/* feh_png.c Copyright (C) 2004 Tom Gilbert. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies of the Software and its documentation and acknowledgment shall be given in the documentation and software packages that this Software was used. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include "feh_png.h" #include <png.h> #include <stdio.h> #include <stdarg.h> #define FEH_PNG_COMPRESSION 3 #define FEH_PNG_NUM_COMMENTS 4 gib_hash *feh_png_read_comments(char *file) { gib_hash *hash = NULL; FILE *fp; int i, sig_bytes, comments = 0; png_structp png_ptr; png_infop info_ptr; png_textp text_ptr; if (!(fp = fopen(file, "rb"))) return hash; if (!(sig_bytes = feh_png_file_is_png(fp))) { fclose(fp); return hash; } /* initialize data structures */ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); if (!png_ptr) { fclose(fp); return hash; } info_ptr = png_create_info_struct(png_ptr); if (!info_ptr) { png_destroy_read_struct(&png_ptr, (png_infopp) NULL, (png_infopp) NULL); fclose(fp); return hash; } if (setjmp(png_jmpbuf(png_ptr))) { png_destroy_read_struct(&png_ptr, &info_ptr, NULL); fclose(fp); return hash; } /* initialize reading */ png_init_io(png_ptr, fp); png_set_sig_bytes(png_ptr, sig_bytes); png_read_info(png_ptr, info_ptr); #ifdef PNG_TEXT_SUPPORTED png_get_text(png_ptr, info_ptr, &text_ptr, &comments); if (comments > 0) { hash = gib_hash_new(); for (i = 0; i < comments; i++) gib_hash_set(hash, text_ptr[i].key, estrdup(text_ptr[i].text)); } #endif /* PNG_TEXT_SUPPORTED */ png_destroy_read_struct(&png_ptr, &info_ptr, NULL); fclose(fp); return hash; } /* grab image data from image and write info file with comments ... */ int feh_png_write_png(Imlib_Image image, char *file, ...) { FILE *fp; int i, w, h; png_structp png_ptr; png_infop info_ptr; png_color_8 sig_bit; DATA32 *ptr; #ifdef PNG_TEXT_SUPPORTED va_list args; png_text text[FEH_PNG_NUM_COMMENTS]; char *pair_key, *pair_text; #endif /* PNG_TEXT_SUPPORTED */ if (!(fp = fopen(file, "wb"))) return 0; png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); if (!png_ptr) { fclose(fp); return 0; } info_ptr = png_create_info_struct(png_ptr); if (!info_ptr) { png_destroy_write_struct(&png_ptr, (png_infopp) NULL); fclose(fp); return 0; } if (setjmp(png_jmpbuf(png_ptr))) { fclose(fp); png_destroy_write_struct(&png_ptr, &info_ptr); png_destroy_info_struct(png_ptr, &info_ptr); return 0; } w = gib_imlib_image_get_width(image); h = gib_imlib_image_get_height(image); png_init_io(png_ptr, fp); png_set_IHDR(png_ptr, info_ptr, w, h, 8, PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); #ifdef WORDS_BIGENDIAN png_set_swap_alpha(png_ptr); #else /* !WORDS_BIGENDIAN */ png_set_bgr(png_ptr); #endif /* WORDS_BIGENDIAN */ sig_bit.red = 8; sig_bit.green = 8; sig_bit.blue = 8; sig_bit.alpha = 8; png_set_sBIT(png_ptr, info_ptr, &sig_bit); #ifdef PNG_TEXT_SUPPORTED va_start(args, file); for (i = 0; i < FEH_PNG_NUM_COMMENTS; i++) { if ((pair_key = va_arg(args, char *)) && (pair_text = va_arg(args, char *))) { /* got a complete pair, add to info structure */ text[i].key = pair_key; text[i].text = pair_text; text[i].compression = PNG_TEXT_COMPRESSION_NONE; } else break; } va_end(args); if (i > 0) png_set_text(png_ptr, info_ptr, text, i); #endif /* PNG_TEXT_SUPPORTED */ png_set_compression_level(png_ptr, FEH_PNG_COMPRESSION); png_write_info(png_ptr, info_ptr); png_set_shift(png_ptr, &sig_bit); png_set_packing(png_ptr); /* write image data */ imlib_context_set_image(image); ptr = imlib_image_get_data(); for (i = 0; i < h; i++, ptr += w) png_write_row(png_ptr, (png_bytep) ptr); png_write_end(png_ptr, info_ptr); png_destroy_write_struct(&png_ptr, &info_ptr); png_destroy_info_struct(png_ptr, &info_ptr); fclose(fp); return 0; } /* check PNG signature */ int feh_png_file_is_png(FILE * fp) { unsigned char buf[8]; fread(buf, 1, 8, fp); if (png_sig_cmp(buf, 0, 8)) { return 0; } return 8; }