Circle Fitting

This code snippet shows how to create a circle measurement tool, adjust the transition parameters, set the nominal gauge position, perform the measurement and retrieve the result.

C++

#include <eVision/EasyGauge/ECircleGauge.h>

using namespace eVision;
// Image constructor
EImageBW8 srcImage;
// ECircleGauge constructor
ECircleGauge circleGauge;
// Adjust the transition parameters
circleGauge.SetTransitionType(ETransitionType_Bw);
circleGauge.SetTransitionChoice(ETransitionChoice_LargestAmplitude);
// Set the Circle fitting gauge position, diameter (50 units),
// starting angle (10), and amplitude (270)
EPoint center(256.f, 256.f);
ECircle circle(center, 50.f, 10.f, 270.f);
circleGauge.SetCircle(circle);
try
{
  // Measure
  ECircle measured = circleGauge.Measure(srcImage);
  // Get the center point coordinates and the radius of the fitted circle
  float centerX = measured.GetCenter().GetX();
  float centerY = measured.GetCenter().GetY();
  float radius = measured.GetRadius();
}
catch (const EException& e)
{
  // The circle was not found.
}

// Save the circle gauge measurement context
circleGauge.Save("myCircleGauge.gge");

C#

using eVision;

// Image constructor
EImageBW8 srcImage = new EImageBW8();
// ECircleGauge constructor
ECircleGauge circleGauge = new ECircleGauge();
// Adjust the transition parameters
circleGauge.TransitionType = ETransitionType.Bw;
circleGauge.TransitionChoice = ETransitionChoice.LargestAmplitude;
// Set the Circle fitting gauge position, diameter (50 units),
// starting angle (10°), and amplitude (270°)
EPoint center = new EPoint(256.0f, 256.0f);
ECircle circle = new ECircle(center, 50.0f, 10.0f, 270.0f);
circleGauge.Circle = circle;
// Measure
try
{
  ECircle measured = circleGauge.Measure(srcImage);
  // Get the center point coordinates and the radius of the fitted circle
  float centerX = measured.Center.X;
  float centerY = measured.Center.Y;
  float radius = measured.Radius;
}
catch (EException e)
{
  // The circle was not found.
}

// Save the circle gauge measurement context
circleGauge.Save("myCircleGauge.gge");

Python

import eVision
# Image constructor
src_image = eVision.EImageBW8()
# ECircleGauge constructor
circle_gauge = eVision.ECircleGauge()
# Adjust the transition parameters
circle_gauge.TransitionType = eVision.ETransitionType.Bw
circle_gauge.TransitionChoice = eVision.ETransitionChoice.LargestAmplitude
# Set the Circle fitting gauge position, diameter (50 units),
# starting angle (10°), and amplitude (270°)
center = eVision.EPoint(256.0, 256.0)
circle = eVision.ECircle(center, 50.0, 10.0, 270.0)
circle_gauge.Circle = circle
try:
    # Measure
    measured = circle_gauge.Measure(src_image)
    # Get the center point coordinates and the radius of the fitted circle
    centerX = measured.Center.X
    centerY = measured.Center.Y
    radius = measured.Radius
except eVision.EException:
    # The circle was not found.
    pass

# Save the circle gauge measurement context
circle_gauge.Save("myCircleGauge.gge")