Manual Pages for UNIX Operating System command usage for man mlib_ImageStdDev

mediaLib Library Functions                mlib_ImageStdDev(3MLIB)



NAME
     mlib_ImageStdDev - image standard deviation

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

     mlib_status mlib_ImageStdDev(mlib_d64 *sdev, const mlib_image *img,
          const mlib_d64 *mean);


DESCRIPTION
     The mlib_ImageStdDev() 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 == NULL,

                   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 NULL, it will be computed.) mean[i] contains the
             mean of channel i.


RETURN VALUES
     The function returns MLIB_SUCCESS if  successful.  Otherwise
     it returns MLIB_FAILURE.





SunOS 5.11           Last change: 2 Mar 2007                    1






mediaLib Library Functions                mlib_ImageStdDev(3MLIB)



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



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|


SEE ALSO
     mlib_ImageMean(3MLIB),             mlib_ImageMean_Fp(3MLIB),
     mlib_ImageStdDev_Fp(3MLIB), attributes(5)





































SunOS 5.11           Last change: 2 Mar 2007                    2