AddRandUniform

Generates random samples with uniform distribution and adds them to an image data.

Syntax

IppStatus ippiAddRandUniform_Direct_<mod>(Ipp<datatype>* pSrcDst, int srcDstStep, IppiSize roiSize, Ipp<datatype> low, Ipp<datatype> high, unsigned int* pSeed);

Supported values for mod:

8u_C1IR	16u_C1IR	16s_C1IR	32f_C1IR
8u_C3IR	16u_C3IR	16s_C3IR	32f_C3IR
8u_C4IR	16u_C4IR	16s_C4IR	32f_C4IR
8u_AC4IR	16u_AC4IR	16s_AC4IR	32f_AC4IR

Parameters

pSrcDst	Pointer to the source and destination image ROI.
srcDstStep	Distance in bytes between starts of consecutive lines in the source and destination image.
roiSize	Size of the image ROI in pixels.
low	The lower bound for the range of uniformly distributed values.
high	The upper bound for the range of uniformly distributed values.
pSeed	The initial seed value for the pseudo-random number generator.

Description

The function ippiAddRandUniform_Direct is declared in the ippi.h file. It operates with ROI (see Regions of Interest in Intel IPP).

The function generates samples with uniform distribution over the range [low, high] and adds them to a source image pointed to by pSrcDst.

The resulting pixel values that exceed the image data range are saturated to the respective data-range limits. To obtain an image that contains pure noise with uniform distribution, call ippiAddRandUniform_Direct using a source image with zero data as input.

Example “Random Samples Generating” shows data conversion without scaling.

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 srcDstStep has a zero or negative value.

Random Samples Generating

      IppStatus randUniform( void ) {
         unsigned int seed = 123456;
         Ipp8u img[2048], mn, mx;
         IppiSize roi={2048,1};
         Ipp64f mean;
         IppStatus st;
         ippiSet_8u_C1R( 0, img, 2048, roi );
         st = ippiAddRandUniform_Direct_8u_C1IR(img, 2048, roi, 0, 255, &seed);
         ippiMean_8u_C1R( img, 2048, roi, &mean );
         ippiMinMax_8u_C1R( img, 2048, roi, &mn, &mx );
         printf( "[%d..%d], mean=%.3f\n", mn, mx, mean );
         return st;
      }