IMcProfileEdgesExBackgroundAvgLength Property

Property Value

Type: Int32

The effect of the BackgroundAvgLength property is dependent on the EdgeFindingMethod. For the mcpefmRisingEdges and mcpefmFallingEdges methods, the property is ignored and has no effect: these methods are inherently background-independent since they work on the 1st derivative of the luminance profile. For the other methods, the property is ignored unless it is greater than the MatchLength property. For the mcpefmPeaks and mcpefmValleys methods, if the BackgroundAvgLength is greater than the MatchLength, then a simple background average of this length (equally weighted) is subtracted from the profile luminance. The effect is to make peak/valley detection local to a length on the order of the BackgroundAvgLength. For the mcpefmMatchPattern EdgeFindingMethod, the action of a BackgroundAvgLength larger than the MatchLength is to effectively high-pass the background with a filter length of BackgroundAvgLength as part of correlating the luminance profile with the Pattern property. The effect here is to make the method less local, while without BackgroundAvgLength the pattern is correlated only along the MatchLength.