AspectRatio

Measure the aspect ratio of a shape (measure based on polygonal or polyhedral approximation) More...

Classes
class	ipsdk::imaproc::shape::analysis::AspectRatioMsr
	Measurement object for measure AspectRatio. More...
class	ipsdk::imaproc::shape::analysis::AspectRatioMsrInfo
	Information object for measure AspectRatio. More...
class	ipsdk::imaproc::shape::analysis::AspectRatioMsrParams
	Parameter object for measure AspectRatio. More...

Functions
IPSDKIPLSHAPEANALYSIS_API AspectRatioMsrParamsPtr	ipsdk::imaproc::shape::analysis::createAspectRatioMsrParams (ipsdk::ipUInt32 nbOrientations=36)
	function allowing to create a new parameter object for AspectRatio measure

Detailed Description

Measure the aspect ratio of a shape (measure based on polygonal or polyhedral approximation)

AspectRatio measure computes the aspect ratio of a shape, that equals to the minimal Feret diameter divided by the maximal Feret diameter of the shape (see MinFeretDiameter and MaxFeretDiameter)

Here is an example of aspect ratio measurement with an orientation step of 1° on a 2d shape:

Author

H. Delestre

Date

2015/07/17

Copyright

2015 Reactiv'IP, all right reserved.

Measure the aspect ratio of a shape

Measure synthesis :

Measure Type	Measure Unit Type	Parameter Type	Result Type	Shape Requirements
Generic	None	AspectRatioMsrParams	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 be used in 2d and 3d case

Measure Unit Type:

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

Measure Parameter Type :

Measure AspectRatio is associated to AspectRatioMsrParams parameters

Measure Result Type :

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

Measure Shape Requirements :

Measure AspectRatio requires boundary approximation from shape data

Measure Dependencies :

Measure AspectRatio depends on following measures :

Measure Mode	Measure Name	Measure Type	Measure Parameters
eMVP_2d3d	MinFeretDiameter	MinFeretDiameter	createMinFeretDiameterMsrParams(_pMsrParams->getValue<AspectRatioMsrParams::NbOrientations>())
eMVP_2d3d	MaxFeretDiameter	MaxFeretDiameter	createMaxFeretDiameterMsrParams(_pMsrParams->getValue<AspectRatioMsrParams::NbOrientations>())

Note

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

See Shape Analysis 3d for more information on general shape 3d 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, "AspectRatioMsr")
    
    #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("AspectRatioMsr")
    
    # retrieve measure values
    outMsrValues = outMsr.getMeasureResult().getColl(0)
    print("First label measurement equal " + str(outMsrValues[1]))

Generic example in 3d case :

import PyIPSDK
import PyIPSDK.IPSDKIPLShapeAnalysis as shapeanalysis

    # Create the infoset
    inMeasureInfoSet3d = PyIPSDK.createMeasureInfoSet3d()
    PyIPSDK.createMeasureInfo(inMeasureInfoSet3d, "AspectRatioMsr")
    
    #Perform the analysis
    outMeasureSet = shapeanalysis.labelAnalysis3d(inGreyImg, inLabelImg, inMeasureInfoSet3d)
    
    # save results to csv format
    PyIPSDK.saveCsvMeasureFile(os.path.join(tmpPath,  "shape_analysis_results.csv"), outMeasureSet)
    
    # retrieve measure results
    outMsr = outMeasureSet.getMeasure("AspectRatioMsr")
    
    # 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, "AspectRatioMsr", createAspectRatioMsrParams(180));
    
    // compute measure on shape 2d collection
    MeasureSetPtr pOutMeasureSet = shapeAnalysis2d(pInGreyImg2d, pShape2dColl, pMeasureInfoSet);

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