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2396 lines
75 KiB
C
2396 lines
75 KiB
C
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/* pngwrite.c - general routines to write a PNG file
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*
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* Copyright (c) 2018-2019 Cosmin Truta
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* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
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* Copyright (c) 1996-1997 Andreas Dilger
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* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
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*
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* This code is released under the libpng license.
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* For conditions of distribution and use, see the disclaimer
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* and license in png.h
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*/
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#include "pngpriv.h"
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#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
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# include <errno.h>
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#endif /* SIMPLIFIED_WRITE_STDIO */
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#ifdef PNG_WRITE_SUPPORTED
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#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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/* Write out all the unknown chunks for the current given location */
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static void
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write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
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unsigned int where)
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{
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if (info_ptr->unknown_chunks_num != 0)
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{
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png_const_unknown_chunkp up;
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png_debug(5, "writing extra chunks");
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for (up = info_ptr->unknown_chunks;
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up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
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++up)
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if ((up->location & where) != 0)
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{
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/* If per-chunk unknown chunk handling is enabled use it, otherwise
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* just write the chunks the application has set.
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*/
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#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
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int keep = png_handle_as_unknown(png_ptr, up->name);
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/* NOTE: this code is radically different from the read side in the
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* matter of handling an ancillary unknown chunk. In the read side
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* the default behavior is to discard it, in the code below the default
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* behavior is to write it. Critical chunks are, however, only
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* written if explicitly listed or if the default is set to write all
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* unknown chunks.
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*
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* The default handling is also slightly weird - it is not possible to
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* stop the writing of all unsafe-to-copy chunks!
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*
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* TODO: REVIEW: this would seem to be a bug.
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*/
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if (keep != PNG_HANDLE_CHUNK_NEVER &&
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((up->name[3] & 0x20) /* safe-to-copy overrides everything */ ||
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keep == PNG_HANDLE_CHUNK_ALWAYS ||
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(keep == PNG_HANDLE_CHUNK_AS_DEFAULT &&
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png_ptr->unknown_default == PNG_HANDLE_CHUNK_ALWAYS)))
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#endif
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{
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/* TODO: review, what is wrong with a zero length unknown chunk? */
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if (up->size == 0)
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png_warning(png_ptr, "Writing zero-length unknown chunk");
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png_write_chunk(png_ptr, up->name, up->data, up->size);
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}
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}
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}
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}
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#endif /* WRITE_UNKNOWN_CHUNKS */
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/* Writes all the PNG information. This is the suggested way to use the
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* library. If you have a new chunk to add, make a function to write it,
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* and put it in the correct location here. If you want the chunk written
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* after the image data, put it in png_write_end(). I strongly encourage
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* you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
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* the chunk, as that will keep the code from breaking if you want to just
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* write a plain PNG file. If you have long comments, I suggest writing
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* them in png_write_end(), and compressing them.
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*/
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void PNGAPI
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png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
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{
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png_debug(1, "in png_write_info_before_PLTE");
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if (png_ptr == NULL || info_ptr == NULL)
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return;
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if ((png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE) == 0)
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{
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/* Write PNG signature */
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png_write_sig(png_ptr);
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#ifdef PNG_MNG_FEATURES_SUPPORTED
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if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0 && \
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png_ptr->mng_features_permitted != 0)
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{
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png_warning(png_ptr,
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"MNG features are not allowed in a PNG datastream");
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png_ptr->mng_features_permitted = 0;
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}
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#endif
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/* Write IHDR information. */
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png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
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info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
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info_ptr->filter_type,
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#ifdef PNG_WRITE_INTERLACING_SUPPORTED
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info_ptr->interlace_type
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#else
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0
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#endif
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);
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/* The rest of these check to see if the valid field has the appropriate
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* flag set, and if it does, writes the chunk.
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*
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* 1.6.0: COLORSPACE support controls the writing of these chunks too, and
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* the chunks will be written if the WRITE routine is there and
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* information * is available in the COLORSPACE. (See
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* png_colorspace_sync_info in png.c for where the valid flags get set.)
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*
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* Under certain circumstances the colorspace can be invalidated without
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* syncing the info_struct 'valid' flags; this happens if libpng detects
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* an error and calls png_error while the color space is being set, yet
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* the application continues writing the PNG. So check the 'invalid'
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* flag here too.
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*/
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#ifdef PNG_GAMMA_SUPPORTED
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# ifdef PNG_WRITE_gAMA_SUPPORTED
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if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
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(info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) != 0 &&
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(info_ptr->valid & PNG_INFO_gAMA) != 0)
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png_write_gAMA_fixed(png_ptr, info_ptr->colorspace.gamma);
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# endif
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#endif
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#ifdef PNG_COLORSPACE_SUPPORTED
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/* Write only one of sRGB or an ICC profile. If a profile was supplied
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* and it matches one of the known sRGB ones issue a warning.
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*/
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# ifdef PNG_WRITE_iCCP_SUPPORTED
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if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
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(info_ptr->valid & PNG_INFO_iCCP) != 0)
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{
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# ifdef PNG_WRITE_sRGB_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_sRGB) != 0)
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png_app_warning(png_ptr,
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"profile matches sRGB but writing iCCP instead");
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# endif
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png_write_iCCP(png_ptr, info_ptr->iccp_name,
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info_ptr->iccp_profile);
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}
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# ifdef PNG_WRITE_sRGB_SUPPORTED
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else
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# endif
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# endif
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# ifdef PNG_WRITE_sRGB_SUPPORTED
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if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
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(info_ptr->valid & PNG_INFO_sRGB) != 0)
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png_write_sRGB(png_ptr, info_ptr->colorspace.rendering_intent);
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# endif /* WRITE_sRGB */
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#endif /* COLORSPACE */
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#ifdef PNG_WRITE_sBIT_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
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png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
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#endif
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#ifdef PNG_COLORSPACE_SUPPORTED
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# ifdef PNG_WRITE_cHRM_SUPPORTED
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if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
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(info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) != 0 &&
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(info_ptr->valid & PNG_INFO_cHRM) != 0)
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png_write_cHRM_fixed(png_ptr, &info_ptr->colorspace.end_points_xy);
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# endif
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#endif
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#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_IHDR);
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#endif
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png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
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}
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}
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void PNGAPI
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png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
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{
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#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
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int i;
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#endif
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png_debug(1, "in png_write_info");
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if (png_ptr == NULL || info_ptr == NULL)
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return;
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png_write_info_before_PLTE(png_ptr, info_ptr);
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if ((info_ptr->valid & PNG_INFO_PLTE) != 0)
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png_write_PLTE(png_ptr, info_ptr->palette,
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(png_uint_32)info_ptr->num_palette);
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else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
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png_error(png_ptr, "Valid palette required for paletted images");
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#ifdef PNG_WRITE_tRNS_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_tRNS) !=0)
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{
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#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
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/* Invert the alpha channel (in tRNS) */
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if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0 &&
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info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
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{
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int j, jend;
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jend = info_ptr->num_trans;
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if (jend > PNG_MAX_PALETTE_LENGTH)
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jend = PNG_MAX_PALETTE_LENGTH;
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for (j = 0; j<jend; ++j)
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info_ptr->trans_alpha[j] =
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(png_byte)(255 - info_ptr->trans_alpha[j]);
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}
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#endif
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png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),
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info_ptr->num_trans, info_ptr->color_type);
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}
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#endif
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#ifdef PNG_WRITE_bKGD_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_bKGD) != 0)
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png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
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#endif
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#ifdef PNG_WRITE_eXIf_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_eXIf) != 0)
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png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif);
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#endif
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#ifdef PNG_WRITE_hIST_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_hIST) != 0)
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png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
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#endif
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#ifdef PNG_WRITE_oFFs_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_oFFs) != 0)
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png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
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info_ptr->offset_unit_type);
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#endif
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#ifdef PNG_WRITE_pCAL_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_pCAL) != 0)
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png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
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info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
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info_ptr->pcal_units, info_ptr->pcal_params);
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#endif
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#ifdef PNG_WRITE_sCAL_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_sCAL) != 0)
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png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
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info_ptr->scal_s_width, info_ptr->scal_s_height);
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#endif /* sCAL */
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#ifdef PNG_WRITE_pHYs_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_pHYs) != 0)
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png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
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info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
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#endif /* pHYs */
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#ifdef PNG_WRITE_tIME_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_tIME) != 0)
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{
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png_write_tIME(png_ptr, &(info_ptr->mod_time));
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png_ptr->mode |= PNG_WROTE_tIME;
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}
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#endif /* tIME */
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#ifdef PNG_WRITE_sPLT_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_sPLT) != 0)
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for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
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png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
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#endif /* sPLT */
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#ifdef PNG_WRITE_TEXT_SUPPORTED
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/* Check to see if we need to write text chunks */
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for (i = 0; i < info_ptr->num_text; i++)
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{
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png_debug2(2, "Writing header text chunk %d, type %d", i,
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info_ptr->text[i].compression);
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/* An internationalized chunk? */
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if (info_ptr->text[i].compression > 0)
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{
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#ifdef PNG_WRITE_iTXt_SUPPORTED
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/* Write international chunk */
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png_write_iTXt(png_ptr,
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info_ptr->text[i].compression,
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info_ptr->text[i].key,
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info_ptr->text[i].lang,
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info_ptr->text[i].lang_key,
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info_ptr->text[i].text);
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/* Mark this chunk as written */
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if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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else
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
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#else
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png_warning(png_ptr, "Unable to write international text");
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#endif
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}
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/* If we want a compressed text chunk */
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else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
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{
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#ifdef PNG_WRITE_zTXt_SUPPORTED
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/* Write compressed chunk */
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png_write_zTXt(png_ptr, info_ptr->text[i].key,
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info_ptr->text[i].text, info_ptr->text[i].compression);
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/* Mark this chunk as written */
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
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#else
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png_warning(png_ptr, "Unable to write compressed text");
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#endif
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}
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else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
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{
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#ifdef PNG_WRITE_tEXt_SUPPORTED
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/* Write uncompressed chunk */
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png_write_tEXt(png_ptr, info_ptr->text[i].key,
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info_ptr->text[i].text,
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0);
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/* Mark this chunk as written */
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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#else
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/* Can't get here */
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png_warning(png_ptr, "Unable to write uncompressed text");
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#endif
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}
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}
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#endif /* tEXt */
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#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_PLTE);
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#endif
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}
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/* Writes the end of the PNG file. If you don't want to write comments or
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* time information, you can pass NULL for info. If you already wrote these
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* in png_write_info(), do not write them again here. If you have long
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* comments, I suggest writing them here, and compressing them.
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*/
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void PNGAPI
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png_write_end(png_structrp png_ptr, png_inforp info_ptr)
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{
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png_debug(1, "in png_write_end");
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if (png_ptr == NULL)
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return;
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if ((png_ptr->mode & PNG_HAVE_IDAT) == 0)
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png_error(png_ptr, "No IDATs written into file");
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#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
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if (png_ptr->num_palette_max > png_ptr->num_palette)
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png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
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#endif
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/* See if user wants us to write information chunks */
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if (info_ptr != NULL)
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{
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#ifdef PNG_WRITE_TEXT_SUPPORTED
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int i; /* local index variable */
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#endif
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#ifdef PNG_WRITE_tIME_SUPPORTED
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/* Check to see if user has supplied a time chunk */
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if ((info_ptr->valid & PNG_INFO_tIME) != 0 &&
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(png_ptr->mode & PNG_WROTE_tIME) == 0)
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png_write_tIME(png_ptr, &(info_ptr->mod_time));
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#endif
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#ifdef PNG_WRITE_TEXT_SUPPORTED
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/* Loop through comment chunks */
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for (i = 0; i < info_ptr->num_text; i++)
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{
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png_debug2(2, "Writing trailer text chunk %d, type %d", i,
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info_ptr->text[i].compression);
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/* An internationalized chunk? */
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if (info_ptr->text[i].compression > 0)
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{
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#ifdef PNG_WRITE_iTXt_SUPPORTED
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/* Write international chunk */
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png_write_iTXt(png_ptr,
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info_ptr->text[i].compression,
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info_ptr->text[i].key,
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info_ptr->text[i].lang,
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info_ptr->text[i].lang_key,
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info_ptr->text[i].text);
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/* Mark this chunk as written */
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if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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else
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
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#else
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png_warning(png_ptr, "Unable to write international text");
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#endif
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}
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else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
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{
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#ifdef PNG_WRITE_zTXt_SUPPORTED
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/* Write compressed chunk */
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png_write_zTXt(png_ptr, info_ptr->text[i].key,
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info_ptr->text[i].text, info_ptr->text[i].compression);
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/* Mark this chunk as written */
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
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#else
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png_warning(png_ptr, "Unable to write compressed text");
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#endif
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}
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else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
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{
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#ifdef PNG_WRITE_tEXt_SUPPORTED
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/* Write uncompressed chunk */
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png_write_tEXt(png_ptr, info_ptr->text[i].key,
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info_ptr->text[i].text, 0);
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/* Mark this chunk as written */
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info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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#else
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png_warning(png_ptr, "Unable to write uncompressed text");
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#endif
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}
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}
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#endif
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#ifdef PNG_WRITE_eXIf_SUPPORTED
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if ((info_ptr->valid & PNG_INFO_eXIf) != 0)
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png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif);
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#endif
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#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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write_unknown_chunks(png_ptr, info_ptr, PNG_AFTER_IDAT);
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#endif
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}
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png_ptr->mode |= PNG_AFTER_IDAT;
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|
|
/* 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);
|
|
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 */
|