Gain#

相机的 Gain 功能可让您增加相机输出图像的亮度。

Increasing the gain increases all pixel values of the images.

要自动调整增益值，请使用 Gain Auto 功能。

该功能的使用#

模拟和数字增益#

The gain is an amplification factor applied to all pixel values of the acquired images. There are different types of gains:

• Analog gain is applied before the signal from the camera sensor is converted into digital values.
• Digital gain is applied after the conversion, i.e., it is basically a multiplication of the digitized values.

Depending on your camera model, the mechanisms to control the gain can vary:

• 对于部分相机，增益控制为模拟式，并且达到一定阈值。高于阈值时，增益控制为数字式。
• For some cameras, gain control is entirely digital or analog.
• For some cameras, you can use the GainSelector parameter to manually switch between analog and digital gain.

Choosing the Gain Type#

On some camera models, the GainSelector parameter is available. This parameter allows you to apply a universal gain, which can be analog, digital, or both, depending on your camera model and the sensor used. The GainSelector parameter also allows you to manually switch between analog and digital gain (if available).

在 racer 2 L cameras, the GainSelector parameter can be used to apply the gain to a specific sensor line if the camera is operated in Dual Line sensor acquisition mode.

You can set the GainSelector parameter to one of the following values, if available:

• All: A universal gain is applied.
• AnalogAll: An analog gain is applied.
• DigitalAll: A digital gain is applied.
• Line1: A digital gain is applied to line 1.
• Line2: A digital gain is applied to line 2.

Conversion Gain Mode#

On a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras, the BslConversionGainMode parameter is available. It allows you to select one of the following conversion gain modes:

• High: Enables the High Conversion Gain (HCG) mode.
  HCG helps to improve image quality in low light conditions. The sensitivity is increased and the readout noise reduced, which results in an improved signal-to-noise ratio, but a lower dynamic range.
• Low: Enables the Low Conversion Gain (LCG) mode.
  LCG is recommended for normal to bright light conditions. The saturation capacity is increased and the dynamic range is higher.

“原始”和绝对增益值#

在部分相机机型上，必须以整数比例将增益输入为“原始”值。相机需要其内部处理机制的原始值。但是，原始值与实际增益值不同，实际增益值以分贝 (dB) 表示。

在特定于相机的 Gain Properties 表中，您可以找到一个公式，可以根据原始增益值计算绝对增益（以 dB 为单位）。

附加参数#

On boA13440-17cm cameras, the BslGainTopLeft, BslGainTopRight, BslGainBottomLeft, and BslGainBottomRight parameters are available. You can use these parameters to increase the brightness individually in each of the four quadrants of the image. This can be useful to compensate for differences in the image brightness.

The brightness in each quadrant can be increased linearly by up to 5 % (digital gain).

Setting the Gain#

1. 设置 GainAuto parameter to Off.
2. 如果可用，请设置 GainSelector parameter to the desired gain type, e.g., All.
3. 如果可用，请设置 BslConversionGain parameter to the desired conversion gain mode, e.g., High.
4. 设置 Gain parameter to the desired value.
   The minimum and maximum parameter values vary depending on the camera model, the pixel format chosen, and the Binning settings.

详情#

增益属性#

显示所有相机型号

增益值#

显示所有相机型号

示例代码#

ace Classic/U/L GigE 相机#

// Set the "raw" gain value to 400
// If you want to know the resulting gain in dB, use the formula given in this topic
camera.GainRaw.SetValue(400);

INodeMap& nodemap = camera.GetNodeMap();
// Set the "raw" gain value to 400
// If you want to know the resulting gain in dB, use the formula given in this topic
CIntegerParameter(nodemap, "GainRaw").SetValue(400);

// Set the "raw" gain value to 400
// If you want to know the resulting gain in dB, use the formula given in this topic
camera.Parameters[PLCamera.GainRaw].SetValue(400);

/* 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 */
/* Set the "raw" gain value to 400 */
/* If you want to know the resulting gain in dB, use the formula given in this topic */
errRes = PylonDeviceSetIntegerFeature(hdev, "GainRaw", 400);
CHECK(errRes);

# Set the "raw" gain value to 400
# If you want to know the resulting gain in dB, use the formula given in this topic
camera.GainRaw.Value = 400

其他相机#

// Select the type of gain
camera.GainSelector.SetValue(GainSelector_All);
// Set the conversion gain mode to High
// Note: Available on a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras only
camera.BslConversionGainMode.SetValue(BslConversionGainMode_High);
// Set the gain to 4.2 dB
camera.Gain.SetValue(4.2);
// Increase the gain in the top-left quadrant of the image by 3 %
// Note: Available on boA13440-17cm cameras only
camera.BslGainTopLeft.SetValue(1.03);

INodeMap& nodemap = camera.GetNodeMap();
// Select the type of gain
CEnumParameter(nodemap, "GainSelector").SetValue("All");
// Set the conversion gain mode to High
// Note: Available on a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras only
CEnumParameter(nodemap, "BslConversionGainMode").SetValue("High");
// Set the gain to 4.2 dB
CFloatParameter(nodemap, "Gain").SetValue(4.2);
// Increase the gain in the top-left quadrant of the image by 3 %
// Note: Available on boA13440-17cm cameras only
CFloatParameter(nodemap, "BslGainTopLeft").SetValue(1.03);

// Select the type of gain
camera.Parameters[PLCamera.GainSelector].SetValue(PLCamera.GainSelector.All);
// Set the conversion gain mode to High
// Note: Available on a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras only
camera.Parameters[PLCamera.BslConversionGainMode].SetValue(PLCamera.BslConversionGainMode.High);
// Set the gain to 4.2 dB
camera.Parameters[PLCamera.Gain].SetValue(4.2);
// Increase the gain in the top-left quadrant of the image by 3 %
// Note: Available on boA13440-17cm cameras only
camera.Parameters[PLCamera.BslGainTopLeft].SetValue(1.03);

/* 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 the type of gain */
errRes = PylonDeviceFeatureFromString(hdev, "GainSelector", "All");
CHECK(errRes);
/* Set the conversion gain mode to High */
/* Note: Available on a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras only */
errRes = PylonDeviceFeatureFromString(hdev, "BslConversionGainMode", "High");
CHECK(errRes);
/* Set the gain to 4.2 dB */
errRes = PylonDeviceSetFloatFeature(hdev, "Gain", 4.2);
CHECK(errRes);
/* Increase the gain in the top-left quadrant of the image by 3 % */
/* Note: Available on boA13440-17cm cameras only */
errRes = PylonDeviceSetFloatFeature(hdev, "BslGainTopLeft", 1.03);
CHECK(errRes);

# Select the type of gain
camera.GainSelector.Value = "All"
# Set the conversion gain mode to High
# Note: Available on a2A2048-35gmSWIR, a2A2048-110umSWIR, a2A2560-20gmSWIR, and a2A2560-70umSWIR cameras only
camera.BslConversionGainMode.Value = "High"
# Set the gain to 4.2 dB
camera.Gain.Value = 4.2
# Increase the gain in the top-left quadrant of the image by 3 %
# Note: Available on boA13440-17cm cameras only
camera.BslGainTopLeft.Value = 1.03

您也可以使用 pylon Viewer 轻松设置参数。