F_VN_MeasureAngleBetweenEdges
Measure the angle between 2 edges, using an interpolation method.
Can use available TwinCAT Job Tasks for executing parallel code regions.
Can return partial results when canceled by Watchdog.
Syntax
Definition:
FUNCTION F_VN_MeasureAngleBetweenEdges : HRESULT
VAR_INPUT
ipSrcImage : ITcVnImage;
END_VAR
VAR_IN_OUT
fAngle : REAL;
aInnerPoint : TcVnPoint2_REAL;
aOuterPoint1 : TcVnPoint2_REAL;
aOuterPoint2 : TcVnPoint2_REAL;
END_VAR
VAR_INPUT
eEdgeDirection : ETcVnEdgeDirection;
fMinStrength : REAL;
nSearchLines : UDINT;
hrPrev : HRESULT;
END_VAR
Inputs
|
Name |
Type |
Description |
|---|---|---|
|
ipSrcImage |
Source image (1 channel) | |
|
eEdgeDirection |
Specification of the edge direction from aInnerPoint to aOuterPoint1 and aOuterPoint2 to search for | |
|
fMinStrength |
REAL |
Specification of the minimum strength (intensity difference) of the edge to search for |
|
nSearchLines |
UDINT |
Width of the search windows, i.e. the number of search lines (3, 5, 7, ...), centered around the lines specified by aInnerPoint and aOuterPoint1, aOuterPoint2 |
|
hrPrev |
HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.) |
In/Outputs
|
Name |
Type |
Description |
|---|---|---|
|
fAngle |
REAL |
Returns the angle between the detected edges (radians) |
|
aInnerPoint |
Position inside the angle to measure, from which to start the edge search process (in the direction of aOuterPoint1 and aOuterPoint2) | |
|
aOuterPoint1 |
Position where the search process for edge 1 ends | |
|
aOuterPoint2 |
Position where the search process for edge 2 ends |
Return valueWeiterführende Informationen
Die Funktion F_VN_MeasureAngleBetweenEdges lokalisiert zwei lineare Kanten und misst den Winkel zwischen ihnen.
Parameter
Eingangsbild
Das Eingangsbild ipSrcImage muss ein 1-kanaliges Grauwertbild sein.
Winkel (Rückgabewert)
Der Parameter fAngle gibt den Winkel zwischen den lokalisierten Kanten zurück.
Abhängig vom Parameter bAngleInDegrees ist der Winkel fAngle in Radiant (FALSE) oder in Grad (TRUE) angegeben.
Parameter zur Kantenlokalisierung
Die restlichen Parameter sind ausführlich im Kapitel Kantenlokalisierung erklärt.
Expert-Parameter
Die Expert-Variante F_VN_MeasureAngleBetweenEdgesExp enthält zusätzliche Parameter.
Anwendung
Das Vermessen eines Winkels zwischen zwei linearen Kanten sieht z. B. so aus:
hr := F_VN_MeasureAngleBetweenEdgesExp(
ipSrcImage := ipImageIn,
fAngle := fAngle
aInnerPoint := aInnerPoint,
aOuterPoint1 := aOuterPoint1
aOuterPoint2 := aOuterPoint2,
eEdgeDirection := TCVN_ED_LIGHT_TO_DARK,
fMinStrength := fMinStrength,
nSearchLines := nSearchLines,
hrPrev := hr
);
Beispiele
Required License
TC3 Vision Metrology 2D
System Requirements
Development environment | Target platform | PLC libraries to include |
|---|---|---|
TwinCAT V3.1. 4024.44 or later | PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU | Tc3_Vision |