| /*- iccfrompng |
| * |
| * COPYRIGHT: Written by John Cunningham Bowler, 2011. |
| * To the extent possible under law, the author has waived all copyright and |
| * related or neighboring rights to this work. This work is published from: |
| * United States. |
| * |
| * Extract any icc profiles found in the given PNG files. This is a simple |
| * example of a program that extracts information from the header of a PNG file |
| * without processing the image. Notice that some header information may occur |
| * after the image data. Textual data and comments are an example; the approach |
| * in this file won't work reliably for such data because it only looks for the |
| * information in the section of the file that preceeds the image data. |
| * |
| * Compile and link against libpng and zlib, plus anything else required on the |
| * system you use. |
| * |
| * To use supply a list of PNG files containing iCCP chunks, the chunks will be |
| * extracted to a similarly named file with the extension replaced by 'icc', |
| * which will be overwritten without warning. |
| */ |
| #include <stdlib.h> |
| #include <setjmp.h> |
| #include <string.h> |
| #include <stdio.h> |
| |
| #include <png.h> |
| |
| #if defined(PNG_READ_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) && \ |
| defined (PNG_iCCP_SUPPORTED) |
| |
| |
| static int verbose = 1; |
| static png_byte no_profile[] = "no profile"; |
| |
| static png_bytep |
| extract(FILE *fp, png_uint_32 *proflen) |
| { |
| png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0); |
| png_infop info_ptr = NULL; |
| png_bytep result = NULL; |
| |
| /* Initialize for error or no profile: */ |
| *proflen = 0; |
| |
| if (png_ptr == NULL) |
| { |
| fprintf(stderr, "iccfrompng: version library mismatch?\n"); |
| return 0; |
| } |
| |
| if (setjmp(png_jmpbuf(png_ptr))) |
| { |
| png_destroy_read_struct(&png_ptr, &info_ptr, NULL); |
| return 0; |
| } |
| |
| png_init_io(png_ptr, fp); |
| |
| info_ptr = png_create_info_struct(png_ptr); |
| if (info_ptr == NULL) |
| png_error(png_ptr, "OOM allocating info structure"); |
| |
| png_read_info(png_ptr, info_ptr); |
| |
| { |
| png_charp name; |
| int compression_type; |
| png_bytep profile; |
| |
| if (png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, &profile, |
| proflen) & PNG_INFO_iCCP) |
| { |
| result = malloc(*proflen); |
| if (result != NULL) |
| memcpy(result, profile, *proflen); |
| |
| else |
| png_error(png_ptr, "OOM allocating profile buffer"); |
| } |
| |
| else |
| result = no_profile; |
| } |
| |
| png_destroy_read_struct(&png_ptr, &info_ptr, NULL); |
| return result; |
| } |
| |
| static int |
| extract_one_file(const char *filename) |
| { |
| int result = 0; |
| FILE *fp = fopen(filename, "rb"); |
| |
| if (fp != NULL) |
| { |
| png_uint_32 proflen = 0; |
| png_bytep profile = extract(fp, &proflen); |
| |
| if (profile != NULL && profile != no_profile) |
| { |
| size_t len; |
| char *output; |
| |
| { |
| const char *ep = strrchr(filename, '.'); |
| |
| if (ep != NULL) |
| len = ep-filename; |
| |
| else |
| len = strlen(filename); |
| } |
| |
| output = malloc(len + 5); |
| if (output != NULL) |
| { |
| FILE *of; |
| |
| memcpy(output, filename, len); |
| strcpy(output+len, ".icc"); |
| |
| of = fopen(output, "wb"); |
| if (of != NULL) |
| { |
| if (fwrite(profile, proflen, 1, of) == 1 && |
| fflush(of) == 0 && |
| fclose(of) == 0) |
| { |
| if (verbose) |
| printf("%s -> %s\n", filename, output); |
| /* Success return */ |
| result = 1; |
| } |
| |
| else |
| { |
| fprintf(stderr, "%s: error writing profile\n", output); |
| if (remove(output)) |
| fprintf(stderr, "%s: could not remove file\n", output); |
| } |
| } |
| |
| else |
| fprintf(stderr, "%s: failed to open output file\n", output); |
| |
| free(output); |
| } |
| |
| else |
| fprintf(stderr, "%s: OOM allocating string!\n", filename); |
| |
| free(profile); |
| } |
| |
| else if (verbose && profile == no_profile) |
| printf("%s has no profile\n", filename); |
| } |
| |
| else |
| fprintf(stderr, "%s: could not open file\n", filename); |
| |
| return result; |
| } |
| |
| int |
| main(int argc, char **argv) |
| { |
| int i; |
| int extracted = 0; |
| |
| for (i=1; i<argc; ++i) |
| { |
| if (strcmp(argv[i], "-q") == 0) |
| verbose = 0; |
| |
| else if (extract_one_file(argv[i])) |
| extracted = 1; |
| } |
| |
| /* Exit code is true if any extract succeeds */ |
| return extracted == 0; |
| } |
| #endif /* READ && STDIO && iCCP */ |