MatchTemplateAndEvaluate

Match a template image with every location in the source image and evaluate the comparison results. Returns a sorted list of possible matches (best match first).
Can use available TwinCAT Job Tasks for executing parallel code regions.
Can return partial results when canceled by Watchdog.

Syntax

Definition:

HRESULT MatchTemplateAndEvaluate(
    HRESULT                  hrPrev,
    ITcVnImage*              ipSrcImage,
    ITcVnImage*              ipTemplateImage,
    ITcVnContainer*&         ipMatches,
    float                    fMatchThreshold,
    ETcVnTemplateMatchMethod eMatchMethod = TMM_CCORR_NORMED,
    ITcVnImage*              ipTemplateMask = nullptr,
    float                    fScaleFactor = 1,
    ETcVnInterpolationType   eInterpolationType = IT_BILINEAR,
    ITcVnContainer**         pipMatchValues = nullptr
)

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*

 

Source image (USINT or REAL, 1 or 3 channels)

ipTemplateImage

ITcVnImage*

 

Template image (same type as ipSrcImage, smaller width and height)

ipMatches

ITcVnContainer*&

 

Returns the matching positions (ContainerType_Vector_TcVnPoint2_DINT, where each element represents the top-left corner of ipTemplateImage) in ipSrcImage, sorted by relevance (best match first)

fMatchThreshold

float

 

Threshold to separate relevant from irrelevant matches (0..1 for NORMED methods, otherwise dependent on template size and content. To find a suitable value, you could evaluate some sample result images of F_VN_MatchTemplateExp.)

eMatchMethod

ETcVnTemplateMatchMethod

TMM_CCORR_NORMED

Specifies the template match method

ipTemplateMask

ITcVnImage*

nullptr

Optional mask for ipTemplateImage (same type and size as ipTemplateImage)

fScaleFactor

float

1

Factor (0..1] to reduce source and template image width and height for better performance (but less accuracy!)

eInterpolationType

ETcVnInterpolationType

IT_BILINEAR

Image resize interpolation type (only used if fScaleFactor != 1, TCVN_IT_BILINEAR recommended for most cases)

pipMatchValues

ITcVnContainer**

nullptr

Optionally returns the matching values (ContainerType_Vector_REAL, same size and sort order as ipMatches. Set to 0 if not required.)

MatchTemplateAndEvaluate 1: Return value

HRESULT

Required License

TC3 Vision Matching

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