mlib_ImageMulAlpha(3MLIB) mediaLib Library Functions mlib_ImageMulAlpha(3MLIB)NAME
mlib_ImageMulAlpha - alpha channel multiplication
SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ]
#include <mlib.h>
mlib_status mlib_ImageMulAlpha(mlib_image *dst, const mlib_image *src,
mlib_s32 cmask);
DESCRIPTION
The mlib_ImageMulAlpha() function multiplies color channels by the alpha channel on a pixel by pixel basis.
For the MLIB_BYTE image, it uses the following equation:
dst[x][y][c] = src[x][y][c] * src[x][y][a] * 2**(-8)
For the MLIB_SHORT image, it uses the following equation:
dst[x][y][c] = src[x][y][c] * src[x][y][a] * 2**(-15)
For the MLIB_USHORT image, it uses the following equation:
dst[x][y][c] = src[x][y][c] * src[x][y][a] * 2**(-16)
For the MLIB_INT image, it uses the following equation:
dst[x][y][c] = src[x][y][c] * src[x][y][a] * 2**(-31)
where c and a are the indices for the color channels and the alpha channel, respectively, so c != a.
PARAMETERS
The function takes the following arguments:
dst Pointer to destination image.
src Pointer to source image.
cmask Channel mask to indicate the alpha channel. Each bit of the mask represents a channel in the image. The channel corresponding to
the 1 bit of cmask is the alpha channel.
RETURN VALUES
The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Committed |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
SEE ALSO mlib_ImageMulAlpha_Inp(3MLIB), mlib_ImageMulAlpha_Fp(3MLIB), mlib_ImageMulAlpha_Fp_Inp(3MLIB), attributes(5)SunOS 5.11 2 Mar 2007 mlib_ImageMulAlpha(3MLIB)