'\" te
.\" Copyright (c) 2007, Sun Microsystems, Inc.  All Rights Reserved 
.TH mlib_ImageExtrema2 3MLIB "2 Mar 2007" "SunOS 5.11" "mediaLib Library Functions"
.SH NAME
mlib_ImageExtrema2, mlib_ImageExtrema2_Fp \- image extrema
.SH SYNOPSIS
.LP
.nf
cc [ \fIflag\fR... ] \fIfile\fR... \fB-lmlib\fR [ \fIlibrary\fR... ]
#include <mlib.h>

\fBmlib_status\fR \fBmlib_ImageExtrema2\fR(\fBmlib_s32 *\fR\fImin\fR, \fBmlib_s32 *\fR\fImax\fR,
     \fBconst mlib_image *\fR\fIimg\fR, \fBmlib_s32\fR \fIxStart\fR, \fBmlib_s32\fR \fIyStart\fR,
     \fBmlib_s32\fR \fIxPeriod\fR, \fBmlib_s32\fR \fIyPeriod\fR);
.fi

.LP
.nf
\fBmlib_status\fR \fBmlib_ImageExtrema2_Fp\fR(\fBmlib_d64 *\fR\fImin\fR, \fBmlib_d64 *\fR\fImax\fR,
     \fBconst mlib_image *\fR\fIimg\fR, \fBmlib_s32\fR \fIxStart\fR, \fBmlib_s32\fR \fIyStart\fR,
     \fBmlib_s32\fR \fIxPeriod\fR, \fBmlib_s32\fR \fIyPeriod\fR);
.fi

.SH DESCRIPTION
.sp
.LP
Each of the functions determines the extrema values for each channel in an image, possibly with subsampling.
.sp
.LP
It uses the following equation:
.sp
.in +2
.nf
min[i] = MIN{ img[x][y][i] }
max[i] = MAX{ img[x][y][i] }
.fi
.in -2

.sp
.LP
where
.sp
.in +2
.nf
x = xStart + p*xPeriod;  0 \(<= p < (w - xStart)/xPeriod
y = yStart + q*yPeriod;  0 \(<= q < (h - yStart)/yPeriod
.fi
.in -2

.SH PARAMETERS
.sp
.LP
Each of the functions takes the following arguments:
.sp
.ne 2
.mk
.na
\fB\fImin\fR\fR
.ad
.RS 11n
.rt  
Pointer to minimum vector, where length is the number of channels in the image. \fBmin[i]\fR contains the minimum of channel \fBi\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fImax\fR\fR
.ad
.RS 11n
.rt  
Pointer to maximum vector, where length is the number of channels in the image. \fBmax[i]\fR contains the maximum of channel \fBi\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fIimg\fR\fR
.ad
.RS 11n
.rt  
Pointer to a source image.
.RE

.sp
.ne 2
.mk
.na
\fB\fIxStart\fR\fR
.ad
.RS 11n
.rt  
Initial X sample coordinate.
.RE

.sp
.ne 2
.mk
.na
\fB\fIyStart\fR\fR
.ad
.RS 11n
.rt  
Initial Y sample coordinate.
.RE

.sp
.ne 2
.mk
.na
\fB\fIxPeriod\fR\fR
.ad
.RS 11n
.rt  
 X sample rate. \fBxPeriod \(>= 1\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fIyPeriod\fR\fR
.ad
.RS 11n
.rt  
 Y sample rate. \fByPeriod \(>= 1\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_ImageExtremaLocations\fR(3MLIB), \fBmlib_ImageMaximum\fR(3MLIB), \fBmlib_ImageMaximum_Fp\fR(3MLIB), \fBmlib_ImageMinimum\fR(3MLIB), \fBmlib_ImageMinimum_Fp\fR(3MLIB), \fBattributes\fR(5)