Circularity2d

Compute the circularity of a shape. More...

Classes
class	ipsdk::imaproc::shape::analysis::Circularity2dMsr
	Measurement object for measure Circularity2d. More...
class	ipsdk::imaproc::shape::analysis::Circularity2dMsrInfo
	Information object for measure Circularity2d. More...

Typedefs
typedef HolesBasicPolicyMsrParams	ipsdk::imaproc::shape::analysis::Circularity2dMsrParams
	parameter type associated to class

Detailed Description

Compute the circularity of a shape.

Circularity2d measure is adapted of the sphericity formula for 2d case.

It computes circularity of a 2d shape as follows :

Where is the shape area, calculated with Area2d, and is the shape perimeter.

Here is an example of circularity measurement :

Note

The 2d circularity is the 2d equivalent of the Sphericity3d measure.

See also

https://en.wikipedia.org/wiki/Sphericity

Author

R. Abbal

Date

2015/07/17

Copyright

2015 Reactiv'IP, all right reserved.

Compute the circularity of a shape

Measure synthesis :

Measure Type	Measure Unit Type	Parameter Type	Result Type	Shape Requirements
Generic	None	Circularity2dMsrParams	Value (ipsdk::ipReal64)	Boundary Approximation

See Shape measurement for additional information on these pictograms

Measure Type :

This is a generic measure

• it does not directly use shape or image data
• it can use dependencies to other measures to compute a result (see Measure Dependencies section)

This measure can only be used in 2d case

Measure Unit Type:

Measure Circularity2d is not associated to any unit [ipsdk::shape::analysis::eMsrUnitFormat::eMUF_NoUnit]

Measure Parameter Type :

Measure Circularity2d is associated to Circularity2dMsrParams parameters

Measure Result Type :

Measure Circularity2d is associated to ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64> results

Measure Shape Requirements :

Measure Circularity2d requires boundary approximation from shape data

Measure Dependencies :

Measure Circularity2d depends on following measures :

Measure Mode	Measure Name	Measure Type	Measure Parameters
eMVP_2d	Area2d	PolygonArea2d	createHolesBasicPolicyMsrParams(_pMsrParams->getValue<Circularity2dMsrParams::ProcessHoles>())
eMVP_2d	Perimeter2d	Perimeter2d	createHolesBasicPolicyMsrParams(_pMsrParams->getValue<Circularity2dMsrParams::ProcessHoles>())

Note

See Shape Analysis 2d for more information on general shape 2d analysis and measurement usage.

Example of Python code :

Generic example in 2d case :

import PyIPSDK
import PyIPSDK.IPSDKIPLShapeAnalysis as shapeanalysis

    # Create the infoset
    inMeasureInfoSet2d = PyIPSDK.createMeasureInfoSet2d()
    PyIPSDK.createMeasureInfo(inMeasureInfoSet2d, "Circularity2dMsr")
    
    #Perform the analysis
    outMeasureSet = shapeanalysis.labelAnalysis2d(inGreyImg, inLabelImg2d, inMeasureInfoSet2d)
    
    # save results to csv format
    PyIPSDK.saveCsvMeasureFile(os.path.join(tmpPath,  "shape_analysis_results.csv"), outMeasureSet)
    
    # retrieve measure results
    outMsr = outMeasureSet.getMeasure("Circularity2dMsr")
    
    # retrieve measure values
    outMsrValues = outMsr.getMeasureResult().getColl(0)
    print("First label measurement equal " + str(outMsrValues[1]))

Example of C++ code :

Example informations

Associated library

IPSDKIPLShapeAnalysis

Code Example

    // opening grey level input image
    ImagePtr pInGreyImg2d = loadTiffImageFile(inputGreyImgPath);

    // read entity shape 2d collection used for processing
    Shape2dCollPtr pShape2dColl = boost::make_shared<Shape2dColl>();
    readFromXmlFile(inputShape2dCollPath, *pShape2dColl);

    // define a measure info set
    MeasureInfoSetPtr pMeasureInfoSet = MeasureInfoSet::create2dInstance();
    createMeasureInfo(pMeasureInfoSet, "Circularity2dMsr", createHolesBasicPolicyMsrParams(bProcessHoles));
    
    // compute measure on shape 2d collection
    MeasureSetPtr pOutMeasureSet = shapeAnalysis2d(pInGreyImg2d, pShape2dColl, pMeasureInfoSet);

    // retrieve associated results
    const MeasureConstPtr& pCircularity2dOutMsr = pOutMeasureSet->getMeasure("Circularity2dMsr");
    const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>& outResults = static_cast<const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>&>(pCircularity2dOutMsr->getMeasureResult());