ReferenceColorSimilarity (TcVnVector3_LREAL)

Computes the similarity to a reference color for each pixel in the source image.
Can use available TwinCAT Job Tasks for executing parallel code regions.
Can return partial results when canceled by Watchdog.

Syntax

Definition:

HRESULT ReferenceColorSimilarity(
    HRESULT            hrPrev,
    ITcVnImage*        ipSrcImage,
    ITcVnImage*&       ipDestImage,
    TcVnVector3_LREAL& aRefColor,
    float              fVariance = 0.15f,
    float              fLuminanceWeight = 0
)

Parameters

Name	Type	Default	Description
hrPrev	HRESULT		HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)
ipSrcImage	ITcVnImage*		RGB source image (USINT, 3 channels)
ipDestImage	ITcVnImage*&		Returns the similarity to aRefColor for each pixel in ipSrcImage (USINT, 1 channel. An appropriate destination image will be created if required.)
aRefColor	TcVnVector3_LREAL&		Reference color (RGB, [0..255])
fVariance	float	0.15f	Allowed color variance (0.1 - 0.3 might be a good start to try)
fLuminanceWeight	float	0	Weight the impact of the luminance ([0..1], e.g. set to 0 to be more resistant to unequal illumination, but might be required to differentiate between some colors)

Return value

HRESULT

Required License

TC3 Vision Base

System Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT V3.1. 4024.44 or later	PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU	Tc3_Vision