80
GST10
0x85
GSP11
0x76
XREF11
96
GST11
0x86
GSP12
0x77
XREF12
112
GST12
0x87
GSP13
0x78
XREF13
144
GST13
0x88
GSP14
0x79
XREF14
176
GST14
0x89
GSP15
0x7A
XREF15
208
GST15
0x8A
GSP16
0x7B
Note:
GST(0) =0, GST(16) = 255, XREF(0) =0, XREF(16) = 255.
Note:
Gamma Start Point and Slope should be matched; otherwise,
there will be discontinuous points in the Gamma curve.
Table 5-1.
Related Registers and Parameters (Sheet 2 of 2)
Gamma Start Point
Gamma Slope
Horizontal Reference
Name
Register
Name
Register
Name
Value
XREF(i) -XREF(i-1)
GST(i) - GST(i-1)
Gamma Slope(i) =
XREF(i) -XREF(i-1)
GST(i) - GST(i-1)
GSP (i) = Gamma Slope(i)
×
64 =
×
64