1 2 /* pngstruct.h - header file for PNG reference library 3 * 4 * Copyright (c) 1998-2013 Glenn Randers-Pehrson 5 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) 6 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) 7 * 8 * Last changed in libpng 1.6.1 [March 28, 2013] 9 * 10 * This code is released under the libpng license. 11 * For conditions of distribution and use, see the disclaimer 12 * and license in png.h 13 */ 14 15 /* The structure that holds the information to read and write PNG files. 16 * The only people who need to care about what is inside of this are the 17 * people who will be modifying the library for their own special needs. 18 * It should NOT be accessed directly by an application. 19 */ 20 21 #ifndef PNGSTRUCT_H 22 #define PNGSTRUCT_H 23 /* zlib.h defines the structure z_stream, an instance of which is included 24 * in this structure and is required for decompressing the LZ compressed 25 * data in PNG files. 26 */ 27 #ifndef ZLIB_CONST 28 /* We must ensure that zlib uses 'const' in declarations. */ 29 # define ZLIB_CONST 30 #endif 31 #include "zlib.h" 32 #ifdef const 33 /* zlib.h sometimes #defines const to nothing, undo this. */ 34 # undef const 35 #endif 36 37 /* zlib.h has mediocre z_const use before 1.2.6, this stuff is for compatibility 38 * with older builds. 39 */ 40 #if ZLIB_VERNUM < 0x1260 41 # define PNGZ_MSG_CAST(s) png_constcast(char*,s) 42 # define PNGZ_INPUT_CAST(b) png_constcast(png_bytep,b) 43 #else 44 # define PNGZ_MSG_CAST(s) (s) 45 # define PNGZ_INPUT_CAST(b) (b) 46 #endif 47 48 /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib 49 * can handle at once. This type need be no larger than 16 bits (so maximum of 50 * 65535), this define allows us to discover how big it is, but limited by the 51 * maximuum for png_size_t. The value can be overriden in a library build 52 * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably 53 * lower value (e.g. 255 works). A lower value may help memory usage (slightly) 54 * and may even improve performance on some systems (and degrade it on others.) 55 */ 56 #ifndef ZLIB_IO_MAX 57 # define ZLIB_IO_MAX ((uInt)-1) 58 #endif 59 60 #ifdef PNG_WRITE_SUPPORTED 61 /* The type of a compression buffer list used by the write code. */ 62 typedef struct png_compression_buffer 63 { 64 struct png_compression_buffer *next; 65 png_byte output[1]; /* actually zbuf_size */ 66 } png_compression_buffer, *png_compression_bufferp; 67 68 #define PNG_COMPRESSION_BUFFER_SIZE(pp)\ 69 (offsetof(png_compression_buffer, output) + (pp)->zbuffer_size) 70 #endif 71 72 /* Colorspace support; structures used in png_struct, png_info and in internal 73 * functions to hold and communicate information about the color space. 74 * 75 * PNG_COLORSPACE_SUPPORTED is only required if the application will perform 76 * colorspace corrections, otherwise all the colorspace information can be 77 * skipped and the size of libpng can be reduced (significantly) by compiling 78 * out the colorspace support. 79 */ 80 #ifdef PNG_COLORSPACE_SUPPORTED 81 /* The chromaticities of the red, green and blue colorants and the chromaticity 82 * of the corresponding white point (i.e. of rgb(1.0,1.0,1.0)). 83 */ 84 typedef struct png_xy 85 { 86 png_fixed_point redx, redy; 87 png_fixed_point greenx, greeny; 88 png_fixed_point bluex, bluey; 89 png_fixed_point whitex, whitey; 90 } png_xy; 91 92 /* The same data as above but encoded as CIE XYZ values. When this data comes 93 * from chromaticities the sum of the Y values is assumed to be 1.0 94 */ 95 typedef struct png_XYZ 96 { 97 png_fixed_point red_X, red_Y, red_Z; 98 png_fixed_point green_X, green_Y, green_Z; 99 png_fixed_point blue_X, blue_Y, blue_Z; 100 } png_XYZ; 101 #endif /* COLORSPACE */ 102 103 #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED) 104 /* A colorspace is all the above plus, potentially, profile information, 105 * however at present libpng does not use the profile internally so it is only 106 * stored in the png_info struct (if iCCP is supported.) The rendering intent 107 * is retained here and is checked. 108 * 109 * The file gamma encoding information is also stored here and gamma correction 110 * is done by libpng, whereas color correction must currently be done by the 111 * application. 112 */ 113 typedef struct png_colorspace 114 { 115 #ifdef PNG_GAMMA_SUPPORTED 116 png_fixed_point gamma; /* File gamma */ 117 #endif 118 119 #ifdef PNG_COLORSPACE_SUPPORTED 120 png_xy end_points_xy; /* End points as chromaticities */ 121 png_XYZ end_points_XYZ; /* End points as CIE XYZ colorant values */ 122 png_uint_16 rendering_intent; /* Rendering intent of a profile */ 123 #endif 124 125 /* Flags are always defined to simplify the code. */ 126 png_uint_16 flags; /* As defined below */ 127 } png_colorspace, * PNG_RESTRICT png_colorspacerp; 128 129 typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp; 130 131 /* General flags for the 'flags' field */ 132 #define PNG_COLORSPACE_HAVE_GAMMA 0x0001 133 #define PNG_COLORSPACE_HAVE_ENDPOINTS 0x0002 134 #define PNG_COLORSPACE_HAVE_INTENT 0x0004 135 #define PNG_COLORSPACE_FROM_gAMA 0x0008 136 #define PNG_COLORSPACE_FROM_cHRM 0x0010 137 #define PNG_COLORSPACE_FROM_sRGB 0x0020 138 #define PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB 0x0040 139 #define PNG_COLORSPACE_MATCHES_sRGB 0x0080 /* exact match on profile */ 140 #define PNG_COLORSPACE_INVALID 0x8000 141 #define PNG_COLORSPACE_CANCEL(flags) (0xffff ^ (flags)) 142 #endif /* COLORSPACE || GAMMA */ 143 144 #ifdef PNG_INDEX_SUPPORTED 145 /* png_line_index_struct records an index point, where we impose an index point 146 * to be located at the beginning of a line for simplifying the implementation. 147 */ 148 typedef struct png_line_index_struct 149 { 150 // state of the lz decoder 151 z_streamp z_state; 152 153 // the IDAT header position of the chunk, which the index point is in 154 png_uint_32 stream_idat_position; 155 156 // we intend to record the offset of the index point in the chunk, 157 // but we record the number of remaining bytes in the chunk after the 158 // index point. That's because PNG processes a chunk this way. 159 png_uint_32 bytes_left_in_idat; 160 161 // decompressed data of the previous row 162 png_bytep prev_row; 163 } png_line_index; 164 typedef png_line_index FAR * png_line_indexp; 165 166 typedef struct png_index_struct 167 { 168 // A temporary variable used when we build the index. The variable records 169 // the IDAT header position of the last chunk read in so far. 170 png_uint_32 stream_idat_position; 171 172 // line index information about each passes 173 174 // the number of index points in each pass 175 png_uint_32 size[7]; 176 177 // the line span of two index points of each pass 178 png_uint_32 step[7]; 179 180 // the index points of each pass 181 png_line_indexp *pass_line_index[7]; 182 } png_index; 183 typedef png_index FAR * png_indexp; 184 185 #define INDEX_SAMPLE_SIZE 254 186 #endif 187 188 struct png_struct_def 189 { 190 #ifdef PNG_SETJMP_SUPPORTED 191 jmp_buf jmp_buf_local; /* New name in 1.6.0 for jmp_buf in png_struct */ 192 png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */ 193 jmp_buf *jmp_buf_ptr; /* passed to longjmp_fn */ 194 size_t jmp_buf_size; /* size of the above, if allocated */ 195 #endif 196 png_error_ptr error_fn; /* function for printing errors and aborting */ 197 #ifdef PNG_WARNINGS_SUPPORTED 198 png_error_ptr warning_fn; /* function for printing warnings */ 199 #endif 200 png_voidp error_ptr; /* user supplied struct for error functions */ 201 png_rw_ptr write_data_fn; /* function for writing output data */ 202 png_rw_ptr read_data_fn; /* function for reading input data */ 203 #ifdef PNG_INDEX_SUPPORTED 204 png_seek_ptr seek_data_fn; /* function for seeking input data */ 205 #endif 206 png_voidp io_ptr; /* ptr to application struct for I/O functions */ 207 208 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED 209 png_user_transform_ptr read_user_transform_fn; /* user read transform */ 210 #endif 211 212 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED 213 png_user_transform_ptr write_user_transform_fn; /* user write transform */ 214 #endif 215 216 /* These were added in libpng-1.0.2 */ 217 #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED 218 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ 219 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) 220 png_voidp user_transform_ptr; /* user supplied struct for user transform */ 221 png_byte user_transform_depth; /* bit depth of user transformed pixels */ 222 png_byte user_transform_channels; /* channels in user transformed pixels */ 223 #endif 224 #endif 225 226 png_uint_32 mode; /* tells us where we are in the PNG file */ 227 png_uint_32 flags; /* flags indicating various things to libpng */ 228 png_uint_32 transformations; /* which transformations to perform */ 229 230 png_uint_32 zowner; /* ID (chunk type) of zstream owner, 0 if none */ 231 z_stream zstream; /* decompression structure */ 232 233 #ifdef PNG_WRITE_SUPPORTED 234 png_compression_bufferp zbuffer_list; /* Created on demand during write */ 235 uInt zbuffer_size; /* size of the actual buffer */ 236 237 int zlib_level; /* holds zlib compression level */ 238 int zlib_method; /* holds zlib compression method */ 239 int zlib_window_bits; /* holds zlib compression window bits */ 240 int zlib_mem_level; /* holds zlib compression memory level */ 241 int zlib_strategy; /* holds zlib compression strategy */ 242 #endif 243 /* Added at libpng 1.5.4 */ 244 #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED 245 int zlib_text_level; /* holds zlib compression level */ 246 int zlib_text_method; /* holds zlib compression method */ 247 int zlib_text_window_bits; /* holds zlib compression window bits */ 248 int zlib_text_mem_level; /* holds zlib compression memory level */ 249 int zlib_text_strategy; /* holds zlib compression strategy */ 250 #endif 251 /* End of material added at libpng 1.5.4 */ 252 /* Added at libpng 1.6.0 */ 253 #ifdef PNG_WRITE_SUPPORTED 254 int zlib_set_level; /* Actual values set into the zstream on write */ 255 int zlib_set_method; 256 int zlib_set_window_bits; 257 int zlib_set_mem_level; 258 int zlib_set_strategy; 259 #endif 260 261 png_uint_32 width; /* width of image in pixels */ 262 png_uint_32 height; /* height of image in pixels */ 263 png_uint_32 num_rows; /* number of rows in current pass */ 264 png_uint_32 usr_width; /* width of row at start of write */ 265 png_size_t rowbytes; /* size of row in bytes */ 266 png_uint_32 iwidth; /* width of current interlaced row in pixels */ 267 png_uint_32 row_number; /* current row in interlace pass */ 268 png_uint_32 chunk_name; /* PNG_CHUNK() id of current chunk */ 269 png_bytep prev_row; /* buffer to save previous (unfiltered) row. 270 * This is a pointer into big_prev_row 271 */ 272 png_bytep row_buf; /* buffer to save current (unfiltered) row. 273 * This is a pointer into big_row_buf 274 */ 275 #ifdef PNG_WRITE_SUPPORTED 276 png_bytep sub_row; /* buffer to save "sub" row when filtering */ 277 png_bytep up_row; /* buffer to save "up" row when filtering */ 278 png_bytep avg_row; /* buffer to save "avg" row when filtering */ 279 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */ 280 #endif 281 png_size_t info_rowbytes; /* Added in 1.5.4: cache of updated row bytes */ 282 283 png_uint_32 idat_size; /* current IDAT size for read */ 284 png_uint_32 crc; /* current chunk CRC value */ 285 png_colorp palette; /* palette from the input file */ 286 png_uint_16 num_palette; /* number of color entries in palette */ 287 288 /* Added at libpng-1.5.10 */ 289 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED 290 int num_palette_max; /* maximum palette index found in IDAT */ 291 #endif 292 293 png_uint_16 num_trans; /* number of transparency values */ 294 png_byte compression; /* file compression type (always 0) */ 295 png_byte filter; /* file filter type (always 0) */ 296 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */ 297 png_byte pass; /* current interlace pass (0 - 6) */ 298 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */ 299 png_byte color_type; /* color type of file */ 300 png_byte bit_depth; /* bit depth of file */ 301 png_byte usr_bit_depth; /* bit depth of users row: write only */ 302 png_byte pixel_depth; /* number of bits per pixel */ 303 png_byte channels; /* number of channels in file */ 304 #ifdef PNG_WRITE_SUPPORTED 305 png_byte usr_channels; /* channels at start of write: write only */ 306 #endif 307 png_byte sig_bytes; /* magic bytes read/written from start of file */ 308 png_byte maximum_pixel_depth; 309 /* pixel depth used for the row buffers */ 310 png_byte transformed_pixel_depth; 311 /* pixel depth after read/write transforms */ 312 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) 313 png_uint_16 filler; /* filler bytes for pixel expansion */ 314 #endif 315 316 #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\ 317 defined(PNG_READ_ALPHA_MODE_SUPPORTED) 318 png_byte background_gamma_type; 319 png_fixed_point background_gamma; 320 png_color_16 background; /* background color in screen gamma space */ 321 #ifdef PNG_READ_GAMMA_SUPPORTED 322 png_color_16 background_1; /* background normalized to gamma 1.0 */ 323 #endif 324 #endif /* PNG_bKGD_SUPPORTED */ 325 326 #ifdef PNG_WRITE_FLUSH_SUPPORTED 327 png_flush_ptr output_flush_fn; /* Function for flushing output */ 328 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */ 329 png_uint_32 flush_rows; /* number of rows written since last flush */ 330 #endif 331 332 #ifdef PNG_READ_GAMMA_SUPPORTED 333 int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */ 334 png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */ 335 336 png_bytep gamma_table; /* gamma table for 8-bit depth files */ 337 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */ 338 #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ 339 defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \ 340 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) 341 png_bytep gamma_from_1; /* converts from 1.0 to screen */ 342 png_bytep gamma_to_1; /* converts from file to 1.0 */ 343 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */ 344 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */ 345 #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */ 346 #endif 347 348 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED) 349 png_color_8 sig_bit; /* significant bits in each available channel */ 350 #endif 351 352 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) 353 png_color_8 shift; /* shift for significant bit tranformation */ 354 #endif 355 356 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \ 357 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) 358 png_bytep trans_alpha; /* alpha values for paletted files */ 359 png_color_16 trans_color; /* transparent color for non-paletted files */ 360 #endif 361 362 png_read_status_ptr read_row_fn; /* called after each row is decoded */ 363 png_write_status_ptr write_row_fn; /* called after each row is encoded */ 364 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED 365 png_progressive_info_ptr info_fn; /* called after header data fully read */ 366 png_progressive_row_ptr row_fn; /* called after a prog. row is decoded */ 367 png_progressive_end_ptr end_fn; /* called after image is complete */ 368 png_bytep save_buffer_ptr; /* current location in save_buffer */ 369 png_bytep save_buffer; /* buffer for previously read data */ 370 png_bytep current_buffer_ptr; /* current location in current_buffer */ 371 png_bytep current_buffer; /* buffer for recently used data */ 372 png_uint_32 push_length; /* size of current input chunk */ 373 png_uint_32 skip_length; /* bytes to skip in input data */ 374 png_size_t save_buffer_size; /* amount of data now in save_buffer */ 375 png_size_t save_buffer_max; /* total size of save_buffer */ 376 png_size_t buffer_size; /* total amount of available input data */ 377 png_size_t current_buffer_size; /* amount of data now in current_buffer */ 378 int process_mode; /* what push library is currently doing */ 379 int cur_palette; /* current push library palette index */ 380 381 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ 382 383 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__) 384 /* For the Borland special 64K segment handler */ 385 png_bytepp offset_table_ptr; 386 png_bytep offset_table; 387 png_uint_16 offset_table_number; 388 png_uint_16 offset_table_count; 389 png_uint_16 offset_table_count_free; 390 #endif 391 392 #ifdef PNG_READ_QUANTIZE_SUPPORTED 393 png_bytep palette_lookup; /* lookup table for quantizing */ 394 png_bytep quantize_index; /* index translation for palette files */ 395 #endif 396 397 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED 398 png_byte heuristic_method; /* heuristic for row filter selection */ 399 png_byte num_prev_filters; /* number of weights for previous rows */ 400 png_bytep prev_filters; /* filter type(s) of previous row(s) */ 401 png_uint_16p filter_weights; /* weight(s) for previous line(s) */ 402 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */ 403 png_uint_16p filter_costs; /* relative filter calculation cost */ 404 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */ 405 #endif 406 407 /* Options */ 408 #ifdef PNG_SET_OPTION_SUPPORTED 409 png_byte options; /* On/off state (up to 4 options) */ 410 #endif 411 412 #if PNG_LIBPNG_VER < 10700 413 /* To do: remove this from libpng-1.7 */ 414 #ifdef PNG_TIME_RFC1123_SUPPORTED 415 char time_buffer[29]; /* String to hold RFC 1123 time text */ 416 #endif 417 #endif 418 419 /* New members added in libpng-1.0.6 */ 420 421 png_uint_32 free_me; /* flags items libpng is responsible for freeing */ 422 423 #ifdef PNG_USER_CHUNKS_SUPPORTED 424 png_voidp user_chunk_ptr; 425 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED 426 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */ 427 #endif 428 #endif 429 430 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED 431 int unknown_default; /* As PNG_HANDLE_* */ 432 unsigned int num_chunk_list; /* Number of entries in the list */ 433 png_bytep chunk_list; /* List of png_byte[5]; the textual chunk name 434 * followed by a PNG_HANDLE_* byte */ 435 #endif 436 437 /* New members added in libpng-1.0.3 */ 438 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED 439 png_byte rgb_to_gray_status; 440 /* Added in libpng 1.5.5 to record setting of coefficients: */ 441 png_byte rgb_to_gray_coefficients_set; 442 /* These were changed from png_byte in libpng-1.0.6 */ 443 png_uint_16 rgb_to_gray_red_coeff; 444 png_uint_16 rgb_to_gray_green_coeff; 445 /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */ 446 #endif 447 448 /* New member added in libpng-1.0.4 (renamed in 1.0.9) */ 449 #if defined(PNG_MNG_FEATURES_SUPPORTED) 450 /* Changed from png_byte to png_uint_32 at version 1.2.0 */ 451 png_uint_32 mng_features_permitted; 452 #endif 453 454 /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */ 455 #ifdef PNG_MNG_FEATURES_SUPPORTED 456 png_byte filter_type; 457 #endif 458 459 /* New members added in libpng-1.2.0 */ 460 461 /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */ 462 #ifdef PNG_USER_MEM_SUPPORTED 463 png_voidp mem_ptr; /* user supplied struct for mem functions */ 464 png_malloc_ptr malloc_fn; /* function for allocating memory */ 465 png_free_ptr free_fn; /* function for freeing memory */ 466 #endif 467 468 /* New member added in libpng-1.0.13 and 1.2.0 */ 469 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */ 470 471 #ifdef PNG_READ_QUANTIZE_SUPPORTED 472 /* The following three members were added at version 1.0.14 and 1.2.4 */ 473 png_bytep quantize_sort; /* working sort array */ 474 png_bytep index_to_palette; /* where the original index currently is 475 in the palette */ 476 png_bytep palette_to_index; /* which original index points to this 477 palette color */ 478 #endif 479 480 /* New members added in libpng-1.0.16 and 1.2.6 */ 481 png_byte compression_type; 482 483 #ifdef PNG_USER_LIMITS_SUPPORTED 484 png_uint_32 user_width_max; 485 png_uint_32 user_height_max; 486 487 /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown 488 * chunks that can be stored (0 means unlimited). 489 */ 490 png_uint_32 user_chunk_cache_max; 491 492 /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk 493 * can occupy when decompressed. 0 means unlimited. 494 */ 495 png_alloc_size_t user_chunk_malloc_max; 496 #endif 497 498 /* New member added in libpng-1.0.25 and 1.2.17 */ 499 #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED 500 /* Temporary storage for unknown chunk that the library doesn't recognize, 501 * used while reading the chunk. 502 */ 503 png_unknown_chunk unknown_chunk; 504 #endif 505 506 /* New member added in libpng-1.2.26 */ 507 png_size_t old_big_row_buf_size; 508 509 #ifdef PNG_READ_SUPPORTED 510 /* New member added in libpng-1.2.30 */ 511 png_bytep read_buffer; /* buffer for reading chunk data */ 512 png_alloc_size_t read_buffer_size; /* current size of the buffer */ 513 #endif 514 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 515 uInt IDAT_read_size; /* limit on read buffer size for IDAT */ 516 #endif 517 518 #ifdef PNG_IO_STATE_SUPPORTED 519 /* New member added in libpng-1.4.0 */ 520 png_uint_32 io_state; 521 #endif 522 523 /* New member added in libpng-1.5.6 */ 524 png_bytep big_prev_row; 525 526 /* New member added in libpng-1.5.7 */ 527 void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info, 528 png_bytep row, png_const_bytep prev_row); 529 530 #ifdef PNG_READ_SUPPORTED 531 #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED) 532 png_colorspace colorspace; 533 #endif 534 #endif 535 536 #ifdef PNG_INDEX_SUPPORTED 537 png_indexp index; 538 png_uint_32 total_data_read; 539 #endif 540 541 }; 542 #endif /* PNGSTRUCT_H */ 543