Kaya Instruments IRON SDI 265, User Manual

Page: 29 / 30

Page no. 27 | Appendix No. 1
10.4 Brightness Level
The Desired Brightness Level reflect the average value of all pixels in the defined ROI. The value range of the
Desired Brightness Level depends on the output pixel bitness. e.g for 10bit output the value should be between 0
and 1023, while for 12bit output the value should be between 0 and 4095.
Figure 18 – Setting desired brightness
The average value is calculated by the following formula:
𝑎𝑣𝑔_𝑣𝑎𝑙 =
ExposureAutoRatio
[
red
]
∗ 𝑎𝑣𝑔_𝑣𝑎𝑙[𝑟𝑒𝑑]
+ ExposureAutoRatio
[
green
]
∗ 𝑎𝑣𝑔_𝑣𝑎𝑙[𝑔𝑟𝑒𝑒𝑛]
+ ExposureAutoRatio
[
blue
]
∗ 𝑎𝑣𝑔_𝑣𝑎𝑙[𝑏𝑙𝑢𝑒]
max_𝑣𝑎𝑙 =
ExposureAutoRatio
[
red
]
∗ max_𝑣𝑎𝑙[𝑟𝑒𝑑]
+ ExposureAutoRatio
[
green
]
∗ max_𝑣𝑎𝑙[𝑔𝑟𝑒𝑒𝑛]
+ ExposureAutoRatio
[
blue
]
∗ max_𝑣𝑎𝑙[𝑏𝑙𝑢𝑒]
𝑟𝑜𝑖_𝑎𝑣𝑔 =
BrightnessLevelAveragePeakBalance
∗ 𝑎𝑣𝑔_𝑣𝑎𝑙
+ (1 −
BrightnessLevelAveragePeakBalance
) ∗ max_𝑣𝑎𝑙
The algorithm strives to make roi_avg value as close as possible to the specified “DesiredBrightnessLevel” by
changing Exposure and Analog Gain. Current average value and maximum value can be retrieved using
“AverageBrightnessLevel” and “PeakBrightnessLevel” parameters.
Parameter Description Gen<i>Cam name Type Possible values Remarks
Value Gen<i>Cam name
Gen<i>Cam Category: AnalogControl
Desired
Brightness Level Desired brightness level for
auto compensation algorithm DesiredBrightnessLevel Integer Range: 0 to
<max pixel
value>
Average
Brightness Level Current average brightness
level result from auto
compensation AverageBrightnessLevel Integer Range: 0 to
<max pixel
value>
Peak Brightness
Level Current peak brightness level
result from auto
compensation PeakBrightnessLevel Integer Range: 0 to
<max pixel
value>
Brightness Level
Average Peak
Balance Sets the effective ratio of
Average Brightness Level as
complement to Peak
Brightness Level BrightnessLevelAveragePeakB
alance
Float Range: 0 to 1 1 - Complete
Average Level and
0 - Complete Peak
Level
Auto Exposure
Ratio Selector Selects which Exposure Auto
compensation ratio to control ExposureAutoRatioSelector Enumeration 0x00 Red
0x01 Green
0x02 Blue