Balance White Auto - Basler ace acA640-90gm User Manual

10.9.5

Balance White Auto

Balance White Auto is the "automatic" counterpart to manually setting the white balance. The
balance white auto function is only available on color models.
Automatic white balancing is a two-step process. First, the Balance Ratio Abs parameter values for
red, green, and blue are each set to 1.5. Then, assuming a "gray world" model, the Balance Ratio
Abs parameter values are automatically adjusted such that the average values for the "red" and
"blue" pixels match the average value for the "green" pixels.
The balance white auto function uses Auto Function AOI 2 and can only be operated in the "once"
mode of operation.
If Auto Function AOI 2 does not overlap the Image AOI (see the "Auto Function AOI" section) the
pixel data from Auto Function AOI 2 will not be used to control the white balance of the image.
However, as soon as the Balance White Auto function is set to "once" operation mode, the Balance
Ratio Abs parameter values for red, green, and blue are each set to 1.5. These settings will control
the white balance of the image.
For more information about setting the white balance "manually", see Section 8.4 on
Setting the balance white auto functionality using Basler pylon is a several step process:
Select the Auto Function AOI 2.
Set the value of the Offset X, Offset Y, Width, and Height parameters for the AOI.
Set the value of the Exposure Auto parameter for the "once" or the "continuous" mode of
operation.
You can set the white balance auto functionality from within your application software by using the
pylon API. The following code snippets illustrate using the API to set the balance auto functionality:
// Select auto function AOI 2
Camera.AutoFunctionAOISelector.SetValue( AutoFunctionAOISelector_AOI2 );
// Set the position and size of selected auto function AOI. In this example, we set
// auto function AOI to cover the entire sensor.
Camera.AutoFunctionAOIOffsetX.SetValue( 0 );
Camera.AutoFunctionAOIOffsetY.SetValue( 0 );
Camera.AutoFunctionAOIWidth.SetValue( Camera.AutoFunctionAOIWidth.GetMax() );
Camera.AutoFunctionAOIHeight.SetValue( Camera.AutoFunctionAOIHeight.GetMax() );
// Set mode of operation for balance white auto function
Camera.BalanceWhiteAuto.SetValue( BalanceWhiteAuto_Once );
You can also use the Basler pylon Viewer application to easily set the parameters.
For more information about the pylon API and the pylon Viewer, see Section 3 on
For general information about auto functions, see Section 10.9 on
For information about Auto Function AOIs and how to set them, see Section 10.9.1.2 on
Basler ace GigE
Standard Features
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