Dahua A5A21M/CG9, User Manual

Page: 35 / 48

35
Parameter Explanation
different types and the default value is 1.
The analog gain is preferentially enabled.
BlackLevelSelector
BlackLevelSelector is used to select the black balance channel.
BlackLevel is used to eliminate the impact of Sensor’s dark current. The dark
current is a phenomenon that the image brightness is a value greater than 0
when it is all black. By modifying the black level value, the brightness of the
channel can be more responsive to the actual image brightness. The setting
range is 0 ~ 255.

When BlackLevelAuto is set as Off, the fixed black level that the
algorithm minus is 1/4 of the value set in BlackLevel.

When BlackLevelAuto is set as Once, it will automatically set
BlackLevel for once according to the return value of sensor. Then it will
change to be Off.

When BlackLevelAuto is set as Continues, it will continuously set
BlackLevel according to the return value of sensor.
Black level will change when the temperature rises. It is recommended to
capture a more accurate black level when the temperature is constant.
BlackLevel
BlackLevelAuto
BalanceRatioSelector
Selects Red, Green or Blue channel to set white balance.
Adjusts the image color through adjusting R/G/B, in order to achieve a
highest color reproduction.
 When BalanceRatioSelector is set as Off, it represents manual white
balance mode. User can manually set Red, Green, Blue channel values
in BalanceRatio.
 When BalanceRatioSelector is set as Once, it represents auto white
balance mode for once. Auto white balance mode will operate for a
period and then stops according to the current scene. An algorithm for
searching gray region is used to find possible gray region in Bayer data.

When BalanceRatioSelector is set as Continues, it represents continuous
white balance mode.
White balance correction is only available for the color camera. White
balance of the mono camera defaults to 1.
BalanceRatio
BalanceWhiteAuto
Gamma
Gamma value setting.
It is a non-linear correction for image data to correct the non-linear response
of the monitor. The larger the Gamma value, the brighter the image.
The Gamma value setting range is 0
～
3.99998. The default value is 1 with
no Gamma process.