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)

ReferenceColorSimilarity (TcVnVector3_LREAL) 1: Return value

HRESULT

Required License

TC3 Vision Base

System Requirements

Development environment

Target platform

PLC libraries to include

TwinCAT V3.1.4024.54 or later

PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU

Tc3_Vision