mediaLib Library Functions                 mlibImageBlend(3MLIB)



NAME
     mlibImageBlend - blend with an alpha image

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

     mlibstatus mlibImageBlend(mlibimage *dst, const mlibimage *src1,
          const mlibimage *src2, const mlibimage *alpha);


DESCRIPTION
     The mlibImageBlend() function blends two images together on
     a  pixel-by-pixel  basis using an alpha image, when alpha is
     also on a pixel basis. The alpha  image  can  be  a  single-
     channel  image  or  have  the same number of channels as the
     source and destination images.


     It uses the following equation when the  alpha  image  is  a
     single-channel image:

       dst[x][y][i] = a[x][y][0]*src1[x][y][i] ]
                      (1 - a[x][y][0])*src2[x][y][i]



     It uses the following equation when the alpha image has  the
     same  number  of  channels  as  the  source  and destination
     images:

       dst[x][y][i] = a[x][y][i]*src1[x][y][i] ]
                      (1 - a[x][y][i])*src2[x][y][i]


PARAMETERS
     The function takes the following arguments:

     dst      Pointer to destination image.


     src1     Pointer to first source image.


     src2     Pointer to second source image.


     alpha    Alpha image used to control blending. The  a  value
              equals  (alpha  *  2**(-8))  for  MLIBYTE  image,
              (alpha * 2**(-15)) for MLIBSHORT image,  (alpha  *
              2**(-16))  for  MLIBUSHORT  image,  and  (alpha  *
              2**(-31)) for MLIBINT image.



SunOS 5.11           Last change: 2 Mar 2007                    1






mediaLib Library Functions                 mlibImageBlend(3MLIB)



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

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



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


SEE ALSO
     mlibImageBlendFp(3MLIB),   mlibImageBlend1FpInp(3MLIB),
     mlibImageBlend1Inp(3MLIB), mlibImageBlend2FpInp(3MLIB),
     mlibImageBlend2Inp(3MLIB), attributes(5)
































SunOS 5.11           Last change: 2 Mar 2007                    2