| |
| /* pngwrite.c - general routines to write a PNG file |
| * |
| * Copyright (c) 2018-2022 Cosmin Truta |
| * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson |
| * Copyright (c) 1996-1997 Andreas Dilger |
| * 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_SIMPLIFIED_WRITE_STDIO_SUPPORTED |
| # include <errno.h> |
| #endif /* SIMPLIFIED_WRITE_STDIO */ |
| |
| #ifdef PNG_WRITE_SUPPORTED |
| |
| #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED |
| /* Write out all the unknown chunks for the current given location */ |
| static void |
| write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr, |
| unsigned int where) |
| { |
| if (info_ptr->unknown_chunks_num != 0) |
| { |
| png_const_unknown_chunkp up; |
| |
| png_debug(5, "writing extra chunks"); |
| |
| for (up = info_ptr->unknown_chunks; |
| up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; |
| ++up) |
| if ((up->location & where) != 0) |
| { |
| /* If per-chunk unknown chunk handling is enabled use it, otherwise |
| * just write the chunks the application has set. |
| */ |
| #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED |
| int keep = png_handle_as_unknown(png_ptr, up->name); |
| |
| /* NOTE: this code is radically different from the read side in the |
| * matter of handling an ancillary unknown chunk. In the read side |
| * the default behavior is to discard it, in the code below the default |
| * behavior is to write it. Critical chunks are, however, only |
| * written if explicitly listed or if the default is set to write all |
| * unknown chunks. |
| * |
| * The default handling is also slightly weird - it is not possible to |
| * stop the writing of all unsafe-to-copy chunks! |
| * |
| * TODO: REVIEW: this would seem to be a bug. |
| */ |
| if (keep != PNG_HANDLE_CHUNK_NEVER && |
| ((up->name[3] & 0x20) /* safe-to-copy overrides everything */ || |
| keep == PNG_HANDLE_CHUNK_ALWAYS || |
| (keep == PNG_HANDLE_CHUNK_AS_DEFAULT && |
| png_ptr->unknown_default == PNG_HANDLE_CHUNK_ALWAYS))) |
| #endif |
| { |
| /* TODO: review, what is wrong with a zero length unknown chunk? */ |
| 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 /* WRITE_UNKNOWN_CHUNKS */ |
| |
| /* 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_structrp png_ptr, png_const_inforp 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) == 0) |
| { |
| /* Write PNG signature */ |
| png_write_sig(png_ptr); |
| |
| #ifdef PNG_MNG_FEATURES_SUPPORTED |
| if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0 && \ |
| png_ptr->mng_features_permitted != 0) |
| { |
| 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. |
| * |
| * 1.6.0: COLORSPACE support controls the writing of these chunks too, and |
| * the chunks will be written if the WRITE routine is there and |
| * information * is available in the COLORSPACE. (See |
| * png_colorspace_sync_info in png.c for where the valid flags get set.) |
| * |
| * Under certain circumstances the colorspace can be invalidated without |
| * syncing the info_struct 'valid' flags; this happens if libpng detects |
| * an error and calls png_error while the color space is being set, yet |
| * the application continues writing the PNG. So check the 'invalid' |
| * flag here too. |
| */ |
| #ifdef PNG_GAMMA_SUPPORTED |
| # ifdef PNG_WRITE_gAMA_SUPPORTED |
| if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 && |
| (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) != 0 && |
| (info_ptr->valid & PNG_INFO_gAMA) != 0) |
| png_write_gAMA_fixed(png_ptr, info_ptr->colorspace.gamma); |
| # endif |
| #endif |
| |
| #ifdef PNG_COLORSPACE_SUPPORTED |
| /* Write only one of sRGB or an ICC profile. If a profile was supplied |
| * and it matches one of the known sRGB ones issue a warning. |
| */ |
| # ifdef PNG_WRITE_iCCP_SUPPORTED |
| if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 && |
| (info_ptr->valid & PNG_INFO_iCCP) != 0) |
| { |
| # ifdef PNG_WRITE_sRGB_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_sRGB) != 0) |
| png_app_warning(png_ptr, |
| "profile matches sRGB but writing iCCP instead"); |
| # endif |
| |
| png_write_iCCP(png_ptr, info_ptr->iccp_name, |
| info_ptr->iccp_profile); |
| } |
| # ifdef PNG_WRITE_sRGB_SUPPORTED |
| else |
| # endif |
| # endif |
| |
| # ifdef PNG_WRITE_sRGB_SUPPORTED |
| if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 && |
| (info_ptr->valid & PNG_INFO_sRGB) != 0) |
| png_write_sRGB(png_ptr, info_ptr->colorspace.rendering_intent); |
| # endif /* WRITE_sRGB */ |
| #endif /* COLORSPACE */ |
| |
| #ifdef PNG_WRITE_sBIT_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_sBIT) != 0) |
| png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type); |
| #endif |
| |
| #ifdef PNG_COLORSPACE_SUPPORTED |
| # ifdef PNG_WRITE_cHRM_SUPPORTED |
| if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 && |
| (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) != 0 && |
| (info_ptr->valid & PNG_INFO_cHRM) != 0) |
| png_write_cHRM_fixed(png_ptr, &info_ptr->colorspace.end_points_xy); |
| # endif |
| #endif |
| |
| #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED |
| write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_IHDR); |
| #endif |
| |
| png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE; |
| } |
| } |
| |
| void PNGAPI |
| png_write_info(png_structrp png_ptr, png_const_inforp 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) != 0) |
| 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) !=0) |
| { |
| #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
| /* Invert the alpha channel (in tRNS) */ |
| if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0 && |
| info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
| { |
| int j, jend; |
| |
| jend = info_ptr->num_trans; |
| if (jend > PNG_MAX_PALETTE_LENGTH) |
| jend = PNG_MAX_PALETTE_LENGTH; |
| |
| for (j = 0; j<jend; ++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) != 0) |
| png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type); |
| #endif |
| |
| #ifdef PNG_WRITE_eXIf_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_eXIf) != 0) |
| png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif); |
| #endif |
| |
| #ifdef PNG_WRITE_hIST_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_hIST) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| { |
| 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) != 0) |
| 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); |
| /* Mark this chunk as written */ |
| if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; |
| else |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; |
| #else |
| png_warning(png_ptr, "Unable to write international text"); |
| #endif |
| } |
| |
| /* 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, info_ptr->text[i].compression); |
| /* Mark this chunk as written */ |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; |
| #else |
| png_warning(png_ptr, "Unable to write compressed text"); |
| #endif |
| } |
| |
| 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 |
| write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_PLTE); |
| #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_structrp png_ptr, png_inforp info_ptr) |
| { |
| png_debug(1, "in png_write_end"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| if ((png_ptr->mode & PNG_HAVE_IDAT) == 0) |
| png_error(png_ptr, "No IDATs written into file"); |
| |
| #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED |
| if (png_ptr->num_palette_max > png_ptr->num_palette) |
| png_benign_error(png_ptr, "Wrote palette index exceeding num_palette"); |
| #endif |
| |
| /* 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) != 0 && |
| (png_ptr->mode & PNG_WROTE_tIME) == 0) |
| 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); |
| /* Mark this chunk as written */ |
| if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; |
| else |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; |
| #else |
| png_warning(png_ptr, "Unable to write international text"); |
| #endif |
| } |
| |
| 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, info_ptr->text[i].compression); |
| /* Mark this chunk as written */ |
| info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; |
| #else |
| png_warning(png_ptr, "Unable to write compressed text"); |
| #endif |
| } |
| |
| 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 |
| png_warning(png_ptr, "Unable to write uncompressed text"); |
| #endif |
| } |
| } |
| #endif |
| |
| #ifdef PNG_WRITE_eXIf_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_eXIf) != 0) |
| png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif); |
| #endif |
| |
| #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED |
| write_unknown_chunks(png_ptr, info_ptr, PNG_AFTER_IDAT); |
| #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 |
| void PNGAPI |
| png_convert_from_struct_tm(png_timep ptime, const struct tm * 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); |
| if (tbuf == NULL) |
| { |
| /* TODO: add a safe function which takes a png_ptr argument and raises |
| * a png_error if the ttime argument is invalid and the call to gmtime |
| * fails as a consequence. |
| */ |
| memset(ptime, 0, sizeof(*ptime)); |
| return; |
| } |
| |
| 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) |
| { |
| #ifndef PNG_USER_MEM_SUPPORTED |
| png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr, |
| error_fn, warn_fn, NULL, NULL, NULL); |
| #else |
| 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 */ |
| 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) |
| { |
| png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr, |
| error_fn, warn_fn, mem_ptr, malloc_fn, free_fn); |
| #endif /* USER_MEM */ |
| if (png_ptr != NULL) |
| { |
| /* Set the zlib control values to defaults; they can be overridden by the |
| * application after the struct has been created. |
| */ |
| png_ptr->zbuffer_size = PNG_ZBUF_SIZE; |
| |
| /* The 'zlib_strategy' setting is irrelevant because png_default_claim in |
| * pngwutil.c defaults it according to whether or not filters will be |
| * used, and ignores this setting. |
| */ |
| png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY; |
| png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION; |
| png_ptr->zlib_mem_level = 8; |
| png_ptr->zlib_window_bits = 15; |
| png_ptr->zlib_method = 8; |
| |
| #ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED |
| png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY; |
| png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION; |
| png_ptr->zlib_text_mem_level = 8; |
| png_ptr->zlib_text_window_bits = 15; |
| png_ptr->zlib_text_method = 8; |
| #endif /* WRITE_COMPRESSED_TEXT */ |
| |
| /* This is a highly dubious configuration option; by default it is off, |
| * but it may be appropriate for private builds that are testing |
| * extensions not conformant to the current specification, or of |
| * applications that must not fail to write at all costs! |
| */ |
| #ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED |
| /* In stable builds only warn if an application error can be completely |
| * handled. |
| */ |
| png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN; |
| #endif |
| |
| /* App warnings are warnings in release (or release candidate) builds but |
| * are errors during development. |
| */ |
| #if PNG_RELEASE_BUILD |
| png_ptr->flags |= PNG_FLAG_APP_WARNINGS_WARN; |
| #endif |
| |
| /* TODO: delay this, it can be done in png_init_io() (if the app doesn't |
| * do it itself) avoiding setting the default function if it is not |
| * required. |
| */ |
| png_set_write_fn(png_ptr, NULL, NULL, NULL); |
| } |
| |
| 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_structrp 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_structrp 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); |
| } |
| } |
| } |
| |
| #ifdef PNG_MNG_FEATURES_SUPPORTED |
| /* Performs intrapixel differencing */ |
| static void |
| png_do_write_intrapixel(png_row_infop row_info, png_bytep row) |
| { |
| png_debug(1, "in png_do_write_intrapixel"); |
| |
| if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0) |
| { |
| int bytes_per_pixel; |
| png_uint_32 row_width = row_info->width; |
| if (row_info->bit_depth == 8) |
| { |
| png_bytep rp; |
| png_uint_32 i; |
| |
| if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
| bytes_per_pixel = 3; |
| |
| else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| bytes_per_pixel = 4; |
| |
| else |
| return; |
| |
| for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) |
| { |
| *(rp) = (png_byte)(*rp - *(rp + 1)); |
| *(rp + 2) = (png_byte)(*(rp + 2) - *(rp + 1)); |
| } |
| } |
| |
| #ifdef PNG_WRITE_16BIT_SUPPORTED |
| else if (row_info->bit_depth == 16) |
| { |
| png_bytep rp; |
| png_uint_32 i; |
| |
| if (row_info->color_type == PNG_COLOR_TYPE_RGB) |
| bytes_per_pixel = 6; |
| |
| else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| bytes_per_pixel = 8; |
| |
| else |
| return; |
| |
| for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) |
| { |
| png_uint_32 s0 = (png_uint_32)(*(rp ) << 8) | *(rp + 1); |
| png_uint_32 s1 = (png_uint_32)(*(rp + 2) << 8) | *(rp + 3); |
| png_uint_32 s2 = (png_uint_32)(*(rp + 4) << 8) | *(rp + 5); |
| png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL); |
| png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL); |
| *(rp ) = (png_byte)(red >> 8); |
| *(rp + 1) = (png_byte)red; |
| *(rp + 4) = (png_byte)(blue >> 8); |
| *(rp + 5) = (png_byte)blue; |
| } |
| } |
| #endif /* WRITE_16BIT */ |
| } |
| } |
| #endif /* MNG_FEATURES */ |
| |
| /* Called by user to write a row of image data */ |
| void PNGAPI |
| png_write_row(png_structrp png_ptr, png_const_bytep row) |
| { |
| /* 1.5.6: moved from png_struct to be a local structure: */ |
| png_row_info row_info; |
| |
| 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) == 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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) != 0) |
| 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 != 0 && |
| (png_ptr->transformations & PNG_INTERLACE) != 0) |
| { |
| switch (png_ptr->pass) |
| { |
| case 0: |
| if ((png_ptr->row_number & 0x07) != 0) |
| { |
| png_write_finish_row(png_ptr); |
| return; |
| } |
| break; |
| |
| case 1: |
| if ((png_ptr->row_number & 0x07) != 0 || 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) != 0 || 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) != 0 || png_ptr->width < 2) |
| { |
| png_write_finish_row(png_ptr); |
| return; |
| } |
| break; |
| |
| case 6: |
| if ((png_ptr->row_number & 0x01) == 0) |
| { |
| png_write_finish_row(png_ptr); |
| return; |
| } |
| break; |
| |
| default: /* error: ignore it */ |
| break; |
| } |
| } |
| #endif |
| |
| /* Set up row info for transformations */ |
| row_info.color_type = png_ptr->color_type; |
| row_info.width = png_ptr->usr_width; |
| row_info.channels = png_ptr->usr_channels; |
| row_info.bit_depth = png_ptr->usr_bit_depth; |
| row_info.pixel_depth = (png_byte)(row_info.bit_depth * row_info.channels); |
| row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width); |
| |
| png_debug1(3, "row_info->color_type = %d", row_info.color_type); |
| png_debug1(3, "row_info->width = %u", row_info.width); |
| png_debug1(3, "row_info->channels = %d", row_info.channels); |
| png_debug1(3, "row_info->bit_depth = %d", row_info.bit_depth); |
| png_debug1(3, "row_info->pixel_depth = %d", row_info.pixel_depth); |
| png_debug1(3, "row_info->rowbytes = %lu", (unsigned long)row_info.rowbytes); |
| |
| /* Copy user's row into buffer, leaving room for filter byte. */ |
| memcpy(png_ptr->row_buf + 1, row, row_info.rowbytes); |
| |
| #ifdef PNG_WRITE_INTERLACING_SUPPORTED |
| /* Handle interlacing */ |
| if (png_ptr->interlaced && png_ptr->pass < 6 && |
| (png_ptr->transformations & PNG_INTERLACE) != 0) |
| { |
| png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass); |
| /* This should always get caught above, but still ... */ |
| if (row_info.width == 0) |
| { |
| png_write_finish_row(png_ptr); |
| return; |
| } |
| } |
| #endif |
| |
| #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED |
| /* Handle other transformations */ |
| if (png_ptr->transformations != 0) |
| png_do_write_transformations(png_ptr, &row_info); |
| #endif |
| |
| /* At this point the row_info pixel depth must match the 'transformed' depth, |
| * which is also the output depth. |
| */ |
| if (row_info.pixel_depth != png_ptr->pixel_depth || |
| row_info.pixel_depth != png_ptr->transformed_pixel_depth) |
| png_error(png_ptr, "internal write transform logic error"); |
| |
| #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) != 0 && |
| (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) |
| { |
| /* Intrapixel differencing */ |
| png_do_write_intrapixel(&row_info, png_ptr->row_buf + 1); |
| } |
| #endif |
| |
| /* Added at libpng-1.5.10 */ |
| #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED |
| /* Check for out-of-range palette index */ |
| if (row_info.color_type == PNG_COLOR_TYPE_PALETTE && |
| png_ptr->num_palette_max >= 0) |
| png_do_check_palette_indexes(png_ptr, &row_info); |
| #endif |
| |
| /* Find a filter if necessary, filter the row and write it out. */ |
| png_write_find_filter(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_structrp png_ptr, int nrows) |
| { |
| png_debug(1, "in png_set_flush"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->flush_dist = (nrows < 0 ? 0 : (png_uint_32)nrows); |
| } |
| |
| /* Flush the current output buffers now */ |
| void PNGAPI |
| png_write_flush(png_structrp png_ptr) |
| { |
| 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; |
| |
| png_compress_IDAT(png_ptr, NULL, 0, Z_SYNC_FLUSH); |
| png_ptr->flush_rows = 0; |
| png_flush(png_ptr); |
| } |
| #endif /* WRITE_FLUSH */ |
| |
| /* Free any memory used in png_ptr struct without freeing the struct itself. */ |
| static void |
| png_write_destroy(png_structrp png_ptr) |
| { |
| png_debug(1, "in png_write_destroy"); |
| |
| /* Free any memory zlib uses */ |
| if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0) |
| deflateEnd(&png_ptr->zstream); |
| |
| /* Free our memory. png_free checks NULL for us. */ |
| png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list); |
| png_free(png_ptr, png_ptr->row_buf); |
| png_ptr->row_buf = NULL; |
| #ifdef PNG_WRITE_FILTER_SUPPORTED |
| png_free(png_ptr, png_ptr->prev_row); |
| png_free(png_ptr, png_ptr->try_row); |
| png_free(png_ptr, png_ptr->tst_row); |
| png_ptr->prev_row = NULL; |
| png_ptr->try_row = NULL; |
| png_ptr->tst_row = NULL; |
| #endif |
| |
| #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED |
| png_free(png_ptr, png_ptr->chunk_list); |
| png_ptr->chunk_list = NULL; |
| #endif |
| |
| /* The error handling and memory handling information is left intact at this |
| * point: the jmp_buf may still have to be freed. See png_destroy_png_struct |
| * for how this happens. |
| */ |
| } |
| |
| /* Free all memory used by the write. |
| * In libpng 1.6.0 this API changed quietly to no longer accept a NULL value for |
| * *png_ptr_ptr. Prior to 1.6.0 it would accept such a value and it would free |
| * the passed in info_structs but it would quietly fail to free any of the data |
| * inside them. In 1.6.0 it quietly does nothing (it has to be quiet because it |
| * has no png_ptr.) |
| */ |
| void PNGAPI |
| png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr) |
| { |
| png_debug(1, "in png_destroy_write_struct"); |
| |
| if (png_ptr_ptr != NULL) |
| { |
| png_structrp png_ptr = *png_ptr_ptr; |
| |
| if (png_ptr != NULL) /* added in libpng 1.6.0 */ |
| { |
| png_destroy_info_struct(png_ptr, info_ptr_ptr); |
| |
| *png_ptr_ptr = NULL; |
| png_write_destroy(png_ptr); |
| png_destroy_png_struct(png_ptr); |
| } |
| } |
| } |
| |
| /* Allow the application to select one or more row filters to use. */ |
| void PNGAPI |
| png_set_filter(png_structrp 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) != 0 && |
| (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_app_error(png_ptr, "Unknown row filter for method 0"); |
| #endif /* WRITE_FILTER */ |
| /* FALLTHROUGH */ |
| 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_app_error(png_ptr, "Unknown row filter for method 0"); |
| #endif /* WRITE_FILTER */ |
| } |
| |
| #ifdef 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 remove them |
| * or add them back after the start of compression. |
| * |
| * NOTE: this is a nasty constraint on the code, because it means that the |
| * prev_row buffer must be maintained even if there are currently no |
| * 'prev_row' requiring filters active. |
| */ |
| if (png_ptr->row_buf != NULL) |
| { |
| int num_filters; |
| png_alloc_size_t buf_size; |
| |
| /* Repeat the checks in png_write_start_row; 1 pixel high or wide |
| * images cannot benefit from certain filters. If this isn't done here |
| * the check below will fire on 1 pixel high images. |
| */ |
| if (png_ptr->height == 1) |
| filters &= ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH); |
| |
| if (png_ptr->width == 1) |
| filters &= ~(PNG_FILTER_SUB|PNG_FILTER_AVG|PNG_FILTER_PAETH); |
| |
| if ((filters & (PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH)) != 0 |
| && png_ptr->prev_row == NULL) |
| { |
| /* This is the error case, however it is benign - the previous row |
| * is not available so the filter can't be used. Just warn here. |
| */ |
| png_app_warning(png_ptr, |
| "png_set_filter: UP/AVG/PAETH cannot be added after start"); |
| filters &= ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH); |
| } |
| |
| num_filters = 0; |
| |
| if (filters & PNG_FILTER_SUB) |
| num_filters++; |
| |
| if (filters & PNG_FILTER_UP) |
| num_filters++; |
| |
| if (filters & PNG_FILTER_AVG) |
| num_filters++; |
| |
| if (filters & PNG_FILTER_PAETH) |
| num_filters++; |
| |
| /* Allocate needed row buffers if they have not already been |
| * allocated. |
| */ |
| buf_size = PNG_ROWBYTES(png_ptr->usr_channels * png_ptr->usr_bit_depth, |
| png_ptr->width) + 1; |
| |
| if (png_ptr->try_row == NULL) |
| png_ptr->try_row = png_voidcast(png_bytep, |
| png_malloc(png_ptr, buf_size)); |
| |
| if (num_filters > 1) |
| { |
| if (png_ptr->tst_row == NULL) |
| png_ptr->tst_row = png_voidcast(png_bytep, |
| png_malloc(png_ptr, buf_size)); |
| } |
| } |
| png_ptr->do_filter = (png_byte)filters; |
| #endif |
| } |
| else |
| png_error(png_ptr, "Unknown custom filter method"); |
| } |
| |
| #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */ |
| /* Provide floating and fixed point APIs */ |
| #ifdef PNG_FLOATING_POINT_SUPPORTED |
| void PNGAPI |
| png_set_filter_heuristics(png_structrp png_ptr, int heuristic_method, |
| int num_weights, png_const_doublep filter_weights, |
| png_const_doublep filter_costs) |
| { |
| PNG_UNUSED(png_ptr) |
| PNG_UNUSED(heuristic_method) |
| PNG_UNUSED(num_weights) |
| PNG_UNUSED(filter_weights) |
| PNG_UNUSED(filter_costs) |
| } |
| #endif /* FLOATING_POINT */ |
| |
| #ifdef PNG_FIXED_POINT_SUPPORTED |
| void PNGAPI |
| png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method, |
| int num_weights, png_const_fixed_point_p filter_weights, |
| png_const_fixed_point_p filter_costs) |
| { |
| PNG_UNUSED(png_ptr) |
| PNG_UNUSED(heuristic_method) |
| PNG_UNUSED(num_weights) |
| PNG_UNUSED(filter_weights) |
| PNG_UNUSED(filter_costs) |
| } |
| #endif /* FIXED_POINT */ |
| #endif /* WRITE_WEIGHTED_FILTER */ |
| |
| #ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED |
| void PNGAPI |
| png_set_compression_level(png_structrp png_ptr, int level) |
| { |
| png_debug(1, "in png_set_compression_level"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->zlib_level = level; |
| } |
| |
| void PNGAPI |
| png_set_compression_mem_level(png_structrp png_ptr, int mem_level) |
| { |
| png_debug(1, "in png_set_compression_mem_level"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->zlib_mem_level = mem_level; |
| } |
| |
| void PNGAPI |
| png_set_compression_strategy(png_structrp png_ptr, int strategy) |
| { |
| png_debug(1, "in png_set_compression_strategy"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| /* The flag setting here prevents the libpng dynamic selection of strategy. |
| */ |
| png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY; |
| png_ptr->zlib_strategy = strategy; |
| } |
| |
| /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
| * smaller value of window_bits if it can do so safely. |
| */ |
| void PNGAPI |
| png_set_compression_window_bits(png_structrp png_ptr, int window_bits) |
| { |
| if (png_ptr == NULL) |
| return; |
| |
| /* Prior to 1.6.0 this would warn but then set the window_bits value. This |
| * meant that negative window bits values could be selected that would cause |
| * libpng to write a non-standard PNG file with raw deflate or gzip |
| * compressed IDAT or ancillary chunks. Such files can be read and there is |
| * no warning on read, so this seems like a very bad idea. |
| */ |
| if (window_bits > 15) |
| { |
| png_warning(png_ptr, "Only compression windows <= 32k supported by PNG"); |
| window_bits = 15; |
| } |
| |
| else if (window_bits < 8) |
| { |
| png_warning(png_ptr, "Only compression windows >= 256 supported by PNG"); |
| window_bits = 8; |
| } |
| |
| png_ptr->zlib_window_bits = window_bits; |
| } |
| |
| void PNGAPI |
| png_set_compression_method(png_structrp png_ptr, int method) |
| { |
| png_debug(1, "in png_set_compression_method"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| /* This would produce an invalid PNG file if it worked, but it doesn't and |
| * deflate will fault it, so it is harmless to just warn here. |
| */ |
| if (method != 8) |
| png_warning(png_ptr, "Only compression method 8 is supported by PNG"); |
| |
| png_ptr->zlib_method = method; |
| } |
| #endif /* WRITE_CUSTOMIZE_COMPRESSION */ |
| |
| /* The following were added to libpng-1.5.4 */ |
| #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED |
| void PNGAPI |
| png_set_text_compression_level(png_structrp png_ptr, int level) |
| { |
| png_debug(1, "in png_set_text_compression_level"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->zlib_text_level = level; |
| } |
| |
| void PNGAPI |
| png_set_text_compression_mem_level(png_structrp png_ptr, int mem_level) |
| { |
| png_debug(1, "in png_set_text_compression_mem_level"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->zlib_text_mem_level = mem_level; |
| } |
| |
| void PNGAPI |
| png_set_text_compression_strategy(png_structrp png_ptr, int strategy) |
| { |
| png_debug(1, "in png_set_text_compression_strategy"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| png_ptr->zlib_text_strategy = strategy; |
| } |
| |
| /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a |
| * smaller value of window_bits if it can do so safely. |
| */ |
| void PNGAPI |
| png_set_text_compression_window_bits(png_structrp 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"); |
| window_bits = 15; |
| } |
| |
| else if (window_bits < 8) |
| { |
| png_warning(png_ptr, "Only compression windows >= 256 supported by PNG"); |
| window_bits = 8; |
| } |
| |
| png_ptr->zlib_text_window_bits = window_bits; |
| } |
| |
| void PNGAPI |
| png_set_text_compression_method(png_structrp png_ptr, int method) |
| { |
| png_debug(1, "in png_set_text_compression_method"); |
| |
| if (png_ptr == NULL) |
| return; |
| |
| if (method != 8) |
| png_warning(png_ptr, "Only compression method 8 is supported by PNG"); |
| |
| png_ptr->zlib_text_method = method; |
| } |
| #endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */ |
| /* end of API added to libpng-1.5.4 */ |
| |
| void PNGAPI |
| png_set_write_status_fn(png_structrp 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_structrp 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_structrp png_ptr, png_inforp info_ptr, |
| int transforms, voidp params) |
| { |
| if (png_ptr == NULL || info_ptr == NULL) |
| return; |
| |
| if ((info_ptr->valid & PNG_INFO_IDAT) == 0) |
| { |
| png_app_error(png_ptr, "no rows for png_write_image to write"); |
| return; |
| } |
| |
| /* Write the file header information. */ |
| png_write_info(png_ptr, info_ptr); |
| |
| /* ------ these transformations don't touch the info structure ------- */ |
| |
| /* Invert monochrome pixels */ |
| if ((transforms & PNG_TRANSFORM_INVERT_MONO) != 0) |
| #ifdef PNG_WRITE_INVERT_SUPPORTED |
| png_set_invert_mono(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_MONO not supported"); |
| #endif |
| |
| /* Shift the pixels up to a legal bit depth and fill in |
| * as appropriate to correctly scale the image. |
| */ |
| if ((transforms & PNG_TRANSFORM_SHIFT) != 0) |
| #ifdef PNG_WRITE_SHIFT_SUPPORTED |
| if ((info_ptr->valid & PNG_INFO_sBIT) != 0) |
| png_set_shift(png_ptr, &info_ptr->sig_bit); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_SHIFT not supported"); |
| #endif |
| |
| /* Pack pixels into bytes */ |
| if ((transforms & PNG_TRANSFORM_PACKING) != 0) |
| #ifdef PNG_WRITE_PACK_SUPPORTED |
| png_set_packing(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_PACKING not supported"); |
| #endif |
| |
| /* Swap location of alpha bytes from ARGB to RGBA */ |
| if ((transforms & PNG_TRANSFORM_SWAP_ALPHA) != 0) |
| #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED |
| png_set_swap_alpha(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ALPHA not supported"); |
| #endif |
| |
| /* Remove a filler (X) from XRGB/RGBX/AG/GA into to convert it into |
| * RGB, note that the code expects the input color type to be G or RGB; no |
| * alpha channel. |
| */ |
| if ((transforms & (PNG_TRANSFORM_STRIP_FILLER_AFTER| |
| PNG_TRANSFORM_STRIP_FILLER_BEFORE)) != 0) |
| { |
| #ifdef PNG_WRITE_FILLER_SUPPORTED |
| if ((transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER) != 0) |
| { |
| if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0) |
| png_app_error(png_ptr, |
| "PNG_TRANSFORM_STRIP_FILLER: BEFORE+AFTER not supported"); |
| |
| /* Continue if ignored - this is the pre-1.6.10 behavior */ |
| png_set_filler(png_ptr, 0, PNG_FILLER_AFTER); |
| } |
| |
| else if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0) |
| png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_STRIP_FILLER not supported"); |
| #endif |
| } |
| |
| /* Flip BGR pixels to RGB */ |
| if ((transforms & PNG_TRANSFORM_BGR) != 0) |
| #ifdef PNG_WRITE_BGR_SUPPORTED |
| png_set_bgr(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_BGR not supported"); |
| #endif |
| |
| /* Swap bytes of 16-bit files to most significant byte first */ |
| if ((transforms & PNG_TRANSFORM_SWAP_ENDIAN) != 0) |
| #ifdef PNG_WRITE_SWAP_SUPPORTED |
| png_set_swap(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ENDIAN not supported"); |
| #endif |
| |
| /* Swap bits of 1-bit, 2-bit, 4-bit packed pixel formats */ |
| if ((transforms & PNG_TRANSFORM_PACKSWAP) != 0) |
| #ifdef PNG_WRITE_PACKSWAP_SUPPORTED |
| png_set_packswap(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_PACKSWAP not supported"); |
| #endif |
| |
| /* Invert the alpha channel from opacity to transparency */ |
| if ((transforms & PNG_TRANSFORM_INVERT_ALPHA) != 0) |
| #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED |
| png_set_invert_alpha(png_ptr); |
| #else |
| png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_ALPHA not supported"); |
| #endif |
| |
| /* ----------------------- end of transformations ------------------- */ |
| |
| /* Write the bits */ |
| 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(params) |
| } |
| #endif |
| |
| |
| #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED |
| /* Initialize the write structure - general purpose utility. */ |
| static int |
| png_image_write_init(png_imagep image) |
| { |
| png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, image, |
| png_safe_error, png_safe_warning); |
| |
| if (png_ptr != NULL) |
| { |
| png_infop info_ptr = png_create_info_struct(png_ptr); |
| |
| if (info_ptr != NULL) |
| { |
| png_controlp control = png_voidcast(png_controlp, |
| png_malloc_warn(png_ptr, (sizeof *control))); |
| |
| if (control != NULL) |
| { |
| memset(control, 0, (sizeof *control)); |
| |
| control->png_ptr = png_ptr; |
| control->info_ptr = info_ptr; |
| control->for_write = 1; |
| |
| image->opaque = control; |
| return 1; |
| } |
| |
| /* Error clean up */ |
| png_destroy_info_struct(png_ptr, &info_ptr); |
| } |
| |
| png_destroy_write_struct(&png_ptr, NULL); |
| } |
| |
| return png_image_error(image, "png_image_write_: out of memory"); |
| } |
| |
| /* Arguments to png_image_write_main: */ |
| typedef struct |
| { |
| /* Arguments: */ |
| png_imagep image; |
| png_const_voidp buffer; |
| png_int_32 row_stride; |
| png_const_voidp colormap; |
| int convert_to_8bit; |
| /* Local variables: */ |
| png_const_voidp first_row; |
| ptrdiff_t row_bytes; |
| png_voidp local_row; |
| /* Byte count for memory writing */ |
| png_bytep memory; |
| png_alloc_size_t memory_bytes; /* not used for STDIO */ |
| png_alloc_size_t output_bytes; /* running total */ |
| } png_image_write_control; |
| |
| /* Write png_uint_16 input to a 16-bit PNG; the png_ptr has already been set to |
| * do any necessary byte swapping. The component order is defined by the |
| * png_image format value. |
| */ |
| static int |
| png_write_image_16bit(png_voidp argument) |
| { |
| png_image_write_control *display = png_voidcast(png_image_write_control*, |
| argument); |
| png_imagep image = display->image; |
| png_structrp png_ptr = image->opaque->png_ptr; |
| |
| png_const_uint_16p input_row = png_voidcast(png_const_uint_16p, |
| display->first_row); |
| png_uint_16p output_row = png_voidcast(png_uint_16p, display->local_row); |
| png_uint_16p row_end; |
| unsigned int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? |
| 3 : 1; |
| int aindex = 0; |
| png_uint_32 y = image->height; |
| |
| if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0) |
| { |
| # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED |
| if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0) |
| { |
| aindex = -1; |
| ++input_row; /* To point to the first component */ |
| ++output_row; |
| } |
| else |
| aindex = (int)channels; |
| # else |
| aindex = (int)channels; |
| # endif |
| } |
| |
| else |
| png_error(png_ptr, "png_write_image: internal call error"); |
| |
| /* Work out the output row end and count over this, note that the increment |
| * above to 'row' means that row_end can actually be beyond the end of the |
| * row; this is correct. |
| */ |
| row_end = output_row + image->width * (channels+1); |
| |
| for (; y > 0; --y) |
| { |
| png_const_uint_16p in_ptr = input_row; |
| png_uint_16p out_ptr = output_row; |
| |
| while (out_ptr < row_end) |
| { |
| png_uint_16 alpha = in_ptr[aindex]; |
| png_uint_32 reciprocal = 0; |
| int c; |
| |
| out_ptr[aindex] = alpha; |
| |
| /* Calculate a reciprocal. The correct calculation is simply |
| * component/alpha*65535 << 15. (I.e. 15 bits of precision); this |
| * allows correct rounding by adding .5 before the shift. 'reciprocal' |
| * is only initialized when required. |
| */ |
| if (alpha > 0 && alpha < 65535) |
| reciprocal = ((0xffff<<15)+(alpha>>1))/alpha; |
| |
| c = (int)channels; |
| do /* always at least one channel */ |
| { |
| png_uint_16 component = *in_ptr++; |
| |
| /* The following gives 65535 for an alpha of 0, which is fine, |
| * otherwise if 0/0 is represented as some other value there is more |
| * likely to be a discontinuity which will probably damage |
| * compression when moving from a fully transparent area to a |
| * nearly transparent one. (The assumption here is that opaque |
| * areas tend not to be 0 intensity.) |
| */ |
| if (component >= alpha) |
| component = 65535; |
| |
| /* component<alpha, so component/alpha is less than one and |
| * component*reciprocal is less than 2^31. |
| */ |
| else if (component > 0 && alpha < 65535) |
| { |
| png_uint_32 calc = component * reciprocal; |
| calc += 16384; /* round to nearest */ |
| component = (png_uint_16)(calc >> 15); |
| } |
| |
| *out_ptr++ = component; |
| } |
| while (--c > 0); |
| |
| /* Skip to next component (skip the intervening alpha channel) */ |
| ++in_ptr; |
| ++out_ptr; |
| } |
| |
| png_write_row(png_ptr, png_voidcast(png_const_bytep, display->local_row)); |
| input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16)); |
| } |
| |
| return 1; |
| } |
| |
| /* Given 16-bit input (1 to 4 channels) write 8-bit output. If an alpha channel |
| * is present it must be removed from the components, the components are then |
| * written in sRGB encoding. No components are added or removed. |
| * |
| * Calculate an alpha reciprocal to reverse pre-multiplication. As above the |
| * calculation can be done to 15 bits of accuracy; however, the output needs to |
| * be scaled in the range 0..255*65535, so include that scaling here. |
| */ |
| # define UNP_RECIPROCAL(alpha) ((((0xffff*0xff)<<7)+((alpha)>>1))/(alpha)) |
| |
| static png_byte |
| png_unpremultiply(png_uint_32 component, png_uint_32 alpha, |
| png_uint_32 reciprocal/*from the above macro*/) |
| { |
| /* The following gives 1.0 for an alpha of 0, which is fine, otherwise if 0/0 |
| * is represented as some other value there is more likely to be a |
| * discontinuity which will probably damage compression when moving from a |
| * fully transparent area to a nearly transparent one. (The assumption here |
| * is that opaque areas tend not to be 0 intensity.) |
| * |
| * There is a rounding problem here; if alpha is less than 128 it will end up |
| * as 0 when scaled to 8 bits. To avoid introducing spurious colors into the |
| * output change for this too. |
| */ |
| if (component >= alpha || alpha < 128) |
| return 255; |
| |
| /* component<alpha, so component/alpha is less than one and |
| * component*reciprocal is less than 2^31. |
| */ |
| else if (component > 0) |
| { |
| /* The test is that alpha/257 (rounded) is less than 255, the first value |
| * that becomes 255 is 65407. |
| * NOTE: this must agree with the PNG_DIV257 macro (which must, therefore, |
| * be exact!) [Could also test reciprocal != 0] |
| */ |
| if (alpha < 65407) |
| { |
| component *= reciprocal; |
| component += 64; /* round to nearest */ |
| component >>= 7; |
| } |
| |
| else |
| component *= 255; |
| |
| /* Convert the component to sRGB. */ |
| return (png_byte)PNG_sRGB_FROM_LINEAR(component); |
| } |
| |
| else |
| return 0; |
| } |
| |
| static int |
| png_write_image_8bit(png_voidp argument) |
| { |
| png_image_write_control *display = png_voidcast(png_image_write_control*, |
| argument); |
| png_imagep image = display->image; |
| png_structrp png_ptr = image->opaque->png_ptr; |
| |
| png_const_uint_16p input_row = png_voidcast(png_const_uint_16p, |
| display->first_row); |
| png_bytep output_row = png_voidcast(png_bytep, display->local_row); |
| png_uint_32 y = image->height; |
| unsigned int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? |
| 3 : 1; |
| |
| if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0) |
| { |
| png_bytep row_end; |
| int aindex; |
| |
| # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED |
| if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0) |
| { |
| aindex = -1; |
| ++input_row; /* To point to the first component */ |
| ++output_row; |
| } |
| |
| else |
| # endif |
| aindex = (int)channels; |
| |
| /* Use row_end in place of a loop counter: */ |
| row_end = output_row + image->width * (channels+1); |
| |
| for (; y > 0; --y) |
| { |
| png_const_uint_16p in_ptr = input_row; |
| png_bytep out_ptr = output_row; |
| |
| while (out_ptr < row_end) |
| { |
| png_uint_16 alpha = in_ptr[aindex]; |
| png_byte alphabyte = (png_byte)PNG_DIV257(alpha); |
| png_uint_32 reciprocal = 0; |
| int c; |
| |
| /* Scale and write the alpha channel. */ |
| out_ptr[aindex] = alphabyte; |
| |
| if (alphabyte > 0 && alphabyte < 255) |
| reciprocal = UNP_RECIPROCAL(alpha); |
| |
| c = (int)channels; |
| do /* always at least one channel */ |
| *out_ptr++ = png_unpremultiply(*in_ptr++, alpha, reciprocal); |
| while (--c > 0); |
| |
| /* Skip to next component (skip the intervening alpha channel) */ |
| ++in_ptr; |
| ++out_ptr; |
| } /* while out_ptr < row_end */ |
| |
| png_write_row(png_ptr, png_voidcast(png_const_bytep, |
| display->local_row)); |
| input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16)); |
| } /* while y */ |
| } |
| |
| else |
| { |
| /* No alpha channel, so the row_end really is the end of the row and it |
| * is sufficient to loop over the components one by one. |
| */ |
| png_bytep row_end = output_row + image->width * channels; |
| |
| for (; y > 0; --y) |
| { |
| png_const_uint_16p in_ptr = input_row; |
| png_bytep out_ptr = output_row; |
| |
| while (out_ptr < row_end) |
| { |
| png_uint_32 component = *in_ptr++; |
| |
| component *= 255; |
| *out_ptr++ = (png_byte)PNG_sRGB_FROM_LINEAR(component); |
| } |
| |
| png_write_row(png_ptr, output_row); |
| input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16)); |
| } |
| } |
| |
| return 1; |
| } |
| |
| static void |
| png_image_set_PLTE(png_image_write_control *display) |
| { |
| png_imagep image = display->image; |
| const void *cmap = display->colormap; |
| int entries = image->colormap_entries > 256 ? 256 : |
| (int)image->colormap_entries; |
| |
| /* NOTE: the caller must check for cmap != NULL and entries != 0 */ |
| png_uint_32 format = image->format; |
| unsigned int channels = PNG_IMAGE_SAMPLE_CHANNELS(format); |
| |
| # if defined(PNG_FORMAT_BGR_SUPPORTED) &&\ |
| defined(PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED) |
| int afirst = (format & PNG_FORMAT_FLAG_AFIRST) != 0 && |
| (format & PNG_FORMAT_FLAG_ALPHA) != 0; |
| # else |
| # define afirst 0 |
| # endif |
| |
| # ifdef PNG_FORMAT_BGR_SUPPORTED |
| int bgr = (format & PNG_FORMAT_FLAG_BGR) != 0 ? 2 : 0; |
| # else |
| # define bgr 0 |
| # endif |
| |
| int i, num_trans; |
| png_color palette[256]; |
| png_byte tRNS[256]; |
| |
| memset(tRNS, 255, (sizeof tRNS)); |
| memset(palette, 0, (sizeof palette)); |
| |
| for (i=num_trans=0; i<entries; ++i) |
| { |
| /* This gets automatically converted to sRGB with reversal of the |
| * pre-multiplication if the color-map has an alpha channel. |
| */ |
| if ((format & PNG_FORMAT_FLAG_LINEAR) != 0) |
| { |
| png_const_uint_16p entry = png_voidcast(png_const_uint_16p, cmap); |
| |
| entry += (unsigned int)i * channels; |
| |
| if ((channels & 1) != 0) /* no alpha */ |
| { |
| if (channels >= 3) /* RGB */ |
| { |
| palette[i].blue = (png_byte)PNG_sRGB_FROM_LINEAR(255 * |
| entry[(2 ^ bgr)]); |
| palette[i].green = (png_byte)PNG_sRGB_FROM_LINEAR(255 * |
| entry[1]); |
| palette[i].red = (png_byte)PNG_sRGB_FROM_LINEAR(255 * |
| entry[bgr]); |
| } |
| |
| else /* Gray */ |
| palette[i].blue = palette[i].red = palette[i].green = |
| (png_byte)PNG_sRGB_FROM_LINEAR(255 * *entry); |
| } |
| |
| else /* alpha */ |
| { |
| png_uint_16 alpha = entry[afirst ? 0 : channels-1]; |
| png_byte alphabyte = (png_byte)PNG_DIV257(alpha); |
| png_uint_32 reciprocal = 0; |
| |
| /* Calculate a reciprocal, as in the png_write_image_8bit code above |
| * this is designed to produce a value scaled to 255*65535 when |
| * divided by 128 (i.e. asr 7). |
| */ |
| if (alphabyte > 0 && alphabyte < 255) |
| reciprocal = (((0xffff*0xff)<<7)+(alpha>>1))/alpha; |
| |
| tRNS[i] = alphabyte; |
| if (alphabyte < 255) |
| num_trans = i+1; |
| |
| if (channels >= 3) /* RGB */ |
| { |
| palette[i].blue = png_unpremultiply(entry[afirst + (2 ^ bgr)], |
| alpha, reciprocal); |
| palette[i].green = png_unpremultiply(entry[afirst + 1], alpha, |
| reciprocal); |
| palette[i].red = png_unpremultiply(entry[afirst + bgr], alpha, |
| reciprocal); |
| } |
| |
| else /* gray */ |
| palette[i].blue = palette[i].red = palette[i].green = |
| png_unpremultiply(entry[afirst], alpha, reciprocal); |
| } |
| } |
| |
| else /* Color-map has sRGB values */ |
| { |
| png_const_bytep entry = png_voidcast(png_const_bytep, cmap); |
| |
| entry += (unsigned int)i * channels; |
| |
| switch (channels) |
| { |
| case 4: |
| tRNS[i] = entry[afirst ? 0 : 3]; |
| if (tRNS[i] < 255) |
| num_trans = i+1; |
| /* FALLTHROUGH */ |
| case 3: |
| palette[i].blue = entry[afirst + (2 ^ bgr)]; |
| palette[i].green = entry[afirst + 1]; |
| palette[i].red = entry[afirst + bgr]; |
| break; |
| |
| case 2: |
| tRNS[i] = entry[1 ^ afirst]; |
| if (tRNS[i] < 255) |
| num_trans = i+1; |
| /* FALLTHROUGH */ |
| case 1: |
| palette[i].blue = palette[i].red = palette[i].green = |
| entry[afirst]; |
| break; |
| |
| default: |
| break; |
| } |
| } |
| } |
| |
| # ifdef afirst |
| # undef afirst |
| # endif |
| # ifdef bgr |
| # undef bgr |
| # endif |
| |
| png_set_PLTE(image->opaque->png_ptr, image->opaque->info_ptr, palette, |
| entries); |
| |
| if (num_trans > 0) |
| png_set_tRNS(image->opaque->png_ptr, image->opaque->info_ptr, tRNS, |
| num_trans, NULL); |
| |
| image->colormap_entries = (png_uint_32)entries; |
| } |
| |
| static int |
| png_image_write_main(png_voidp argument) |
| { |
| png_image_write_control *display = png_voidcast(png_image_write_control*, |
| argument); |
| png_imagep image = display->image; |
| png_structrp png_ptr = image->opaque->png_ptr; |
| png_inforp info_ptr = image->opaque->info_ptr; |
| png_uint_32 format = image->format; |
| |
| /* The following four ints are actually booleans */ |
| int colormap = (format & PNG_FORMAT_FLAG_COLORMAP); |
| int linear = !colormap && (format & PNG_FORMAT_FLAG_LINEAR); /* input */ |
| int alpha = !colormap && (format & PNG_FORMAT_FLAG_ALPHA); |
| int write_16bit = linear && (display->convert_to_8bit == 0); |
| |
| # ifdef PNG_BENIGN_ERRORS_SUPPORTED |
| /* Make sure we error out on any bad situation */ |
| png_set_benign_errors(png_ptr, 0/*error*/); |
| # endif |
| |
| /* Default the 'row_stride' parameter if required, also check the row stride |
| * and total image size to ensure that they are within the system limits. |
| */ |
| { |
| unsigned int channels = PNG_IMAGE_PIXEL_CHANNELS(image->format); |
| |
| if (image->width <= 0x7fffffffU/channels) /* no overflow */ |
| { |
| png_uint_32 check; |
| png_uint_32 png_row_stride = image->width * channels; |
| |
| if (display->row_stride == 0) |
| display->row_stride = (png_int_32)/*SAFE*/png_row_stride; |
| |
| if (display->row_stride < 0) |
| check = (png_uint_32)(-display->row_stride); |
| |
| else |
| check = (png_uint_32)display->row_stride; |
| |
| if (check >= png_row_stride) |
| { |
| /* Now check for overflow of the image buffer calculation; this |
| * limits the whole image size to 32 bits for API compatibility with |
| * the current, 32-bit, PNG_IMAGE_BUFFER_SIZE macro. |
| */ |
| if (image->height > 0xffffffffU/png_row_stride) |
| png_error(image->opaque->png_ptr, "memory image too large"); |
| } |
| |
| else |
| png_error(image->opaque->png_ptr, "supplied row stride too small"); |
| } |
| |
| else |
| png_error(image->opaque->png_ptr, "image row stride too large"); |
| } |
| |
| /* Set the required transforms then write the rows in the correct order. */ |
| if ((format & PNG_FORMAT_FLAG_COLORMAP) != 0) |
| { |
| if (display->colormap != NULL && image->colormap_entries > 0) |
| { |
| png_uint_32 entries = image->colormap_entries; |
| |
| png_set_IHDR(png_ptr, info_ptr, image->width, image->height, |
| entries > 16 ? 8 : (entries > 4 ? 4 : (entries > 2 ? 2 : 1)), |
| PNG_COLOR_TYPE_PALETTE, PNG_INTERLACE_NONE, |
| PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); |
| |
| png_image_set_PLTE(display); |
| } |
| |
| else |
| png_error(image->opaque->png_ptr, |
| "no color-map for color-mapped image"); |
| } |
| |
| else |
| png_set_IHDR(png_ptr, info_ptr, image->width, image->height, |
| write_16bit ? 16 : 8, |
| ((format & PNG_FORMAT_FLAG_COLOR) ? PNG_COLOR_MASK_COLOR : 0) + |
| ((format & PNG_FORMAT_FLAG_ALPHA) ? PNG_COLOR_MASK_ALPHA : 0), |
| PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); |
| |
| /* Counter-intuitively the data transformations must be called *after* |
| * png_write_info, not before as in the read code, but the 'set' functions |
| * must still be called before. Just set the color space information, never |
| * write an interlaced image. |
| */ |
| |
| if (write_16bit != 0) |
| { |
| /* The gamma here is 1.0 (linear) and the cHRM chunk matches sRGB. */ |
| png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_LINEAR); |
| |
| if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0) |
| png_set_cHRM_fixed(png_ptr, info_ptr, |
| /* color x y */ |
| /* white */ 31270, 32900, |
| /* red */ 64000, 33000, |
| /* green */ 30000, 60000, |
| /* blue */ 15000, 6000 |
| ); |
| } |
| |
| else if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0) |
| png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_PERCEPTUAL); |
| |
| /* Else writing an 8-bit file and the *colors* aren't sRGB, but the 8-bit |
| * space must still be gamma encoded. |
| */ |
| else |
| png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_sRGB_INVERSE); |
| |
| /* Write the file header. */ |
| png_write_info(png_ptr, info_ptr); |
| |
| /* Now set up the data transformations (*after* the header is written), |
| * remove the handled transformations from the 'format' flags for checking. |
| * |
| * First check for a little endian system if writing 16-bit files. |
| */ |
| if (write_16bit != 0) |
| { |
| png_uint_16 le = 0x0001; |
| |
| if ((*(png_const_bytep) & le) != 0) |
| png_set_swap(png_ptr); |
| } |
| |
| # ifdef PNG_SIMPLIFIED_WRITE_BGR_SUPPORTED |
| if ((format & PNG_FORMAT_FLAG_BGR) != 0) |
| { |
| if (colormap == 0 && (format & PNG_FORMAT_FLAG_COLOR) != 0) |
| png_set_bgr(png_ptr); |
| format &= ~PNG_FORMAT_FLAG_BGR; |
| } |
| # endif |
| |
| # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED |
| if ((format & PNG_FORMAT_FLAG_AFIRST) != 0) |
| { |
| if (colormap == 0 && (format & PNG_FORMAT_FLAG_ALPHA) != 0) |
| png_set_swap_alpha(png_ptr); |
| format &= ~PNG_FORMAT_FLAG_AFIRST; |
| } |
| # endif |
| |
| /* If there are 16 or fewer color-map entries we wrote a lower bit depth |
| * above, but the application data is still byte packed. |
| */ |
| if (colormap != 0 && image->colormap_entries <= 16) |
| png_set_packing(png_ptr); |
| |
| /* That should have handled all (both) the transforms. */ |
| if ((format & ~(png_uint_32)(PNG_FORMAT_FLAG_COLOR | PNG_FORMAT_FLAG_LINEAR | |
| PNG_FORMAT_FLAG_ALPHA | PNG_FORMAT_FLAG_COLORMAP)) != 0) |
| png_error(png_ptr, "png_write_image: unsupported transformation"); |
| |
| { |
| png_const_bytep row = png_voidcast(png_const_bytep, display->buffer); |
| ptrdiff_t row_bytes = display->row_stride; |
| |
| if (linear != 0) |
| row_bytes *= (sizeof (png_uint_16)); |
| |
| if (row_bytes < 0) |
| row += (image->height-1) * (-row_bytes); |
| |
| display->first_row = row; |
| display->row_bytes = row_bytes; |
| } |
| |
| /* Apply 'fast' options if the flag is set. */ |
| if ((image->flags & PNG_IMAGE_FLAG_FAST) != 0) |
| { |
| png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, PNG_NO_FILTERS); |
| /* NOTE: determined by experiment using pngstest, this reflects some |
| * balance between the time to write the image once and the time to read |
| * it about 50 times. The speed-up in pngstest was about 10-20% of the |
| * total (user) time on a heavily loaded system. |
| */ |
| # ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED |
| png_set_compression_level(png_ptr, 3); |
| # endif |
| } |
| |
| /* Check for the cases that currently require a pre-transform on the row |
| * before it is written. This only applies when the input is 16-bit and |
| * either there is an alpha channel or it is converted to 8-bit. |
| */ |
| if ((linear != 0 && alpha != 0 ) || |
| (colormap == 0 && display->convert_to_8bit != 0)) |
| { |
| png_bytep row = png_voidcast(png_bytep, png_malloc(png_ptr, |
| png_get_rowbytes(png_ptr, info_ptr))); |
| int result; |
| |
| display->local_row = row; |
| if (write_16bit != 0) |
| result = png_safe_execute(image, png_write_image_16bit, display); |
| else |
| result = png_safe_execute(image, png_write_image_8bit, display); |
| display->local_row = NULL; |
| |
| png_free(png_ptr, row); |
| |
| /* Skip the 'write_end' on error: */ |
| if (result == 0) |
| return 0; |
| } |
| |
| /* Otherwise this is the case where the input is in a format currently |
| * supported by the rest of the libpng write code; call it directly. |
| */ |
| else |
| { |
| png_const_bytep row = png_voidcast(png_const_bytep, display->first_row); |
| ptrdiff_t row_bytes = display->row_bytes; |
| png_uint_32 y = image->height; |
| |
| for (; y > 0; --y) |
| { |
| png_write_row(png_ptr, row); |
| row += row_bytes; |
| } |
| } |
| |
| png_write_end(png_ptr, info_ptr); |
| return 1; |
| } |
| |
| |
| static void (PNGCBAPI |
| image_memory_write)(png_structp png_ptr, png_bytep/*const*/ data, size_t size) |
| { |
| png_image_write_control *display = png_voidcast(png_image_write_control*, |
| png_ptr->io_ptr/*backdoor: png_get_io_ptr(png_ptr)*/); |
| png_alloc_size_t ob = display->output_bytes; |
| |
| /* Check for overflow; this should never happen: */ |
| if (size <= ((png_alloc_size_t)-1) - ob) |
| { |
| /* I don't think libpng ever does this, but just in case: */ |
| if (size > 0) |
| { |
| if (display->memory_bytes >= ob+size) /* writing */ |
| memcpy(display->memory+ob, data, size); |
| |
| /* Always update the size: */ |
| display->output_bytes = ob+size; |
| } |
| } |
| |
| else |
| png_error(png_ptr, "png_image_write_to_memory: PNG too big"); |
| } |
| |
| static void (PNGCBAPI |
| image_memory_flush)(png_structp png_ptr) |
| { |
| PNG_UNUSED(png_ptr) |
| } |
| |
| static int |
| png_image_write_memory(png_voidp argument) |
| { |
| png_image_write_control *display = png_voidcast(png_image_write_control*, |
| argument); |
| |
| /* The rest of the memory-specific init and write_main in an error protected |
| * environment. This case needs to use callbacks for the write operations |
| * since libpng has no built in support for writing to memory. |
| */ |
| png_set_write_fn(display->image->opaque->png_ptr, display/*io_ptr*/, |
| image_memory_write, image_memory_flush); |
| |
| return png_image_write_main(display); |
| } |
| |
| int PNGAPI |
| png_image_write_to_memory(png_imagep image, void *memory, |
| png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8bit, |
| const void *buffer, png_int_32 row_stride, const void *colormap) |
| { |
| /* Write the image to the given buffer, or count the bytes if it is NULL */ |
| if (image != NULL && image->version == PNG_IMAGE_VERSION) |
| { |
| if (memory_bytes != NULL && buffer != NULL) |
| { |
| /* This is to give the caller an easier error detection in the NULL |
| * case and guard against uninitialized variable problems: |
| */ |
| if (memory == NULL) |
| *memory_bytes = 0; |
| |
| if (png_image_write_init(image) != 0) |
| { |
| png_image_write_control display; |
| int result; |
| |
| memset(&display, 0, (sizeof display)); |
| display.image = image; |
| display.buffer = buffer; |
| display.row_stride = row_stride; |
| display.colormap = colormap; |
| display.convert_to_8bit = convert_to_8bit; |
| display.memory = png_voidcast(png_bytep, memory); |
| display.memory_bytes = *memory_bytes; |
| display.output_bytes = 0; |
| |
| result = png_safe_execute(image, png_image_write_memory, &display); |
| png_image_free(image); |
| |
| /* write_memory returns true even if we ran out of buffer. */ |
| if (result) |
| { |
| /* On out-of-buffer this function returns '0' but still updates |
| * memory_bytes: |
| */ |
| if (memory != NULL && display.output_bytes > *memory_bytes) |
| result = 0; |
| |
| *memory_bytes = display.output_bytes; |
| } |
| |
| return result; |
| } |
| |
| else |
| return 0; |
| } |
| |
| else |
| return png_image_error(image, |
| "png_image_write_to_memory: invalid argument"); |
| } |
| |
| else if (image != NULL) |
| return png_image_error(image, |
| "png_image_write_to_memory: incorrect PNG_IMAGE_VERSION"); |
| |
| else |
| return 0; |
| } |
| |
| #ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED |
| int PNGAPI |
| png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit, |
| const void *buffer, png_int_32 row_stride, const void *colormap) |
| { |
| /* Write the image to the given (FILE*). */ |
| if (image != NULL && image->version == PNG_IMAGE_VERSION) |
| { |
| if (file != NULL && buffer != NULL) |
| { |
| if (png_image_write_init(image) != 0) |
| { |
| png_image_write_control display; |
| int result; |
| |
| /* This is slightly evil, but png_init_io doesn't do anything other |
| * than this and we haven't changed the standard IO functions so |
| * this saves a 'safe' function. |
| */ |
| image->opaque->png_ptr->io_ptr = file; |
| |
| memset(&display, 0, (sizeof display)); |
| display.image = image; |
| display.buffer = buffer; |
| display.row_stride = row_stride; |
| display.colormap = colormap; |
| display.convert_to_8bit = convert_to_8bit; |
| |
| result = png_safe_execute(image, png_image_write_main, &display); |
| png_image_free(image); |
| return result; |
| } |
| |
| else |
| return 0; |
| } |
| |
| else |
| return png_image_error(image, |
| "png_image_write_to_stdio: invalid argument"); |
| } |
| |
| else if (image != NULL) |
| return png_image_error(image, |
| "png_image_write_to_stdio: incorrect PNG_IMAGE_VERSION"); |
| |
| else |
| return 0; |
| } |
| |
| int PNGAPI |
| png_image_write_to_file(png_imagep image, const char *file_name, |
| int convert_to_8bit, const void *buffer, png_int_32 row_stride, |
| const void *colormap) |
| { |
| /* Write the image to the named file. */ |
| if (image != NULL && image->version == PNG_IMAGE_VERSION) |
| { |
| if (file_name != NULL && buffer != NULL) |
| { |
| FILE *fp = fopen(file_name, "wb"); |
| |
| if (fp != NULL) |
| { |
| if (png_image_write_to_stdio(image, fp, convert_to_8bit, buffer, |
| row_stride, colormap) != 0) |
| { |
| int error; /* from fflush/fclose */ |
| |
| /* Make sure the file is flushed correctly. */ |
| if (fflush(fp) == 0 && ferror(fp) == 0) |
| { |
| if (fclose(fp) == 0) |
| return 1; |
| |
| error = errno; /* from fclose */ |
| } |
| |
| else |
| { |
| error = errno; /* from fflush or ferror */ |
| (void)fclose(fp); |
| } |
| |
| (void)remove(file_name); |
| /* The image has already been cleaned up; this is just used to |
| * set the error (because the original write succeeded). |
| */ |
| return png_image_error(image, strerror(error)); |
| } |
| |
| else |
| { |
| /* Clean up: just the opened file. */ |
| (void)fclose(fp); |
| (void)remove(file_name); |
| return 0; |
| } |
| } |
| |
| else |
| return png_image_error(image, strerror(errno)); |
| } |
| |
| else |
| return png_image_error(image, |
| "png_image_write_to_file: invalid argument"); |
| } |
| |
| else if (image != NULL) |
| return png_image_error(image, |
| "png_image_write_to_file: incorrect PNG_IMAGE_VERSION"); |
| |
| else |
| return 0; |
| } |
| #endif /* SIMPLIFIED_WRITE_STDIO */ |
| #endif /* SIMPLIFIED_WRITE */ |
| #endif /* WRITE */ |