FindContourHierarchy (Exp)

Search for object contours in a binary image and determine their hierarchical relationship.
Can use available TwinCAT Job Tasks for executing parallel code regions.
Can return partial results when canceled by Watchdog.

Syntax

Definition:

HRESULT FindContourHierarchy(
    HRESULT                         hrPrev,
    ITcVnImage*                     ipSrcImage,
    ITcVnContainer*&                ipContours,
    ITcVnContainer*&                ipHierarchy,
    ETcVnContourRetrievalMode       eRetrievalMode,
    ETcVnContourApproximationMethod eApproximationMethod,
    TcVnPoint&                      aOffset
)

Parameters

Name

Type

Description

hrPrev

HRESULT

HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)

ipSrcImage

ITcVnImage*

Source image (1 channel, binary)

ipContours

ITcVnContainer*&

Returns a container which is filled with the found contours (ContainerType_Vector_Vector_TcVnPoint2_DINT; The elements of this container are single contours. Non-zero interface pointers are reused.)

ipHierarchy

ITcVnContainer*&

Returns a container which is filled with information on the found contours' hierarchy (ContainerType_Vector_TcVnVector4_DINT; The elements of this container are four-dimensional vectors containing the 0-based indices of the next [0] and the previous contour [1] at the same level, the first child [2], and the parent [3]. Non-zero interface pointers are reused.)

eRetrievalMode

ETcVnContourRetrievalMode

Specifies which contours are retrieved and how their relationship is encoded

eApproximationMethod

ETcVnContourApproximationMethod

Contour encoding

aOffset

TcVnPoint&

Offset by which every contour point is shifted

FindContourHierarchy (Exp) 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