FreeCalypso > hg > freecalypso-hwlab

comparison lunalcd/ppmtoimg.c @ 69:1e6f05ede5ca

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
lunalcd: ppmtoimg utility added
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 07 May 2020 00:12:54 +0000
parents
children
comparison
equal deleted inserted replaced
68:72ff023ec6c9 69:1e6f05ede5ca
1 /*
2 * This program converts a 176x220 pixel wallpaper image from PPM format
3 * into a raw binary image file that will be written into an ad hoc flash
4 * location with fc-loadtool; these images will then be displayed on our
5 * Luna LCD by a standalone target-utils program.
6 */
7
8 #include <stdio.h>
9 #include <ctype.h>
10 #include <stdlib.h>
11
12 static char *ppm_filename;
13 static FILE *ppmfile;
14 static int ppm_is_ascii; /* P3 format instead of P6 */
15
16 /*
17 * This function reads one ASCII-encoded integer from a PPM file.
18 * It handles the white space and comment rules of the PPM format.
19 */
20 static int
21 ppm_get_ascii_number()
22 {
23 int accum, c;
24
25 do {
26 c = getc(ppmfile);
27 if (c < 0) {
28 badeof: fprintf(stderr, "%s: unexpected EOF\n", ppm_filename);
29 return(-1);
30 }
31 if (c == '#') {
32 do
33 c = getc(ppmfile);
34 while (c >= 0 && c != '\n');
35 if (c != '\n')
36 goto badeof;
37 }
38 } while (isspace(c));
39 if (!isdigit(c)) {
40 fprintf(stderr,
41 "%s: unexpected data where a number was expected\n",
42 ppm_filename);
43 return(-1);
44 }
45 for (accum = c - '0'; ; ) {
46 c = getc(ppmfile);
47 if (c < 0 || isspace(c))
48 break;
49 if (!isdigit(c)) {
50 fprintf(stderr,
51 "%s: bad character in the middle of a number\n",
52 ppm_filename);
53 return(-1);
54 }
55 accum = accum * 10 + c - '0';
56 }
57 return accum;
58 }
59
60 /*
61 * This function reads and parses the PPM header of our input file.
62 */
63 static int
64 ppm_read_header()
65 {
66 int magic1, magic2;
67 int rd;
68
69 magic1 = getc(ppmfile);
70 magic2 = getc(ppmfile);
71 if (magic1 == 'P' && magic2 == '3')
72 ppm_is_ascii = 1;
73 else if (magic1 == 'P' && magic2 == '6')
74 ppm_is_ascii = 0;
75 else {
76 fprintf(stderr, "%s: P3 or P6 format expected\n", ppm_filename);
77 return(-1);
78 }
79 rd = ppm_get_ascii_number();
80 if (rd < 0)
81 return(-1);
82 if (rd != 176) {
83 fprintf(stderr, "%s: width is not 176\n", ppm_filename);
84 return(-1);
85 }
86 rd = ppm_get_ascii_number();
87 if (rd < 0)
88 return(-1);
89 if (rd != 220) {
90 fprintf(stderr, "%s: height is not 220\n", ppm_filename);
91 return(-1);
92 }
93 rd = ppm_get_ascii_number();
94 if (rd < 0)
95 return(-1);
96 if (rd != 255) {
97 fprintf(stderr, "%s: maxval is not 255\n", ppm_filename);
98 return(-1);
99 }
100 return(0);
101 }
102
103 /*
104 * This function reads a single R, G or B value from a PPM file.
105 */
106 static int
107 ppm_get_pixval()
108 {
109 int c;
110
111 if (ppm_is_ascii)
112 return ppm_get_ascii_number();
113 c = getc(ppmfile);
114 if (c < 0) {
115 fprintf(stderr, "%s: EOF while reading binary pixel data\n",
116 ppm_filename);
117 return(-1);
118 }
119 return c;
120 }
121
122 static int
123 ppm_get_rgb()
124 {
125 int r, g, b;
126
127 r = ppm_get_pixval();
128 if (r < 0)
129 return(-1);
130 g = ppm_get_pixval();
131 if (g < 0)
132 return(-1);
133 b = ppm_get_pixval();
134 if (b < 0)
135 return(-1);
136 /* convert to 5:6:5 */
137 r >>= 3;
138 g >>= 2;
139 b >>= 3;
140 return (r << 11) | (g << 5) | b;
141 }
142
143 main(argc, argv)
144 char **argv;
145 {
146 FILE *of;
147 int rc;
148 unsigned n;
149
150 if (argc != 3) {
151 fprintf(stderr, "usage: %s ppmfile binfile\n", argv[0]);
152 exit(1);
153 }
154 ppm_filename = argv[1];
155 ppmfile = fopen(ppm_filename, "r");
156 if (!ppmfile) {
157 perror(ppm_filename);
158 exit(1);
159 }
160 rc = ppm_read_header();
161 if (rc < 0)
162 exit(1);
163 of = fopen(argv[2], "w");
164 if (!of) {
165 perror(argv[2]);
166 exit(1);
167 }
168 for (n = 0; n < 176*220; n++) {
169 rc = ppm_get_rgb();
170 if (rc < 0)
171 exit(1);
172 putc(rc & 0xFF, of);
173 putc(rc >> 8, of);
174 }
175 fclose(of);
176 exit(0);
177 }