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
|
/*
* Copyright (c) 2014, Mathieu Malaterre <mathieu.malaterre@voxxl.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Technically on UNIX, one can simply call `ppmtorgb3`, but on my system it
* did not work. So I had to write my own.
*/
#include <stdio.h> /* fprintf */
#include <string.h> /* strcmp */
#include <stdlib.h> /* malloc */
static const char magic[] = "P6";
static int readheader( FILE *ppm, int *X, int *Y, int *bpp )
{
char buffer[256];
char strbuffer[256];
char *line;
int n;
*X = *Y = *bpp = 0;
line = fgets(buffer, sizeof(buffer), ppm);
if( !line ) return 0;
n = sscanf(buffer, "%255[^\r\n]", strbuffer);
if( n != 1 ) return 0;
if( strcmp(strbuffer, magic ) != 0 ) return 0;
/* skip comments */
while( fgets(buffer, sizeof(buffer), ppm) && *buffer == '#' )
{
}
n = sscanf(buffer, "%d %d", X,Y);
if( n != 2 ) return 0;
line = fgets(buffer, sizeof(buffer), ppm);
if( !line ) return 0;
n = sscanf(buffer, "%d", bpp);
if( n != 1 ) return 0;
if( *bpp != 255 ) return 0;
return 1;
}
static int writeoutput( const char *fn, FILE *ppm, int X, int Y, int bpp )
{
FILE *outf[] = {NULL, NULL, NULL};
int i, x, y = 0;
char outfn[256];
static const char *exts[3] = {
"red",
"grn",
"blu"
};
char *image_line = NULL;
int ok = 0;
/* write single comp as PGM: P5 */
for( i = 0; i < 3; ++i )
{
#ifdef _MSC_VER
#define snprintf _snprintf /* Visual Studio */
#endif
snprintf( outfn, sizeof(outfn), "%s.%s.pgm", fn, exts[i] );
outf[i] = fopen( outfn, "wb" );
if( !outf[i] ) goto cleanup;
/* write header */
fprintf( outf[i], "P5\n" );
fprintf( outf[i], "%d %d\n", X, Y );
fprintf( outf[i], "%d\n", bpp );
}
/* write pixel data */
image_line = (char*)malloc( (size_t)X * 3 * sizeof(char) );
if( !image_line ) goto cleanup;
while( fread(image_line, sizeof(char), (size_t)X * 3, ppm) == (size_t)X * 3 )
{
for( x = 0; x < X; ++x )
for( i = 0; i < 3; ++i )
if( fputc( image_line[3*x+i], outf[i] ) == EOF ) goto cleanup;
++y;
}
if( y == Y )
ok = 1;
cleanup:
free(image_line);
for( i = 0; i < 3; ++i )
if( outf[i] ) fclose( outf[i] );
return ok;
}
int main(int argc, char *argv[])
{
const char *fn;
FILE *ppm = NULL;
int X, Y, bpp;
int ok = 0;
if( argc < 2 )
{
fprintf( stderr, "%s input.ppm\n", argv[0] );
goto cleanup;
}
fn = argv[1];
ppm = fopen( fn, "rb" );
if( !readheader( ppm, &X, &Y, &bpp ) ) goto cleanup;
if( !writeoutput(fn, ppm, X, Y, bpp ) ) goto cleanup;
ok = 1;
cleanup:
if(ppm) fclose(ppm);
return ok ? EXIT_SUCCESS : EXIT_FAILURE;
}
|
