1 /* wbmptopbm.c - convert a wbmp file to a portable bitmap
2
3 This is derived for Netpbm from the pbmwbmp package from
4 <http://www.looplab.com/wap/tools> on 2000.06.06.
5
6 The specifications for the wbmp format are part of the Wireless
7 Application Environment specification at
8 <http://www.wapforum.org/what/technical.htm>.
9
10 ** Copyright (C) 1999 Terje Sannum <terje@looplab.com>.
11 **
12 ** Permission to use, copy, modify, and distribute this software and its
13 ** documentation for any purpose and without fee is hereby granted, provided
14 ** that the above copyright notice appear in all copies and that both that
15 ** copyright notice and this permission notice appear in supporting
16 ** documentation. This software is provided "as is" without express or
17 ** implied warranty.
18 */
19
20 #include "pbm.h"
21
22 static int
readc(FILE * f)23 readc(FILE *f) {
24 int c = fgetc(f);
25 if(c == EOF) pm_error("EOF / read error");
26 return c;
27 }
28
29
30
31 static int
readint(FILE * f)32 readint(FILE *f) {
33 int c=0, pos=0, sum=0;
34 do {
35 c = readc(f);
36 sum = (sum << 7*pos++) | (c & 0x7f);
37 } while(c & 0x80);
38 return sum;
39 }
40
41
42
43 static void
readheader(int h,FILE * f)44 readheader(int h, FILE *f) {
45 int c,i;
46 switch(h & 0x60) {
47 case 0x00:
48 /* Type 00: read multi-byte bitfield */
49 do c=readc(f); while(c & 0x80);
50 break;
51 case 0x60:
52 /* Type 11: read name/value pair */
53 for(i=0; i < ((h & 0x70) >> 4) + (h & 0x0f); i++) c=readc(f);
54 break;
55 }
56 }
57
58
59
60 static bit **
readwbmp(FILE * f,int * cols,int * rows)61 readwbmp(FILE *f, int *cols, int *rows) {
62 int i,j,k,row,c;
63 bit **image;
64 /* Type */
65 c = readint(f);
66 if(c != 0) pm_error("Unrecognized WBMP type");
67 /* Headers */
68 c = readc(f); /* FixHeaderField */
69 while(c & 0x80) { /* ExtHeaderFields */
70 c = readc(f);
71 readheader(c, f);
72 }
73 /* Geometry */
74 *cols = readint(f);
75 *rows = readint(f);
76 image = pbm_allocarray(*cols, *rows);
77 /* read image */
78 row = *cols/8;
79 if(*cols%8) row +=1;
80 for(i=0; i<*rows; i++) {
81 for(j=0; j<row; j++) {
82 c=readc(f);
83 for(k=0; k<8 && j*8+k<*cols; k++) {
84 image[i][j*8+k] = c & (0x80 >> k) ? PBM_WHITE : PBM_BLACK;
85 }
86 }
87 }
88 return image;
89 }
90
91
92
93 int
main(int argc,char * argv[])94 main(int argc, char *argv[]) {
95 FILE *f;
96 bit **image;
97 int rows, cols;
98
99 pbm_init(&argc, argv);
100 if(argc > 2) {
101 fprintf(stderr, "Copyright (C) 1999 Terje Sannum <terje@looplab.com>\n");
102 pm_usage("[wbmpfile]");
103 }
104
105 f = argc == 2 ? pm_openr(argv[1]) : stdin;
106 image = readwbmp(f, &cols, &rows);
107 pm_close(f);
108 pbm_writepbm(stdout, image, cols, rows, 0);
109 pm_close(stdout);
110 return 0;
111 }
112
113