X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=gtkmm-osx%2Flibpng-1.2.5%2Fcontrib%2Fgregbook%2Fwritepng.c;fp=gtkmm-osx%2Flibpng-1.2.5%2Fcontrib%2Fgregbook%2Fwritepng.c;h=6802b12fb0322b8d86e76f4402ea299f023fcaf5;hb=a095981e18cc37a8ecc7cd237cc22b9c10329264;hp=0000000000000000000000000000000000000000;hpb=9459638ad6797b8139f1e9f0715c96076dbf0890;p=synfig.git diff --git a/gtkmm-osx/libpng-1.2.5/contrib/gregbook/writepng.c b/gtkmm-osx/libpng-1.2.5/contrib/gregbook/writepng.c new file mode 100644 index 0000000..6802b12 --- /dev/null +++ b/gtkmm-osx/libpng-1.2.5/contrib/gregbook/writepng.c @@ -0,0 +1,368 @@ +/*--------------------------------------------------------------------------- + + wpng - simple PNG-writing program writepng.c + + --------------------------------------------------------------------------- + + Copyright (c) 1998-2000 Greg Roelofs. All rights reserved. + + This software is provided "as is," without warranty of any kind, + express or implied. In no event shall the author or contributors + be held liable for any damages arising in any way from the use of + this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute + it freely, subject to the following restrictions: + + 1. Redistributions of source code must retain the above copyright + notice, disclaimer, and this list of conditions. + 2. Redistributions in binary form must reproduce the above copyright + notice, disclaimer, and this list of conditions in the documenta- + tion and/or other materials provided with the distribution. + 3. All advertising materials mentioning features or use of this + software must display the following acknowledgment: + + This product includes software developed by Greg Roelofs + and contributors for the book, "PNG: The Definitive Guide," + published by O'Reilly and Associates. + + ---------------------------------------------------------------------------*/ + + +#include /* for exit() prototype */ + +#include "png.h" /* libpng header; includes zlib.h and setjmp.h */ +#include "writepng.h" /* typedefs, common macros, public prototypes */ + + +/* local prototype */ + +static void writepng_error_handler(png_structp png_ptr, png_const_charp msg); + + + +void writepng_version_info(void) +{ + fprintf(stderr, " Compiled with libpng %s; using libpng %s.\n", + PNG_LIBPNG_VER_STRING, png_libpng_ver); + fprintf(stderr, " Compiled with zlib %s; using zlib %s.\n", + ZLIB_VERSION, zlib_version); +} + + + + +/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for + * unexpected pnmtype; note that outfile might be stdout */ + +int writepng_init(mainprog_info *mainprog_ptr) +{ + png_structp png_ptr; /* note: temporary variables! */ + png_infop info_ptr; + int color_type, interlace_type; + + + /* could also replace libpng warning-handler (final NULL), but no need: */ + + png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr, + writepng_error_handler, NULL); + if (!png_ptr) + return 4; /* out of memory */ + + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) { + png_destroy_write_struct(&png_ptr, NULL); + return 4; /* out of memory */ + } + + + /* setjmp() must be called in every function that calls a PNG-writing + * libpng function, unless an alternate error handler was installed-- + * but compatible error handlers must either use longjmp() themselves + * (as in this program) or exit immediately, so here we go: */ + + if (setjmp(mainprog_ptr->jmpbuf)) { + png_destroy_write_struct(&png_ptr, &info_ptr); + return 2; + } + + + /* make sure outfile is (re)opened in BINARY mode */ + + png_init_io(png_ptr, mainprog_ptr->outfile); + + + /* set the compression levels--in general, always want to leave filtering + * turned on (except for palette images) and allow all of the filters, + * which is the default; want 32K zlib window, unless entire image buffer + * is 16K or smaller (unknown here)--also the default; usually want max + * compression (NOT the default); and remaining compression flags should + * be left alone */ + + png_set_compression_level(png_ptr, Z_BEST_COMPRESSION); +/* + >> this is default for no filtering; Z_FILTERED is default otherwise: + png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY); + >> these are all defaults: + png_set_compression_mem_level(png_ptr, 8); + png_set_compression_window_bits(png_ptr, 15); + png_set_compression_method(png_ptr, 8); + */ + + + /* set the image parameters appropriately */ + + if (mainprog_ptr->pnmtype == 5) + color_type = PNG_COLOR_TYPE_GRAY; + else if (mainprog_ptr->pnmtype == 6) + color_type = PNG_COLOR_TYPE_RGB; + else if (mainprog_ptr->pnmtype == 8) + color_type = PNG_COLOR_TYPE_RGB_ALPHA; + else { + png_destroy_write_struct(&png_ptr, &info_ptr); + return 11; + } + + interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 : + PNG_INTERLACE_NONE; + + png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height, + mainprog_ptr->sample_depth, color_type, interlace_type, + PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); + + if (mainprog_ptr->gamma > 0.0) + png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma); + + if (mainprog_ptr->have_bg) { /* we know it's RGBA, not gray+alpha */ + png_color_16 background; + + background.red = mainprog_ptr->bg_red; + background.green = mainprog_ptr->bg_green; + background.blue = mainprog_ptr->bg_blue; + png_set_bKGD(png_ptr, info_ptr, &background); + } + + if (mainprog_ptr->have_time) { + png_time modtime; + + png_convert_from_time_t(&modtime, mainprog_ptr->modtime); + png_set_tIME(png_ptr, info_ptr, &modtime); + } + + if (mainprog_ptr->have_text) { + png_text text[6]; + int num_text = 0; + + if (mainprog_ptr->have_text & TEXT_TITLE) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "Title"; + text[num_text].text = mainprog_ptr->title; + ++num_text; + } + if (mainprog_ptr->have_text & TEXT_AUTHOR) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "Author"; + text[num_text].text = mainprog_ptr->author; + ++num_text; + } + if (mainprog_ptr->have_text & TEXT_DESC) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "Description"; + text[num_text].text = mainprog_ptr->desc; + ++num_text; + } + if (mainprog_ptr->have_text & TEXT_COPY) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "Copyright"; + text[num_text].text = mainprog_ptr->copyright; + ++num_text; + } + if (mainprog_ptr->have_text & TEXT_EMAIL) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "E-mail"; + text[num_text].text = mainprog_ptr->email; + ++num_text; + } + if (mainprog_ptr->have_text & TEXT_URL) { + text[num_text].compression = PNG_TEXT_COMPRESSION_NONE; + text[num_text].key = "URL"; + text[num_text].text = mainprog_ptr->url; + ++num_text; + } + png_set_text(png_ptr, info_ptr, text, num_text); + } + + + /* write all chunks up to (but not including) first IDAT */ + + png_write_info(png_ptr, info_ptr); + + + /* if we wanted to write any more text info *after* the image data, we + * would set up text struct(s) here and call png_set_text() again, with + * just the new data; png_set_tIME() could also go here, but it would + * have no effect since we already called it above (only one tIME chunk + * allowed) */ + + + /* set up the transformations: for now, just pack low-bit-depth pixels + * into bytes (one, two or four pixels per byte) */ + + png_set_packing(png_ptr); +/* png_set_shift(png_ptr, &sig_bit); to scale low-bit-depth values */ + + + /* make sure we save our pointers for use in writepng_encode_image() */ + + mainprog_ptr->png_ptr = png_ptr; + mainprog_ptr->info_ptr = info_ptr; + + + /* OK, that's all we need to do for now; return happy */ + + return 0; +} + + + + + +/* returns 0 for success, 2 for libpng (longjmp) problem */ + +int writepng_encode_image(mainprog_info *mainprog_ptr) +{ + png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr; + png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr; + + + /* as always, setjmp() must be called in every function that calls a + * PNG-writing libpng function */ + + if (setjmp(mainprog_ptr->jmpbuf)) { + png_destroy_write_struct(&png_ptr, &info_ptr); + mainprog_ptr->png_ptr = NULL; + mainprog_ptr->info_ptr = NULL; + return 2; + } + + + /* and now we just write the whole image; libpng takes care of interlacing + * for us */ + + png_write_image(png_ptr, mainprog_ptr->row_pointers); + + + /* since that's it, we also close out the end of the PNG file now--if we + * had any text or time info to write after the IDATs, second argument + * would be info_ptr, but we optimize slightly by sending NULL pointer: */ + + png_write_end(png_ptr, NULL); + + return 0; +} + + + + + +/* returns 0 if succeeds, 2 if libpng problem */ + +int writepng_encode_row(mainprog_info *mainprog_ptr) /* NON-interlaced only! */ +{ + png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr; + png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr; + + + /* as always, setjmp() must be called in every function that calls a + * PNG-writing libpng function */ + + if (setjmp(mainprog_ptr->jmpbuf)) { + png_destroy_write_struct(&png_ptr, &info_ptr); + mainprog_ptr->png_ptr = NULL; + mainprog_ptr->info_ptr = NULL; + return 2; + } + + + /* image_data points at our one row of image data */ + + png_write_row(png_ptr, mainprog_ptr->image_data); + + return 0; +} + + + + + +/* returns 0 if succeeds, 2 if libpng problem */ + +int writepng_encode_finish(mainprog_info *mainprog_ptr) /* NON-interlaced! */ +{ + png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr; + png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr; + + + /* as always, setjmp() must be called in every function that calls a + * PNG-writing libpng function */ + + if (setjmp(mainprog_ptr->jmpbuf)) { + png_destroy_write_struct(&png_ptr, &info_ptr); + mainprog_ptr->png_ptr = NULL; + mainprog_ptr->info_ptr = NULL; + return 2; + } + + + /* close out PNG file; if we had any text or time info to write after + * the IDATs, second argument would be info_ptr: */ + + png_write_end(png_ptr, NULL); + + return 0; +} + + + + + +void writepng_cleanup(mainprog_info *mainprog_ptr) +{ + png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr; + png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr; + + if (png_ptr && info_ptr) + png_destroy_write_struct(&png_ptr, &info_ptr); +} + + + + + +static void writepng_error_handler(png_structp png_ptr, png_const_charp msg) +{ + mainprog_info *mainprog_ptr; + + /* This function, aside from the extra step of retrieving the "error + * pointer" (below) and the fact that it exists within the application + * rather than within libpng, is essentially identical to libpng's + * default error handler. The second point is critical: since both + * setjmp() and longjmp() are called from the same code, they are + * guaranteed to have compatible notions of how big a jmp_buf is, + * regardless of whether _BSD_SOURCE or anything else has (or has not) + * been defined. */ + + fprintf(stderr, "writepng libpng error: %s\n", msg); + fflush(stderr); + + mainprog_ptr = png_get_error_ptr(png_ptr); + if (mainprog_ptr == NULL) { /* we are completely hosed now */ + fprintf(stderr, + "writepng severe error: jmpbuf not recoverable; terminating.\n"); + fflush(stderr); + exit(99); + } + + longjmp(mainprog_ptr->jmpbuf, 1); +}