ComparisonSee full documentation

CompareResult =	compareImg (inImg1,inImg2)
CompareResult =	compareImg (inImg1,inImg2,tolerance)

Detailed Description

Algorithm allowing to compare two images.

This algorithm allows to compare two images. Images must have same size and buffer type for comparison.

Through the input parameter InOptImgComparisonTolerance::ToleranceType, the user can choose among several tolerance policies:

• eImgComparisonToleranceType::eICTT_NoTolerance: comparison succeeds if and only if the 2 input images are rigorously identical
• eImgComparisonToleranceType::eICTT_Absolute: comparison succeeds if and only if, for each pair of pixels (in1, in2) at the same position in the 2 input images:
• eImgComparisonToleranceType::eICTT_Relative: comparison succeeds if and only if, for each pair of pixels (in1, in2) at the same position in the 2 input images:
• eImgComparisonToleranceType::eICTT_AbsoluteOrRelative: comparison succeeds if and only if, for each pair of pixels (in1, in2) at the same position in the 2 input images, at least one of the 2 following conditions is satisfied:
  1. 
  2. 

The result of the comparison is a data item containing the following attributes:

• BEqual: boolean, initialized to true if the comparison succeeded, to false otherwise
• NbDiff: integer, containing the number of pixels out of tolerance
• PixCount: integer, containing the number of pixels in each image
• OutOfPixPosition: data-item, containing the coordinates of the first pixel found (if exists), that is out-of-tolerance
• OutOfTolPix1Value: value of the first pixel found (if exists) in the first input image, that is out-of-tolerance
• OutOfTolPix2Value: value of the first pixel found (if exists) in the second input image, that is out-of-tolerance

On output a CompareResult structure is filled.

Example of Python code :

Example imports

import PyIPSDK
import PyIPSDK.IPSDKIPLUtility as util

Code Example

    # opening of input images
    inputGeometry = PyIPSDK.geometry2d(PyIPSDK.eImageBufferType.eIBT_UInt8, 510, 509)
    image1 = PyIPSDK.loadRawImageFile(inputImgPath1,  inputGeometry)
    image2 = PyIPSDK.loadRawImageFile(inputImgPath2,  inputGeometry)
    
    # images comparison
    compareResult = util.compareImg(image1,  image2)
    
    # retrieve comparison results
    bEqual = compareResult.bEqual
    nbDiff = compareResult.nbDiff
    pixCount = compareResult.pixCount

Example of C++ code :

Example informations

Header file

#include <IPSDKIPL/IPSDKIPLUtility/Processor/CompareImg/CompareImg.h>

Code Example

        // opening input images
        ImageGeometryPtr pImageGeometry = geometry2d(imageBufferType, sizeX, sizeY);
        ImagePtr pInImg1 = loadRawImageFile(inputImg1Path, *pImageGeometry);
        ImagePtr pInImg2 = loadRawImageFile(inputImg2Path, *pImageGeometry);
        
        // comparison of images
        CompareResultPtr pCompareResult = compareImg(pInImg1, pInImg2);

        // retrieve comparison results
        const bool bEqual = pCompareResult->getValue<CompareResult::BEqual>();
        const ipUInt64 nbDiff = pCompareResult->getValue<CompareResult::NbDiff>();
        const ipUInt64 pixCount = pCompareResult->getValue<CompareResult::PixCount>();