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Balance White Auto#

相机的 Balance White Auto 功能会自动校正所采集到的图像中的色彩偏移。

自动功能的像素数据可以来自一个或多个自动功能 ROI

要手动纠正色彩偏移,请使用 Balance White 功能。

该功能的使用#

启用或禁用 Balance White Auto#

要启用或禁用 Balance White Auto 自动功能:

  1. 至少一个自动功能 ROI 分配给 Balance White Auto 自动功能。
    确保自动功能 ROI 部分或完全与图像 ROI 重叠。
  2. 设置 BalanceWhiteAuto 参数设置为以下工作模式之一:
    • Once: The camera adjusts the white balance until the average gray values for red, green, and blue are identical. When this has been achieved, or after several calculation cycles, the camera sets the auto function to Off and applies the balance ratios resulting from the last calculation to all following images.
    • Continuous: The camera adjusts the white balance continuously while images are being acquired. The adjustment process continues until the operating mode is set to Once or Off.
    • Off: Disables the Balance White Auto auto function. The BalanceRatio parameters remain at the values resulting from the last automatic or manual adjustment.

信息

On the following camera models, the Continuous operating mode is not available: acA1600-20gc, acA1920-25gc, acA2500-14gc.

运作原理#

自动白平衡分为两个步骤:

  1. The camera compares the average gray values of the red, green, and blue pixels. It determines the color with the highest average gray value (i.e., the brightest color) and sets the BalanceRatio parameter value for this color to 1.
  2. The camera automatically adjusts the BalanceRatio parameter values of the other two colors until the average gray values for red, green, and blue are identical.

As a result, the BalanceRatio parameter is set to 1 for one color and to a value between 1 and ≈15.98 for the other two colors.

Example: Assume the green pixels in your image have the highest average gray value. If you enable the Balance White Auto auto function, the camera sets the BalanceRatio parameter value for green to 1. Then, the camera automatically adjusts the BalanceRatio parameter values for red and blue until the average gray values for red, green, and blue are identical. The new balance ratios could be, e.g., green = 1, red = 1.08789, and blue = 2.19678.

信息

  • To view the BalanceRatio parameter values for red, green, or blue, switch to the respective color channel using the BalanceRatioSelector.
  • 当相机连续拍摄图像时,自动功能会在经过较短的延迟后生效。前几张图像可能不受自动功能的影响。

示例代码#

ace Classic/U/L GigE 相机#
// Select auto function ROI 2
camera.AutoFunctionAOISelector.SetValue(AutoFunctionAOISelector_AOI2);
// Enable the Balance White Auto auto function
// for the auto function ROI selected
camera.AutoFunctionAOIUsageWhiteBalance.SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
camera.BalanceWhiteAuto.SetValue(BalanceWhiteAuto_Continuous);
INodeMap& nodemap = camera.GetNodeMap();
// Select auto function ROI 2
CEnumParameter(nodemap, "AutoFunctionAOISelector").SetValue("AOI2");
// Enable the Balance White Auto auto function
// for the auto function ROI selected
CBooleanParameter(nodemap, "AutoFunctionAOIUsageWhiteBalance").SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
CEnumParameter(nodemap, "BalanceWhiteAuto").SetValue("Continuous");
// Select auto function ROI 2
camera.Parameters[PLCamera.AutoFunctionAOISelector].SetValue(PLCamera.AutoFunctionAOISelector.AOI2);
// Enable the Balance White Auto auto function
// for the auto function ROI selected
camera.Parameters[PLCamera.AutoFunctionAOIUsageWhiteBalance].SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
camera.Parameters[PLCamera.BalanceWhiteAuto].SetValue(PLCamera.BalanceWhiteAuto.Continuous);
/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
/* Select auto function ROI 2 */
errRes = PylonDeviceFeatureFromString(hdev, "AutoFunctionAOISelector", "AOI2");
CHECK(errRes);
/* Enable the Balance White Auto auto function */
/* for the auto function ROI selected */
errRes = PylonDeviceSetBooleanFeature(hdev, "AutoFunctionAOIUsageWhiteBalance", 1);
CHECK(errRes);
/* Enable Balance White Auto by setting the operating mode to Continuous */
errRes = PylonDeviceFeatureFromString(hdev, "BalanceWhiteAuto", "Continuous");
CHECK(errRes);
# Select auto function ROI 2
camera.AutoFunctionAOISelector.Value = "AOI2"
# Enable the Balance White Auto auto function
# for the auto function ROI selected
camera.AutoFunctionAOIUsageWhiteBalance.Value = True
# Enable Balance White Auto by setting the operating mode to Continuous
camera.BalanceWhiteAuto.Value = "Continuous"
其他相机#
// Select auto function ROI 2
camera.AutoFunctionROISelector.SetValue(AutoFunctionROISelector_ROI2);
// Enable the Balance White Auto auto function
// for the auto function ROI selected
camera.AutoFunctionROIUseWhiteBalance.SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
camera.BalanceWhiteAuto.SetValue(BalanceWhiteAuto_Continuous);
INodeMap& nodemap = camera.GetNodeMap();
// Select auto function ROI 2
CEnumParameter(nodemap, "AutoFunctionROISelector").SetValue("ROI2");
// Enable the Balance White Auto auto function
// for the auto function ROI selected
CBooleanParameter(nodemap, "AutoFunctionROIUseWhiteBalance").SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
CEnumParameter(nodemap, "BalanceWhiteAuto").SetValue("Continuous");
// Select auto function ROI 2
camera.Parameters[PLCamera.AutoFunctionROISelector].SetValue(PLCamera.AutoFunctionROISelector.ROI2);
// Enable the Balance White Auto auto function
// for the auto function ROI selected
camera.Parameters[PLCamera.AutoFunctionROIUseWhiteBalance].SetValue(true);
// Enable Balance White Auto by setting the operating mode to Continuous
camera.Parameters[PLCamera.BalanceWhiteAuto].SetValue(PLCamera.BalanceWhiteAuto.Continuous);
/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
/* Select auto function ROI 2 */
errRes = PylonDeviceFeatureFromString(hdev, "AutoFunctionROISelector", "ROI2");
CHECK(errRes);
/* Enable the Balance White Auto auto function */
/* for the auto function ROI selected */
errRes = PylonDeviceSetBooleanFeature(hdev, "AutoFunctionROIUseWhiteBalance", 1);
CHECK(errRes);
/* Enable Balance White Auto by setting the operating mode to Continuous */
errRes = PylonDeviceFeatureFromString(hdev, "BalanceWhiteAuto", "Continuous");
CHECK(errRes);
# Select auto function ROI 2
camera.AutoFunctionROISelector.Value = "ROI2"
# Enable the Balance White Auto auto function
# for the auto function ROI selected
camera.AutoFunctionROIUseWhiteBalance.Value = True
# Enable Balance White Auto by setting the operating mode to Continuous
camera.BalanceWhiteAuto.Value = "Continuous"

您也可以使用 pylon Viewer 轻松设置参数。