ReadDotCodeRoi

Detect and interpret a DotCode within the provided image. The code should be in the image center and horizontally or vertically aligned.
Can use available TwinCAT Job Tasks for executing parallel code regions.

Syntax

Definition:

HRESULT ReadDotCodeRoi(
    HRESULT          hrPrev,
    ITcVnImage*      ipSrcImage,
    ITcVnContainer*& ipDecodedData,
    float            fModuleWidth,
    float&           fAngleDeg,
    ITcVnContainer** pipContour = nullptr,
    ULONGLONG        eOptions = DCO_DEFAULT
)

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 elements, 1 channel)

ipDecodedData

ITcVnContainer*&

 

Returns the decoded code (ContainerType_String_SINT)

fModuleWidth

float

 

Average dot diameter of the code in the image (in pixels). Must be at least 3, preferably 5 - 8.

fAngleDeg

float&

 

Returns the clockwise rotation angle in degree

pipContour

ITcVnContainer**

nullptr

Returns the contour of the detected code (ContainerType_Vector_TcVnPoint2_DINT; optional, set to 0 if not required)

eOptions

ULONGLONG

DCO_DEFAULT

Specifies a combination of one or more ETcVnDotCodeOptions

 Return value

HRESULT

Further information

The F_VN_ReadDotCodeRoi function searches for a single DotCode within a defined region of interest (ROI) and decodes it. This requires that the code be centered within the provided image.

fModuleWidth

The fModuleWidth parameter defines the expected average diameter of the individual DotCode modules (dots) in pixels. The module size must be at least 3 pixels, whereby 5 to 8 pixels are recommended for optimum and reliable results. Significant deviations from the parameterized value can lead to increased processing time or no result.

Rotation angle (Return value)

The return value fAngleDeg returns the clockwise rotation angle.

Required License

TC3 Vision Code Reading