Skeleton2dMeanEdgeLength

Mean edge length for graph associated to skeleton 2d. More...

Classes
class	ipsdk::imaproc::shape::analysis::Skeleton2dMeanEdgeLengthMsr
	Measurement object for measure Skeleton2dMeanEdgeLength. More...
class	ipsdk::imaproc::shape::analysis::Skeleton2dMeanEdgeLengthMsrInfo
	Information object for measure Skeleton2dMeanEdgeLength. More...
class	ipsdk::imaproc::shape::analysis::Skeleton2dMeanEdgeLengthMsrParams
	Parameter object for measure Skeleton2dMeanEdgeLength. More...

Detailed Description

Mean edge length for graph associated to skeleton 2d.

Skeleton 2d mean edge length measure is based on skeleton 2d measure (see [Concept] Skeleton 2d). This measure allows to compute mean length of edges composing a shape 2d skeleton.

Searched edge type can be customized (setting measure parameter ipsdk::geom::eSkeletonEdgeCategory) :

• eSEC_All to process all edges
• eSEC_Leaf to process only leaf edges which are edges connected to a polygon point (red edges for main skeleton and black edges for hole skeleton)
• eSEC_Branch to process only branch edges which are edges not connected to polygon point (green edges for main skeleton and blue edges for hole skeleton)

Note

Note that measure results depend on skeleton 2d holes processing policy See [Concept] Skeleton 2d for more informations on usage of ipsdk::shape::segmentation::eSkeleton2dHolesPolicy enumerate value. If holes processing policy is set to eSHP_ExtractedAndAnalyzed, holes skeleton edge length are taken into account with respect to associated edge length for global mean edge length computation.

Here is an example of measure results for different skeleton 2d holes processing policy and different searched edge types.

Author

E.Noirfalise

Date

2016/08/24

Copyright

2016 Reactiv'IP, all right reserved.

Mean edge length for graph associated to skeleton 2d

Measure synthesis :

Measure Type	Measure Unit Type	Parameter Type	Result Type	Shape Requirements
Generic	Length	Skeleton2dMeanEdgeLengthMsrParams	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 Skeleton2dMeanEdgeLength is associated to a length measurement unit [ipsdk::shape::analysis::eMsrUnitFormat::eMUF_LengthUnit]

Measure Parameter Type :

Measure Skeleton2dMeanEdgeLength is associated to Skeleton2dMeanEdgeLengthMsrParams parameters

Measure Result Type :

Measure Skeleton2dMeanEdgeLength is associated to ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64> results

Measure Shape Requirements :

Measure Skeleton2dMeanEdgeLength requires boundary approximation from shape data

Measure Dependencies :

Measure Skeleton2dMeanEdgeLength depends on following measures :

Measure Mode	Measure Name	Measure Type	Measure Parameters
eMVP_2d	Skeleton	Skeleton2d	createSkeleton2dMsrParams(_pMsrParams->getValue<Skeleton2dMeanEdgeLengthMsrParams::HolesPolicy>())

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.createGeometricCalibration2d(1,1,'px'))
    PyIPSDK.createMeasureInfo(inMeasureInfoSet2d, "Skeleton2dMeanEdgeLengthMsr", shapeanalysis.createSkeleton2dMeanEdgeLengthMsrParams(PyIPSDK.eSHP_Ignored, PyIPSDK.eSEC_Leaf))
    
    #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("Skeleton2dMeanEdgeLengthMsr")
    
    # 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>();
    IPSDK_REQUIRE(readFromXmlFile(inputShape2dCollPath, *pShape2dColl) == true);

    // define a measure info set
    MeasureInfoSetPtr pMeasureInfoSet = MeasureInfoSet::create2dInstance();
    createMeasureInfo(pMeasureInfoSet, "Skeleton2dMeanEdgeLengthMsr", createSkeleton2dMeanEdgeLengthMsrParams(skeleton2dHolesPolicy, skeletonEdgeCategory));
    
    // compute measure on shape 2d collection
    MeasureSetPtr pOutMeasureSet = shapeAnalysis2d(pInGreyImg2d, pShape2dColl, pMeasureInfoSet);

    // retrieve associated results
    const MeasureConstPtr& pSkeleton2dMeanEdgeLengthOutMsr = pOutMeasureSet->getMeasure("Skeleton2dMeanEdgeLengthMsr");
    const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>& outResults = static_cast<const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>&>(pSkeleton2dMeanEdgeLengthOutMsr->getMeasureResult());