ImageRatio

Measure allowing to compute the ratio between the shapes areas and the image area. More...

Classes
class	ipsdk::imaproc::shape::analysis::ImageRatioMsr
	Measurement object for measure ImageRatio. More...
class	ipsdk::imaproc::shape::analysis::ImageRatioMsrInfo
	Information object for measure ImageRatio. More...

Detailed Description

Measure allowing to compute the ratio between the shapes areas and the image area.

This measure computes the ratio between the shapes areas and the image area, in terms of number of pixels. For a given shape, the 2d ratio is calculated as follows :

Where , is the number of pixels of the shape calculated with NbPixels2d and is the number of pixels of the image.

In the 3d case, the ratio is given by :

Where is the number of voxels of the shape calculated with NbPixels3d and is the volume of the image.

Here is an example of image ratio measurement in 2d case :

Author

R. Abbal

Date

2015/07/16

Copyright

2015 Reactiv'IP, all right reserved.

Measure allowing to compute the ratio between the shapes areas and the image area

Measure synthesis :

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

Measure Unit Type:

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

Measure Parameter Type :

Measure ImageRatio has no parameters

Measure Result Type :

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

Measure Shape Requirements :

Measure ImageRatio requires row intersections from shape data

Measure Dependencies :

Measure ImageRatio depends on following measures :

Measure Mode	Measure Name	Measure Type	Measure Parameters
eMVP_2d	Volume	NbPixels2d
eMVP_3d	Volume	NbPixels3d

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, "ImageRatioMsr")
    
    #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("ImageRatioMsr")
    
    # retrieve measure values
    outMsrValues = outMsr.getMeasureResult().getColl(0)
    print("First label measurement equal " + str(outMsrValues[1]))

Generic example in 3d case :

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

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