1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154
|
/* @(#) Slices an image using two thresholds. Works for any non-complex type.
* @(#) Output has three levels 0 128 and 255. Values below or = t1 are 0,
* @(#) above t2 are 255 and the remaining are 128.
* @(#) Input is either memory mapped or in a buffer.
* @(#) It is implied that t1 is less than t2; however the program checks
* @(#) if they are the wrong way and swaps them
* @(#)
* @(#) int im_slice(in, out, t1, t2)
* @(#) IMAGE *in, *out;
* @(#) double t1, t2;
* @(#)
* @(#) Returns 0 on success and -1 on error
*
* Copyright: 1991, N. Dessipris
*
* Author: N. Dessipris
* Written on: 15/03/1991
* Modified on :
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include <vips/vips7compat.h>
#define BRIGHT 255
#define GREY 128
#define DARK 0
/* Useful: Call a macro with the name, type pairs for all VIPS functions.
*/
#define im_for_all_types(A) \
case IM_BANDFMT_UCHAR: A(unsigned char); break; \
case IM_BANDFMT_CHAR: A(signed char); break; \
case IM_BANDFMT_USHORT: A(unsigned short); break; \
case IM_BANDFMT_SHORT: A(signed short); break; \
case IM_BANDFMT_UINT: A(unsigned int); break; \
case IM_BANDFMT_INT: A(signed int); break; \
case IM_BANDFMT_FLOAT: A(float); break;
/* Replacement for im_slice */
int
im_slice( in, out, t1, t2 )
IMAGE *in, *out;
double t1, t2;
{
int x, y, z;
PEL *bu; /* Buffer we write to */
int s, epl; /* Size and els per line */
double thresh1, thresh2;
/* Check our args. */
if( im_iocheck( in, out ) )
{
im_error( "im_slice", "%s", _( "im_iocheck failed") );
return( -1 );
}
if( in->Coding != IM_CODING_NONE )
{
im_error( "im_slice", "%s", _( "input should be uncoded") );
return( -1 );
}
/* Set up the output header. */
if( im_cp_desc( out, in ) )
{
im_error( "im_slice", "%s", _( "im_cp_desc failed") );
return( -1 );
}
out->BandFmt = IM_BANDFMT_UCHAR;
if( im_setupout( out ) )
{
im_error( "im_slice", "%s", _( "im_setupout failed") );
return( -1 );
}
if ( t1 <= t2 )
{ thresh1 = t1; thresh2 = t2; }
else
{ thresh1 = t2; thresh2 = t1; }
/* Make buffer for building o/p in. */
epl = in->Xsize * in->Bands;
s = epl * sizeof( PEL );
if( (bu = (PEL *) im_malloc( out, (unsigned)s )) == NULL )
return( -1 );
/* Define what we do for each band element type. */
#define im_slice_loop(TYPE)\
{ TYPE *a = (TYPE *) in->data;\
\
for( y = 0; y < in->Ysize; y++ ) {\
PEL *b = bu;\
\
for( x = 0; x < in->Xsize; x++ )\
for( z = 0; z < in->Bands; z++ ) {\
double f = (double) *a++;\
if ( f <= thresh1)\
*b++ = (PEL)DARK;\
else if ( f > thresh2 )\
*b++ = (PEL)BRIGHT;\
else \
*b++ = (PEL)GREY;\
}\
\
if( im_writeline( y, out, bu ) )\
return( -1 );\
}\
}
/* Do the above for all image types. */
switch( in->BandFmt ) {
im_for_all_types( im_slice_loop );
default:
im_error( "im_slice", "%s", _( "Unknown input format") );
return( -1 );
}
return( 0 );
}
|