F_VN_CreateStructuringElement

Creates a structuring element for the usage with morphological operators and allocate an appropriate data buffer. The initial reference count is set to one if a new image interface is created and kept, otherwise.

Syntax

Definition:

FUNCTION F_VN_CreateStructuringElement : HRESULT
VAR_INPUT
    ipStructuringElement : Reference To  ITcVnImage;
    eShape               : ETcVnStructuringElementShape;
    nWidth               : UDINT;
    nHeight              : UDINT;
    hrPrev               : HRESULT;
END_VAR

Inputs

Name	Type	Description
ipStructuringElement	Reference To ITcVnImage	Returns the created structuring element (Non-zero interface pointers are reused.)
eShape	ETcVnStructuringElementShape	Shape of the structuring element (rectangle, cross, or ellipse)
nWidth	UDINT	Width
nHeight	UDINT	Height
hrPrev	HRESULT	HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)

Return value

HRESULT

Further information

The function creates a structure element that can be used for morphological operations with F_VN_MorphologicalOperator.

Parameter

Structure element

The structure element created, ipStructuringElement, is returned as ITcVnImage by representing the structure element with pixels with the value 1.

Shape

The shape eShape of the structure element is defined by the enum ETcVnStructuringElementShape. The following shapes are available:

TCVN_SES_RECTANGLE	TCVN_SES_CROSS	TCVN_SES_ELLIPSE

	As the pixel values of the structure element are 1, they were scaled up here for a better display.

Size

The size of the structure element is defined by the width nWidth and height nHeight of the image ipStructuringElement to be created.

Application

The creation of a square structure element of the size 9 looks like this, for example:

hr := F_VN_CreateStructuringElement(
    ipStructuringElement    :=  ipElement,
    eShape                  :=  TCVN_SES_RECTANGLE,
    nWidth                  :=  9,
    nHeight                 :=  9,
    hrPrev                  :=  hr
);

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