GreyInertiaOrientationChiSee full documentation

Measure allowing to compute the shape 3d orientation (chi component) from the second order moment matrix computed from the GreyInertia measurement for shape.

This measure computes the orientation value of the inertia matrix calculated for each shape, taking the pixels intensities into account, and returns the chi component, expressed in radians.

Here is an example of chi component of the orientation values 3d measurement. The intensity used to compute the measures are 1 if the pixel is inside a shape and 0 otherwise. Consequently, we get the same results than Inertia3dOrientationChi :

Measure allowing to compute the chi component of the 3d orientation from the second order moment matrix computed from the GreyInertia measurement for shape

Measure synthesis :

Measure Type	Measure Unit Type	Parameter Type	Result Type	Shape Requirements
Generic	Angle	None	Value (ipsdk::ipReal64)	Row Intersections

See Shape measurement for additional information on these pictograms

Example of Python code :

Generic example in 3d case :

import PyIPSDK
import PyIPSDK.IPSDKIPLShapeAnalysis as shapeanalysis

    # Create the infoset
    inMeasureInfoSet3d = PyIPSDK.createMeasureInfoSet3d()
    PyIPSDK.createMeasureInfo(inMeasureInfoSet3d, "GreyInertiaOrientationChiMsr")
    
    #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("GreyInertiaOrientationChiMsr")
    
    # 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 pInGreyImg3d = loadTiffImageFile(inputGreyImgPath, eTiffDirectoryMode::eTDM_Volume);

    // read entity shape 2d collection used for processing
    Shape3dCollPtr pShape3dColl = boost::make_shared<Shape3dColl>();
    readFromBinaryFile(inputShape3dCollPath, *pShape3dColl);

    // define a measure info set
    MeasureInfoSetPtr pMeasureInfoSet = MeasureInfoSet::create3dInstance();
    createMeasureInfo(pMeasureInfoSet, "GreyInertiaOrientationChiMsr");
    
    // compute measure on shape 3d collection
    MeasureSetPtr pOutMeasureSet = shapeAnalysis3d(pInGreyImg3d, pShape3dColl, pMeasureInfoSet);

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