mediaLib Library Functions                mlibImageStdDev(3MLIB)



NAME
     mlibImageStdDev - image standard deviation

SYNOPSIS
     cc [ flag... ] file... -lmlib [ library... ]
     #include 

     mlibstatus mlibImageStdDev(mlibd64 *sdev, const mlibimage *img,
          const mlibd64 *mean);


DESCRIPTION
     The mlibImageStdDev() function computes the standard devia-
     tion for each channel in the source image.


     It uses the following equation:

                     1     w-1 h-1
       sdev[i] = { ----- * SUM SUM (img[x][y][i] - mean[i])**2 }**0.5
                    w*h    x=0 y=0



     where, in the case of mean == NUL,

                   1     w-1 h-1
       mean[i] = ----- * SUM SUM img[x][y][i]
                  w*h    x=0 y=0


PARAMETERS
     The function takes the following arguments:

     sdev    Pointer to standard deviation array, whose  size  is
             the  number of channels in the source image. sdev[i]
             contains the standard deviation of channel i.


     img     Pointer to input image.


     mean    Pointer to pre-computed mean array for each channel.
             (If NUL, it will be computed.) mean[i] contains the
             mean of channel i.


RETURN VALUES
     The function returns MLIBSUCES if  successful.  Otherwise
     it returns MLIBFAILURE.





SunOS 5.11           Last change: 2 Mar 2007                    1






mediaLib Library Functions                mlibImageStdDev(3MLIB)



ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Committed                   
    
     MT-Level                     MT-Safe                     
    


SEE ALSO
     mlibImageMean(3MLIB),             mlibImageMeanFp(3MLIB),
     mlibImageStdDevFp(3MLIB), attributes(5)





































SunOS 5.11           Last change: 2 Mar 2007                    2