QualityIndex

Syntax

Parameters

pSrc1, pSrc2	Pointers to the source images ROI.
src1Step, src2Step	Distance in bytes between starts of consecutive lines in the source images.
roiSize	Size of the source ROI in pixels.
pQualityIndex	Pointer to the computed quality index value.
qualityIndex	An array containing the computed quality index values for separate channels in case of multi-channel data.

Description

The function ippiQualityIndex is declared in the ippi.h file. It operates with ROI (see Regions of Interest in Intel IPP). This function computes the universal image quality index for two images pSrc1 and pSrc2 according to the formula in the introduction section above.The computed value of the index for one-channel image is stored in pQualityIndex. For multi-channel images, the quality index is computed separately for each channel and stored in the array qualityIndex.

Example “Using of the function ippiQualityIndex” shows how to use the function ippiQualityIndex_32f_C1R.

Return Values

ippStsNoErr	Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr	Indicates an error when any of the specified pointers is NULL.
ippStsSizeErr	Indicates an error condition if roiSize has a field with zero or negative value.
ippStsStepErr	Indicates an error condition if src1Step or src2Step has a zero or negative value.
ippStsQualityIndexErr	Indicates an error condition if pixel values of one of the images are constatnt.
ippStsMemAllocErr	Indicates an error condition if memory allocation fails.

Using of the function ippiQualityIndex

void func_qualityindex()

{

    Ipp32f pSrc1[256*256];

    Ipp32f pSrc2[256*256];

    int src1Step = 256*sizeof(Ipp32f);

    int src2Step = 256*sizeof(Ipp32f);;

    Ipp32f pQIndex;

    IppiSize roiSize = {256,256};

    unsigned int pSeed = 3;

// creating reference image (image1) and distorted image (image2)

    ippiImageJaehne_32f_C1R(pSrc1, src1Step, roiSize); // image1

    ippiImageJaehne_32f_C1R(pSrc2, src2Step, roiSize); 

    ippiAddRandUniform_Direct_32f_C1IR(pSrc2, src2Step, roiSize, 0, 1, &pSeed);

//image2 = image1 + RandUniform

    ippiQualityIndex_32f_C1R(pSrc1, src1Step, pSrc2, src2Step, roiSize, 

                            
 &pQIndex);

}