734 lines
22 KiB
C
734 lines
22 KiB
C
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/* pngread.c - read a png file
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libpng 1.0 beta 2 - version 0.81
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For conditions of distribution and use, see copyright notice in png.h
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Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
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August 24, 1995
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*/
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#define PNG_INTERNAL
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#include "png.h"
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/* initialize png structure for reading, and allocate any memory needed */
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void
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png_read_init(png_struct *png_ptr)
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{
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jmp_buf tmp_jmp;
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png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
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png_memset(png_ptr, 0, sizeof (png_struct));
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png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
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png_ptr->zbuf_size = PNG_ZBUF_SIZE;
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png_ptr->zbuf = png_large_malloc(png_ptr, png_ptr->zbuf_size);
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png_ptr->zstream = &(png_ptr->zstream_struct);
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png_ptr->zstream->zalloc = png_zalloc;
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png_ptr->zstream->zfree = png_zfree;
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png_ptr->zstream->opaque = (voidp)png_ptr;
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inflateInit(png_ptr->zstream);
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png_ptr->zstream->next_out = png_ptr->zbuf;
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png_ptr->zstream->avail_out = (uInt)png_ptr->zbuf_size;
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}
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/* read the information before the actual image data. */
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void
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png_read_info(png_struct *png_ptr, png_info *info)
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{
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png_byte chunk_start[8];
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png_uint_32 length;
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(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
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if (memcmp(chunk_start, png_sig, 8))
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(*(png_ptr->error_fn))(png_ptr, "Not a PNG File");
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while (1)
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{
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png_uint_32 crc;
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(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
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length = png_get_uint_32(chunk_start);
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png_reset_crc(png_ptr);
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png_calculate_crc(png_ptr, chunk_start + 4, 4);
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if (!memcmp(chunk_start + 4, png_IHDR, 4))
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{
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if (png_ptr->mode != PNG_BEFORE_IHDR)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place IHDR");
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png_handle_IHDR(png_ptr, info, length);
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png_ptr->mode = PNG_HAVE_IHDR;
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}
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else if (!memcmp(chunk_start + 4, png_PLTE, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR)
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(*(png_ptr->error_fn))(png_ptr, "Missing IHDR");
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#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
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if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
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png_crc_skip(png_ptr, length);
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else
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#else
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{
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png_handle_PLTE(png_ptr, info, length);
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}
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#endif
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png_ptr->mode = PNG_HAVE_PLTE;
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}
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else if (!memcmp(chunk_start + 4, png_IDAT, 4))
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{
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png_ptr->idat_size = length;
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png_ptr->mode = PNG_HAVE_IDAT;
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break;
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}
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else if (!memcmp(chunk_start + 4, png_IEND, 4))
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{
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(*(png_ptr->error_fn))(png_ptr, "No Image in File");
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}
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#if defined(PNG_READ_gAMA_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_gAMA, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place PLTE");
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png_handle_gAMA(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_sBIT_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_sBIT, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place sBIT");
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png_handle_sBIT(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_cHRM_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_cHRM, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place cHRM");
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png_handle_cHRM(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_tRNS_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_tRNS, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR &&
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png_ptr->mode != PNG_HAVE_PLTE)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place tRNS");
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png_handle_tRNS(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_bKGD_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_bKGD, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR &&
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png_ptr->mode != PNG_HAVE_PLTE)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place bKGD");
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png_handle_bKGD(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_hIST_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_hIST, 4))
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{
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if (png_ptr->mode != PNG_HAVE_PLTE)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place hIST");
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png_handle_hIST(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_pHYs_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_pHYs, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR &&
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png_ptr->mode != PNG_HAVE_PLTE)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place pHYs");
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png_handle_pHYs(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_oFFs_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_oFFs, 4))
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{
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if (png_ptr->mode != PNG_HAVE_IHDR &&
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png_ptr->mode != PNG_HAVE_PLTE)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place oFFs");
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png_handle_oFFs(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_tIME_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_tIME, 4))
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{
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if (png_ptr->mode == PNG_BEFORE_IHDR ||
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png_ptr->mode == PNG_AFTER_IEND)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place tIME");
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png_handle_tIME(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_tEXt_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_tEXt, 4))
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{
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if (png_ptr->mode == PNG_BEFORE_IHDR ||
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png_ptr->mode == PNG_AFTER_IEND)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place tEXt");
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png_handle_tEXt(png_ptr, info, length);
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}
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#endif
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#if defined(PNG_READ_zTXt_SUPPORTED)
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else if (!memcmp(chunk_start + 4, png_zTXt, 4))
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{
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if (png_ptr->mode == PNG_BEFORE_IHDR ||
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png_ptr->mode == PNG_AFTER_IEND)
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(*(png_ptr->error_fn))(png_ptr, "Out of Place zTXt");
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png_handle_zTXt(png_ptr, info, length);
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}
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#endif
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else
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{
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if ((chunk_start[4] & 0x20) == 0)
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(*(png_ptr->error_fn))(png_ptr, "Unknown Critical Chunk");
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png_crc_skip(png_ptr, length);
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}
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(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
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crc = png_get_uint_32(chunk_start);
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if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
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(png_ptr->crc & 0xffffffffL))
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(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
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}
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}
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/* optional call to update the users info structure */
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void
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png_read_update_info(png_struct *png_ptr, png_info *info_ptr)
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{
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if (!(png_ptr->row_init))
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png_read_start_row(png_ptr);
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png_read_transform_info(png_ptr, info_ptr);
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}
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/* initialize palette, background, etc, after transformations
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are set, but before any reading takes place. This allows
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the user to obtail a gamma corrected palette, for example.
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If the user doesn't call this, we will do it ourselves. */
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void
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png_start_read_image(png_struct *png_ptr)
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{
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if (!(png_ptr->row_init))
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png_read_start_row(png_ptr);
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}
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void
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png_read_row(png_struct *png_ptr, png_bytef *row, png_byte *dsp_row)
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{
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int ret;
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if (!(png_ptr->row_init))
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png_read_start_row(png_ptr);
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#if defined(PNG_READ_INTERLACING_SUPPORTED)
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/* if interlaced and we do not need a new row, combine row and return */
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if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
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{
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switch (png_ptr->pass)
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{
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case 0:
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if (png_ptr->row_number & 7)
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{
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 1:
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if ((png_ptr->row_number & 7) || png_ptr->width < 5)
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{
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 2:
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if ((png_ptr->row_number & 7) != 4)
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{
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if (dsp_row && (png_ptr->row_number & 4))
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 3:
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if ((png_ptr->row_number & 3) || png_ptr->width < 3)
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{
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 4:
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if ((png_ptr->row_number & 3) != 2)
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{
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if (dsp_row && (png_ptr->row_number & 2))
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 5:
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if ((png_ptr->row_number & 1) || png_ptr->width < 2)
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{
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 6:
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if (!(png_ptr->row_number & 1))
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{
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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}
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}
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#endif
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if (png_ptr->mode != PNG_HAVE_IDAT)
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(*(png_ptr->error_fn))(png_ptr, "Invalid attempt to read row data");
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png_ptr->zstream->next_out = png_ptr->row_buf;
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png_ptr->zstream->avail_out = (uInt)png_ptr->irowbytes;
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do
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{
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if (!(png_ptr->zstream->avail_in))
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{
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while (!png_ptr->idat_size)
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{
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png_byte buf[4];
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png_uint_32 crc;
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(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
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crc = png_get_uint_32(buf);
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if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
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(png_ptr->crc & 0xffffffffL))
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(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
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(*(png_ptr->read_data_fn))(png_ptr, buf, 4);
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png_ptr->idat_size = png_get_uint_32(buf);
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png_reset_crc(png_ptr);
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png_crc_read(png_ptr, buf, 4);
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if (memcmp(buf, png_IDAT, 4))
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(*(png_ptr->error_fn))(png_ptr, "Not enough image data");
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}
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png_ptr->zstream->avail_in = (uInt)png_ptr->zbuf_size;
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png_ptr->zstream->next_in = png_ptr->zbuf;
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if (png_ptr->zbuf_size > png_ptr->idat_size)
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png_ptr->zstream->avail_in = (uInt)png_ptr->idat_size;
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png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream->avail_in);
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png_ptr->idat_size -= png_ptr->zstream->avail_in;
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}
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ret = inflate(png_ptr->zstream, Z_PARTIAL_FLUSH);
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if (ret == Z_STREAM_END)
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{
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if (png_ptr->zstream->avail_out || png_ptr->zstream->avail_in ||
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png_ptr->idat_size)
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(*(png_ptr->warning_fn))(png_ptr, "Extra compressed data");
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png_ptr->mode = PNG_AT_LAST_IDAT;
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break;
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}
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if (ret != Z_OK)
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(*(png_ptr->error_fn))(png_ptr, "Compression Error");
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} while (png_ptr->zstream->avail_out);
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if (ret == Z_STREAM_END)
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png_ptr->zlib_finished = 1;
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png_ptr->row_info.color_type = png_ptr->color_type;
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png_ptr->row_info.width = png_ptr->iwidth;
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png_ptr->row_info.channels = png_ptr->channels;
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png_ptr->row_info.bit_depth = png_ptr->bit_depth;
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png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
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png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
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(png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
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if (png_ptr->row_buf[0])
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png_read_filter_row(&(png_ptr->row_info),
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png_ptr->row_buf + 1, png_ptr->prev_row + 1,
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(int)(png_ptr->row_buf[0]));
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png_memcpy(png_ptr->prev_row, png_ptr->row_buf, (png_size_t)png_ptr->rowbytes + 1);
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if (png_ptr->transformations)
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png_do_read_transformations(png_ptr);
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#if defined(PNG_READ_INTERLACING_SUPPORTED)
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/* blow up interlaced rows to full size */
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if (png_ptr->interlaced &&
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(png_ptr->transformations & PNG_INTERLACE))
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{
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if (png_ptr->pass < 6)
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png_do_read_interlace(&(png_ptr->row_info),
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png_ptr->row_buf + 1, png_ptr->pass);
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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if (row)
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png_combine_row(png_ptr, row,
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png_pass_mask[png_ptr->pass]);
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}
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else
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#endif
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{
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if (row)
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png_combine_row(png_ptr, row, 0xff);
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if (dsp_row)
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png_combine_row(png_ptr, dsp_row, 0xff);
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}
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png_read_finish_row(png_ptr);
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}
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/* read a one or more rows of image data. If the image is interlaced,
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and png_set_interlace_handling() has been called, the rows need to
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to contain the contents of the rows from the previous pass. If
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the image has alpha or transparency, and png_handle_alpha() has been
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called, the rows contents must be initialized to the contents of the
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screen. row holds the actual image, and pixels are placed in it
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as they arrive. If the image is displayed after each pass, it will
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appear to "sparkle" in. display_row can be used to display a
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"chunky" progressive image, with finer detail added as it becomes
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available. If you do not want this "chunky" display, you may pass
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NULL for display_rows. If you do not want the sparkle display, and
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you have not called png_handle_alpha(), you may pass NULL for rows.
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If you have called png_handle_alpha(), and the image has either an
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alpha channel or a transparency chunk, you must provide a buffer for
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rows. In this case, you do not have to provide a display_rows buffer
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also, but you may. If the image is not interlaced, or if you have
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not called png_set_interlace_handling(), the display_row buffer will
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be ignored, so pass NULL to it. */
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void
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png_read_rows(png_struct *png_ptr, png_bytef **row,
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png_byte **display_row, png_uint_32 num_rows)
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{
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png_uint_32 i;
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png_bytef **rp;
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png_byte **dp;
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rp = row;
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dp = display_row;
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for (i = 0; i < num_rows; i++)
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{
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png_bytef *rptr;
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png_byte *dptr;
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if (rp)
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rptr = *rp;
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else
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rptr = NULL;
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if (dp)
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dptr = *dp;
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else
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dptr = NULL;
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png_read_row(png_ptr, rptr, dptr);
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if (row)
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rp++;
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if (display_row)
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dp++;
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}
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}
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|
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/* read the image. If the image has an alpha channel or a transparency
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chunk, and you have called png_handle_alpha(), you will need to
|
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initialize the image to the current image that png will be overlaying.
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Note that png_set_interlace_handling() has no effect on this call.
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You only need to call this function once. If you desire to have
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an image for each pass of a interlaced image, use png_read_rows() */
|
|
void
|
|
png_read_image(png_struct *png_ptr, png_bytef **image)
|
|
{
|
|
png_uint_32 i;
|
|
int pass, j;
|
|
png_bytef **rp;
|
|
|
|
pass = png_set_interlace_handling(png_ptr);
|
|
for (j = 0; j < pass; j++)
|
|
{
|
|
rp = image;
|
|
for (i = 0; i < png_ptr->height; i++)
|
|
{
|
|
png_read_row(png_ptr, *rp, NULL);
|
|
rp++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* read the end of the png file. Will not read past the end of the
|
|
file, will verify the end is accurate, and will read any comments
|
|
or time information at the end of the file, if info is not NULL. */
|
|
void
|
|
png_read_end(png_struct *png_ptr, png_info *info)
|
|
{
|
|
png_byte chunk_start[8];
|
|
png_uint_32 length;
|
|
png_uint_32 crc;
|
|
|
|
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
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|
crc = png_get_uint_32(chunk_start);
|
|
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
|
|
(png_ptr->crc & 0xffffffffL))
|
|
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
|
|
|
|
do
|
|
{
|
|
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 8);
|
|
length = png_get_uint_32(chunk_start);
|
|
png_reset_crc(png_ptr);
|
|
png_calculate_crc(png_ptr, chunk_start + 4, 4);
|
|
|
|
if (!memcmp(chunk_start + 4, png_IHDR, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_PLTE, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_gAMA, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_sBIT, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_cHRM, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_tRNS, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_bKGD, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_hIST, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_IDAT, 4))
|
|
{
|
|
if (length > 0 || png_ptr->mode != PNG_AT_LAST_IDAT)
|
|
(*(png_ptr->error_fn))(png_ptr, "Too many IDAT's found");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_pHYs, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
else if (!memcmp(chunk_start + 4, png_oFFs, 4))
|
|
{
|
|
(*(png_ptr->error_fn))(png_ptr, "Invalid chunk after IDAT");
|
|
}
|
|
#if defined(PNG_READ_tIME_SUPPORTED)
|
|
else if (!memcmp(chunk_start + 4, png_tIME, 4))
|
|
{
|
|
if (png_ptr->mode == PNG_BEFORE_IHDR ||
|
|
png_ptr->mode == PNG_AFTER_IEND)
|
|
(*(png_ptr->error_fn))(png_ptr, "Out of Place tIME");
|
|
|
|
if (info)
|
|
png_handle_tIME(png_ptr, info, length);
|
|
else
|
|
png_crc_skip(png_ptr, length);
|
|
}
|
|
#endif
|
|
#if defined(PNG_READ_tEXt_SUPPORTED)
|
|
else if (!memcmp(chunk_start + 4, png_tEXt, 4))
|
|
{
|
|
if (png_ptr->mode == PNG_BEFORE_IHDR ||
|
|
png_ptr->mode == PNG_AFTER_IEND)
|
|
(*(png_ptr->error_fn))(png_ptr, "Out of Place tEXt");
|
|
|
|
if (info)
|
|
png_handle_tEXt(png_ptr, info, length);
|
|
else
|
|
png_crc_skip(png_ptr, length);
|
|
}
|
|
#endif
|
|
#if defined(PNG_READ_zTXt_SUPPORTED)
|
|
else if (!memcmp(chunk_start + 4, png_zTXt, 4))
|
|
{
|
|
if (png_ptr->mode == PNG_BEFORE_IHDR ||
|
|
png_ptr->mode == PNG_AFTER_IEND)
|
|
(*(png_ptr->error_fn))(png_ptr, "Out of Place zTXt");
|
|
|
|
if (info)
|
|
png_handle_zTXt(png_ptr, info, length);
|
|
else
|
|
png_crc_skip(png_ptr, length);
|
|
}
|
|
#endif
|
|
else if (!memcmp(chunk_start + 4, png_IEND, 4))
|
|
{
|
|
png_ptr->mode = PNG_AFTER_IEND;
|
|
}
|
|
else
|
|
{
|
|
char msg[80];
|
|
|
|
if ((chunk_start[4] & 0x20) == 0)
|
|
{
|
|
png_strcpy(msg,"Unknown critical chunk ");
|
|
png_memcpy(msg + strlen(msg), chunk_start + 4,4);
|
|
(*(png_ptr->error_fn))(png_ptr, msg);
|
|
}
|
|
|
|
png_strcpy(msg,"Unknown extension chunk ");
|
|
png_memcpy(msg + strlen(msg), chunk_start + 4,4);
|
|
(*(png_ptr->warning_fn))(png_ptr, msg);
|
|
png_crc_skip(png_ptr, length);
|
|
}
|
|
(*(png_ptr->read_data_fn))(png_ptr, chunk_start, 4);
|
|
crc = png_get_uint_32(chunk_start);
|
|
if (((crc ^ 0xffffffffL) & 0xffffffffL) !=
|
|
(png_ptr->crc & 0xffffffffL))
|
|
(*(png_ptr->error_fn))(png_ptr, "Bad CRC value");
|
|
if (png_ptr->mode == PNG_AT_LAST_IDAT)
|
|
png_ptr->mode = PNG_AFTER_IDAT;
|
|
} while (png_ptr->mode != PNG_AFTER_IEND);
|
|
}
|
|
|
|
/* free all memory used by the read */
|
|
void
|
|
png_read_destroy(png_struct *png_ptr, png_info *info, png_info *end_info)
|
|
{
|
|
int i;
|
|
jmp_buf tmp_jmp;
|
|
|
|
if (info)
|
|
{
|
|
if (png_ptr->do_free & PNG_FREE_PALETTE)
|
|
png_free(png_ptr, info->palette);
|
|
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED)
|
|
if (png_ptr->do_free & PNG_FREE_TRANS)
|
|
png_free(png_ptr, info->trans);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_hIST_SUPPORTED)
|
|
if (png_ptr->do_free & PNG_FREE_HIST)
|
|
png_free(png_ptr, info->hist);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
|
|
for (i = 0; i < info->num_text; i++)
|
|
{
|
|
png_large_free(png_ptr, info->text[i].key);
|
|
}
|
|
|
|
png_free(png_ptr, info->text);
|
|
#endif
|
|
png_memset(info, 0, sizeof(png_info));
|
|
}
|
|
|
|
if (end_info)
|
|
{
|
|
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
|
|
for (i = 0; i < end_info->num_text; i++)
|
|
{
|
|
png_large_free(png_ptr, end_info->text[i].key);
|
|
}
|
|
|
|
png_free(png_ptr, end_info->text);
|
|
#endif
|
|
png_memset(end_info, 0, sizeof(png_info));
|
|
}
|
|
|
|
png_large_free(png_ptr, png_ptr->zbuf);
|
|
png_large_free(png_ptr, png_ptr->row_buf);
|
|
png_large_free(png_ptr, png_ptr->prev_row);
|
|
|
|
#if defined(PNG_READ_DITHER_SUPPORTED)
|
|
png_large_free(png_ptr, png_ptr->palette_lookup);
|
|
png_free(png_ptr, png_ptr->dither_index);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_GAMMA_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_table);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_from_1);
|
|
png_free(png_ptr, png_ptr->gamma_to_1);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_GAMMA_SUPPORTED)
|
|
if (png_ptr->gamma_16_table)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_table[i]);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_16_table);
|
|
if (png_ptr->gamma_16_from_1)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
|
|
}
|
|
}
|
|
png_free(png_ptr, png_ptr->gamma_16_from_1);
|
|
if (png_ptr->gamma_16_to_1)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
|
|
}
|
|
}
|
|
png_free(png_ptr, png_ptr->gamma_16_to_1);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->trans);
|
|
#endif
|
|
|
|
#if defined(PNG_READ_DITHER_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->hist);
|
|
#endif
|
|
|
|
if (!png_ptr->user_palette)
|
|
png_free(png_ptr, png_ptr->palette);
|
|
|
|
inflateEnd(png_ptr->zstream);
|
|
|
|
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
|
|
png_memset(png_ptr, 0, sizeof (png_struct));
|
|
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
|
|
}
|
|
|