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789 lines
26 KiB
789 lines
26 KiB
|
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/* pngread.c - read a PNG file |
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* |
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* libpng 1.0.1 |
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* For conditions of distribution and use, see copyright notice in png.h |
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* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
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* Copyright (c) 1996, 1997 Andreas Dilger |
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* Copyright (c) 1998, Glenn Randers-Pehrson |
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* March 9, 1998 |
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* |
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* This file contains routines that an application calls directly to |
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* read a PNG file or stream. |
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*/ |
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|
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#define PNG_INTERNAL |
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#include "png.h" |
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|
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/* Create a PNG structure for reading, and allocate any memory needed. */ |
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png_structp |
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png_create_read_struct(png_const_charp user_png_ver, voidp error_ptr, |
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png_error_ptr error_fn, png_error_ptr warn_fn) |
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{ |
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png_structp png_ptr; |
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#ifdef USE_FAR_KEYWORD |
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jmp_buf jmpbuf; |
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#endif |
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png_debug(1, "in png_create_read_struct\n"); |
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if ((png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG)) == NULL) |
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{ |
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return (png_structp)NULL; |
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} |
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#ifdef USE_FAR_KEYWORD |
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if (setjmp(jmpbuf)) |
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#else |
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if (setjmp(png_ptr->jmpbuf)) |
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#endif |
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{ |
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png_free(png_ptr, png_ptr->zbuf); |
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png_destroy_struct(png_ptr); |
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return (png_structp)NULL; |
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} |
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#ifdef USE_FAR_KEYWORD |
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png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf)); |
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#endif |
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png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); |
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|
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/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so |
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* we must recompile any applications that use any older library version. |
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* For versions after libpng 1.0, we will be compatible, so we need |
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* only check the first digit. |
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*/ |
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if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || |
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(user_png_ver[0] == '0' && user_png_ver[2] < '9')) |
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{ |
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png_error(png_ptr, |
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"Incompatible libpng version in application and library"); |
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} |
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|
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/* initialize zbuf - compression buffer */ |
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png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
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png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
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(png_uint_32)png_ptr->zbuf_size); |
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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 = (voidpf)png_ptr; |
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|
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switch (inflateInit(&png_ptr->zstream)) |
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{ |
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case Z_OK: /* Do nothing */ break; |
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case Z_MEM_ERROR: |
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case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break; |
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case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break; |
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default: png_error(png_ptr, "Unknown zlib error"); |
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} |
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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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png_set_read_fn(png_ptr, NULL, NULL); |
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|
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return (png_ptr); |
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} |
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|
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/* Initialize PNG structure for reading, and allocate any memory needed. |
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This interface is depreciated in favour of the png_create_read_struct(), |
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and it will eventually disappear. */ |
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void |
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png_read_init(png_structp png_ptr) |
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{ |
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jmp_buf tmp_jmp; /* to save current jump buffer */ |
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|
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png_debug(1, "in png_read_init\n"); |
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/* save jump buffer and error functions */ |
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png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); |
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|
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/* reset all variables to 0 */ |
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png_memset(png_ptr, 0, sizeof (png_struct)); |
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|
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/* restore jump buffer */ |
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png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); |
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|
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/* initialize zbuf - compression buffer */ |
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png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
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png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
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(png_uint_32)png_ptr->zbuf_size); |
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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 = (voidpf)png_ptr; |
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|
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switch (inflateInit(&png_ptr->zstream)) |
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{ |
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case Z_OK: /* Do nothing */ break; |
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case Z_MEM_ERROR: |
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case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break; |
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case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break; |
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default: png_error(png_ptr, "Unknown zlib error"); |
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} |
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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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png_set_read_fn(png_ptr, NULL, NULL); |
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} |
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|
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/* Read the information before the actual image data. This has been |
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* changed in v0.90 to allow reading a file which already has the magic |
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* bytes read from the stream. You can tell libpng how many bytes have |
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* been read from the beginning of the stream (up to the maxumum of 8) |
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* via png_set_sig_bytes(), and we will only check the remaining bytes |
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* here. The application can then have access to the signature bytes we |
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* read if it is determined that this isn't a valid PNG file. |
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*/ |
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void |
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png_read_info(png_structp png_ptr, png_infop info_ptr) |
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{ |
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png_debug(1, "in png_read_info\n"); |
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/* save jump buffer and error functions */ |
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/* If we haven't checked all of the PNG signature bytes, do so now. */ |
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if (png_ptr->sig_bytes < 8) |
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{ |
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png_size_t num_checked = png_ptr->sig_bytes, |
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num_to_check = 8 - num_checked; |
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|
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png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); |
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png_ptr->sig_bytes = 8; |
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|
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if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) |
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{ |
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if (num_checked < 4 && |
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png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) |
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png_error(png_ptr, "Not a PNG file"); |
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else |
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png_error(png_ptr, "PNG file corrupted by ASCII conversion"); |
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} |
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} |
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|
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for(;;) |
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{ |
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png_byte chunk_length[4]; |
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png_uint_32 length; |
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|
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png_read_data(png_ptr, chunk_length, 4); |
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length = png_get_uint_32(chunk_length); |
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png_reset_crc(png_ptr); |
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png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
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png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name); |
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|
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/* This should be a binary subdivision search or a hash for |
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* matching the chunk name rather than a linear search. |
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*/ |
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if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) |
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png_handle_IHDR(png_ptr, info_ptr, length); |
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else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
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png_handle_PLTE(png_ptr, info_ptr, length); |
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else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) |
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png_handle_IEND(png_ptr, info_ptr, length); |
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else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
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{ |
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if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
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png_error(png_ptr, "Missing IHDR before IDAT"); |
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else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
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!(png_ptr->mode & PNG_HAVE_PLTE)) |
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png_error(png_ptr, "Missing PLTE before IDAT"); |
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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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#if defined(PNG_READ_bKGD_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) |
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png_handle_bKGD(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_cHRM_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) |
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png_handle_cHRM(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_gAMA_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) |
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png_handle_gAMA(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_hIST_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) |
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png_handle_hIST(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_oFFs_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) |
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png_handle_oFFs(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_pCAL_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) |
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png_handle_pCAL(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_pHYs_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) |
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png_handle_pHYs(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_sBIT_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) |
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png_handle_sBIT(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_sRGB_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) |
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png_handle_sRGB(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_tEXt_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) |
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png_handle_tEXt(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_tIME_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) |
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png_handle_tIME(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_tRNS_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) |
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png_handle_tRNS(png_ptr, info_ptr, length); |
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#endif |
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#if defined(PNG_READ_zTXt_SUPPORTED) |
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else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) |
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png_handle_zTXt(png_ptr, info_ptr, length); |
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#endif |
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else |
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png_handle_unknown(png_ptr, info_ptr, length); |
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} |
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} |
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|
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/* optional call to update the users info_ptr structure */ |
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void |
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png_read_update_info(png_structp png_ptr, png_infop info_ptr) |
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{ |
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png_debug(1, "in png_read_update_info\n"); |
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/* save jump buffer and error functions */ |
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if (!(png_ptr->flags & PNG_FLAG_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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|
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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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*/ |
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void |
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png_start_read_image(png_structp png_ptr) |
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{ |
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png_debug(1, "in png_start_read_image\n"); |
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/* save jump buffer and error functions */ |
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if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
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png_read_start_row(png_ptr); |
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} |
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|
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void |
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png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) |
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{ |
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int ret; |
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png_debug2(1, "in png_read_row (row %d, pass %d)\n", |
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png_ptr->row_number, png_ptr->pass); |
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/* save jump buffer and error functions */ |
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if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
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png_read_start_row(png_ptr); |
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|
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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 != NULL) |
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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 != NULL) |
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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 != NULL && (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 != NULL) |
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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 != NULL && (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 != NULL) |
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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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|
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if (!(png_ptr->mode & PNG_HAVE_IDAT)) |
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png_error(png_ptr, "Invalid attempt to read row data"); |
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|
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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 chunk_length[4]; |
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|
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png_crc_finish(png_ptr, 0); |
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|
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png_read_data(png_ptr, chunk_length, 4); |
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png_ptr->idat_size = png_get_uint_32(chunk_length); |
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|
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png_reset_crc(png_ptr); |
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png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
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if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
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png_error(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, |
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(png_size_t)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_error(png_ptr, "Extra compressed data"); |
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png_ptr->mode |= PNG_AFTER_IDAT; |
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png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
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break; |
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} |
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if (ret != Z_OK) |
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png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : |
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"Decompression error"); |
|
|
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} while (png_ptr->zstream.avail_out); |
|
|
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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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{ |
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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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} |
|
|
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png_read_filter_row(png_ptr, &(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_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, |
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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) |
|
/* blow up interlaced rows to full size */ |
|
if (png_ptr->interlaced && |
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(png_ptr->transformations & PNG_INTERLACE)) |
|
{ |
|
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, png_ptr->transformations); |
|
|
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if (dsp_row != NULL) |
|
png_combine_row(png_ptr, dsp_row, |
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png_pass_dsp_mask[png_ptr->pass]); |
|
if (row != NULL) |
|
png_combine_row(png_ptr, row, |
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png_pass_mask[png_ptr->pass]); |
|
} |
|
else |
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#endif |
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{ |
|
if (row != NULL) |
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png_combine_row(png_ptr, row, 0xff); |
|
if (dsp_row != NULL) |
|
png_combine_row(png_ptr, dsp_row, 0xff); |
|
} |
|
png_read_finish_row(png_ptr); |
|
|
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if (png_ptr->read_row_fn != NULL) |
|
(*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); |
|
} |
|
|
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/* Read 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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* contain the contents of the rows from the previous pass. If the |
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* 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. |
|
* |
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* "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 |
|
* 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 |
|
* NULL for display_row. 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. |
|
* 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_row buffer |
|
* also, but you may. If the image is not interlaced, or if you have |
|
* not called png_set_interlace_handling(), the display_row buffer will |
|
* be ignored, so pass NULL to it. |
|
*/ |
|
|
|
void |
|
png_read_rows(png_structp png_ptr, png_bytepp row, |
|
png_bytepp display_row, png_uint_32 num_rows) |
|
{ |
|
png_uint_32 i; |
|
png_bytepp rp; |
|
png_bytepp dp; |
|
|
|
png_debug(1, "in png_read_rows\n"); |
|
/* save jump buffer and error functions */ |
|
rp = row; |
|
dp = display_row; |
|
for (i = 0; i < num_rows; i++) |
|
{ |
|
png_bytep rptr; |
|
png_bytep dptr; |
|
|
|
if (rp != NULL) |
|
rptr = *rp; |
|
else |
|
rptr = NULL; |
|
if (dp != NULL) |
|
dptr = *dp; |
|
else |
|
dptr = NULL; |
|
png_read_row(png_ptr, rptr, dptr); |
|
if (row != NULL) |
|
rp++; |
|
if (display_row != NULL) |
|
dp++; |
|
} |
|
} |
|
|
|
/* Read the entire image. If the image has an alpha channel or a tRNS |
|
* chunk, and you have called png_handle_alpha(), you will need to |
|
* initialize the image to the current image that PNG will be overlaying. |
|
* We set the num_rows again here, in case it was incorrectly set in |
|
* png_read_start_row() by a call to png_read_update_info() or |
|
* png_start_read_image() if png_set_interlace_handling() wasn't called |
|
* prior to either of these functions like it should have been. You can |
|
* only call this function once. If you desire to have an image for |
|
* each pass of a interlaced image, use png_read_rows() instead. |
|
*/ |
|
void |
|
png_read_image(png_structp png_ptr, png_bytepp image) |
|
{ |
|
png_uint_32 i; |
|
int pass, j; |
|
png_bytepp rp; |
|
|
|
png_debug(1, "in png_read_image\n"); |
|
/* save jump buffer and error functions */ |
|
pass = png_set_interlace_handling(png_ptr); |
|
|
|
png_ptr->num_rows = png_ptr->height; /* Make sure this is set correctly */ |
|
|
|
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_structp png_ptr, png_infop info_ptr) |
|
{ |
|
png_byte chunk_length[4]; |
|
png_uint_32 length; |
|
|
|
png_debug(1, "in png_read_end\n"); |
|
/* save jump buffer and error functions */ |
|
png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ |
|
|
|
do |
|
{ |
|
png_read_data(png_ptr, chunk_length, 4); |
|
length = png_get_uint_32(chunk_length); |
|
|
|
png_reset_crc(png_ptr); |
|
png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
|
|
|
png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name); |
|
|
|
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) |
|
png_handle_IHDR(png_ptr, info_ptr, length); |
|
else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
|
{ |
|
/* Zero length IDATs are legal after the last IDAT has been |
|
* read, but not after other chunks have been read. |
|
*/ |
|
if (length > 0 || png_ptr->mode & PNG_AFTER_IDAT) |
|
png_error(png_ptr, "Too many IDAT's found"); |
|
else |
|
png_crc_finish(png_ptr, 0); |
|
} |
|
else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
|
png_handle_PLTE(png_ptr, info_ptr, length); |
|
else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) |
|
png_handle_IEND(png_ptr, info_ptr, length); |
|
#if defined(PNG_READ_bKGD_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) |
|
png_handle_bKGD(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_cHRM_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) |
|
png_handle_cHRM(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_gAMA_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) |
|
png_handle_gAMA(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_hIST_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) |
|
png_handle_hIST(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_oFFs_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) |
|
png_handle_oFFs(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_pCAL_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) |
|
png_handle_pCAL(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_pHYs_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) |
|
png_handle_pHYs(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_sBIT_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) |
|
png_handle_sBIT(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_sRGB_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) |
|
png_handle_sRGB(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_tEXt_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) |
|
png_handle_tEXt(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_tIME_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) |
|
png_handle_tIME(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_tRNS_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) |
|
png_handle_tRNS(png_ptr, info_ptr, length); |
|
#endif |
|
#if defined(PNG_READ_zTXt_SUPPORTED) |
|
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) |
|
png_handle_zTXt(png_ptr, info_ptr, length); |
|
#endif |
|
else |
|
png_handle_unknown(png_ptr, info_ptr, length); |
|
} while (!(png_ptr->mode & PNG_HAVE_IEND)); |
|
} |
|
|
|
/* free all memory used by the read */ |
|
void |
|
png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, |
|
png_infopp end_info_ptr_ptr) |
|
{ |
|
png_structp png_ptr = NULL; |
|
png_infop info_ptr = NULL, end_info_ptr = NULL; |
|
|
|
png_debug(1, "in png_destroy_read_struct\n"); |
|
/* save jump buffer and error functions */ |
|
if (png_ptr_ptr != NULL) |
|
png_ptr = *png_ptr_ptr; |
|
|
|
if (info_ptr_ptr != NULL) |
|
info_ptr = *info_ptr_ptr; |
|
|
|
if (end_info_ptr_ptr != NULL) |
|
end_info_ptr = *end_info_ptr_ptr; |
|
|
|
png_read_destroy(png_ptr, info_ptr, end_info_ptr); |
|
|
|
if (info_ptr != NULL) |
|
{ |
|
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED) |
|
png_free(png_ptr, info_ptr->text); |
|
#endif |
|
png_destroy_struct((png_voidp)info_ptr); |
|
*info_ptr_ptr = (png_infop)NULL; |
|
} |
|
|
|
if (end_info_ptr != NULL) |
|
{ |
|
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED) |
|
png_free(png_ptr, end_info_ptr->text); |
|
#endif |
|
png_destroy_struct((png_voidp)end_info_ptr); |
|
*end_info_ptr_ptr = (png_infop)NULL; |
|
} |
|
|
|
if (png_ptr != NULL) |
|
{ |
|
png_destroy_struct((png_voidp)png_ptr); |
|
*png_ptr_ptr = (png_structp)NULL; |
|
} |
|
} |
|
|
|
/* free all memory used by the read (old method) */ |
|
void |
|
png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr) |
|
{ |
|
jmp_buf tmp_jmp; |
|
png_error_ptr error_fn; |
|
png_error_ptr warning_fn; |
|
png_voidp error_ptr; |
|
|
|
png_debug(1, "in png_read_destroy\n"); |
|
/* save jump buffer and error functions */ |
|
if (info_ptr != NULL) |
|
png_info_destroy(png_ptr, info_ptr); |
|
|
|
if (end_info_ptr != NULL) |
|
png_info_destroy(png_ptr, end_info_ptr); |
|
|
|
png_free(png_ptr, png_ptr->zbuf); |
|
png_free(png_ptr, png_ptr->row_buf); |
|
png_free(png_ptr, png_ptr->prev_row); |
|
#if defined(PNG_READ_DITHER_SUPPORTED) |
|
png_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 (png_ptr->flags & PNG_FLAG_FREE_PALETTE) |
|
png_zfree(png_ptr, png_ptr->palette); |
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED) |
|
if (png_ptr->flags & PNG_FLAG_FREE_TRANS) |
|
png_free(png_ptr, png_ptr->trans); |
|
#endif |
|
#if defined(PNG_READ_hIST_SUPPORTED) |
|
if (png_ptr->flags & PNG_FLAG_FREE_HIST) |
|
png_free(png_ptr, png_ptr->hist); |
|
#endif |
|
#if defined(PNG_READ_GAMMA_SUPPORTED) |
|
if (png_ptr->gamma_16_table != NULL) |
|
{ |
|
int i; |
|
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 != NULL) |
|
{ |
|
int i; |
|
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 != NULL) |
|
{ |
|
int i; |
|
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 |
|
|
|
inflateEnd(&png_ptr->zstream); |
|
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
png_free(png_ptr, png_ptr->save_buffer); |
|
#endif |
|
|
|
/* Save the important info out of the png_struct, in case it is |
|
* being used again. |
|
*/ |
|
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf)); |
|
|
|
error_fn = png_ptr->error_fn; |
|
warning_fn = png_ptr->warning_fn; |
|
error_ptr = png_ptr->error_ptr; |
|
|
|
png_memset(png_ptr, 0, sizeof (png_struct)); |
|
|
|
png_ptr->error_fn = error_fn; |
|
png_ptr->warning_fn = warning_fn; |
|
png_ptr->error_ptr = error_ptr; |
|
|
|
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf)); |
|
} |
|
|
|
void |
|
png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) |
|
{ |
|
png_ptr->read_row_fn = read_row_fn; |
|
}
|
|
|