pngget.c

   1
   2 /* pngget.c - retrieval of values from info struct
   3  *
   4  * Last changed in libpng 1.5.1 [February 3, 2011]
   5  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
   6  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
   7  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
   8  *
   9  * This code is released under the libpng license.
  10  * For conditions of distribution and use, see the disclaimer
  11  * and license in png.h
  12  *
  13  */
  14
  15 #include "pngpriv.h"
  16
  17 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
  18
  19 png_uint_32 PNGAPI
  20 png_get_valid(png_const_structp png_ptr, png_const_infop info_ptr,
  21     png_uint_32 flag)
  22 {
  23    if (png_ptr != NULL && info_ptr != NULL)
  24       return(info_ptr->valid & flag);
  25
  26    return(0);
  27 }
  28
  29 png_size_t PNGAPI
  30 png_get_rowbytes(png_const_structp png_ptr, png_const_infop info_ptr)
  31 {
  32    if (png_ptr != NULL && info_ptr != NULL)
  33       return(info_ptr->rowbytes);
  34
  35    return(0);
  36 }
  37
  38 #ifdef PNG_INFO_IMAGE_SUPPORTED
  39 png_bytepp PNGAPI
  40 png_get_rows(png_const_structp png_ptr, png_const_infop info_ptr)
  41 {
  42    if (png_ptr != NULL && info_ptr != NULL)
  43       return(info_ptr->row_pointers);
  44
  45    return(0);
  46 }
  47 #endif
  48
  49 #ifdef PNG_EASY_ACCESS_SUPPORTED
  50 /* Easy access to info, added in libpng-0.99 */
  51 png_uint_32 PNGAPI
  52 png_get_image_width(png_const_structp png_ptr, png_const_infop info_ptr)
  53 {
  54    if (png_ptr != NULL && info_ptr != NULL)
  55       return info_ptr->width;
  56
  57    return (0);
  58 }
  59
  60 png_uint_32 PNGAPI
  61 png_get_image_height(png_const_structp png_ptr, png_const_infop info_ptr)
  62 {
  63    if (png_ptr != NULL && info_ptr != NULL)
  64       return info_ptr->height;
  65
  66    return (0);
  67 }
  68
  69 png_byte PNGAPI
  70 png_get_bit_depth(png_const_structp png_ptr, png_const_infop info_ptr)
  71 {
  72    if (png_ptr != NULL && info_ptr != NULL)
  73       return info_ptr->bit_depth;
  74
  75    return (0);
  76 }
  77
  78 png_byte PNGAPI
  79 png_get_color_type(png_const_structp png_ptr, png_const_infop info_ptr)
  80 {
  81    if (png_ptr != NULL && info_ptr != NULL)
  82       return info_ptr->color_type;
  83
  84    return (0);
  85 }
  86
  87 png_byte PNGAPI
  88 png_get_filter_type(png_const_structp png_ptr, png_const_infop info_ptr)
  89 {
  90    if (png_ptr != NULL && info_ptr != NULL)
  91       return info_ptr->filter_type;
  92
  93    return (0);
  94 }
  95
  96 png_byte PNGAPI
  97 png_get_interlace_type(png_const_structp png_ptr, png_const_infop info_ptr)
  98 {
  99    if (png_ptr != NULL && info_ptr != NULL)
 100       return info_ptr->interlace_type;
 101
 102    return (0);
 103 }
 104
 105 png_byte PNGAPI
 106 png_get_compression_type(png_const_structp png_ptr, png_const_infop info_ptr)
 107 {
 108    if (png_ptr != NULL && info_ptr != NULL)
 109       return info_ptr->compression_type;
 110
 111    return (0);
 112 }
 113
 114 png_uint_32 PNGAPI
 115 png_get_x_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 116 {
 117 #ifdef PNG_pHYs_SUPPORTED
 118    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
 119       {
 120          png_debug1(1, "in %s retrieval function",
 121              "png_get_x_pixels_per_meter");
 122
 123          if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
 124             return (info_ptr->x_pixels_per_unit);
 125       }
 126 #endif
 127
 128    return (0);
 129 }
 130
 131 png_uint_32 PNGAPI
 132 png_get_y_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 133 {
 134 #ifdef PNG_pHYs_SUPPORTED
 135    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
 136    {
 137       png_debug1(1, "in %s retrieval function",
 138           "png_get_y_pixels_per_meter");
 139
 140       if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
 141          return (info_ptr->y_pixels_per_unit);
 142    }
 143 #endif
 144
 145    return (0);
 146 }
 147
 148 png_uint_32 PNGAPI
 149 png_get_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 150 {
 151 #ifdef PNG_pHYs_SUPPORTED
 152    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
 153    {
 154       png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");
 155
 156       if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER &&
 157           info_ptr->x_pixels_per_unit == info_ptr->y_pixels_per_unit)
 158          return (info_ptr->x_pixels_per_unit);
 159    }
 160 #endif
 161
 162    return (0);
 163 }
 164
 165 #ifdef PNG_FLOATING_POINT_SUPPORTED
 166 float PNGAPI
 167 png_get_pixel_aspect_ratio(png_const_structp png_ptr, png_const_infop info_ptr)
 168 {
 169 #ifdef PNG_READ_pHYs_SUPPORTED
 170    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
 171    {
 172       png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
 173
 174       if (info_ptr->x_pixels_per_unit != 0)
 175          return ((float)((float)info_ptr->y_pixels_per_unit
 176              /(float)info_ptr->x_pixels_per_unit));
 177    }
 178 #endif
 179
 180    return ((float)0.0);
 181 }
 182 #endif
 183
 184 #ifdef PNG_FIXED_POINT_SUPPORTED
 185 png_fixed_point PNGAPI
 186 png_get_pixel_aspect_ratio_fixed(png_const_structp png_ptr,
 187     png_const_infop info_ptr)
 188 {
 189 #ifdef PNG_READ_pHYs_SUPPORTED
 190    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
 191        && info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0
 192        && info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX
 193        && info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
 194    {
 195       png_fixed_point res;
 196
 197       png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio_fixed");
 198
 199       /* The following casts work because a PNG 4 byte integer only has a valid
 200        * range of 0..2^31-1; otherwise the cast might overflow.
 201        */
 202       if (png_muldiv(&res, (png_int_32)info_ptr->y_pixels_per_unit, PNG_FP_1,
 203           (png_int_32)info_ptr->x_pixels_per_unit))
 204          return res;
 205    }
 206 #endif
 207
 208    return 0;
 209 }
 210 #endif
 211
 212 png_int_32 PNGAPI
 213 png_get_x_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 214 {
 215 #ifdef PNG_oFFs_SUPPORTED
 216    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
 217    {
 218       png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
 219
 220       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
 221          return (info_ptr->x_offset);
 222    }
 223 #endif
 224
 225    return (0);
 226 }
 227
 228 png_int_32 PNGAPI
 229 png_get_y_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 230 {
 231 #ifdef PNG_oFFs_SUPPORTED
 232    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
 233    {
 234       png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
 235
 236       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
 237          return (info_ptr->y_offset);
 238    }
 239 #endif
 240
 241    return (0);
 242 }
 243
 244 png_int_32 PNGAPI
 245 png_get_x_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 246 {
 247 #ifdef PNG_oFFs_SUPPORTED
 248    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
 249    {
 250       png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
 251
 252       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
 253          return (info_ptr->x_offset);
 254    }
 255 #endif
 256
 257    return (0);
 258 }
 259
 260 png_int_32 PNGAPI
 261 png_get_y_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 262 {
 263 #ifdef PNG_oFFs_SUPPORTED
 264    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
 265    {
 266       png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
 267
 268       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
 269          return (info_ptr->y_offset);
 270    }
 271 #endif
 272
 273    return (0);
 274 }
 275
 276 #ifdef PNG_INCH_CONVERSIONS_SUPPORTED
 277 static png_uint_32
 278 ppi_from_ppm(png_uint_32 ppm)
 279 {
 280 #if 0
 281    /* The conversion is *(2.54/100), in binary (32 digits):
 282     * .00000110100000001001110101001001
 283     */
 284    png_uint_32 t1001, t1101;
 285    ppm >>= 1;                  /* .1 */
 286    t1001 = ppm + (ppm >> 3);   /* .1001 */
 287    t1101 = t1001 + (ppm >> 1); /* .1101 */
 288    ppm >>= 20;                 /* .000000000000000000001 */
 289    t1101 += t1101 >> 15;       /* .1101000000000001101 */
 290    t1001 >>= 11;               /* .000000000001001 */
 291    t1001 += t1001 >> 12;       /* .000000000001001000000001001 */
 292    ppm += t1001;               /* .000000000001001000001001001 */
 293    ppm += t1101;               /* .110100000001001110101001001 */
 294    return (ppm + 16) >> 5;/* .00000110100000001001110101001001 */
 295 #else
 296    /* The argument is a PNG unsigned integer, so it is not permitted
 297     * to be bigger than 2^31.
 298     */
 299    png_fixed_point result;
 300    if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, (png_int_32)ppm, 127,
 301        5000))
 302       return result;
 303
 304    /* Overflow. */
 305    return 0;
 306 #endif
 307 }
 308
 309 png_uint_32 PNGAPI
 310 png_get_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 311 {
 312    return ppi_from_ppm(png_get_pixels_per_meter(png_ptr, info_ptr));
 313 }
 314
 315 png_uint_32 PNGAPI
 316 png_get_x_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 317 {
 318    return ppi_from_ppm(png_get_x_pixels_per_meter(png_ptr, info_ptr));
 319 }
 320
 321 png_uint_32 PNGAPI
 322 png_get_y_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 323 {
 324    return ppi_from_ppm(png_get_y_pixels_per_meter(png_ptr, info_ptr));
 325 }
 326
 327 #ifdef PNG_FIXED_POINT_SUPPORTED
 328 static png_fixed_point
 329 png_fixed_inches_from_microns(png_structp png_ptr, png_int_32 microns)
 330 {
 331    /* Convert from metres * 1,000,000 to inches * 100,000, meters to
 332     * inches is simply *(100/2.54), so we want *(10/2.54) == 500/127.
 333     * Notice that this can overflow - a warning is output and 0 is
 334     * returned.
 335     */
 336    return png_muldiv_warn(png_ptr, microns, 500, 127);
 337 }
 338
 339 png_fixed_point PNGAPI
 340 png_get_x_offset_inches_fixed(png_structp png_ptr,
 341     png_const_infop info_ptr)
 342 {
 343    return png_fixed_inches_from_microns(png_ptr,
 344        png_get_x_offset_microns(png_ptr, info_ptr));
 345 }
 346 #endif
 347
 348 #ifdef PNG_FIXED_POINT_SUPPORTED
 349 png_fixed_point PNGAPI
 350 png_get_y_offset_inches_fixed(png_structp png_ptr,
 351     png_const_infop info_ptr)
 352 {
 353    return png_fixed_inches_from_microns(png_ptr,
 354        png_get_y_offset_microns(png_ptr, info_ptr));
 355 }
 356 #endif
 357
 358 #ifdef PNG_FLOATING_POINT_SUPPORTED
 359 float PNGAPI
 360 png_get_x_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 361 {
 362    /* To avoid the overflow do the conversion directly in floating
 363     * point.
 364     */
 365    return (float)(png_get_x_offset_microns(png_ptr, info_ptr) * .00003937);
 366 }
 367 #endif
 368
 369 #ifdef PNG_FLOATING_POINT_SUPPORTED
 370 float PNGAPI
 371 png_get_y_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 372 {
 373    /* To avoid the overflow do the conversion directly in floating
 374     * point.
 375     */
 376    return (float)(png_get_y_offset_microns(png_ptr, info_ptr) * .00003937);
 377 }
 378 #endif
 379
 380 #ifdef PNG_pHYs_SUPPORTED
 381 png_uint_32 PNGAPI
 382 png_get_pHYs_dpi(png_const_structp png_ptr, png_const_infop info_ptr,
 383     png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 384 {
 385    png_uint_32 retval = 0;
 386
 387    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
 388    {
 389       png_debug1(1, "in %s retrieval function", "pHYs");
 390
 391       if (res_x != NULL)
 392       {
 393          *res_x = info_ptr->x_pixels_per_unit;
 394          retval |= PNG_INFO_pHYs;
 395       }
 396
 397       if (res_y != NULL)
 398       {
 399          *res_y = info_ptr->y_pixels_per_unit;
 400          retval |= PNG_INFO_pHYs;
 401       }
 402
 403       if (unit_type != NULL)
 404       {
 405          *unit_type = (int)info_ptr->phys_unit_type;
 406          retval |= PNG_INFO_pHYs;
 407
 408          if (*unit_type == 1)
 409          {
 410             if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50);
 411             if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
 412          }
 413       }
 414    }
 415
 416    return (retval);
 417 }
 418 #endif /* PNG_pHYs_SUPPORTED */
 419 #endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
 420
 421 /* png_get_channels really belongs in here, too, but it's been around longer */
 422
 423 #endif  /* PNG_EASY_ACCESS_SUPPORTED */
 424
 425 png_byte PNGAPI
 426 png_get_channels(png_const_structp png_ptr, png_const_infop info_ptr)
 427 {
 428    if (png_ptr != NULL && info_ptr != NULL)
 429       return(info_ptr->channels);
 430
 431    return (0);
 432 }
 433
 434 png_const_bytep PNGAPI
 435 png_get_signature(png_const_structp png_ptr, png_infop info_ptr)
 436 {
 437    if (png_ptr != NULL && info_ptr != NULL)
 438       return(info_ptr->signature);
 439
 440    return (NULL);
 441 }
 442
 443 #ifdef PNG_bKGD_SUPPORTED
 444 png_uint_32 PNGAPI
 445 png_get_bKGD(png_const_structp png_ptr, png_infop info_ptr,
 446    png_color_16p *background)
 447 {
 448    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
 449        && background != NULL)
 450    {
 451       png_debug1(1, "in %s retrieval function", "bKGD");
 452
 453       *background = &(info_ptr->background);
 454       return (PNG_INFO_bKGD);
 455    }
 456
 457    return (0);
 458 }
 459 #endif
 460
 461 #ifdef PNG_cHRM_SUPPORTED
 462 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 463 png_uint_32 PNGAPI
 464 png_get_cHRM(png_const_structp png_ptr, png_const_infop info_ptr,
 465     double *white_x, double *white_y, double *red_x, double *red_y,
 466     double *green_x, double *green_y, double *blue_x, double *blue_y)
 467 {
 468    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
 469    {
 470       png_debug1(1, "in %s retrieval function", "cHRM");
 471
 472       if (white_x != NULL)
 473          *white_x = png_float(png_ptr, info_ptr->x_white, "cHRM white X");
 474       if (white_y != NULL)
 475          *white_y = png_float(png_ptr, info_ptr->y_white, "cHRM white Y");
 476       if (red_x != NULL)
 477          *red_x = png_float(png_ptr, info_ptr->x_red, "cHRM red X");
 478       if (red_y != NULL)
 479          *red_y = png_float(png_ptr, info_ptr->y_red, "cHRM red Y");
 480       if (green_x != NULL)
 481          *green_x = png_float(png_ptr, info_ptr->x_green, "cHRM green X");
 482       if (green_y != NULL)
 483          *green_y = png_float(png_ptr, info_ptr->y_green, "cHRM green Y");
 484       if (blue_x != NULL)
 485          *blue_x = png_float(png_ptr, info_ptr->x_blue, "cHRM blue X");
 486       if (blue_y != NULL)
 487          *blue_y = png_float(png_ptr, info_ptr->y_blue, "cHRM blue Y");
 488       return (PNG_INFO_cHRM);
 489    }
 490
 491    return (0);
 492 }
 493 #  endif
 494
 495 #  ifdef PNG_FIXED_POINT_SUPPORTED
 496 png_uint_32 PNGAPI
 497 png_get_cHRM_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
 498     png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
 499     png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
 500     png_fixed_point *blue_x, png_fixed_point *blue_y)
 501 {
 502    png_debug1(1, "in %s retrieval function", "cHRM");
 503
 504    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
 505    {
 506       if (white_x != NULL)
 507          *white_x = info_ptr->x_white;
 508       if (white_y != NULL)
 509          *white_y = info_ptr->y_white;
 510       if (red_x != NULL)
 511          *red_x = info_ptr->x_red;
 512       if (red_y != NULL)
 513          *red_y = info_ptr->y_red;
 514       if (green_x != NULL)
 515          *green_x = info_ptr->x_green;
 516       if (green_y != NULL)
 517          *green_y = info_ptr->y_green;
 518       if (blue_x != NULL)
 519          *blue_x = info_ptr->x_blue;
 520       if (blue_y != NULL)
 521          *blue_y = info_ptr->y_blue;
 522       return (PNG_INFO_cHRM);
 523    }
 524
 525    return (0);
 526 }
 527 #  endif
 528 #endif
 529
 530 #ifdef PNG_gAMA_SUPPORTED
 531 png_uint_32 PNGFAPI
 532 png_get_gAMA_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
 533     png_fixed_point *file_gamma)
 534 {
 535    png_debug1(1, "in %s retrieval function", "gAMA");
 536
 537    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
 538        && file_gamma != NULL)
 539    {
 540       *file_gamma = info_ptr->gamma;
 541       return (PNG_INFO_gAMA);
 542    }
 543
 544    return (0);
 545 }
 546 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 547 png_uint_32 PNGAPI
 548 png_get_gAMA(png_const_structp png_ptr, png_const_infop info_ptr,
 549     double *file_gamma)
 550 {
 551    png_fixed_point igamma;
 552    png_uint_32 ok = png_get_gAMA_fixed(png_ptr, info_ptr, &igamma);
 553
 554    if (ok)
 555       *file_gamma = png_float(png_ptr, igamma, "png_get_gAMA");
 556
 557    return ok;
 558 }
 559
 560 #  endif
 561 #endif
 562
 563 #ifdef PNG_sRGB_SUPPORTED
 564 png_uint_32 PNGAPI
 565 png_get_sRGB(png_const_structp png_ptr, png_const_infop info_ptr,
 566     int *file_srgb_intent)
 567 {
 568    png_debug1(1, "in %s retrieval function", "sRGB");
 569
 570    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
 571        && file_srgb_intent != NULL)
 572    {
 573       *file_srgb_intent = (int)info_ptr->srgb_intent;
 574       return (PNG_INFO_sRGB);
 575    }
 576
 577    return (0);
 578 }
 579 #endif
 580
 581 #ifdef PNG_iCCP_SUPPORTED
 582 png_uint_32 PNGAPI
 583 png_get_iCCP(png_const_structp png_ptr, png_const_infop info_ptr,
 584     png_charpp name, int *compression_type,
 585     png_bytepp profile, png_uint_32 *proflen)
 586 {
 587    png_debug1(1, "in %s retrieval function", "iCCP");
 588
 589    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
 590        && name != NULL && profile != NULL && proflen != NULL)
 591    {
 592       *name = info_ptr->iccp_name;
 593       *profile = info_ptr->iccp_profile;
 594       /* Compression_type is a dummy so the API won't have to change
 595        * if we introduce multiple compression types later.
 596        */
 597       *proflen = (int)info_ptr->iccp_proflen;
 598       *compression_type = (int)info_ptr->iccp_compression;
 599       return (PNG_INFO_iCCP);
 600    }
 601
 602    return (0);
 603 }
 604 #endif
 605
 606 #ifdef PNG_sPLT_SUPPORTED
 607 png_uint_32 PNGAPI
 608 png_get_sPLT(png_const_structp png_ptr, png_const_infop info_ptr,
 609     png_sPLT_tpp spalettes)
 610 {
 611    if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
 612    {
 613       *spalettes = info_ptr->splt_palettes;
 614       return ((png_uint_32)info_ptr->splt_palettes_num);
 615    }
 616
 617    return (0);
 618 }
 619 #endif
 620
 621 #ifdef PNG_hIST_SUPPORTED
 622 png_uint_32 PNGAPI
 623 png_get_hIST(png_const_structp png_ptr, png_const_infop info_ptr,
 624     png_uint_16p *hist)
 625 {
 626    png_debug1(1, "in %s retrieval function", "hIST");
 627
 628    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
 629        && hist != NULL)
 630    {
 631       *hist = info_ptr->hist;
 632       return (PNG_INFO_hIST);
 633    }
 634
 635    return (0);
 636 }
 637 #endif
 638
 639 png_uint_32 PNGAPI
 640 png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
 641     png_uint_32 *width, png_uint_32 *height, int *bit_depth,
 642     int *color_type, int *interlace_type, int *compression_type,
 643     int *filter_type)
 644
 645 {
 646    png_debug1(1, "in %s retrieval function", "IHDR");
 647
 648    if (png_ptr == NULL || info_ptr == NULL || width == NULL ||
 649        height == NULL || bit_depth == NULL || color_type == NULL)
 650       return (0);
 651
 652    *width = info_ptr->width;
 653    *height = info_ptr->height;
 654    *bit_depth = info_ptr->bit_depth;
 655    *color_type = info_ptr->color_type;
 656
 657    if (compression_type != NULL)
 658       *compression_type = info_ptr->compression_type;
 659
 660    if (filter_type != NULL)
 661       *filter_type = info_ptr->filter_type;
 662
 663    if (interlace_type != NULL)
 664       *interlace_type = info_ptr->interlace_type;
 665
 666    /* This is redundant if we can be sure that the info_ptr values were all
 667     * assigned in png_set_IHDR().  We do the check anyhow in case an
 668     * application has ignored our advice not to mess with the members
 669     * of info_ptr directly.
 670     */
 671    png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
 672        info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
 673        info_ptr->compression_type, info_ptr->filter_type);
 674
 675    return (1);
 676 }
 677
 678 #ifdef PNG_oFFs_SUPPORTED
 679 png_uint_32 PNGAPI
 680 png_get_oFFs(png_const_structp png_ptr, png_const_infop info_ptr,
 681     png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
 682 {
 683    png_debug1(1, "in %s retrieval function", "oFFs");
 684
 685    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
 686        && offset_x != NULL && offset_y != NULL && unit_type != NULL)
 687    {
 688       *offset_x = info_ptr->x_offset;
 689       *offset_y = info_ptr->y_offset;
 690       *unit_type = (int)info_ptr->offset_unit_type;
 691       return (PNG_INFO_oFFs);
 692    }
 693
 694    return (0);
 695 }
 696 #endif
 697
 698 #ifdef PNG_pCAL_SUPPORTED
 699 png_uint_32 PNGAPI
 700 png_get_pCAL(png_const_structp png_ptr, png_const_infop info_ptr,
 701     png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
 702     png_charp *units, png_charpp *params)
 703 {
 704    png_debug1(1, "in %s retrieval function", "pCAL");
 705
 706    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
 707        && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
 708        nparams != NULL && units != NULL && params != NULL)
 709    {
 710       *purpose = info_ptr->pcal_purpose;
 711       *X0 = info_ptr->pcal_X0;
 712       *X1 = info_ptr->pcal_X1;
 713       *type = (int)info_ptr->pcal_type;
 714       *nparams = (int)info_ptr->pcal_nparams;
 715       *units = info_ptr->pcal_units;
 716       *params = info_ptr->pcal_params;
 717       return (PNG_INFO_pCAL);
 718    }
 719
 720    return (0);
 721 }
 722 #endif
 723
 724 #ifdef PNG_sCAL_SUPPORTED
 725 #  ifdef PNG_FIXED_POINT_SUPPORTED
 726 #    ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
 727 png_uint_32 PNGAPI
 728 png_get_sCAL_fixed(png_structp png_ptr, png_const_infop info_ptr,
 729     int *unit, png_fixed_point *width, png_fixed_point *height)
 730 {
 731    if (png_ptr != NULL && info_ptr != NULL &&
 732        (info_ptr->valid & PNG_INFO_sCAL))
 733    {
 734       *unit = info_ptr->scal_unit;
 735       /*TODO: make this work without FP support */
 736       *width = png_fixed(png_ptr, atof(info_ptr->scal_s_width), "sCAL width");
 737       *height = png_fixed(png_ptr, atof(info_ptr->scal_s_height),
 738          "sCAL height");
 739       return (PNG_INFO_sCAL);
 740    }
 741
 742    return(0);
 743 }
 744 #    endif /* FLOATING_ARITHMETIC */
 745 #  endif /* FIXED_POINT */
 746 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 747 png_uint_32 PNGAPI
 748 png_get_sCAL(png_const_structp png_ptr, png_const_infop info_ptr,
 749     int *unit, double *width, double *height)
 750 {
 751    if (png_ptr != NULL && info_ptr != NULL &&
 752        (info_ptr->valid & PNG_INFO_sCAL))
 753    {
 754       *unit = info_ptr->scal_unit;
 755       *width = atof(info_ptr->scal_s_width);
 756       *height = atof(info_ptr->scal_s_height);
 757       return (PNG_INFO_sCAL);
 758    }
 759
 760    return(0);
 761 }
 762 #  endif /* FLOATING POINT */
 763 png_uint_32 PNGAPI
 764 png_get_sCAL_s(png_const_structp png_ptr, png_const_infop info_ptr,
 765     int *unit, png_charpp width, png_charpp height)
 766 {
 767    if (png_ptr != NULL && info_ptr != NULL &&
 768        (info_ptr->valid & PNG_INFO_sCAL))
 769    {
 770       *unit = info_ptr->scal_unit;
 771       *width = info_ptr->scal_s_width;
 772       *height = info_ptr->scal_s_height;
 773       return (PNG_INFO_sCAL);
 774    }
 775
 776    return(0);
 777 }
 778 #endif /* sCAL */
 779
 780 #ifdef PNG_pHYs_SUPPORTED
 781 png_uint_32 PNGAPI
 782 png_get_pHYs(png_const_structp png_ptr, png_const_infop info_ptr,
 783     png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 784 {
 785    png_uint_32 retval = 0;
 786
 787    png_debug1(1, "in %s retrieval function", "pHYs");
 788
 789    if (png_ptr != NULL && info_ptr != NULL &&
 790        (info_ptr->valid & PNG_INFO_pHYs))
 791    {
 792       if (res_x != NULL)
 793       {
 794          *res_x = info_ptr->x_pixels_per_unit;
 795          retval |= PNG_INFO_pHYs;
 796       }
 797
 798       if (res_y != NULL)
 799       {
 800          *res_y = info_ptr->y_pixels_per_unit;
 801          retval |= PNG_INFO_pHYs;
 802       }
 803
 804       if (unit_type != NULL)
 805       {
 806          *unit_type = (int)info_ptr->phys_unit_type;
 807          retval |= PNG_INFO_pHYs;
 808       }
 809    }
 810
 811    return (retval);
 812 }
 813 #endif /* pHYs */
 814
 815 png_uint_32 PNGAPI
 816 png_get_PLTE(png_const_structp png_ptr, png_const_infop info_ptr,
 817     png_colorp *palette, int *num_palette)
 818 {
 819    png_debug1(1, "in %s retrieval function", "PLTE");
 820
 821    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
 822        && palette != NULL)
 823    {
 824       *palette = info_ptr->palette;
 825       *num_palette = info_ptr->num_palette;
 826       png_debug1(3, "num_palette = %d", *num_palette);
 827       return (PNG_INFO_PLTE);
 828    }
 829
 830    return (0);
 831 }
 832
 833 #ifdef PNG_sBIT_SUPPORTED
 834 png_uint_32 PNGAPI
 835 png_get_sBIT(png_const_structp png_ptr, png_infop info_ptr,
 836     png_color_8p *sig_bit)
 837 {
 838    png_debug1(1, "in %s retrieval function", "sBIT");
 839
 840    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
 841        && sig_bit != NULL)
 842    {
 843       *sig_bit = &(info_ptr->sig_bit);
 844       return (PNG_INFO_sBIT);
 845    }
 846
 847    return (0);
 848 }
 849 #endif
 850
 851 #ifdef PNG_TEXT_SUPPORTED
 852 png_uint_32 PNGAPI
 853 png_get_text(png_const_structp png_ptr, png_const_infop info_ptr,
 854     png_textp *text_ptr, int *num_text)
 855 {
 856    if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
 857    {
 858       png_debug1(1, "in %s retrieval function",
 859           (png_ptr->chunk_name[0] == '\0' ? "text" :
 860           (png_const_charp)png_ptr->chunk_name));
 861
 862       if (text_ptr != NULL)
 863          *text_ptr = info_ptr->text;
 864
 865       if (num_text != NULL)
 866          *num_text = info_ptr->num_text;
 867
 868       return ((png_uint_32)info_ptr->num_text);
 869    }
 870
 871    if (num_text != NULL)
 872       *num_text = 0;
 873
 874    return(0);
 875 }
 876 #endif
 877
 878 #ifdef PNG_tIME_SUPPORTED
 879 png_uint_32 PNGAPI
 880 png_get_tIME(png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
 881 {
 882    png_debug1(1, "in %s retrieval function", "tIME");
 883
 884    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
 885        && mod_time != NULL)
 886    {
 887       *mod_time = &(info_ptr->mod_time);
 888       return (PNG_INFO_tIME);
 889    }
 890
 891    return (0);
 892 }
 893 #endif
 894
 895 #ifdef PNG_tRNS_SUPPORTED
 896 png_uint_32 PNGAPI
 897 png_get_tRNS(png_const_structp png_ptr, png_infop info_ptr,
 898     png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 899 {
 900    png_uint_32 retval = 0;
 901    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
 902    {
 903       png_debug1(1, "in %s retrieval function", "tRNS");
 904
 905       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
 906       {
 907          if (trans_alpha != NULL)
 908          {
 909             *trans_alpha = info_ptr->trans_alpha;
 910             retval |= PNG_INFO_tRNS;
 911          }
 912
 913          if (trans_color != NULL)
 914             *trans_color = &(info_ptr->trans_color);
 915       }
 916
 917       else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
 918       {
 919          if (trans_color != NULL)
 920          {
 921             *trans_color = &(info_ptr->trans_color);
 922             retval |= PNG_INFO_tRNS;
 923          }
 924
 925          if (trans_alpha != NULL)
 926             *trans_alpha = NULL;
 927       }
 928
 929       if (num_trans != NULL)
 930       {
 931          *num_trans = info_ptr->num_trans;
 932          retval |= PNG_INFO_tRNS;
 933       }
 934    }
 935
 936    return (retval);
 937 }
 938 #endif
 939
 940 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
 941 int PNGAPI
 942 png_get_unknown_chunks(png_const_structp png_ptr, png_const_infop info_ptr,
 943     png_unknown_chunkpp unknowns)
 944 {
 945    if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
 946    {
 947       *unknowns = info_ptr->unknown_chunks;
 948       return info_ptr->unknown_chunks_num;
 949    }
 950
 951    return (0);
 952 }
 953 #endif
 954
 955 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
 956 png_byte PNGAPI
 957 png_get_rgb_to_gray_status (png_const_structp png_ptr)
 958 {
 959    return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
 960 }
 961 #endif
 962
 963 #ifdef PNG_USER_CHUNKS_SUPPORTED
 964 png_voidp PNGAPI
 965 png_get_user_chunk_ptr(png_const_structp png_ptr)
 966 {
 967    return (png_ptr ? png_ptr->user_chunk_ptr : NULL);
 968 }
 969 #endif
 970
 971 png_size_t PNGAPI
 972 png_get_compression_buffer_size(png_const_structp png_ptr)
 973 {
 974    return (png_ptr ? png_ptr->zbuf_size : 0L);
 975 }
 976
 977
 978 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
 979 /* These functions were added to libpng 1.2.6 and were enabled
 980  * by default in libpng-1.4.0 */
 981 png_uint_32 PNGAPI
 982 png_get_user_width_max (png_const_structp png_ptr)
 983 {
 984    return (png_ptr ? png_ptr->user_width_max : 0);
 985 }
 986
 987 png_uint_32 PNGAPI
 988 png_get_user_height_max (png_const_structp png_ptr)
 989 {
 990    return (png_ptr ? png_ptr->user_height_max : 0);
 991 }
 992
 993 /* This function was added to libpng 1.4.0 */
 994 png_uint_32 PNGAPI
 995 png_get_chunk_cache_max (png_const_structp png_ptr)
 996 {
 997    return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
 998 }
 999
1000 /* This function was added to libpng 1.4.1 */
1001 png_alloc_size_t PNGAPI
1002 png_get_chunk_malloc_max (png_const_structp png_ptr)
1003 {
1004    return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
1005 }
1006 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
1007
1008 /* These functions were added to libpng 1.4.0 */
1009 #ifdef PNG_IO_STATE_SUPPORTED
1010 png_uint_32 PNGAPI
1011 png_get_io_state (png_structp png_ptr)
1012 {
1013    return png_ptr->io_state;
1014 }
1015
1016 png_uint_32 PNGAPI
1017 png_get_io_chunk_type (png_const_structp png_ptr)
1018 {
1019    return ((png_ptr->chunk_name[0] << 24) +
1020            (png_ptr->chunk_name[1] << 16) +
1021            (png_ptr->chunk_name[2] <<  8) +
1022            (png_ptr->chunk_name[3]));
1023 }
1024
1025 png_const_bytep PNGAPI
1026 png_get_io_chunk_name (png_structp png_ptr)
1027 {
1028    return png_ptr->chunk_name;
1029 }
1030 #endif /* ?PNG_IO_STATE_SUPPORTED */
1031
1032 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */