| 1 | |
| 2 | /* pngread.c - read a PNG file |
| 3 | * |
| 4 | * Last changed in libpng 1.2.19 August 19, 2007 |
| 5 | * For conditions of distribution and use, see copyright notice in png.h |
| 6 | * Copyright (c) 1998-2007 Glenn Randers-Pehrson |
| 7 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
| 8 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
| 9 | * |
| 10 | * This file contains routines that an application calls directly to |
| 11 | * read a PNG file or stream. |
| 12 | */ |
| 13 | |
| 14 | #define PNG_INTERNAL |
| 15 | #include "png.h" |
| 16 | |
| 17 | #if defined(PNG_READ_SUPPORTED) |
| 18 | |
| 19 | /* Create a PNG structure for reading, and allocate any memory needed. */ |
| 20 | png_structp PNGAPI |
| 21 | png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr, |
| 22 | png_error_ptr error_fn, png_error_ptr warn_fn) |
| 23 | { |
| 24 | |
| 25 | #ifdef PNG_USER_MEM_SUPPORTED |
| 26 | return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, |
| 27 | warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL)); |
| 28 | } |
| 29 | |
| 30 | /* Alternate create PNG structure for reading, and allocate any memory needed. */ |
| 31 | png_structp PNGAPI |
| 32 | png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, |
| 33 | png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, |
| 34 | png_malloc_ptr malloc_fn, png_free_ptr free_fn) |
| 35 | { |
| 36 | #endif /* PNG_USER_MEM_SUPPORTED */ |
| 37 | |
| 38 | png_structp png_ptr; |
| 39 | |
| 40 | #ifdef PNG_SETJMP_SUPPORTED |
| 41 | #ifdef USE_FAR_KEYWORD |
| 42 | jmp_buf jmpbuf; |
| 43 | #endif |
| 44 | #endif |
| 45 | |
| 46 | int i; |
| 47 | |
| 48 | png_debug(1, "in png_create_read_struct\n"); |
| 49 | #ifdef PNG_USER_MEM_SUPPORTED |
| 50 | png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, |
| 51 | (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); |
| 52 | #else |
| 53 | png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
| 54 | #endif |
| 55 | if (png_ptr == NULL) |
| 56 | return (NULL); |
| 57 | |
| 58 | /* added at libpng-1.2.6 */ |
| 59 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
| 60 | png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
| 61 | png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
| 62 | #endif |
| 63 | |
| 64 | #ifdef PNG_SETJMP_SUPPORTED |
| 65 | #ifdef USE_FAR_KEYWORD |
| 66 | if (setjmp(jmpbuf)) |
| 67 | #else |
| 68 | if (setjmp(png_ptr->jmpbuf)) |
| 69 | #endif |
| 70 | { |
| 71 | png_free(png_ptr, png_ptr->zbuf); |
| 72 | png_ptr->zbuf=NULL; |
| 73 | #ifdef PNG_USER_MEM_SUPPORTED |
| 74 | png_destroy_struct_2((png_voidp)png_ptr, |
| 75 | (png_free_ptr)free_fn, (png_voidp)mem_ptr); |
| 76 | #else |
| 77 | png_destroy_struct((png_voidp)png_ptr); |
| 78 | #endif |
| 79 | return (NULL); |
| 80 | } |
| 81 | #ifdef USE_FAR_KEYWORD |
| 82 | png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf)); |
| 83 | #endif |
| 84 | #endif |
| 85 | |
| 86 | #ifdef PNG_USER_MEM_SUPPORTED |
| 87 | png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); |
| 88 | #endif |
| 89 | |
| 90 | png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); |
| 91 | |
| 92 | i=0; |
| 93 | do |
| 94 | { |
| 95 | if(user_png_ver[i] != png_libpng_ver[i]) |
| 96 | png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
| 97 | } while (png_libpng_ver[i++]); |
| 98 | |
| 99 | if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) |
| 100 | { |
| 101 | /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so |
| 102 | * we must recompile any applications that use any older library version. |
| 103 | * For versions after libpng 1.0, we will be compatible, so we need |
| 104 | * only check the first digit. |
| 105 | */ |
| 106 | if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || |
| 107 | (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || |
| 108 | (user_png_ver[0] == '0' && user_png_ver[2] < '9')) |
| 109 | { |
| 110 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
| 111 | char msg[80]; |
| 112 | if (user_png_ver) |
| 113 | { |
| 114 | png_snprintf(msg, 80, |
| 115 | "Application was compiled with png.h from libpng-%.20s", |
| 116 | user_png_ver); |
| 117 | png_warning(png_ptr, msg); |
| 118 | } |
| 119 | png_snprintf(msg, 80, |
| 120 | "Application is running with png.c from libpng-%.20s", |
| 121 | png_libpng_ver); |
| 122 | png_warning(png_ptr, msg); |
| 123 | #endif |
| 124 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
| 125 | png_ptr->flags=0; |
| 126 | #endif |
| 127 | png_error(png_ptr, |
| 128 | "Incompatible libpng version in application and library"); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | /* initialize zbuf - compression buffer */ |
| 133 | png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
| 134 | png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
| 135 | (png_uint_32)png_ptr->zbuf_size); |
| 136 | png_ptr->zstream.zalloc = png_zalloc; |
| 137 | png_ptr->zstream.zfree = png_zfree; |
| 138 | png_ptr->zstream.opaque = (voidpf)png_ptr; |
| 139 | |
| 140 | switch (inflateInit(&png_ptr->zstream)) |
| 141 | { |
| 142 | case Z_OK: /* Do nothing */ break; |
| 143 | case Z_MEM_ERROR: |
| 144 | case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break; |
| 145 | case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break; |
| 146 | default: png_error(png_ptr, "Unknown zlib error"); |
| 147 | } |
| 148 | |
| 149 | png_ptr->zstream.next_out = png_ptr->zbuf; |
| 150 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
| 151 | |
| 152 | png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
| 153 | |
| 154 | #ifdef PNG_SETJMP_SUPPORTED |
| 155 | /* Applications that neglect to set up their own setjmp() and then encounter |
| 156 | a png_error() will longjmp here. Since the jmpbuf is then meaningless we |
| 157 | abort instead of returning. */ |
| 158 | #ifdef USE_FAR_KEYWORD |
| 159 | if (setjmp(jmpbuf)) |
| 160 | PNG_ABORT(); |
| 161 | png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf)); |
| 162 | #else |
| 163 | if (setjmp(png_ptr->jmpbuf)) |
| 164 | PNG_ABORT(); |
| 165 | #endif |
| 166 | #endif |
| 167 | return (png_ptr); |
| 168 | } |
| 169 | |
| 170 | #if defined(PNG_1_0_X) || defined(PNG_1_2_X) |
| 171 | /* Initialize PNG structure for reading, and allocate any memory needed. |
| 172 | This interface is deprecated in favour of the png_create_read_struct(), |
| 173 | and it will disappear as of libpng-1.3.0. */ |
| 174 | #undef png_read_init |
| 175 | void PNGAPI |
| 176 | png_read_init(png_structp png_ptr) |
| 177 | { |
| 178 | /* We only come here via pre-1.0.7-compiled applications */ |
| 179 | png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0); |
| 180 | } |
| 181 | |
| 182 | void PNGAPI |
| 183 | png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver, |
| 184 | png_size_t png_struct_size, png_size_t png_info_size) |
| 185 | { |
| 186 | /* We only come here via pre-1.0.12-compiled applications */ |
| 187 | if(png_ptr == NULL) return; |
| 188 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
| 189 | if(png_sizeof(png_struct) > png_struct_size || |
| 190 | png_sizeof(png_info) > png_info_size) |
| 191 | { |
| 192 | char msg[80]; |
| 193 | png_ptr->warning_fn=NULL; |
| 194 | if (user_png_ver) |
| 195 | { |
| 196 | png_snprintf(msg, 80, |
| 197 | "Application was compiled with png.h from libpng-%.20s", |
| 198 | user_png_ver); |
| 199 | png_warning(png_ptr, msg); |
| 200 | } |
| 201 | png_snprintf(msg, 80, |
| 202 | "Application is running with png.c from libpng-%.20s", |
| 203 | png_libpng_ver); |
| 204 | png_warning(png_ptr, msg); |
| 205 | } |
| 206 | #endif |
| 207 | if(png_sizeof(png_struct) > png_struct_size) |
| 208 | { |
| 209 | png_ptr->error_fn=NULL; |
| 210 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
| 211 | png_ptr->flags=0; |
| 212 | #endif |
| 213 | png_error(png_ptr, |
| 214 | "The png struct allocated by the application for reading is too small."); |
| 215 | } |
| 216 | if(png_sizeof(png_info) > png_info_size) |
| 217 | { |
| 218 | png_ptr->error_fn=NULL; |
| 219 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
| 220 | png_ptr->flags=0; |
| 221 | #endif |
| 222 | png_error(png_ptr, |
| 223 | "The info struct allocated by application for reading is too small."); |
| 224 | } |
| 225 | png_read_init_3(&png_ptr, user_png_ver, png_struct_size); |
| 226 | } |
| 227 | #endif /* PNG_1_0_X || PNG_1_2_X */ |
| 228 | |
| 229 | void PNGAPI |
| 230 | png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver, |
| 231 | png_size_t png_struct_size) |
| 232 | { |
| 233 | #ifdef PNG_SETJMP_SUPPORTED |
| 234 | jmp_buf tmp_jmp; /* to save current jump buffer */ |
| 235 | #endif |
| 236 | |
| 237 | int i=0; |
| 238 | |
| 239 | png_structp png_ptr=*ptr_ptr; |
| 240 | |
| 241 | if(png_ptr == NULL) return; |
| 242 | |
| 243 | do |
| 244 | { |
| 245 | if(user_png_ver[i] != png_libpng_ver[i]) |
| 246 | { |
| 247 | #ifdef PNG_LEGACY_SUPPORTED |
| 248 | png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
| 249 | #else |
| 250 | png_ptr->warning_fn=NULL; |
| 251 | png_warning(png_ptr, |
| 252 | "Application uses deprecated png_read_init() and should be recompiled."); |
| 253 | break; |
| 254 | #endif |
| 255 | } |
| 256 | } while (png_libpng_ver[i++]); |
| 257 | |
| 258 | png_debug(1, "in png_read_init_3\n"); |
| 259 | |
| 260 | #ifdef PNG_SETJMP_SUPPORTED |
| 261 | /* save jump buffer and error functions */ |
| 262 | png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf)); |
| 263 | #endif |
| 264 | |
| 265 | if(png_sizeof(png_struct) > png_struct_size) |
| 266 | { |
| 267 | png_destroy_struct(png_ptr); |
| 268 | *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
| 269 | png_ptr = *ptr_ptr; |
| 270 | } |
| 271 | |
| 272 | /* reset all variables to 0 */ |
| 273 | png_memset(png_ptr, 0, png_sizeof (png_struct)); |
| 274 | |
| 275 | #ifdef PNG_SETJMP_SUPPORTED |
| 276 | /* restore jump buffer */ |
| 277 | png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf)); |
| 278 | #endif |
| 279 | |
| 280 | /* added at libpng-1.2.6 */ |
| 281 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
| 282 | png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
| 283 | png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
| 284 | #endif |
| 285 | |
| 286 | /* initialize zbuf - compression buffer */ |
| 287 | png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
| 288 | png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
| 289 | (png_uint_32)png_ptr->zbuf_size); |
| 290 | png_ptr->zstream.zalloc = png_zalloc; |
| 291 | png_ptr->zstream.zfree = png_zfree; |
| 292 | png_ptr->zstream.opaque = (voidpf)png_ptr; |
| 293 | |
| 294 | switch (inflateInit(&png_ptr->zstream)) |
| 295 | { |
| 296 | case Z_OK: /* Do nothing */ break; |
| 297 | case Z_MEM_ERROR: |
| 298 | case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break; |
| 299 | case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break; |
| 300 | default: png_error(png_ptr, "Unknown zlib error"); |
| 301 | } |
| 302 | |
| 303 | png_ptr->zstream.next_out = png_ptr->zbuf; |
| 304 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
| 305 | |
| 306 | png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
| 307 | } |
| 308 | |
| 309 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 310 | /* Read the information before the actual image data. This has been |
| 311 | * changed in v0.90 to allow reading a file that already has the magic |
| 312 | * bytes read from the stream. You can tell libpng how many bytes have |
| 313 | * been read from the beginning of the stream (up to the maximum of 8) |
| 314 | * via png_set_sig_bytes(), and we will only check the remaining bytes |
| 315 | * here. The application can then have access to the signature bytes we |
| 316 | * read if it is determined that this isn't a valid PNG file. |
| 317 | */ |
| 318 | void PNGAPI |
| 319 | png_read_info(png_structp png_ptr, png_infop info_ptr) |
| 320 | { |
| 321 | if(png_ptr == NULL) return; |
| 322 | png_debug(1, "in png_read_info\n"); |
| 323 | /* If we haven't checked all of the PNG signature bytes, do so now. */ |
| 324 | if (png_ptr->sig_bytes < 8) |
| 325 | { |
| 326 | png_size_t num_checked = png_ptr->sig_bytes, |
| 327 | num_to_check = 8 - num_checked; |
| 328 | |
| 329 | png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); |
| 330 | png_ptr->sig_bytes = 8; |
| 331 | |
| 332 | if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) |
| 333 | { |
| 334 | if (num_checked < 4 && |
| 335 | png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) |
| 336 | png_error(png_ptr, "Not a PNG file"); |
| 337 | else |
| 338 | png_error(png_ptr, "PNG file corrupted by ASCII conversion"); |
| 339 | } |
| 340 | if (num_checked < 3) |
| 341 | png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; |
| 342 | } |
| 343 | |
| 344 | for(;;) |
| 345 | { |
| 346 | #ifdef PNG_USE_LOCAL_ARRAYS |
| 347 | PNG_CONST PNG_IHDR; |
| 348 | PNG_CONST PNG_IDAT; |
| 349 | PNG_CONST PNG_IEND; |
| 350 | PNG_CONST PNG_PLTE; |
| 351 | #if defined(PNG_READ_bKGD_SUPPORTED) |
| 352 | PNG_CONST PNG_bKGD; |
| 353 | #endif |
| 354 | #if defined(PNG_READ_cHRM_SUPPORTED) |
| 355 | PNG_CONST PNG_cHRM; |
| 356 | #endif |
| 357 | #if defined(PNG_READ_gAMA_SUPPORTED) |
| 358 | PNG_CONST PNG_gAMA; |
| 359 | #endif |
| 360 | #if defined(PNG_READ_hIST_SUPPORTED) |
| 361 | PNG_CONST PNG_hIST; |
| 362 | #endif |
| 363 | #if defined(PNG_READ_iCCP_SUPPORTED) |
| 364 | PNG_CONST PNG_iCCP; |
| 365 | #endif |
| 366 | #if defined(PNG_READ_iTXt_SUPPORTED) |
| 367 | PNG_CONST PNG_iTXt; |
| 368 | #endif |
| 369 | #if defined(PNG_READ_oFFs_SUPPORTED) |
| 370 | PNG_CONST PNG_oFFs; |
| 371 | #endif |
| 372 | #if defined(PNG_READ_pCAL_SUPPORTED) |
| 373 | PNG_CONST PNG_pCAL; |
| 374 | #endif |
| 375 | #if defined(PNG_READ_pHYs_SUPPORTED) |
| 376 | PNG_CONST PNG_pHYs; |
| 377 | #endif |
| 378 | #if defined(PNG_READ_sBIT_SUPPORTED) |
| 379 | PNG_CONST PNG_sBIT; |
| 380 | #endif |
| 381 | #if defined(PNG_READ_sCAL_SUPPORTED) |
| 382 | PNG_CONST PNG_sCAL; |
| 383 | #endif |
| 384 | #if defined(PNG_READ_sPLT_SUPPORTED) |
| 385 | PNG_CONST PNG_sPLT; |
| 386 | #endif |
| 387 | #if defined(PNG_READ_sRGB_SUPPORTED) |
| 388 | PNG_CONST PNG_sRGB; |
| 389 | #endif |
| 390 | #if defined(PNG_READ_tEXt_SUPPORTED) |
| 391 | PNG_CONST PNG_tEXt; |
| 392 | #endif |
| 393 | #if defined(PNG_READ_tIME_SUPPORTED) |
| 394 | PNG_CONST PNG_tIME; |
| 395 | #endif |
| 396 | #if defined(PNG_READ_tRNS_SUPPORTED) |
| 397 | PNG_CONST PNG_tRNS; |
| 398 | #endif |
| 399 | #if defined(PNG_READ_zTXt_SUPPORTED) |
| 400 | PNG_CONST PNG_zTXt; |
| 401 | #endif |
| 402 | #endif /* PNG_USE_LOCAL_ARRAYS */ |
| 403 | png_byte chunk_length[4]; |
| 404 | png_uint_32 length; |
| 405 | |
| 406 | png_read_data(png_ptr, chunk_length, 4); |
| 407 | length = png_get_uint_31(png_ptr,chunk_length); |
| 408 | |
| 409 | png_reset_crc(png_ptr); |
| 410 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
| 411 | |
| 412 | png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name, |
| 413 | length); |
| 414 | |
| 415 | /* This should be a binary subdivision search or a hash for |
| 416 | * matching the chunk name rather than a linear search. |
| 417 | */ |
| 418 | if (!png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4)) |
| 419 | if(png_ptr->mode & PNG_AFTER_IDAT) |
| 420 | png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; |
| 421 | |
| 422 | if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) |
| 423 | png_handle_IHDR(png_ptr, info_ptr, length); |
| 424 | else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) |
| 425 | png_handle_IEND(png_ptr, info_ptr, length); |
| 426 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
| 427 | else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) |
| 428 | { |
| 429 | if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 430 | png_ptr->mode |= PNG_HAVE_IDAT; |
| 431 | png_handle_unknown(png_ptr, info_ptr, length); |
| 432 | if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
| 433 | png_ptr->mode |= PNG_HAVE_PLTE; |
| 434 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 435 | { |
| 436 | if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
| 437 | png_error(png_ptr, "Missing IHDR before IDAT"); |
| 438 | else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
| 439 | !(png_ptr->mode & PNG_HAVE_PLTE)) |
| 440 | png_error(png_ptr, "Missing PLTE before IDAT"); |
| 441 | break; |
| 442 | } |
| 443 | } |
| 444 | #endif |
| 445 | else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
| 446 | png_handle_PLTE(png_ptr, info_ptr, length); |
| 447 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 448 | { |
| 449 | if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
| 450 | png_error(png_ptr, "Missing IHDR before IDAT"); |
| 451 | else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
| 452 | !(png_ptr->mode & PNG_HAVE_PLTE)) |
| 453 | png_error(png_ptr, "Missing PLTE before IDAT"); |
| 454 | |
| 455 | png_ptr->idat_size = length; |
| 456 | png_ptr->mode |= PNG_HAVE_IDAT; |
| 457 | break; |
| 458 | } |
| 459 | #if defined(PNG_READ_bKGD_SUPPORTED) |
| 460 | else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) |
| 461 | png_handle_bKGD(png_ptr, info_ptr, length); |
| 462 | #endif |
| 463 | #if defined(PNG_READ_cHRM_SUPPORTED) |
| 464 | else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) |
| 465 | png_handle_cHRM(png_ptr, info_ptr, length); |
| 466 | #endif |
| 467 | #if defined(PNG_READ_gAMA_SUPPORTED) |
| 468 | else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) |
| 469 | png_handle_gAMA(png_ptr, info_ptr, length); |
| 470 | #endif |
| 471 | #if defined(PNG_READ_hIST_SUPPORTED) |
| 472 | else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) |
| 473 | png_handle_hIST(png_ptr, info_ptr, length); |
| 474 | #endif |
| 475 | #if defined(PNG_READ_oFFs_SUPPORTED) |
| 476 | else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) |
| 477 | png_handle_oFFs(png_ptr, info_ptr, length); |
| 478 | #endif |
| 479 | #if defined(PNG_READ_pCAL_SUPPORTED) |
| 480 | else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) |
| 481 | png_handle_pCAL(png_ptr, info_ptr, length); |
| 482 | #endif |
| 483 | #if defined(PNG_READ_sCAL_SUPPORTED) |
| 484 | else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) |
| 485 | png_handle_sCAL(png_ptr, info_ptr, length); |
| 486 | #endif |
| 487 | #if defined(PNG_READ_pHYs_SUPPORTED) |
| 488 | else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) |
| 489 | png_handle_pHYs(png_ptr, info_ptr, length); |
| 490 | #endif |
| 491 | #if defined(PNG_READ_sBIT_SUPPORTED) |
| 492 | else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) |
| 493 | png_handle_sBIT(png_ptr, info_ptr, length); |
| 494 | #endif |
| 495 | #if defined(PNG_READ_sRGB_SUPPORTED) |
| 496 | else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) |
| 497 | png_handle_sRGB(png_ptr, info_ptr, length); |
| 498 | #endif |
| 499 | #if defined(PNG_READ_iCCP_SUPPORTED) |
| 500 | else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) |
| 501 | png_handle_iCCP(png_ptr, info_ptr, length); |
| 502 | #endif |
| 503 | #if defined(PNG_READ_sPLT_SUPPORTED) |
| 504 | else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) |
| 505 | png_handle_sPLT(png_ptr, info_ptr, length); |
| 506 | #endif |
| 507 | #if defined(PNG_READ_tEXt_SUPPORTED) |
| 508 | else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) |
| 509 | png_handle_tEXt(png_ptr, info_ptr, length); |
| 510 | #endif |
| 511 | #if defined(PNG_READ_tIME_SUPPORTED) |
| 512 | else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) |
| 513 | png_handle_tIME(png_ptr, info_ptr, length); |
| 514 | #endif |
| 515 | #if defined(PNG_READ_tRNS_SUPPORTED) |
| 516 | else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) |
| 517 | png_handle_tRNS(png_ptr, info_ptr, length); |
| 518 | #endif |
| 519 | #if defined(PNG_READ_zTXt_SUPPORTED) |
| 520 | else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) |
| 521 | png_handle_zTXt(png_ptr, info_ptr, length); |
| 522 | #endif |
| 523 | #if defined(PNG_READ_iTXt_SUPPORTED) |
| 524 | else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) |
| 525 | png_handle_iTXt(png_ptr, info_ptr, length); |
| 526 | #endif |
| 527 | else |
| 528 | png_handle_unknown(png_ptr, info_ptr, length); |
| 529 | } |
| 530 | } |
| 531 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 532 | |
| 533 | /* optional call to update the users info_ptr structure */ |
| 534 | void PNGAPI |
| 535 | png_read_update_info(png_structp png_ptr, png_infop info_ptr) |
| 536 | { |
| 537 | png_debug(1, "in png_read_update_info\n"); |
| 538 | if(png_ptr == NULL) return; |
| 539 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
| 540 | png_read_start_row(png_ptr); |
| 541 | else |
| 542 | png_warning(png_ptr, |
| 543 | "Ignoring extra png_read_update_info() call; row buffer not reallocated"); |
| 544 | png_read_transform_info(png_ptr, info_ptr); |
| 545 | } |
| 546 | |
| 547 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 548 | /* Initialize palette, background, etc, after transformations |
| 549 | * are set, but before any reading takes place. This allows |
| 550 | * the user to obtain a gamma-corrected palette, for example. |
| 551 | * If the user doesn't call this, we will do it ourselves. |
| 552 | */ |
| 553 | void PNGAPI |
| 554 | png_start_read_image(png_structp png_ptr) |
| 555 | { |
| 556 | png_debug(1, "in png_start_read_image\n"); |
| 557 | if(png_ptr == NULL) return; |
| 558 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
| 559 | png_read_start_row(png_ptr); |
| 560 | } |
| 561 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 562 | |
| 563 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 564 | void PNGAPI |
| 565 | png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) |
| 566 | { |
| 567 | #ifdef PNG_USE_LOCAL_ARRAYS |
| 568 | PNG_CONST PNG_IDAT; |
| 569 | PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, |
| 570 | 0xff}; |
| 571 | PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; |
| 572 | #endif |
| 573 | int ret; |
| 574 | if(png_ptr == NULL) return; |
| 575 | png_debug2(1, "in png_read_row (row %lu, pass %d)\n", |
| 576 | png_ptr->row_number, png_ptr->pass); |
| 577 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
| 578 | png_read_start_row(png_ptr); |
| 579 | if (png_ptr->row_number == 0 && png_ptr->pass == 0) |
| 580 | { |
| 581 | /* check for transforms that have been set but were defined out */ |
| 582 | #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) |
| 583 | if (png_ptr->transformations & PNG_INVERT_MONO) |
| 584 | png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined."); |
| 585 | #endif |
| 586 | #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) |
| 587 | if (png_ptr->transformations & PNG_FILLER) |
| 588 | png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined."); |
| 589 | #endif |
| 590 | #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED) |
| 591 | if (png_ptr->transformations & PNG_PACKSWAP) |
| 592 | png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined."); |
| 593 | #endif |
| 594 | #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) |
| 595 | if (png_ptr->transformations & PNG_PACK) |
| 596 | png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined."); |
| 597 | #endif |
| 598 | #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) |
| 599 | if (png_ptr->transformations & PNG_SHIFT) |
| 600 | png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined."); |
| 601 | #endif |
| 602 | #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) |
| 603 | if (png_ptr->transformations & PNG_BGR) |
| 604 | png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined."); |
| 605 | #endif |
| 606 | #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) |
| 607 | if (png_ptr->transformations & PNG_SWAP_BYTES) |
| 608 | png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined."); |
| 609 | #endif |
| 610 | } |
| 611 | |
| 612 | #if defined(PNG_READ_INTERLACING_SUPPORTED) |
| 613 | /* if interlaced and we do not need a new row, combine row and return */ |
| 614 | if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) |
| 615 | { |
| 616 | switch (png_ptr->pass) |
| 617 | { |
| 618 | case 0: |
| 619 | if (png_ptr->row_number & 0x07) |
| 620 | { |
| 621 | if (dsp_row != NULL) |
| 622 | png_combine_row(png_ptr, dsp_row, |
| 623 | png_pass_dsp_mask[png_ptr->pass]); |
| 624 | png_read_finish_row(png_ptr); |
| 625 | return; |
| 626 | } |
| 627 | break; |
| 628 | case 1: |
| 629 | if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) |
| 630 | { |
| 631 | if (dsp_row != NULL) |
| 632 | png_combine_row(png_ptr, dsp_row, |
| 633 | png_pass_dsp_mask[png_ptr->pass]); |
| 634 | png_read_finish_row(png_ptr); |
| 635 | return; |
| 636 | } |
| 637 | break; |
| 638 | case 2: |
| 639 | if ((png_ptr->row_number & 0x07) != 4) |
| 640 | { |
| 641 | if (dsp_row != NULL && (png_ptr->row_number & 4)) |
| 642 | png_combine_row(png_ptr, dsp_row, |
| 643 | png_pass_dsp_mask[png_ptr->pass]); |
| 644 | png_read_finish_row(png_ptr); |
| 645 | return; |
| 646 | } |
| 647 | break; |
| 648 | case 3: |
| 649 | if ((png_ptr->row_number & 3) || png_ptr->width < 3) |
| 650 | { |
| 651 | if (dsp_row != NULL) |
| 652 | png_combine_row(png_ptr, dsp_row, |
| 653 | png_pass_dsp_mask[png_ptr->pass]); |
| 654 | png_read_finish_row(png_ptr); |
| 655 | return; |
| 656 | } |
| 657 | break; |
| 658 | case 4: |
| 659 | if ((png_ptr->row_number & 3) != 2) |
| 660 | { |
| 661 | if (dsp_row != NULL && (png_ptr->row_number & 2)) |
| 662 | png_combine_row(png_ptr, dsp_row, |
| 663 | png_pass_dsp_mask[png_ptr->pass]); |
| 664 | png_read_finish_row(png_ptr); |
| 665 | return; |
| 666 | } |
| 667 | break; |
| 668 | case 5: |
| 669 | if ((png_ptr->row_number & 1) || png_ptr->width < 2) |
| 670 | { |
| 671 | if (dsp_row != NULL) |
| 672 | png_combine_row(png_ptr, dsp_row, |
| 673 | png_pass_dsp_mask[png_ptr->pass]); |
| 674 | png_read_finish_row(png_ptr); |
| 675 | return; |
| 676 | } |
| 677 | break; |
| 678 | case 6: |
| 679 | if (!(png_ptr->row_number & 1)) |
| 680 | { |
| 681 | png_read_finish_row(png_ptr); |
| 682 | return; |
| 683 | } |
| 684 | break; |
| 685 | } |
| 686 | } |
| 687 | #endif |
| 688 | |
| 689 | if (!(png_ptr->mode & PNG_HAVE_IDAT)) |
| 690 | png_error(png_ptr, "Invalid attempt to read row data"); |
| 691 | |
| 692 | png_ptr->zstream.next_out = png_ptr->row_buf; |
| 693 | png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; |
| 694 | do |
| 695 | { |
| 696 | if (!(png_ptr->zstream.avail_in)) |
| 697 | { |
| 698 | while (!png_ptr->idat_size) |
| 699 | { |
| 700 | png_byte chunk_length[4]; |
| 701 | |
| 702 | png_crc_finish(png_ptr, 0); |
| 703 | |
| 704 | png_read_data(png_ptr, chunk_length, 4); |
| 705 | png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length); |
| 706 | |
| 707 | png_reset_crc(png_ptr); |
| 708 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
| 709 | if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 710 | png_error(png_ptr, "Not enough image data"); |
| 711 | } |
| 712 | png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; |
| 713 | png_ptr->zstream.next_in = png_ptr->zbuf; |
| 714 | if (png_ptr->zbuf_size > png_ptr->idat_size) |
| 715 | png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; |
| 716 | png_crc_read(png_ptr, png_ptr->zbuf, |
| 717 | (png_size_t)png_ptr->zstream.avail_in); |
| 718 | png_ptr->idat_size -= png_ptr->zstream.avail_in; |
| 719 | } |
| 720 | ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); |
| 721 | if (ret == Z_STREAM_END) |
| 722 | { |
| 723 | if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || |
| 724 | png_ptr->idat_size) |
| 725 | png_error(png_ptr, "Extra compressed data"); |
| 726 | png_ptr->mode |= PNG_AFTER_IDAT; |
| 727 | png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
| 728 | break; |
| 729 | } |
| 730 | if (ret != Z_OK) |
| 731 | png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : |
| 732 | "Decompression error"); |
| 733 | |
| 734 | } while (png_ptr->zstream.avail_out); |
| 735 | |
| 736 | png_ptr->row_info.color_type = png_ptr->color_type; |
| 737 | png_ptr->row_info.width = png_ptr->iwidth; |
| 738 | png_ptr->row_info.channels = png_ptr->channels; |
| 739 | png_ptr->row_info.bit_depth = png_ptr->bit_depth; |
| 740 | png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; |
| 741 | png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, |
| 742 | png_ptr->row_info.width); |
| 743 | |
| 744 | if(png_ptr->row_buf[0]) |
| 745 | png_read_filter_row(png_ptr, &(png_ptr->row_info), |
| 746 | png_ptr->row_buf + 1, png_ptr->prev_row + 1, |
| 747 | (int)(png_ptr->row_buf[0])); |
| 748 | |
| 749 | png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, |
| 750 | png_ptr->rowbytes + 1); |
| 751 | |
| 752 | #if defined(PNG_MNG_FEATURES_SUPPORTED) |
| 753 | if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && |
| 754 | (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) |
| 755 | { |
| 756 | /* Intrapixel differencing */ |
| 757 | png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 758 | } |
| 759 | #endif |
| 760 | |
| 761 | |
| 762 | if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) |
| 763 | png_do_read_transformations(png_ptr); |
| 764 | |
| 765 | #if defined(PNG_READ_INTERLACING_SUPPORTED) |
| 766 | /* blow up interlaced rows to full size */ |
| 767 | if (png_ptr->interlaced && |
| 768 | (png_ptr->transformations & PNG_INTERLACE)) |
| 769 | { |
| 770 | if (png_ptr->pass < 6) |
| 771 | /* old interface (pre-1.0.9): |
| 772 | png_do_read_interlace(&(png_ptr->row_info), |
| 773 | png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); |
| 774 | */ |
| 775 | png_do_read_interlace(png_ptr); |
| 776 | |
| 777 | if (dsp_row != NULL) |
| 778 | png_combine_row(png_ptr, dsp_row, |
| 779 | png_pass_dsp_mask[png_ptr->pass]); |
| 780 | if (row != NULL) |
| 781 | png_combine_row(png_ptr, row, |
| 782 | png_pass_mask[png_ptr->pass]); |
| 783 | } |
| 784 | else |
| 785 | #endif |
| 786 | { |
| 787 | if (row != NULL) |
| 788 | png_combine_row(png_ptr, row, 0xff); |
| 789 | if (dsp_row != NULL) |
| 790 | png_combine_row(png_ptr, dsp_row, 0xff); |
| 791 | } |
| 792 | png_read_finish_row(png_ptr); |
| 793 | |
| 794 | if (png_ptr->read_row_fn != NULL) |
| 795 | (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); |
| 796 | } |
| 797 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 798 | |
| 799 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 800 | /* Read one or more rows of image data. If the image is interlaced, |
| 801 | * and png_set_interlace_handling() has been called, the rows need to |
| 802 | * contain the contents of the rows from the previous pass. If the |
| 803 | * image has alpha or transparency, and png_handle_alpha()[*] has been |
| 804 | * called, the rows contents must be initialized to the contents of the |
| 805 | * screen. |
| 806 | * |
| 807 | * "row" holds the actual image, and pixels are placed in it |
| 808 | * as they arrive. If the image is displayed after each pass, it will |
| 809 | * appear to "sparkle" in. "display_row" can be used to display a |
| 810 | * "chunky" progressive image, with finer detail added as it becomes |
| 811 | * available. If you do not want this "chunky" display, you may pass |
| 812 | * NULL for display_row. If you do not want the sparkle display, and |
| 813 | * you have not called png_handle_alpha(), you may pass NULL for rows. |
| 814 | * If you have called png_handle_alpha(), and the image has either an |
| 815 | * alpha channel or a transparency chunk, you must provide a buffer for |
| 816 | * rows. In this case, you do not have to provide a display_row buffer |
| 817 | * also, but you may. If the image is not interlaced, or if you have |
| 818 | * not called png_set_interlace_handling(), the display_row buffer will |
| 819 | * be ignored, so pass NULL to it. |
| 820 | * |
| 821 | * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
| 822 | */ |
| 823 | |
| 824 | void PNGAPI |
| 825 | png_read_rows(png_structp png_ptr, png_bytepp row, |
| 826 | png_bytepp display_row, png_uint_32 num_rows) |
| 827 | { |
| 828 | png_uint_32 i; |
| 829 | png_bytepp rp; |
| 830 | png_bytepp dp; |
| 831 | |
| 832 | png_debug(1, "in png_read_rows\n"); |
| 833 | if(png_ptr == NULL) return; |
| 834 | rp = row; |
| 835 | dp = display_row; |
| 836 | if (rp != NULL && dp != NULL) |
| 837 | for (i = 0; i < num_rows; i++) |
| 838 | { |
| 839 | png_bytep rptr = *rp++; |
| 840 | png_bytep dptr = *dp++; |
| 841 | |
| 842 | png_read_row(png_ptr, rptr, dptr); |
| 843 | } |
| 844 | else if(rp != NULL) |
| 845 | for (i = 0; i < num_rows; i++) |
| 846 | { |
| 847 | png_bytep rptr = *rp; |
| 848 | png_read_row(png_ptr, rptr, png_bytep_NULL); |
| 849 | rp++; |
| 850 | } |
| 851 | else if(dp != NULL) |
| 852 | for (i = 0; i < num_rows; i++) |
| 853 | { |
| 854 | png_bytep dptr = *dp; |
| 855 | png_read_row(png_ptr, png_bytep_NULL, dptr); |
| 856 | dp++; |
| 857 | } |
| 858 | } |
| 859 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 860 | |
| 861 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 862 | /* Read the entire image. If the image has an alpha channel or a tRNS |
| 863 | * chunk, and you have called png_handle_alpha()[*], you will need to |
| 864 | * initialize the image to the current image that PNG will be overlaying. |
| 865 | * We set the num_rows again here, in case it was incorrectly set in |
| 866 | * png_read_start_row() by a call to png_read_update_info() or |
| 867 | * png_start_read_image() if png_set_interlace_handling() wasn't called |
| 868 | * prior to either of these functions like it should have been. You can |
| 869 | * only call this function once. If you desire to have an image for |
| 870 | * each pass of a interlaced image, use png_read_rows() instead. |
| 871 | * |
| 872 | * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
| 873 | */ |
| 874 | void PNGAPI |
| 875 | png_read_image(png_structp png_ptr, png_bytepp image) |
| 876 | { |
| 877 | png_uint_32 i,image_height; |
| 878 | int pass, j; |
| 879 | png_bytepp rp; |
| 880 | |
| 881 | png_debug(1, "in png_read_image\n"); |
| 882 | if(png_ptr == NULL) return; |
| 883 | |
| 884 | #ifdef PNG_READ_INTERLACING_SUPPORTED |
| 885 | pass = png_set_interlace_handling(png_ptr); |
| 886 | #else |
| 887 | if (png_ptr->interlaced) |
| 888 | png_error(png_ptr, |
| 889 | "Cannot read interlaced image -- interlace handler disabled."); |
| 890 | pass = 1; |
| 891 | #endif |
| 892 | |
| 893 | |
| 894 | image_height=png_ptr->height; |
| 895 | png_ptr->num_rows = image_height; /* Make sure this is set correctly */ |
| 896 | |
| 897 | for (j = 0; j < pass; j++) |
| 898 | { |
| 899 | rp = image; |
| 900 | for (i = 0; i < image_height; i++) |
| 901 | { |
| 902 | png_read_row(png_ptr, *rp, png_bytep_NULL); |
| 903 | rp++; |
| 904 | } |
| 905 | } |
| 906 | } |
| 907 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 908 | |
| 909 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 910 | /* Read the end of the PNG file. Will not read past the end of the |
| 911 | * file, will verify the end is accurate, and will read any comments |
| 912 | * or time information at the end of the file, if info is not NULL. |
| 913 | */ |
| 914 | void PNGAPI |
| 915 | png_read_end(png_structp png_ptr, png_infop info_ptr) |
| 916 | { |
| 917 | png_byte chunk_length[4]; |
| 918 | png_uint_32 length; |
| 919 | |
| 920 | png_debug(1, "in png_read_end\n"); |
| 921 | if(png_ptr == NULL) return; |
| 922 | png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ |
| 923 | |
| 924 | do |
| 925 | { |
| 926 | #ifdef PNG_USE_LOCAL_ARRAYS |
| 927 | PNG_CONST PNG_IHDR; |
| 928 | PNG_CONST PNG_IDAT; |
| 929 | PNG_CONST PNG_IEND; |
| 930 | PNG_CONST PNG_PLTE; |
| 931 | #if defined(PNG_READ_bKGD_SUPPORTED) |
| 932 | PNG_CONST PNG_bKGD; |
| 933 | #endif |
| 934 | #if defined(PNG_READ_cHRM_SUPPORTED) |
| 935 | PNG_CONST PNG_cHRM; |
| 936 | #endif |
| 937 | #if defined(PNG_READ_gAMA_SUPPORTED) |
| 938 | PNG_CONST PNG_gAMA; |
| 939 | #endif |
| 940 | #if defined(PNG_READ_hIST_SUPPORTED) |
| 941 | PNG_CONST PNG_hIST; |
| 942 | #endif |
| 943 | #if defined(PNG_READ_iCCP_SUPPORTED) |
| 944 | PNG_CONST PNG_iCCP; |
| 945 | #endif |
| 946 | #if defined(PNG_READ_iTXt_SUPPORTED) |
| 947 | PNG_CONST PNG_iTXt; |
| 948 | #endif |
| 949 | #if defined(PNG_READ_oFFs_SUPPORTED) |
| 950 | PNG_CONST PNG_oFFs; |
| 951 | #endif |
| 952 | #if defined(PNG_READ_pCAL_SUPPORTED) |
| 953 | PNG_CONST PNG_pCAL; |
| 954 | #endif |
| 955 | #if defined(PNG_READ_pHYs_SUPPORTED) |
| 956 | PNG_CONST PNG_pHYs; |
| 957 | #endif |
| 958 | #if defined(PNG_READ_sBIT_SUPPORTED) |
| 959 | PNG_CONST PNG_sBIT; |
| 960 | #endif |
| 961 | #if defined(PNG_READ_sCAL_SUPPORTED) |
| 962 | PNG_CONST PNG_sCAL; |
| 963 | #endif |
| 964 | #if defined(PNG_READ_sPLT_SUPPORTED) |
| 965 | PNG_CONST PNG_sPLT; |
| 966 | #endif |
| 967 | #if defined(PNG_READ_sRGB_SUPPORTED) |
| 968 | PNG_CONST PNG_sRGB; |
| 969 | #endif |
| 970 | #if defined(PNG_READ_tEXt_SUPPORTED) |
| 971 | PNG_CONST PNG_tEXt; |
| 972 | #endif |
| 973 | #if defined(PNG_READ_tIME_SUPPORTED) |
| 974 | PNG_CONST PNG_tIME; |
| 975 | #endif |
| 976 | #if defined(PNG_READ_tRNS_SUPPORTED) |
| 977 | PNG_CONST PNG_tRNS; |
| 978 | #endif |
| 979 | #if defined(PNG_READ_zTXt_SUPPORTED) |
| 980 | PNG_CONST PNG_zTXt; |
| 981 | #endif |
| 982 | #endif /* PNG_USE_LOCAL_ARRAYS */ |
| 983 | |
| 984 | png_read_data(png_ptr, chunk_length, 4); |
| 985 | length = png_get_uint_31(png_ptr,chunk_length); |
| 986 | |
| 987 | png_reset_crc(png_ptr); |
| 988 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
| 989 | |
| 990 | png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name); |
| 991 | |
| 992 | if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) |
| 993 | png_handle_IHDR(png_ptr, info_ptr, length); |
| 994 | else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) |
| 995 | png_handle_IEND(png_ptr, info_ptr, length); |
| 996 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
| 997 | else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) |
| 998 | { |
| 999 | if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 1000 | { |
| 1001 | if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
| 1002 | png_error(png_ptr, "Too many IDAT's found"); |
| 1003 | } |
| 1004 | png_handle_unknown(png_ptr, info_ptr, length); |
| 1005 | if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
| 1006 | png_ptr->mode |= PNG_HAVE_PLTE; |
| 1007 | } |
| 1008 | #endif |
| 1009 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
| 1010 | { |
| 1011 | /* Zero length IDATs are legal after the last IDAT has been |
| 1012 | * read, but not after other chunks have been read. |
| 1013 | */ |
| 1014 | if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
| 1015 | png_error(png_ptr, "Too many IDAT's found"); |
| 1016 | png_crc_finish(png_ptr, length); |
| 1017 | } |
| 1018 | else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) |
| 1019 | png_handle_PLTE(png_ptr, info_ptr, length); |
| 1020 | #if defined(PNG_READ_bKGD_SUPPORTED) |
| 1021 | else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) |
| 1022 | png_handle_bKGD(png_ptr, info_ptr, length); |
| 1023 | #endif |
| 1024 | #if defined(PNG_READ_cHRM_SUPPORTED) |
| 1025 | else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) |
| 1026 | png_handle_cHRM(png_ptr, info_ptr, length); |
| 1027 | #endif |
| 1028 | #if defined(PNG_READ_gAMA_SUPPORTED) |
| 1029 | else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) |
| 1030 | png_handle_gAMA(png_ptr, info_ptr, length); |
| 1031 | #endif |
| 1032 | #if defined(PNG_READ_hIST_SUPPORTED) |
| 1033 | else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) |
| 1034 | png_handle_hIST(png_ptr, info_ptr, length); |
| 1035 | #endif |
| 1036 | #if defined(PNG_READ_oFFs_SUPPORTED) |
| 1037 | else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) |
| 1038 | png_handle_oFFs(png_ptr, info_ptr, length); |
| 1039 | #endif |
| 1040 | #if defined(PNG_READ_pCAL_SUPPORTED) |
| 1041 | else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) |
| 1042 | png_handle_pCAL(png_ptr, info_ptr, length); |
| 1043 | #endif |
| 1044 | #if defined(PNG_READ_sCAL_SUPPORTED) |
| 1045 | else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) |
| 1046 | png_handle_sCAL(png_ptr, info_ptr, length); |
| 1047 | #endif |
| 1048 | #if defined(PNG_READ_pHYs_SUPPORTED) |
| 1049 | else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) |
| 1050 | png_handle_pHYs(png_ptr, info_ptr, length); |
| 1051 | #endif |
| 1052 | #if defined(PNG_READ_sBIT_SUPPORTED) |
| 1053 | else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) |
| 1054 | png_handle_sBIT(png_ptr, info_ptr, length); |
| 1055 | #endif |
| 1056 | #if defined(PNG_READ_sRGB_SUPPORTED) |
| 1057 | else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) |
| 1058 | png_handle_sRGB(png_ptr, info_ptr, length); |
| 1059 | #endif |
| 1060 | #if defined(PNG_READ_iCCP_SUPPORTED) |
| 1061 | else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) |
| 1062 | png_handle_iCCP(png_ptr, info_ptr, length); |
| 1063 | #endif |
| 1064 | #if defined(PNG_READ_sPLT_SUPPORTED) |
| 1065 | else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) |
| 1066 | png_handle_sPLT(png_ptr, info_ptr, length); |
| 1067 | #endif |
| 1068 | #if defined(PNG_READ_tEXt_SUPPORTED) |
| 1069 | else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) |
| 1070 | png_handle_tEXt(png_ptr, info_ptr, length); |
| 1071 | #endif |
| 1072 | #if defined(PNG_READ_tIME_SUPPORTED) |
| 1073 | else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) |
| 1074 | png_handle_tIME(png_ptr, info_ptr, length); |
| 1075 | #endif |
| 1076 | #if defined(PNG_READ_tRNS_SUPPORTED) |
| 1077 | else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) |
| 1078 | png_handle_tRNS(png_ptr, info_ptr, length); |
| 1079 | #endif |
| 1080 | #if defined(PNG_READ_zTXt_SUPPORTED) |
| 1081 | else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) |
| 1082 | png_handle_zTXt(png_ptr, info_ptr, length); |
| 1083 | #endif |
| 1084 | #if defined(PNG_READ_iTXt_SUPPORTED) |
| 1085 | else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) |
| 1086 | png_handle_iTXt(png_ptr, info_ptr, length); |
| 1087 | #endif |
| 1088 | else |
| 1089 | png_handle_unknown(png_ptr, info_ptr, length); |
| 1090 | } while (!(png_ptr->mode & PNG_HAVE_IEND)); |
| 1091 | } |
| 1092 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 1093 | |
| 1094 | /* free all memory used by the read */ |
| 1095 | void PNGAPI |
| 1096 | png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, |
| 1097 | png_infopp end_info_ptr_ptr) |
| 1098 | { |
| 1099 | png_structp png_ptr = NULL; |
| 1100 | png_infop info_ptr = NULL, end_info_ptr = NULL; |
| 1101 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1102 | png_free_ptr free_fn; |
| 1103 | png_voidp mem_ptr; |
| 1104 | #endif |
| 1105 | |
| 1106 | png_debug(1, "in png_destroy_read_struct\n"); |
| 1107 | if (png_ptr_ptr != NULL) |
| 1108 | png_ptr = *png_ptr_ptr; |
| 1109 | |
| 1110 | if (info_ptr_ptr != NULL) |
| 1111 | info_ptr = *info_ptr_ptr; |
| 1112 | |
| 1113 | if (end_info_ptr_ptr != NULL) |
| 1114 | end_info_ptr = *end_info_ptr_ptr; |
| 1115 | |
| 1116 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1117 | free_fn = png_ptr->free_fn; |
| 1118 | mem_ptr = png_ptr->mem_ptr; |
| 1119 | #endif |
| 1120 | |
| 1121 | png_read_destroy(png_ptr, info_ptr, end_info_ptr); |
| 1122 | |
| 1123 | if (info_ptr != NULL) |
| 1124 | { |
| 1125 | #if defined(PNG_TEXT_SUPPORTED) |
| 1126 | png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); |
| 1127 | #endif |
| 1128 | |
| 1129 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1130 | png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, |
| 1131 | (png_voidp)mem_ptr); |
| 1132 | #else |
| 1133 | png_destroy_struct((png_voidp)info_ptr); |
| 1134 | #endif |
| 1135 | *info_ptr_ptr = NULL; |
| 1136 | } |
| 1137 | |
| 1138 | if (end_info_ptr != NULL) |
| 1139 | { |
| 1140 | #if defined(PNG_READ_TEXT_SUPPORTED) |
| 1141 | png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); |
| 1142 | #endif |
| 1143 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1144 | png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, |
| 1145 | (png_voidp)mem_ptr); |
| 1146 | #else |
| 1147 | png_destroy_struct((png_voidp)end_info_ptr); |
| 1148 | #endif |
| 1149 | *end_info_ptr_ptr = NULL; |
| 1150 | } |
| 1151 | |
| 1152 | if (png_ptr != NULL) |
| 1153 | { |
| 1154 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1155 | png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, |
| 1156 | (png_voidp)mem_ptr); |
| 1157 | #else |
| 1158 | png_destroy_struct((png_voidp)png_ptr); |
| 1159 | #endif |
| 1160 | *png_ptr_ptr = NULL; |
| 1161 | } |
| 1162 | } |
| 1163 | |
| 1164 | /* free all memory used by the read (old method) */ |
| 1165 | void /* PRIVATE */ |
| 1166 | png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr) |
| 1167 | { |
| 1168 | #ifdef PNG_SETJMP_SUPPORTED |
| 1169 | jmp_buf tmp_jmp; |
| 1170 | #endif |
| 1171 | png_error_ptr error_fn; |
| 1172 | png_error_ptr warning_fn; |
| 1173 | png_voidp error_ptr; |
| 1174 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1175 | png_free_ptr free_fn; |
| 1176 | #endif |
| 1177 | |
| 1178 | png_debug(1, "in png_read_destroy\n"); |
| 1179 | if (info_ptr != NULL) |
| 1180 | png_info_destroy(png_ptr, info_ptr); |
| 1181 | |
| 1182 | if (end_info_ptr != NULL) |
| 1183 | png_info_destroy(png_ptr, end_info_ptr); |
| 1184 | |
| 1185 | png_free(png_ptr, png_ptr->zbuf); |
| 1186 | png_free(png_ptr, png_ptr->big_row_buf); |
| 1187 | png_free(png_ptr, png_ptr->prev_row); |
| 1188 | #if defined(PNG_READ_DITHER_SUPPORTED) |
| 1189 | png_free(png_ptr, png_ptr->palette_lookup); |
| 1190 | png_free(png_ptr, png_ptr->dither_index); |
| 1191 | #endif |
| 1192 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
| 1193 | png_free(png_ptr, png_ptr->gamma_table); |
| 1194 | #endif |
| 1195 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 1196 | png_free(png_ptr, png_ptr->gamma_from_1); |
| 1197 | png_free(png_ptr, png_ptr->gamma_to_1); |
| 1198 | #endif |
| 1199 | #ifdef PNG_FREE_ME_SUPPORTED |
| 1200 | if (png_ptr->free_me & PNG_FREE_PLTE) |
| 1201 | png_zfree(png_ptr, png_ptr->palette); |
| 1202 | png_ptr->free_me &= ~PNG_FREE_PLTE; |
| 1203 | #else |
| 1204 | if (png_ptr->flags & PNG_FLAG_FREE_PLTE) |
| 1205 | png_zfree(png_ptr, png_ptr->palette); |
| 1206 | png_ptr->flags &= ~PNG_FLAG_FREE_PLTE; |
| 1207 | #endif |
| 1208 | #if defined(PNG_tRNS_SUPPORTED) || \ |
| 1209 | defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 1210 | #ifdef PNG_FREE_ME_SUPPORTED |
| 1211 | if (png_ptr->free_me & PNG_FREE_TRNS) |
| 1212 | png_free(png_ptr, png_ptr->trans); |
| 1213 | png_ptr->free_me &= ~PNG_FREE_TRNS; |
| 1214 | #else |
| 1215 | if (png_ptr->flags & PNG_FLAG_FREE_TRNS) |
| 1216 | png_free(png_ptr, png_ptr->trans); |
| 1217 | png_ptr->flags &= ~PNG_FLAG_FREE_TRNS; |
| 1218 | #endif |
| 1219 | #endif |
| 1220 | #if defined(PNG_READ_hIST_SUPPORTED) |
| 1221 | #ifdef PNG_FREE_ME_SUPPORTED |
| 1222 | if (png_ptr->free_me & PNG_FREE_HIST) |
| 1223 | png_free(png_ptr, png_ptr->hist); |
| 1224 | png_ptr->free_me &= ~PNG_FREE_HIST; |
| 1225 | #else |
| 1226 | if (png_ptr->flags & PNG_FLAG_FREE_HIST) |
| 1227 | png_free(png_ptr, png_ptr->hist); |
| 1228 | png_ptr->flags &= ~PNG_FLAG_FREE_HIST; |
| 1229 | #endif |
| 1230 | #endif |
| 1231 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
| 1232 | if (png_ptr->gamma_16_table != NULL) |
| 1233 | { |
| 1234 | int i; |
| 1235 | int istop = (1 << (8 - png_ptr->gamma_shift)); |
| 1236 | for (i = 0; i < istop; i++) |
| 1237 | { |
| 1238 | png_free(png_ptr, png_ptr->gamma_16_table[i]); |
| 1239 | } |
| 1240 | png_free(png_ptr, png_ptr->gamma_16_table); |
| 1241 | } |
| 1242 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 1243 | if (png_ptr->gamma_16_from_1 != NULL) |
| 1244 | { |
| 1245 | int i; |
| 1246 | int istop = (1 << (8 - png_ptr->gamma_shift)); |
| 1247 | for (i = 0; i < istop; i++) |
| 1248 | { |
| 1249 | png_free(png_ptr, png_ptr->gamma_16_from_1[i]); |
| 1250 | } |
| 1251 | png_free(png_ptr, png_ptr->gamma_16_from_1); |
| 1252 | } |
| 1253 | if (png_ptr->gamma_16_to_1 != NULL) |
| 1254 | { |
| 1255 | int i; |
| 1256 | int istop = (1 << (8 - png_ptr->gamma_shift)); |
| 1257 | for (i = 0; i < istop; i++) |
| 1258 | { |
| 1259 | png_free(png_ptr, png_ptr->gamma_16_to_1[i]); |
| 1260 | } |
| 1261 | png_free(png_ptr, png_ptr->gamma_16_to_1); |
| 1262 | } |
| 1263 | #endif |
| 1264 | #endif |
| 1265 | #if defined(PNG_TIME_RFC1123_SUPPORTED) |
| 1266 | png_free(png_ptr, png_ptr->time_buffer); |
| 1267 | #endif |
| 1268 | |
| 1269 | inflateEnd(&png_ptr->zstream); |
| 1270 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
| 1271 | png_free(png_ptr, png_ptr->save_buffer); |
| 1272 | #endif |
| 1273 | |
| 1274 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
| 1275 | #ifdef PNG_TEXT_SUPPORTED |
| 1276 | png_free(png_ptr, png_ptr->current_text); |
| 1277 | #endif /* PNG_TEXT_SUPPORTED */ |
| 1278 | #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
| 1279 | |
| 1280 | /* Save the important info out of the png_struct, in case it is |
| 1281 | * being used again. |
| 1282 | */ |
| 1283 | #ifdef PNG_SETJMP_SUPPORTED |
| 1284 | png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf)); |
| 1285 | #endif |
| 1286 | |
| 1287 | error_fn = png_ptr->error_fn; |
| 1288 | warning_fn = png_ptr->warning_fn; |
| 1289 | error_ptr = png_ptr->error_ptr; |
| 1290 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1291 | free_fn = png_ptr->free_fn; |
| 1292 | #endif |
| 1293 | |
| 1294 | png_memset(png_ptr, 0, png_sizeof (png_struct)); |
| 1295 | |
| 1296 | png_ptr->error_fn = error_fn; |
| 1297 | png_ptr->warning_fn = warning_fn; |
| 1298 | png_ptr->error_ptr = error_ptr; |
| 1299 | #ifdef PNG_USER_MEM_SUPPORTED |
| 1300 | png_ptr->free_fn = free_fn; |
| 1301 | #endif |
| 1302 | |
| 1303 | #ifdef PNG_SETJMP_SUPPORTED |
| 1304 | png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf)); |
| 1305 | #endif |
| 1306 | |
| 1307 | } |
| 1308 | |
| 1309 | void PNGAPI |
| 1310 | png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) |
| 1311 | { |
| 1312 | if(png_ptr == NULL) return; |
| 1313 | png_ptr->read_row_fn = read_row_fn; |
| 1314 | } |
| 1315 | |
| 1316 | |
| 1317 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
| 1318 | #if defined(PNG_INFO_IMAGE_SUPPORTED) |
| 1319 | void PNGAPI |
| 1320 | png_read_png(png_structp png_ptr, png_infop info_ptr, |
| 1321 | int transforms, |
| 1322 | voidp params) |
| 1323 | { |
| 1324 | int row; |
| 1325 | |
| 1326 | if(png_ptr == NULL) return; |
| 1327 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
| 1328 | /* invert the alpha channel from opacity to transparency |
| 1329 | */ |
| 1330 | if (transforms & PNG_TRANSFORM_INVERT_ALPHA) |
| 1331 | png_set_invert_alpha(png_ptr); |
| 1332 | #endif |
| 1333 | |
| 1334 | /* png_read_info() gives us all of the information from the |
| 1335 | * PNG file before the first IDAT (image data chunk). |
| 1336 | */ |
| 1337 | png_read_info(png_ptr, info_ptr); |
| 1338 | if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) |
| 1339 | png_error(png_ptr,"Image is too high to process with png_read_png()"); |
| 1340 | |
| 1341 | /* -------------- image transformations start here ------------------- */ |
| 1342 | |
| 1343 | #if defined(PNG_READ_16_TO_8_SUPPORTED) |
| 1344 | /* tell libpng to strip 16 bit/color files down to 8 bits per color |
| 1345 | */ |
| 1346 | if (transforms & PNG_TRANSFORM_STRIP_16) |
| 1347 | png_set_strip_16(png_ptr); |
| 1348 | #endif |
| 1349 | |
| 1350 | #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
| 1351 | /* Strip alpha bytes from the input data without combining with |
| 1352 | * the background (not recommended). |
| 1353 | */ |
| 1354 | if (transforms & PNG_TRANSFORM_STRIP_ALPHA) |
| 1355 | png_set_strip_alpha(png_ptr); |
| 1356 | #endif |
| 1357 | |
| 1358 | #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) |
| 1359 | /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single |
| 1360 | * byte into separate bytes (useful for paletted and grayscale images). |
| 1361 | */ |
| 1362 | if (transforms & PNG_TRANSFORM_PACKING) |
| 1363 | png_set_packing(png_ptr); |
| 1364 | #endif |
| 1365 | |
| 1366 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
| 1367 | /* Change the order of packed pixels to least significant bit first |
| 1368 | * (not useful if you are using png_set_packing). |
| 1369 | */ |
| 1370 | if (transforms & PNG_TRANSFORM_PACKSWAP) |
| 1371 | png_set_packswap(png_ptr); |
| 1372 | #endif |
| 1373 | |
| 1374 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
| 1375 | /* Expand paletted colors into true RGB triplets |
| 1376 | * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel |
| 1377 | * Expand paletted or RGB images with transparency to full alpha |
| 1378 | * channels so the data will be available as RGBA quartets. |
| 1379 | */ |
| 1380 | if (transforms & PNG_TRANSFORM_EXPAND) |
| 1381 | if ((png_ptr->bit_depth < 8) || |
| 1382 | (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || |
| 1383 | (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) |
| 1384 | png_set_expand(png_ptr); |
| 1385 | #endif |
| 1386 | |
| 1387 | /* We don't handle background color or gamma transformation or dithering. |
| 1388 | */ |
| 1389 | |
| 1390 | #if defined(PNG_READ_INVERT_SUPPORTED) |
| 1391 | /* invert monochrome files to have 0 as white and 1 as black |
| 1392 | */ |
| 1393 | if (transforms & PNG_TRANSFORM_INVERT_MONO) |
| 1394 | png_set_invert_mono(png_ptr); |
| 1395 | #endif |
| 1396 | |
| 1397 | #if defined(PNG_READ_SHIFT_SUPPORTED) |
| 1398 | /* If you want to shift the pixel values from the range [0,255] or |
| 1399 | * [0,65535] to the original [0,7] or [0,31], or whatever range the |
| 1400 | * colors were originally in: |
| 1401 | */ |
| 1402 | if ((transforms & PNG_TRANSFORM_SHIFT) |
| 1403 | && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) |
| 1404 | { |
| 1405 | png_color_8p sig_bit; |
| 1406 | |
| 1407 | png_get_sBIT(png_ptr, info_ptr, &sig_bit); |
| 1408 | png_set_shift(png_ptr, sig_bit); |
| 1409 | } |
| 1410 | #endif |
| 1411 | |
| 1412 | #if defined(PNG_READ_BGR_SUPPORTED) |
| 1413 | /* flip the RGB pixels to BGR (or RGBA to BGRA) |
| 1414 | */ |
| 1415 | if (transforms & PNG_TRANSFORM_BGR) |
| 1416 | png_set_bgr(png_ptr); |
| 1417 | #endif |
| 1418 | |
| 1419 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) |
| 1420 | /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) |
| 1421 | */ |
| 1422 | if (transforms & PNG_TRANSFORM_SWAP_ALPHA) |
| 1423 | png_set_swap_alpha(png_ptr); |
| 1424 | #endif |
| 1425 | |
| 1426 | #if defined(PNG_READ_SWAP_SUPPORTED) |
| 1427 | /* swap bytes of 16 bit files to least significant byte first |
| 1428 | */ |
| 1429 | if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) |
| 1430 | png_set_swap(png_ptr); |
| 1431 | #endif |
| 1432 | |
| 1433 | /* We don't handle adding filler bytes */ |
| 1434 | |
| 1435 | /* Optional call to gamma correct and add the background to the palette |
| 1436 | * and update info structure. REQUIRED if you are expecting libpng to |
| 1437 | * update the palette for you (i.e., you selected such a transform above). |
| 1438 | */ |
| 1439 | png_read_update_info(png_ptr, info_ptr); |
| 1440 | |
| 1441 | /* -------------- image transformations end here ------------------- */ |
| 1442 | |
| 1443 | #ifdef PNG_FREE_ME_SUPPORTED |
| 1444 | png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); |
| 1445 | #endif |
| 1446 | if(info_ptr->row_pointers == NULL) |
| 1447 | { |
| 1448 | info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, |
| 1449 | info_ptr->height * png_sizeof(png_bytep)); |
| 1450 | #ifdef PNG_FREE_ME_SUPPORTED |
| 1451 | info_ptr->free_me |= PNG_FREE_ROWS; |
| 1452 | #endif |
| 1453 | for (row = 0; row < (int)info_ptr->height; row++) |
| 1454 | { |
| 1455 | info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, |
| 1456 | png_get_rowbytes(png_ptr, info_ptr)); |
| 1457 | } |
| 1458 | } |
| 1459 | |
| 1460 | png_read_image(png_ptr, info_ptr->row_pointers); |
| 1461 | info_ptr->valid |= PNG_INFO_IDAT; |
| 1462 | |
| 1463 | /* read rest of file, and get additional chunks in info_ptr - REQUIRED */ |
| 1464 | png_read_end(png_ptr, info_ptr); |
| 1465 | |
| 1466 | transforms = transforms; /* quiet compiler warnings */ |
| 1467 | params = params; |
| 1468 | |
| 1469 | } |
| 1470 | #endif /* PNG_INFO_IMAGE_SUPPORTED */ |
| 1471 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
| 1472 | #endif /* PNG_READ_SUPPORTED */ |