diff options
Diffstat (limited to 'src/3rdparty/libpng/pngwrite.c')
| -rw-r--r-- | src/3rdparty/libpng/pngwrite.c | 1605 |
1 files changed, 1605 insertions, 0 deletions
diff --git a/src/3rdparty/libpng/pngwrite.c b/src/3rdparty/libpng/pngwrite.c new file mode 100644 index 0000000..d90f449 --- /dev/null +++ b/src/3rdparty/libpng/pngwrite.c @@ -0,0 +1,1605 @@ + +/* pngwrite.c - general routines to write a PNG file + * + * Last changed in libpng 1.5.1 [February 3, 2011] + * Copyright (c) 1998-2011 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#include "pngpriv.h" + +#ifdef PNG_WRITE_SUPPORTED + +/* Writes all the PNG information. This is the suggested way to use the + * library. If you have a new chunk to add, make a function to write it, + * and put it in the correct location here. If you want the chunk written + * after the image data, put it in png_write_end(). I strongly encourage + * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing + * the chunk, as that will keep the code from breaking if you want to just + * write a plain PNG file. If you have long comments, I suggest writing + * them in png_write_end(), and compressing them. + */ +void PNGAPI +png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_write_info_before_PLTE"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE)) + { + /* Write PNG signature */ + png_write_sig(png_ptr); + +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \ + (png_ptr->mng_features_permitted)) + { + png_warning(png_ptr, "MNG features are not allowed in a PNG datastream"); + png_ptr->mng_features_permitted = 0; + } +#endif + + /* Write IHDR information. */ + png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height, + info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type, + info_ptr->filter_type, +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + info_ptr->interlace_type); +#else + 0); +#endif + /* The rest of these check to see if the valid field has the appropriate + * flag set, and if it does, writes the chunk. + */ +#ifdef PNG_WRITE_gAMA_SUPPORTED + if (info_ptr->valid & PNG_INFO_gAMA) + png_write_gAMA_fixed(png_ptr, info_ptr->gamma); +#endif +#ifdef PNG_WRITE_sRGB_SUPPORTED + if (info_ptr->valid & PNG_INFO_sRGB) + png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent); +#endif + +#ifdef PNG_WRITE_iCCP_SUPPORTED + if (info_ptr->valid & PNG_INFO_iCCP) + png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE, + (png_charp)info_ptr->iccp_profile, (int)info_ptr->iccp_proflen); +#endif +#ifdef PNG_WRITE_sBIT_SUPPORTED + if (info_ptr->valid & PNG_INFO_sBIT) + png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type); +#endif +#ifdef PNG_WRITE_cHRM_SUPPORTED + if (info_ptr->valid & PNG_INFO_cHRM) + png_write_cHRM_fixed(png_ptr, + info_ptr->x_white, info_ptr->y_white, + info_ptr->x_red, info_ptr->y_red, + info_ptr->x_green, info_ptr->y_green, + info_ptr->x_blue, info_ptr->y_blue); +#endif + +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && !(up->location & PNG_HAVE_PLTE) && + !(up->location & PNG_HAVE_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + if (up->size == 0) + png_warning(png_ptr, "Writing zero-length unknown chunk"); + + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif + png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE; + } +} + +void PNGAPI +png_write_info(png_structp png_ptr, png_infop info_ptr) +{ +#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) + int i; +#endif + + png_debug(1, "in png_write_info"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_write_info_before_PLTE(png_ptr, info_ptr); + + if (info_ptr->valid & PNG_INFO_PLTE) + png_write_PLTE(png_ptr, info_ptr->palette, + (png_uint_32)info_ptr->num_palette); + + else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + png_error(png_ptr, "Valid palette required for paletted images"); + +#ifdef PNG_WRITE_tRNS_SUPPORTED + if (info_ptr->valid & PNG_INFO_tRNS) + { +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel (in tRNS) */ + if ((png_ptr->transformations & PNG_INVERT_ALPHA) && + info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + int j; + for (j = 0; j<(int)info_ptr->num_trans; j++) + info_ptr->trans_alpha[j] = + (png_byte)(255 - info_ptr->trans_alpha[j]); + } +#endif + png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color), + info_ptr->num_trans, info_ptr->color_type); + } +#endif +#ifdef PNG_WRITE_bKGD_SUPPORTED + if (info_ptr->valid & PNG_INFO_bKGD) + png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type); +#endif + +#ifdef PNG_WRITE_hIST_SUPPORTED + if (info_ptr->valid & PNG_INFO_hIST) + png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette); +#endif + +#ifdef PNG_WRITE_oFFs_SUPPORTED + if (info_ptr->valid & PNG_INFO_oFFs) + png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset, + info_ptr->offset_unit_type); +#endif + +#ifdef PNG_WRITE_pCAL_SUPPORTED + if (info_ptr->valid & PNG_INFO_pCAL) + png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0, + info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams, + info_ptr->pcal_units, info_ptr->pcal_params); +#endif + +#ifdef PNG_WRITE_sCAL_SUPPORTED + if (info_ptr->valid & PNG_INFO_sCAL) + png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit, + info_ptr->scal_s_width, info_ptr->scal_s_height); +#endif /* sCAL */ + +#ifdef PNG_WRITE_pHYs_SUPPORTED + if (info_ptr->valid & PNG_INFO_pHYs) + png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit, + info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type); +#endif /* pHYs */ + +#ifdef PNG_WRITE_tIME_SUPPORTED + if (info_ptr->valid & PNG_INFO_tIME) + { + png_write_tIME(png_ptr, &(info_ptr->mod_time)); + png_ptr->mode |= PNG_WROTE_tIME; + } +#endif /* tIME */ + +#ifdef PNG_WRITE_sPLT_SUPPORTED + if (info_ptr->valid & PNG_INFO_sPLT) + for (i = 0; i < (int)info_ptr->splt_palettes_num; i++) + png_write_sPLT(png_ptr, info_ptr->splt_palettes + i); +#endif /* sPLT */ + +#ifdef PNG_WRITE_TEXT_SUPPORTED + /* Check to see if we need to write text chunks */ + for (i = 0; i < info_ptr->num_text; i++) + { + png_debug2(2, "Writing header text chunk %d, type %d", i, + info_ptr->text[i].compression); + /* An internationalized chunk? */ + if (info_ptr->text[i].compression > 0) + { +#ifdef PNG_WRITE_iTXt_SUPPORTED + /* Write international chunk */ + png_write_iTXt(png_ptr, + info_ptr->text[i].compression, + info_ptr->text[i].key, + info_ptr->text[i].lang, + info_ptr->text[i].lang_key, + info_ptr->text[i].text); +#else + png_warning(png_ptr, "Unable to write international text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + + /* If we want a compressed text chunk */ + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt) + { +#ifdef PNG_WRITE_zTXt_SUPPORTED + /* Write compressed chunk */ + png_write_zTXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0, + info_ptr->text[i].compression); +#else + png_warning(png_ptr, "Unable to write compressed text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; + } + + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) + { +#ifdef PNG_WRITE_tEXt_SUPPORTED + /* Write uncompressed chunk */ + png_write_tEXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, + 0); + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; +#else + /* Can't get here */ + png_warning(png_ptr, "Unable to write uncompressed text"); +#endif + } + } +#endif /* tEXt */ + +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && (up->location & PNG_HAVE_PLTE) && + !(up->location & PNG_HAVE_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif +} + +/* Writes the end of the PNG file. If you don't want to write comments or + * time information, you can pass NULL for info. If you already wrote these + * in png_write_info(), do not write them again here. If you have long + * comments, I suggest writing them here, and compressing them. + */ +void PNGAPI +png_write_end(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_write_end"); + + if (png_ptr == NULL) + return; + + if (!(png_ptr->mode & PNG_HAVE_IDAT)) + png_error(png_ptr, "No IDATs written into file"); + + /* See if user wants us to write information chunks */ + if (info_ptr != NULL) + { +#ifdef PNG_WRITE_TEXT_SUPPORTED + int i; /* local index variable */ +#endif +#ifdef PNG_WRITE_tIME_SUPPORTED + /* Check to see if user has supplied a time chunk */ + if ((info_ptr->valid & PNG_INFO_tIME) && + !(png_ptr->mode & PNG_WROTE_tIME)) + png_write_tIME(png_ptr, &(info_ptr->mod_time)); + +#endif +#ifdef PNG_WRITE_TEXT_SUPPORTED + /* Loop through comment chunks */ + for (i = 0; i < info_ptr->num_text; i++) + { + png_debug2(2, "Writing trailer text chunk %d, type %d", i, + info_ptr->text[i].compression); + /* An internationalized chunk? */ + if (info_ptr->text[i].compression > 0) + { +#ifdef PNG_WRITE_iTXt_SUPPORTED + /* Write international chunk */ + png_write_iTXt(png_ptr, + info_ptr->text[i].compression, + info_ptr->text[i].key, + info_ptr->text[i].lang, + info_ptr->text[i].lang_key, + info_ptr->text[i].text); +#else + png_warning(png_ptr, "Unable to write international text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + + else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt) + { +#ifdef PNG_WRITE_zTXt_SUPPORTED + /* Write compressed chunk */ + png_write_zTXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0, + info_ptr->text[i].compression); +#else + png_warning(png_ptr, "Unable to write compressed text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; + } + + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) + { +#ifdef PNG_WRITE_tEXt_SUPPORTED + /* Write uncompressed chunk */ + png_write_tEXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0); +#else + png_warning(png_ptr, "Unable to write uncompressed text"); +#endif + + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + } +#endif +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && (up->location & PNG_AFTER_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif + } + + png_ptr->mode |= PNG_AFTER_IDAT; + + /* Write end of PNG file */ + png_write_IEND(png_ptr); + /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03, + * and restored again in libpng-1.2.30, may cause some applications that + * do not set png_ptr->output_flush_fn to crash. If your application + * experiences a problem, please try building libpng with + * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to + * png-mng-implement at lists.sf.net . + */ +#ifdef PNG_WRITE_FLUSH_SUPPORTED +# ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED + png_flush(png_ptr); +# endif +#endif +} + +#ifdef PNG_CONVERT_tIME_SUPPORTED +/* "tm" structure is not supported on WindowsCE */ +void PNGAPI +png_convert_from_struct_tm(png_timep ptime, PNG_CONST struct tm FAR * ttime) +{ + png_debug(1, "in png_convert_from_struct_tm"); + + ptime->year = (png_uint_16)(1900 + ttime->tm_year); + ptime->month = (png_byte)(ttime->tm_mon + 1); + ptime->day = (png_byte)ttime->tm_mday; + ptime->hour = (png_byte)ttime->tm_hour; + ptime->minute = (png_byte)ttime->tm_min; + ptime->second = (png_byte)ttime->tm_sec; +} + +void PNGAPI +png_convert_from_time_t(png_timep ptime, time_t ttime) +{ + struct tm *tbuf; + + png_debug(1, "in png_convert_from_time_t"); + + tbuf = gmtime(&ttime); + png_convert_from_struct_tm(ptime, tbuf); +} +#endif + +/* Initialize png_ptr structure, and allocate any memory needed */ +PNG_FUNCTION(png_structp,PNGAPI +png_create_write_struct,(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn, + warn_fn, NULL, NULL, NULL)); +} + +/* Alternate initialize png_ptr structure, and allocate any memory needed */ +static void png_reset_filter_heuristics(png_structp png_ptr); /* forward decl */ + +PNG_FUNCTION(png_structp,PNGAPI +png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + volatile int png_cleanup_needed = 0; +#ifdef PNG_SETJMP_SUPPORTED + volatile +#endif + png_structp png_ptr; +#ifdef PNG_SETJMP_SUPPORTED +#ifdef USE_FAR_KEYWORD + jmp_buf png_jmpbuf; +#endif +#endif + int i; + + png_debug(1, "in png_create_write_struct"); + +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, + (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); +#else + png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); +#endif /* PNG_USER_MEM_SUPPORTED */ + if (png_ptr == NULL) + return (NULL); + + /* Added at libpng-1.2.6 */ +#ifdef PNG_SET_USER_LIMITS_SUPPORTED + png_ptr->user_width_max = PNG_USER_WIDTH_MAX; + png_ptr->user_height_max = PNG_USER_HEIGHT_MAX; +#endif + +#ifdef PNG_SETJMP_SUPPORTED +/* Applications that neglect to set up their own setjmp() and then + encounter a png_error() will longjmp here. Since the jmpbuf is + then meaningless we abort instead of returning. */ +#ifdef USE_FAR_KEYWORD + if (setjmp(png_jmpbuf)) +#else + if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */ +#endif +#ifdef USE_FAR_KEYWORD + png_memcpy(png_jmpbuf(png_ptr), png_jmpbuf, png_sizeof(jmp_buf)); +#endif + PNG_ABORT(); +#endif + +#ifdef PNG_USER_MEM_SUPPORTED + png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); +#endif /* PNG_USER_MEM_SUPPORTED */ + png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); + + if (user_png_ver) + { + i = 0; + do + { + if (user_png_ver[i] != png_libpng_ver[i]) + png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; + } while (png_libpng_ver[i++]); + } + + if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) + { + /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so + * we must recompile any applications that use any older library version. + * For versions after libpng 1.0, we will be compatible, so we need + * only check the first digit. + */ + if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || + (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || + (user_png_ver[0] == '0' && user_png_ver[2] < '9')) + { +#ifdef PNG_CONSOLE_IO_SUPPORTED + char msg[80]; + + if (user_png_ver) + { + png_snprintf2(msg, 80, + "Application built with libpng-%.20s" + " but running with %.20s", + user_png_ver, + png_libpng_ver); + png_warning(png_ptr, msg); + } +#else + png_warning(png_ptr, + "Incompatible libpng version in application and library"); +#endif +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + png_ptr->flags = 0; +#endif + png_cleanup_needed = 1; + } + } + + /* Initialize zbuf - compression buffer */ + png_ptr->zbuf_size = PNG_ZBUF_SIZE; + + if (!png_cleanup_needed) + { + png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr, + png_ptr->zbuf_size); + if (png_ptr->zbuf == NULL) + png_cleanup_needed = 1; + } + + if (png_cleanup_needed) + { + /* Clean up PNG structure and deallocate any memory. */ + png_free(png_ptr, png_ptr->zbuf); + png_ptr->zbuf = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, + (png_free_ptr)free_fn, (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + return (NULL); + } + + png_set_write_fn(png_ptr, NULL, NULL, NULL); + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + png_reset_filter_heuristics(png_ptr); +#endif + + return (png_ptr); +} + + +/* Write a few rows of image data. If the image is interlaced, + * either you will have to write the 7 sub images, or, if you + * have called png_set_interlace_handling(), you will have to + * "write" the image seven times. + */ +void PNGAPI +png_write_rows(png_structp png_ptr, png_bytepp row, + png_uint_32 num_rows) +{ + png_uint_32 i; /* row counter */ + png_bytepp rp; /* row pointer */ + + png_debug(1, "in png_write_rows"); + + if (png_ptr == NULL) + return; + + /* Loop through the rows */ + for (i = 0, rp = row; i < num_rows; i++, rp++) + { + png_write_row(png_ptr, *rp); + } +} + +/* Write the image. You only need to call this function once, even + * if you are writing an interlaced image. + */ +void PNGAPI +png_write_image(png_structp png_ptr, png_bytepp image) +{ + png_uint_32 i; /* row index */ + int pass, num_pass; /* pass variables */ + png_bytepp rp; /* points to current row */ + + if (png_ptr == NULL) + return; + + png_debug(1, "in png_write_image"); + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Initialize interlace handling. If image is not interlaced, + * this will set pass to 1 + */ + num_pass = png_set_interlace_handling(png_ptr); +#else + num_pass = 1; +#endif + /* Loop through passes */ + for (pass = 0; pass < num_pass; pass++) + { + /* Loop through image */ + for (i = 0, rp = image; i < png_ptr->height; i++, rp++) + { + png_write_row(png_ptr, *rp); + } + } +} + +/* Called by user to write a row of image data */ +void PNGAPI +png_write_row(png_structp png_ptr, png_const_bytep row) +{ + if (png_ptr == NULL) + return; + + png_debug2(1, "in png_write_row (row %u, pass %d)", + png_ptr->row_number, png_ptr->pass); + + /* Initialize transformations and other stuff if first time */ + if (png_ptr->row_number == 0 && png_ptr->pass == 0) + { + /* Make sure we wrote the header info */ + if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE)) + png_error(png_ptr, + "png_write_info was never called before png_write_row"); + + /* Check for transforms that have been set but were defined out */ +#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED) + if (png_ptr->transformations & PNG_INVERT_MONO) + png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined"); +#endif + +#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED) + if (png_ptr->transformations & PNG_FILLER) + png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \ + defined(PNG_READ_PACKSWAP_SUPPORTED) + if (png_ptr->transformations & PNG_PACKSWAP) + png_warning(png_ptr, + "PNG_WRITE_PACKSWAP_SUPPORTED is not defined"); +#endif + +#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED) + if (png_ptr->transformations & PNG_PACK) + png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined"); +#endif + +#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED) + if (png_ptr->transformations & PNG_SHIFT) + png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined"); +#endif + +#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED) + if (png_ptr->transformations & PNG_BGR) + png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined"); +#endif + +#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED) + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined"); +#endif + + png_write_start_row(png_ptr); + } + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* If interlaced and not interested in row, return */ + if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) + { + switch (png_ptr->pass) + { + case 0: + if (png_ptr->row_number & 0x07) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 1: + if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 2: + if ((png_ptr->row_number & 0x07) != 4) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 3: + if ((png_ptr->row_number & 0x03) || png_ptr->width < 3) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 4: + if ((png_ptr->row_number & 0x03) != 2) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 5: + if ((png_ptr->row_number & 0x01) || png_ptr->width < 2) + { + png_write_finish_row(png_ptr); + return; + } + break; + + case 6: + if (!(png_ptr->row_number & 0x01)) + { + png_write_finish_row(png_ptr); + return; + } + break; + + default: /* error: ignore it */ + break; + } + } +#endif + + /* Set up row info for transformations */ + png_ptr->row_info.color_type = png_ptr->color_type; + png_ptr->row_info.width = png_ptr->usr_width; + png_ptr->row_info.channels = png_ptr->usr_channels; + png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth; + png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth * + png_ptr->row_info.channels); + + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + + png_debug1(3, "row_info->color_type = %d", png_ptr->row_info.color_type); + png_debug1(3, "row_info->width = %u", png_ptr->row_info.width); + png_debug1(3, "row_info->channels = %d", png_ptr->row_info.channels); + png_debug1(3, "row_info->bit_depth = %d", png_ptr->row_info.bit_depth); + png_debug1(3, "row_info->pixel_depth = %d", png_ptr->row_info.pixel_depth); + png_debug1(3, "row_info->rowbytes = %lu", + (unsigned long)png_ptr->row_info.rowbytes); + + /* Copy user's row into buffer, leaving room for filter byte. */ + png_memcpy(png_ptr->row_buf + 1, row, png_ptr->row_info.rowbytes); + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Handle interlacing */ + if (png_ptr->interlaced && png_ptr->pass < 6 && + (png_ptr->transformations & PNG_INTERLACE)) + { + png_do_write_interlace(&(png_ptr->row_info), + png_ptr->row_buf + 1, png_ptr->pass); + /* This should always get caught above, but still ... */ + if (!(png_ptr->row_info.width)) + { + png_write_finish_row(png_ptr); + return; + } + } +#endif + + /* Handle other transformations */ + if (png_ptr->transformations) + png_do_write_transformations(png_ptr); + +#ifdef PNG_MNG_FEATURES_SUPPORTED + /* Write filter_method 64 (intrapixel differencing) only if + * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and + * 2. Libpng did not write a PNG signature (this filter_method is only + * used in PNG datastreams that are embedded in MNG datastreams) and + * 3. The application called png_permit_mng_features with a mask that + * included PNG_FLAG_MNG_FILTER_64 and + * 4. The filter_method is 64 and + * 5. The color_type is RGB or RGBA + */ + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) + { + /* Intrapixel differencing */ + png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); + } +#endif + + /* Find a filter if necessary, filter the row and write it out. */ + png_write_find_filter(png_ptr, &(png_ptr->row_info)); + + if (png_ptr->write_row_fn != NULL) + (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); +} + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +/* Set the automatic flush interval or 0 to turn flushing off */ +void PNGAPI +png_set_flush(png_structp png_ptr, int nrows) +{ + png_debug(1, "in png_set_flush"); + + if (png_ptr == NULL) + return; + + png_ptr->flush_dist = (nrows < 0 ? 0 : nrows); +} + +/* Flush the current output buffers now */ +void PNGAPI +png_write_flush(png_structp png_ptr) +{ + int wrote_IDAT; + + png_debug(1, "in png_write_flush"); + + if (png_ptr == NULL) + return; + + /* We have already written out all of the data */ + if (png_ptr->row_number >= png_ptr->num_rows) + return; + + do + { + int ret; + + /* Compress the data */ + ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH); + wrote_IDAT = 0; + + /* Check for compression errors */ + if (ret != Z_OK) + { + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + + else + png_error(png_ptr, "zlib error"); + } + + if (!(png_ptr->zstream.avail_out)) + { + /* Write the IDAT and reset the zlib output buffer */ + png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + wrote_IDAT = 1; + } + } while (wrote_IDAT == 1); + + /* If there is any data left to be output, write it into a new IDAT */ + if (png_ptr->zbuf_size != png_ptr->zstream.avail_out) + { + /* Write the IDAT and reset the zlib output buffer */ + png_write_IDAT(png_ptr, png_ptr->zbuf, + png_ptr->zbuf_size - png_ptr->zstream.avail_out); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + } + png_ptr->flush_rows = 0; + png_flush(png_ptr); +} +#endif /* PNG_WRITE_FLUSH_SUPPORTED */ + +/* Free all memory used by the write */ +void PNGAPI +png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr) +{ + png_structp png_ptr = NULL; + png_infop info_ptr = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn = NULL; + png_voidp mem_ptr = NULL; +#endif + + png_debug(1, "in png_destroy_write_struct"); + + if (png_ptr_ptr != NULL) + { + png_ptr = *png_ptr_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; +#endif + } + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr != NULL) + { + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; + } +#endif + + if (info_ptr_ptr != NULL) + info_ptr = *info_ptr_ptr; + + if (info_ptr != NULL) + { + if (png_ptr != NULL) + { + png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1); + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + if (png_ptr->num_chunk_list) + { + png_free(png_ptr, png_ptr->chunk_list); + png_ptr->num_chunk_list = 0; + } +#endif + } + +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)info_ptr); +#endif + *info_ptr_ptr = NULL; + } + + if (png_ptr != NULL) + { + png_write_destroy(png_ptr); +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + *png_ptr_ptr = NULL; + } +} + + +/* Free any memory used in png_ptr struct (old method) */ +void /* PRIVATE */ +png_write_destroy(png_structp png_ptr) +{ +#ifdef PNG_SETJMP_SUPPORTED + jmp_buf tmp_jmp; /* Save jump buffer */ +#endif + png_error_ptr error_fn; + png_error_ptr warning_fn; + png_voidp error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn; +#endif + + png_debug(1, "in png_write_destroy"); + + /* Free any memory zlib uses */ + deflateEnd(&png_ptr->zstream); + + /* Free our memory. png_free checks NULL for us. */ + png_free(png_ptr, png_ptr->zbuf); + png_free(png_ptr, png_ptr->row_buf); +#ifdef PNG_WRITE_FILTER_SUPPORTED + png_free(png_ptr, png_ptr->prev_row); + png_free(png_ptr, png_ptr->sub_row); + png_free(png_ptr, png_ptr->up_row); + png_free(png_ptr, png_ptr->avg_row); + png_free(png_ptr, png_ptr->paeth_row); +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED + png_free(png_ptr, png_ptr->time_buffer); +#endif + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + /* Use this to save a little code space, it doesn't free the filter_costs */ + png_reset_filter_heuristics(png_ptr); + png_free(png_ptr, png_ptr->filter_costs); + png_free(png_ptr, png_ptr->inv_filter_costs); +#endif + +#ifdef PNG_SETJMP_SUPPORTED + /* Reset structure */ + png_memcpy(tmp_jmp, png_ptr->png_jmpbuf, png_sizeof(jmp_buf)); +#endif + + error_fn = png_ptr->error_fn; + warning_fn = png_ptr->warning_fn; + error_ptr = png_ptr->error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; +#endif + + png_memset(png_ptr, 0, png_sizeof(png_struct)); + + png_ptr->error_fn = error_fn; + png_ptr->warning_fn = warning_fn; + png_ptr->error_ptr = error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr->free_fn = free_fn; +#endif + +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(png_ptr->png_jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); +#endif +} + +/* Allow the application to select one or more row filters to use. */ +void PNGAPI +png_set_filter(png_structp png_ptr, int method, int filters) +{ + png_debug(1, "in png_set_filter"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (method == PNG_INTRAPIXEL_DIFFERENCING)) + method = PNG_FILTER_TYPE_BASE; + +#endif + if (method == PNG_FILTER_TYPE_BASE) + { + switch (filters & (PNG_ALL_FILTERS | 0x07)) + { +#ifdef PNG_WRITE_FILTER_SUPPORTED + case 5: + case 6: + case 7: png_warning(png_ptr, "Unknown row filter for method 0"); +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + case PNG_FILTER_VALUE_NONE: + png_ptr->do_filter = PNG_FILTER_NONE; break; + +#ifdef PNG_WRITE_FILTER_SUPPORTED + case PNG_FILTER_VALUE_SUB: + png_ptr->do_filter = PNG_FILTER_SUB; break; + + case PNG_FILTER_VALUE_UP: + png_ptr->do_filter = PNG_FILTER_UP; break; + + case PNG_FILTER_VALUE_AVG: + png_ptr->do_filter = PNG_FILTER_AVG; break; + + case PNG_FILTER_VALUE_PAETH: + png_ptr->do_filter = PNG_FILTER_PAETH; break; + + default: + png_ptr->do_filter = (png_byte)filters; break; +#else + default: + png_warning(png_ptr, "Unknown row filter for method 0"); +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + } + + /* If we have allocated the row_buf, this means we have already started + * with the image and we should have allocated all of the filter buffers + * that have been selected. If prev_row isn't already allocated, then + * it is too late to start using the filters that need it, since we + * will be missing the data in the previous row. If an application + * wants to start and stop using particular filters during compression, + * it should start out with all of the filters, and then add and + * remove them after the start of compression. + */ + if (png_ptr->row_buf != NULL) + { +#ifdef PNG_WRITE_FILTER_SUPPORTED + if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL) + { + png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB; + } + + if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Up filter after starting"); + png_ptr->do_filter = (png_byte)(png_ptr->do_filter & + ~PNG_FILTER_UP); + } + + else + { + png_ptr->up_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->up_row[0] = PNG_FILTER_VALUE_UP; + } + } + + if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Average filter after starting"); + png_ptr->do_filter = (png_byte)(png_ptr->do_filter & + ~PNG_FILTER_AVG); + } + + else + { + png_ptr->avg_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG; + } + } + + if ((png_ptr->do_filter & PNG_FILTER_PAETH) && + png_ptr->paeth_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Paeth filter after starting"); + png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH); + } + + else + { + png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH; + } + } + + if (png_ptr->do_filter == PNG_NO_FILTERS) +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + png_ptr->do_filter = PNG_FILTER_NONE; + } + } + else + png_error(png_ptr, "Unknown custom filter method"); +} + +/* This allows us to influence the way in which libpng chooses the "best" + * filter for the current scanline. While the "minimum-sum-of-absolute- + * differences metric is relatively fast and effective, there is some + * question as to whether it can be improved upon by trying to keep the + * filtered data going to zlib more consistent, hopefully resulting in + * better compression. + */ +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* GRR 970116 */ +/* Conveneince reset API. */ +static void +png_reset_filter_heuristics(png_structp png_ptr) +{ + /* Clear out any old values in the 'weights' - this must be done because if + * the app calls set_filter_heuristics multiple times with different + * 'num_weights' values we would otherwise potentially have wrong sized + * arrays. + */ + png_ptr->num_prev_filters = 0; + png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED; + if (png_ptr->prev_filters != NULL) + { + png_bytep old = png_ptr->prev_filters; + png_ptr->prev_filters = NULL; + png_free(png_ptr, old); + } + if (png_ptr->filter_weights != NULL) + { + png_uint_16p old = png_ptr->filter_weights; + png_ptr->filter_weights = NULL; + png_free(png_ptr, old); + } + + if (png_ptr->inv_filter_weights != NULL) + { + png_uint_16p old = png_ptr->inv_filter_weights; + png_ptr->inv_filter_weights = NULL; + png_free(png_ptr, old); + } + + /* Leave the filter_costs - this array is fixed size. */ +} + +static int +png_init_filter_heuristics(png_structp png_ptr, int heuristic_method, + int num_weights) +{ + if (png_ptr == NULL) + return 0; + + /* Clear out the arrays */ + png_reset_filter_heuristics(png_ptr); + + /* Check arguments; the 'reset' function makes the correct settings for the + * unweighted case, but we must handle the weight case by initializing the + * arrays for the caller. + */ + if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int i; + + if (num_weights > 0) + { + png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_byte) * num_weights)); + + /* To make sure that the weighting starts out fairly */ + for (i = 0; i < num_weights; i++) + { + png_ptr->prev_filters[i] = 255; + } + + png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * num_weights)); + + png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * num_weights)); + + for (i = 0; i < num_weights; i++) + { + png_ptr->inv_filter_weights[i] = + png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR; + } + + /* Safe to set this now */ + png_ptr->num_prev_filters = (png_byte)num_weights; + } + + /* If, in the future, there are other filter methods, this would + * need to be based on png_ptr->filter. + */ + if (png_ptr->filter_costs == NULL) + { + png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST)); + + png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST)); + } + + for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) + { + png_ptr->inv_filter_costs[i] = + png_ptr->filter_costs[i] = PNG_COST_FACTOR; + } + + /* All the arrays are inited, safe to set this: */ + png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_WEIGHTED; + + /* Return the 'ok' code. */ + return 1; + } + else if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT || + heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED) + { + return 1; + } + else + { + png_warning(png_ptr, "Unknown filter heuristic method"); + return 0; + } +} + +/* Provide floating and fixed point APIs */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +void PNGAPI +png_set_filter_heuristics(png_structp png_ptr, int heuristic_method, + int num_weights, png_const_doublep filter_weights, + png_const_doublep filter_costs) +{ + png_debug(1, "in png_set_filter_heuristics"); + + /* The internal API allocates all the arrays and ensures that the elements of + * those arrays are set to the default value. + */ + if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights)) + return; + + /* If using the weighted method copy in the weights. */ + if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int i; + for (i = 0; i < num_weights; i++) + { + if (filter_weights[i] <= 0.0) + { + png_ptr->inv_filter_weights[i] = + png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR; + } + + else + { + png_ptr->inv_filter_weights[i] = + (png_uint_16)(PNG_WEIGHT_FACTOR*filter_weights[i]+.5); + + png_ptr->filter_weights[i] = + (png_uint_16)(PNG_WEIGHT_FACTOR/filter_weights[i]+.5); + } + } + + /* Here is where we set the relative costs of the different filters. We + * should take the desired compression level into account when setting + * the costs, so that Paeth, for instance, has a high relative cost at low + * compression levels, while it has a lower relative cost at higher + * compression settings. The filter types are in order of increasing + * relative cost, so it would be possible to do this with an algorithm. + */ + for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) if (filter_costs[i] >= 1.0) + { + png_ptr->inv_filter_costs[i] = + (png_uint_16)(PNG_COST_FACTOR / filter_costs[i] + .5); + + png_ptr->filter_costs[i] = + (png_uint_16)(PNG_COST_FACTOR * filter_costs[i] + .5); + } + } +} +#endif /* FLOATING_POINT */ + +#ifdef PNG_FIXED_POINT_SUPPORTED +void PNGAPI +png_set_filter_heuristics_fixed(png_structp png_ptr, int heuristic_method, + int num_weights, png_const_fixed_point_p filter_weights, + png_const_fixed_point_p filter_costs) +{ + png_debug(1, "in png_set_filter_heuristics_fixed"); + + /* The internal API allocates all the arrays and ensures that the elements of + * those arrays are set to the default value. + */ + if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights)) + return; + + /* If using the weighted method copy in the weights. */ + if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int i; + for (i = 0; i < num_weights; i++) + { + if (filter_weights[i] <= 0) + { + png_ptr->inv_filter_weights[i] = + png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR; + } + + else + { + png_ptr->inv_filter_weights[i] = (png_uint_16) + ((PNG_WEIGHT_FACTOR*filter_weights[i]+PNG_FP_HALF)/PNG_FP_1); + + png_ptr->filter_weights[i] = (png_uint_16)((PNG_WEIGHT_FACTOR* + PNG_FP_1+(filter_weights[i]/2))/filter_weights[i]); + } + } + + /* Here is where we set the relative costs of the different filters. We + * should take the desired compression level into account when setting + * the costs, so that Paeth, for instance, has a high relative cost at low + * compression levels, while it has a lower relative cost at higher + * compression settings. The filter types are in order of increasing + * relative cost, so it would be possible to do this with an algorithm. + */ + for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) + if (filter_costs[i] >= PNG_FP_1) + { + png_uint_32 tmp; + + /* Use a 32 bit unsigned temporary here because otherwise the + * intermediate value will be a 32 bit *signed* integer (ANSI rules) + * and this will get the wrong answer on division. + */ + tmp = PNG_COST_FACTOR*PNG_FP_1 + (filter_costs[i]/2); + tmp /= filter_costs[i]; + + png_ptr->inv_filter_costs[i] = (png_uint_16)tmp; + + tmp = PNG_COST_FACTOR * filter_costs[i] + PNG_FP_HALF; + tmp /= PNG_FP_1; + + png_ptr->filter_costs[i] = (png_uint_16)tmp; + } + } +} +#endif /* FIXED_POINT */ +#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ + +void PNGAPI +png_set_compression_level(png_structp png_ptr, int level) +{ + png_debug(1, "in png_set_compression_level"); + + if (png_ptr == NULL) + return; + + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL; + png_ptr->zlib_level = level; +} + +void PNGAPI +png_set_compression_mem_level(png_structp png_ptr, int mem_level) +{ + png_debug(1, "in png_set_compression_mem_level"); + + if (png_ptr == NULL) + return; + + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL; + png_ptr->zlib_mem_level = mem_level; +} + +void PNGAPI +png_set_compression_strategy(png_structp png_ptr, int strategy) +{ + png_debug(1, "in png_set_compression_strategy"); + + if (png_ptr == NULL) + return; + + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY; + png_ptr->zlib_strategy = strategy; +} + +void PNGAPI +png_set_compression_window_bits(png_structp png_ptr, int window_bits) +{ + if (png_ptr == NULL) + return; + + if (window_bits > 15) + png_warning(png_ptr, "Only compression windows <= 32k supported by PNG"); + + else if (window_bits < 8) + png_warning(png_ptr, "Only compression windows >= 256 supported by PNG"); + +#ifndef WBITS_8_OK + /* Avoid libpng bug with 256-byte windows */ + if (window_bits == 8) + { + png_warning(png_ptr, "Compression window is being reset to 512"); + window_bits = 9; + } + +#endif + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS; + png_ptr->zlib_window_bits = window_bits; +} + +void PNGAPI +png_set_compression_method(png_structp png_ptr, int method) +{ + png_debug(1, "in png_set_compression_method"); + + if (png_ptr == NULL) + return; + + if (method != 8) + png_warning(png_ptr, "Only compression method 8 is supported by PNG"); + + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD; + png_ptr->zlib_method = method; +} + +void PNGAPI +png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn) +{ + if (png_ptr == NULL) + return; + + png_ptr->write_row_fn = write_row_fn; +} + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED +void PNGAPI +png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr + write_user_transform_fn) +{ + png_debug(1, "in png_set_write_user_transform_fn"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= PNG_USER_TRANSFORM; + png_ptr->write_user_transform_fn = write_user_transform_fn; +} +#endif + + +#ifdef PNG_INFO_IMAGE_SUPPORTED +void PNGAPI +png_write_png(png_structp png_ptr, png_infop info_ptr, + int transforms, voidp params) +{ + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* Write the file header information. */ + png_write_info(png_ptr, info_ptr); + + /* ------ these transformations don't touch the info structure ------- */ + +#ifdef PNG_WRITE_INVERT_SUPPORTED + /* Invert monochrome pixels */ + if (transforms & PNG_TRANSFORM_INVERT_MONO) + png_set_invert_mono(png_ptr); +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED + /* Shift the pixels up to a legal bit depth and fill in + * as appropriate to correctly scale the image. + */ + if ((transforms & PNG_TRANSFORM_SHIFT) + && (info_ptr->valid & PNG_INFO_sBIT)) + png_set_shift(png_ptr, &info_ptr->sig_bit); +#endif + +#ifdef PNG_WRITE_PACK_SUPPORTED + /* Pack pixels into bytes */ + if (transforms & PNG_TRANSFORM_PACKING) + png_set_packing(png_ptr); +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED + /* Swap location of alpha bytes from ARGB to RGBA */ + if (transforms & PNG_TRANSFORM_SWAP_ALPHA) + png_set_swap_alpha(png_ptr); +#endif + +#ifdef PNG_WRITE_FILLER_SUPPORTED + /* Pack XRGB/RGBX/ARGB/RGBA into * RGB (4 channels -> 3 channels) */ + if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER) + png_set_filler(png_ptr, 0, PNG_FILLER_AFTER); + + else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) + png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE); +#endif + +#ifdef PNG_WRITE_BGR_SUPPORTED + /* Flip BGR pixels to RGB */ + if (transforms & PNG_TRANSFORM_BGR) + png_set_bgr(png_ptr); +#endif + +#ifdef PNG_WRITE_SWAP_SUPPORTED + /* Swap bytes of 16-bit files to most significant byte first */ + if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) + png_set_swap(png_ptr); +#endif + +#ifdef PNG_WRITE_PACKSWAP_SUPPORTED + /* Swap bits of 1, 2, 4 bit packed pixel formats */ + if (transforms & PNG_TRANSFORM_PACKSWAP) + png_set_packswap(png_ptr); +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel from opacity to transparency */ + if (transforms & PNG_TRANSFORM_INVERT_ALPHA) + png_set_invert_alpha(png_ptr); +#endif + + /* ----------------------- end of transformations ------------------- */ + + /* Write the bits */ + if (info_ptr->valid & PNG_INFO_IDAT) + png_write_image(png_ptr, info_ptr->row_pointers); + + /* It is REQUIRED to call this to finish writing the rest of the file */ + png_write_end(png_ptr, info_ptr); + + PNG_UNUSED(transforms) /* Quiet compiler warnings */ + PNG_UNUSED(params) +} +#endif +#endif /* PNG_WRITE_SUPPORTED */ |