1mlib_ImageStdDev_Fp(3MLIB)mediaLib Library Functionsmlib_ImageStdDev_Fp(3MLIB)
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NAME

6       mlib_ImageStdDev_Fp - image standard deviation
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SYNOPSIS

9       cc [ flag... ] file... -lmlib [ library... ]
10       #include <mlib.h>
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12       mlib_status mlib_ImageStdDev_Fp(mlib_d64 *sdev, const mlib_image *img,
13            const mlib_d64 *mean);
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DESCRIPTION

17       The  mlib_ImageStdDev_Fp() function computes the standard deviation for
18       each channel in the floating-point source image.
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21       It uses the following equation:
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23                       1     w-1 h-1
24         sdev[i] = { ----- * SUM SUM (img[x][y][i] - mean[i])**2 }**0.5
25                      w*h    x=0 y=0
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29       where, in the case of mean == NULL,
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31                     1     w-1 h-1
32         mean[i] = ----- * SUM SUM img[x][y][i]
33                    w*h    x=0 y=0
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PARAMETERS

37       The function takes the following arguments:
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39       sdev    Pointer to standard deviation array, whose size is  the  number
40               of  channels in the source image. sdev[i] contains the standard
41               deviation of channel i.
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44       img     Pointer to input image.
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47       mean    Pointer to pre-computed mean array for each channel. (If  NULL,
48               it will be computed.) mean[i] contains the mean of channel i.
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RETURN VALUES

52       The  function  returns MLIB_SUCCESS if successful. Otherwise it returns
53       MLIB_FAILURE.
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ATTRIBUTES

56       See attributes(5) for descriptions of the following attributes:
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61       ┌─────────────────────────────┬─────────────────────────────┐
62       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
63       ├─────────────────────────────┼─────────────────────────────┤
64       │Interface Stability          │Committed                    │
65       ├─────────────────────────────┼─────────────────────────────┤
66       │MT-Level                     │MT-Safe                      │
67       └─────────────────────────────┴─────────────────────────────┘
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SEE ALSO

70       mlib_ImageMean(3MLIB),     mlib_ImageMean_Fp(3MLIB),     mlib_ImageStd‐
71       Dev(3MLIB), attributes(5)
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75SunOS 5.11                        2 Mar 2007        mlib_ImageStdDev_Fp(3MLIB)
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