Check for SYS/GL during library init. Reason is that
[AROS.git] / workbench / libs / png / contrib / examples / iccfrompng.c
blob67676219e658f5071b34ff28490160b766268df8
1 /*- iccfrompng
3 * COPYRIGHT: Written by John Cunningham Bowler, 2011.
4 * To the extent possible under law, the author has waived all copyright and
5 * related or neighboring rights to this work. This work is published from:
6 * United States.
8 * Extract any icc profiles found in the given PNG files. This is a simple
9 * example of a program which extracts information from the header of a PNG file
10 * without processing the image. Notice that some header information may occur
11 * after the image data, textual data and comments are an example; the approach
12 * in this file won't work reliably for such data because it only looks for the
13 * information in the section of the file that preceeds the image data.
15 * Compile and link against libpng and zlib, plus anything else required on the
16 * system you use.
18 * To use supply a list of PNG files containing iCCP chunks, the chunks will be
19 * extracted to a similarly named file with the extension replaced by 'icc',
20 * which will be overwritten without warning.
22 #include <stdlib.h>
23 #include <setjmp.h>
24 #include <string.h>
25 #include <stdio.h>
27 #include <png.h>
29 static int verbose = 1;
30 static png_byte no_profile[] = "no profile";
32 static png_bytep
33 extract(FILE *fp, png_uint_32 *proflen)
35 png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
36 png_infop info_ptr = NULL;
37 png_bytep result = NULL;
39 /* Initialize for error or no profile: */
40 *proflen = 0;
42 if (png_ptr == NULL)
44 fprintf(stderr, "iccfrompng: version library mismatch?\n");
45 return 0;
48 if (setjmp(png_jmpbuf(png_ptr)))
50 png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
51 return 0;
54 png_init_io(png_ptr, fp);
56 info_ptr = png_create_info_struct(png_ptr);
57 if (info_ptr == NULL)
58 png_error(png_ptr, "OOM allocating info structure");
60 png_read_info(png_ptr, info_ptr);
63 png_charp name;
64 int compression_type;
65 png_bytep profile;
67 if (png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, &profile,
68 proflen) & PNG_INFO_iCCP)
70 result = malloc(*proflen);
71 if (result != NULL)
72 memcpy(result, profile, *proflen);
74 else
75 png_error(png_ptr, "OOM allocating profile buffer");
78 else
79 result = no_profile;
82 png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
83 return result;
86 static int
87 extract_one_file(const char *filename)
89 int result = 0;
90 FILE *fp = fopen(filename, "rb");
92 if (fp != NULL)
94 png_uint_32 proflen = 0;
95 png_bytep profile = extract(fp, &proflen);
97 if (profile != NULL && profile != no_profile)
99 size_t len;
100 char *output;
103 const char *ep = strrchr(filename, '.');
105 if (ep != NULL)
106 len = ep-filename;
108 else
109 len = strlen(filename);
112 output = malloc(len + 5);
113 if (output != NULL)
115 FILE *of;
117 memcpy(output, filename, len);
118 strcpy(output+len, ".icc");
120 of = fopen(output, "wb");
121 if (of != NULL)
123 if (fwrite(profile, proflen, 1, of) == 1 &&
124 fflush(of) == 0 &&
125 fclose(of) == 0)
127 if (verbose)
128 printf("%s -> %s\n", filename, output);
129 /* Success return */
130 result = 1;
133 else
135 fprintf(stderr, "%s: error writing profile\n", output);
136 if (remove(output))
137 fprintf(stderr, "%s: could not remove file\n", output);
141 else
142 fprintf(stderr, "%s: failed to open output file\n", output);
144 free(output);
147 else
148 fprintf(stderr, "%s: OOM allocating string!\n", filename);
150 free(profile);
153 else if (verbose && profile == no_profile)
154 printf("%s has no profile\n", filename);
157 else
158 fprintf(stderr, "%s: could not open file\n", filename);
160 return result;
164 main(int argc, char **argv)
166 int i;
167 int extracted = 0;
169 for (i=1; i<argc; ++i)
171 if (strcmp(argv[i], "-q") == 0)
172 verbose = 0;
174 else if (extract_one_file(argv[i]))
175 extracted = 1;
178 /* Exit code is true if any extract succeeds */
179 return extracted == 0;