Inertia Orientation 2d

Measure allowing to compute the shape orientation from the second order moment matrix computed from the Inertia2d measurement for 2d shape. More...

Classes
class	ipsdk::imaproc::shape::analysis::InertiaOrientation2dMsr
	Measurement object for measure InertiaOrientation2d. More...
class	ipsdk::imaproc::shape::analysis::InertiaOrientation2dMsrInfo
	Information object for measure InertiaOrientation2d. More...

Detailed Description

Measure allowing to compute the shape orientation from the second order moment matrix computed from the Inertia2d measurement for 2d shape.

This measure computes the orientation value of the inertia matrix calculated for each shape, without taking the pixels intensities into account.

Here is an example of orientation 2d measurement :

See Inertia2d for more details about the inertia calculation.

Author

R. Abbal

Date

2015/07/30

Copyright

2015 Reactiv'IP, all right reserved.

Measure allowing to compute the shape orientation from the second order moment matrix computed from the Inertia2d measurement for 2d 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

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 InertiaOrientation2d is associated to an angular (radians) measurement unit [ipsdk::shape::analysis::eMsrUnitFormat::eMUF_RadianUnit]

Measure Parameter Type :

Measure InertiaOrientation2d has no parameters

Measure Result Type :

Measure InertiaOrientation2d is associated to ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64> results

Measure Shape Requirements :

Measure InertiaOrientation2d requires row intersections from shape data

Measure Dependencies :

Measure InertiaOrientation2d depends on following measures :

Measure Mode	Measure Name	Measure Type	Measure Parameters
eMVP_2d	Inertia	Inertia2d

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, "InertiaOrientation2dMsr")
    
    #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("InertiaOrientation2dMsr")
    
    # 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, "InertiaOrientation2dMsr");
    
    // compute measure on shape 2d collection
    MeasureSetPtr pOutMeasureSet = shapeAnalysis2d(pInGreyImg2d, pShape2dColl, pMeasureInfoSet);

    // retrieve associated results
    const MeasureConstPtr& pInertiaOrientation2dOutMsr = pOutMeasureSet->getMeasure("InertiaOrientation2dMsr");
    const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>& outResults = static_cast<const ipsdk::shape::analysis::ValueMeasureResult<ipsdk::ipReal64>&>(pInertiaOrientation2dOutMsr->getMeasureResult());