'\" te
.\" Copyright (c) 2007, Sun Microsystems, Inc.  All Rights Reserved 
.TH mlib_ImageColorOrderedDither8x8 3MLIB "2 Mar 2007" "SunOS 5.11" "mediaLib Library Functions"
.SH NAME
mlib_ImageColorOrderedDither8x8 \- true color to indexed color conversion using ordered dithering
.SH SYNOPSIS
.LP
.nf
cc [ \fIflag\fR... ] \fIfile\fR... \fB-lmlib\fR [ \fIlibrary\fR... ]
#include <mlib.h>

\fBmlib_status\fR \fB\fR(\fBmlib_image *\fR\fIdst\fR, \fBconst mlib_image *\fR\fIsrc\fR, \fBconst mlib_s32 *\fR\fIdmask\fR,
     \fBmlib_s32\fR \fIscale\fR, \fBconst void *\fR\fIcolormap\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBmlib_ImageColorOrderedDither8x8()\fR function converts a true color image to a pseudo color image with the method of ordered dithering. The source image can be an \fBMLIB_BYTE\fR or \fBMLIB_SHORT\fR image with three or four channels. The destination must be a single-channel \fBMLIB_BYTE\fR or \fBMLIB_SHORT\fR image.
.sp
.LP
This function works only with a colorcube, rather than a general lookup table. The last parameter, \fIcolormap\fR, is an internal data structure (which may include a colorcube) for inverse color mapping. Create it by calling the \fBmlib_ImageColorTrue2IndexInit()\fR function.
.SH PARAMETERS
.sp
.LP
The function takes the following arguments:
.sp
.ne 2
.mk
.na
\fB\fIdst\fR\fR
.ad
.RS 12n
.rt  
Pointer to destination or destination image.
.RE

.sp
.ne 2
.mk
.na
\fB\fIsrc\fR\fR
.ad
.RS 12n
.rt  
Pointer to source or source image.
.RE

.sp
.ne 2
.mk
.na
\fB\fIdmask\fR\fR
.ad
.RS 12n
.rt  
Pointer to the 8x8 dither mask, in row major order. The dither mask is transposed differently for different channels to reduce artifacts.
.RE

.sp
.ne 2
.mk
.na
\fB\fIscale\fR\fR
.ad
.RS 12n
.rt  
Scaling factor for dmask to convert the input integer coefficients into floating-point coefficients:
.sp
.in +2
.nf
floating-point coefficient = integer coefficient * \e
2**(-scale)
.fi
.in -2

.RE

.sp
.ne 2
.mk
.na
\fB\fIcolormap\fR\fR
.ad
.RS 12n
.rt  
Internal data structure for inverse color mapping.
.RE

.SH RETURN VALUES
.sp
.LP
The function returns \fBMLIB_SUCCESS\fR if successful. Otherwise it returns \fBMLIB_FAILURE\fR.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
MT-LevelMT-Safe
.TE

.SH SEE ALSO
.sp
.LP
\fBmlib_ImageColorErrorDiffusion3x3\fR(3MLIB), \fBmlib_ImageColorTrue2Index\fR(3MLIB), \fBmlib_ImageColorTrue2IndexFree\fR(3MLIB), \fBmlib_ImageColorTrue2IndexInit\fR(3MLIB), \fBattributes\fR(5)