'\" te
.\" Copyright (c) 2007, Sun Microsystems, Inc.  All Rights Reserved 
.TH mlib_ImageThresh4_Fp 3MLIB "2 Mar 2007" "SunOS 5.11" "mediaLib Library Functions"
.SH NAME
mlib_ImageThresh4_Fp \- image thresholding
.SH SYNOPSIS
.LP
.nf
cc [ \fIflag\fR... ] \fIfile\fR... \fB-lmlib\fR [ \fIlibrary\fR... ]
#include <mlib.h>

\fBmlib_status\fR \fBmlib_ImageThresh4_Fp\fR(\fBmlib_image *\fR\fIdst\fR, \fBconst mlib_image *\fR\fIsrc\fR,
     \fBconst mlib_d64 *\fR\fIthigh\fR, \fBconst mlib_d64 *\fR\fItlow\fR, \fBconst mlib_d64 *\fR\fIghigh\fR,
     \fBconst mlib_d64 *\fR\fIglow\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBmlib_ImageThresh4_Fp()\fR function compares each pixel in the source image to two threshold values, \fItlow\fR and \fIthigh\fR. If the pixel is less than the lower threshold value, \fItlow\fR, then the destination pixel is set to the lower output level, \fIglow\fR. If the pixel is greater than the higher threshold value, \fIthigh\fR, then the destination pixel is set to the higher output level, \fIghigh\fR. Otherwise, the destination pixel is set to the value of the source pixel.
.sp
.LP
It uses the following equation:
.sp
.in +2
.nf
dst[x][y][i] = glow[i]       if src[x][y][i] < tlow[i]
dst[x][y][i] = src[x][y][i]  if tlow[i] \(<= src[x][y][i] \(<= thigh[i]
dst[x][y][i] = ghigh[i]      if src[x][y][i] > thigh[i]
.fi
.in -2

.SH PARAMETERS
.sp
.LP
The function takes the following arguments:
.sp
.ne 2
.mk
.na
\fB\fIdst\fR\fR
.ad
.RS 9n
.rt  
Pointer to destination image.
.RE

.sp
.ne 2
.mk
.na
\fB\fIsrc\fR\fR
.ad
.RS 9n
.rt  
Pointer to source image.
.RE

.sp
.ne 2
.mk
.na
\fB\fIthigh\fR\fR
.ad
.RS 9n
.rt  
High threshold value. \fBthigh[i]\fR holds the high threshold for channel \fBi\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fItlow\fR\fR
.ad
.RS 9n
.rt  
Low threshold value. \fBtlow[i]\fR holds the low threshold for channel \fBi\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fIghigh\fR\fR
.ad
.RS 9n
.rt  
High output grayscale level. \fBghigh[i]\fR holds the high output grayscale level for channel \fBi\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fIglow\fR\fR
.ad
.RS 9n
.rt  
Low output grayscale level. \fBglow[i]\fR holds the low output grayscale level for channel \fBi\fR.
.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_ImageThresh1\fR(3MLIB), \fBmlib_ImageThresh1_Fp\fR(3MLIB), \fBmlib_ImageThresh1_Fp_Inp\fR(3MLIB), \fBmlib_ImageThresh1_Inp\fR(3MLIB), \fBmlib_ImageThresh2\fR(3MLIB), \fBmlib_ImageThresh2_Fp\fR(3MLIB), \fBmlib_ImageThresh2_Fp_Inp\fR(3MLIB), \fBmlib_ImageThresh2_Inp\fR(3MLIB), \fBmlib_ImageThresh3\fR(3MLIB), \fBmlib_ImageThresh3_Fp\fR(3MLIB), \fBmlib_ImageThresh3_Fp_Inp\fR(3MLIB), \fBmlib_ImageThresh3_Inp\fR(3MLIB), \fBmlib_ImageThresh4\fR(3MLIB), \fBmlib_ImageThresh4_Fp_Inp\fR(3MLIB), \fBmlib_ImageThresh4_Inp\fR(3MLIB), \fBmlib_ImageThresh5\fR(3MLIB), \fBmlib_ImageThresh5_Fp\fR(3MLIB), \fBmlib_ImageThresh5_Fp_Inp\fR(3MLIB), \fBmlib_ImageThresh5_Inp\fR(3MLIB), \fBattributes\fR(5)