granicus.if.org Git - imagemagick/blob - coders/xcf.c

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %                            X   X   CCCC  FFFFF                              %
   7 %                             X X   C      F                                  %
   8 %                              X    C      FFF                                %
   9 %                             X X   C      F                                  %
  10 %                            X   X   CCCC  F                                  %
  11 %                                                                             %
  12 %                                                                             %
  13 %                        Read GIMP XCF Image Format                           %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                              Leonard Rosenthol                              %
  17 %                               November 2001                                 %
  18 %                                                                             %
  19 %                                                                             %
  20 %  Copyright 1999-2012 ImageMagick Studio LLC, a non-profit organization      %
  21 %  dedicated to making software imaging solutions freely available.           %
  22 %                                                                             %
  23 %  You may not use this file except in compliance with the License.  You may  %
  24 %  obtain a copy of the License at                                            %
  25 %                                                                             %
  26 %    http://www.imagemagick.org/script/license.php                            %
  27 %                                                                             %
  28 %  Unless required by applicable law or agreed to in writing, software        %
  29 %  distributed under the License is distributed on an "AS IS" BASIS,          %
  30 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
  31 %  See the License for the specific language governing permissions and        %
  32 %  limitations under the License.                                             %
  33 %                                                                             %
  34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  35 %
  36 %
  37 */
  38 \f
  39 /*
  40   Include declarations.
  41 */
  42 #include "MagickCore/studio.h"
  43 #include "MagickCore/blob.h"
  44 #include "MagickCore/blob-private.h"
  45 #include "MagickCore/cache.h"
  46 #include "MagickCore/color.h"
  47 #include "MagickCore/composite.h"
  48 #include "MagickCore/exception.h"
  49 #include "MagickCore/exception-private.h"
  50 #include "MagickCore/image.h"
  51 #include "MagickCore/image-private.h"
  52 #include "MagickCore/list.h"
  53 #include "MagickCore/magick.h"
  54 #include "MagickCore/memory_.h"
  55 #include "MagickCore/pixel.h"
  56 #include "MagickCore/pixel-accessor.h"
  57 #include "MagickCore/quantize.h"
  58 #include "MagickCore/quantum-private.h"
  59 #include "MagickCore/static.h"
  60 #include "MagickCore/string_.h"
  61 #include "MagickCore/module.h"
  62 \f
  63 /*
  64   Typedef declarations.
  65 */
  66 typedef enum
  67 {
  68   GIMP_RGB,
  69   GIMP_GRAY,
  70   GIMP_INDEXED
  71 } GimpImageBaseType;
  72
  73 typedef enum
  74 {
  75   PROP_END                   =  0,
  76   PROP_COLORMAP              =  1,
  77   PROP_ACTIVE_LAYER          =  2,
  78   PROP_ACTIVE_CHANNEL        =  3,
  79   PROP_SELECTION             =  4,
  80   PROP_FLOATING_SELECTION    =  5,
  81   PROP_OPACITY               =  6,
  82   PROP_MODE                  =  7,
  83   PROP_VISIBLE               =  8,
  84   PROP_LINKED                =  9,
  85   PROP_PRESERVE_TRANSPARENCY = 10,
  86   PROP_APPLY_MASK            = 11,
  87   PROP_EDIT_MASK             = 12,
  88   PROP_SHOW_MASK             = 13,
  89   PROP_SHOW_MASKED           = 14,
  90   PROP_OFFSETS               = 15,
  91   PROP_COLOR                 = 16,
  92   PROP_COMPRESSION           = 17,
  93   PROP_GUIDES                = 18,
  94   PROP_RESOLUTION            = 19,
  95   PROP_TATTOO                = 20,
  96   PROP_PARASITES             = 21,
  97   PROP_UNIT                  = 22,
  98   PROP_PATHS                 = 23,
  99   PROP_USER_UNIT             = 24
 100 } PropType;
 101
 102 typedef enum
 103 {
 104   COMPRESS_NONE              =  0,
 105   COMPRESS_RLE               =  1,
 106   COMPRESS_ZLIB              =  2,  /* unused */
 107   COMPRESS_FRACTAL           =  3   /* unused */
 108 } XcfCompressionType;
 109
 110 typedef struct
 111 {
 112   size_t
 113     width,
 114     height,
 115     image_type,
 116     bytes_per_pixel;
 117
 118   int
 119     compression;
 120
 121   size_t
 122     file_size;
 123
 124   ExceptionInfo
 125     *exception;
 126 } XCFDocInfo;
 127
 128 typedef struct
 129 {
 130   char
 131     name[1024];
 132
 133   unsigned int
 134     active;
 135
 136   size_t
 137     width,
 138     height,
 139     type,
 140     alpha,
 141     visible,
 142     linked,
 143     preserve_trans,
 144     apply_mask,
 145     show_mask,
 146     edit_mask,
 147     floating_offset;
 148
 149   ssize_t
 150     offset_x,
 151     offset_y;
 152
 153   size_t
 154     mode,
 155     tattoo;
 156
 157   Image
 158     *image;
 159 } XCFLayerInfo;
 160
 161 #define TILE_WIDTH   64
 162 #define TILE_HEIGHT  64
 163
 164 typedef struct
 165 {
 166   unsigned char
 167     red,
 168     green,
 169     blue,
 170     alpha;
 171 } XCFPixelInfo;
 172 \f
 173 /*
 174 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 175 %                                                                             %
 176 %                                                                             %
 177 %                                                                             %
 178 %   I s X C F                                                                 %
 179 %                                                                             %
 180 %                                                                             %
 181 %                                                                             %
 182 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 183 %
 184 %  IsXCF() returns MagickTrue if the image format type, identified by the
 185 %  magick string, is XCF (GIMP native format).
 186 %
 187 %  The format of the IsXCF method is:
 188 %
 189 %      MagickBooleanType IsXCF(const unsigned char *magick,const size_t length)
 190 %
 191 %  A description of each parameter follows:
 192 %
 193 %    o magick: compare image format pattern against these bytes.
 194 %
 195 %    o length: Specifies the length of the magick string.
 196 %
 197 %
 198 */
 199 static MagickBooleanType IsXCF(const unsigned char *magick,const size_t length)
 200 {
 201   if (length < 8)
 202     return(MagickFalse);
 203   if (LocaleNCompare((char *) magick,"gimp xcf",8) == 0)
 204     return(MagickTrue);
 205   return(MagickFalse);
 206 }
 207 \f
 208 typedef enum
 209 {
 210   GIMP_NORMAL_MODE,
 211   GIMP_DISSOLVE_MODE,
 212   GIMP_BEHIND_MODE,
 213   GIMP_MULTIPLY_MODE,
 214   GIMP_SCREEN_MODE,
 215   GIMP_OVERLAY_MODE,
 216   GIMP_DIFFERENCE_MODE,
 217   GIMP_ADDITION_MODE,
 218   GIMP_SUBTRACT_MODE,
 219   GIMP_DARKEN_ONLY_MODE,
 220   GIMP_LIGHTEN_ONLY_MODE,
 221   GIMP_HUE_MODE,
 222   GIMP_SATURATION_MODE,
 223   GIMP_COLOR_MODE,
 224   GIMP_VALUE_MODE,
 225   GIMP_DIVIDE_MODE,
 226   GIMP_DODGE_MODE,
 227   GIMP_BURN_MODE,
 228   GIMP_HARDLIGHT_MODE
 229 } GimpLayerModeEffects;
 230
 231 /*
 232   Simple utility routine to convert between PSD blending modes and
 233   ImageMagick compositing operators
 234 */
 235 static CompositeOperator GIMPBlendModeToCompositeOperator(
 236   size_t blendMode)
 237 {
 238   switch ( blendMode )
 239   {
 240     case GIMP_NORMAL_MODE:    return( OverCompositeOp );
 241     case GIMP_DISSOLVE_MODE:  return( DissolveCompositeOp );
 242     case GIMP_MULTIPLY_MODE:  return( MultiplyCompositeOp );
 243     case GIMP_SCREEN_MODE:    return( ScreenCompositeOp );
 244     case GIMP_OVERLAY_MODE:    return( OverlayCompositeOp );
 245     case GIMP_DIFFERENCE_MODE:  return( DifferenceCompositeOp );
 246     case GIMP_ADDITION_MODE:  return( ModulusAddCompositeOp );
 247     case GIMP_SUBTRACT_MODE:  return( ModulusSubtractCompositeOp );
 248     case GIMP_DARKEN_ONLY_MODE:  return( DarkenCompositeOp );
 249     case GIMP_LIGHTEN_ONLY_MODE:return( LightenCompositeOp );
 250     case GIMP_HUE_MODE:      return( HueCompositeOp );
 251     case GIMP_SATURATION_MODE:  return( SaturateCompositeOp );
 252     case GIMP_COLOR_MODE:    return( ColorizeCompositeOp );
 253     case GIMP_DODGE_MODE:    return( ColorDodgeCompositeOp );
 254     case GIMP_BURN_MODE:    return( ColorBurnCompositeOp );
 255     case GIMP_HARDLIGHT_MODE:  return( HardLightCompositeOp );
 256     case GIMP_DIVIDE_MODE:    return( DivideDstCompositeOp );
 257     /* these are the ones we don't support...yet */
 258     case GIMP_BEHIND_MODE:    return( OverCompositeOp );
 259     case GIMP_VALUE_MODE:    return( OverCompositeOp );
 260     default:
 261       return(OverCompositeOp);
 262   }
 263 }
 264 \f
 265 /*
 266 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 267 %                                                                             %
 268 %                                                                             %
 269 %                                                                             %
 270 +   R e a d B l o b S t r i n g W i t h L o n g S i z e                       %
 271 %                                                                             %
 272 %                                                                             %
 273 %                                                                             %
 274 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 275 %
 276 %  ReadBlobStringWithLongSize reads characters from a blob or file
 277 %  starting with a ssize_t length byte and then characters to that length
 278 %
 279 %  The format of the ReadBlobStringWithLongSize method is:
 280 %
 281 %      char *ReadBlobStringWithLongSize(Image *image,char *string)
 282 %
 283 %  A description of each parameter follows:
 284 %
 285 %    o image: the image.
 286 %
 287 %    o string: the address of a character buffer.
 288 %
 289 */
 290
 291 static inline size_t MagickMin(const size_t x,const size_t y)
 292 {
 293   if (x < y)
 294     return(x);
 295   return(y);
 296 }
 297
 298 static char *ReadBlobStringWithLongSize(Image *image,char *string,size_t max,
 299   ExceptionInfo *exception)
 300 {
 301   int
 302     c;
 303
 304   MagickOffsetType
 305     offset;
 306
 307   register ssize_t
 308     i;
 309
 310   size_t
 311     length;
 312
 313   assert(image != (Image *) NULL);
 314   assert(image->signature == MagickSignature);
 315   assert(max != 0);
 316   if (image->debug != MagickFalse)
 317     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 318   length=ReadBlobMSBLong(image);
 319   for (i=0; i < (ssize_t) MagickMin(length,max-1); i++)
 320   {
 321     c=ReadBlobByte(image);
 322     if (c == EOF)
 323       return((char *) NULL);
 324     string[i]=(char) c;
 325   }
 326   string[i]='\0';
 327   offset=SeekBlob(image,(MagickOffsetType) (length-i),SEEK_CUR);
 328   if (offset < 0)
 329     (void) ThrowMagickException(exception,GetMagickModule(),
 330       CorruptImageError,"ImproperImageHeader","`%s'",image->filename);
 331   return(string);
 332 }
 333
 334 static MagickBooleanType load_tile(Image *image,Image *tile_image,
 335   XCFDocInfo *inDocInfo,XCFLayerInfo *inLayerInfo,size_t data_length,
 336   ExceptionInfo *exception)
 337 {
 338   ssize_t
 339     y;
 340
 341   register ssize_t
 342     x;
 343
 344   register Quantum
 345     *q;
 346
 347   ssize_t
 348     count;
 349
 350   unsigned char
 351     *graydata;
 352
 353   XCFPixelInfo
 354     *xcfdata,
 355     *xcfodata;
 356
 357   xcfdata=(XCFPixelInfo *) AcquireQuantumMemory(data_length,sizeof(*xcfdata));
 358   if (xcfdata == (XCFPixelInfo *) NULL)
 359     ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
 360       image->filename);
 361   xcfodata=xcfdata;
 362   graydata=(unsigned char *) xcfdata;  /* used by gray and indexed */
 363   count=ReadBlob(image,data_length,(unsigned char *) xcfdata);
 364   if (count != (ssize_t) data_length)
 365     ThrowBinaryException(CorruptImageError,"NotEnoughPixelData",
 366       image->filename);
 367   for (y=0; y < (ssize_t) tile_image->rows; y++)
 368   {
 369     q=QueueAuthenticPixels(tile_image,0,y,tile_image->columns,1,exception);
 370     if (q == (Quantum *) NULL)
 371       break;
 372     if (inDocInfo->image_type == GIMP_GRAY)
 373       {
 374         for (x=0; x < (ssize_t) tile_image->columns; x++)
 375         {
 376           SetPixelRed(tile_image,ScaleCharToQuantum(*graydata),q);
 377           SetPixelGreen(tile_image,GetPixelRed(image,q),q);
 378           SetPixelBlue(tile_image,GetPixelRed(image,q),q);
 379           SetPixelAlpha(tile_image,ScaleCharToQuantum((unsigned char)
 380             inLayerInfo->alpha),q);
 381           graydata++;
 382           q+=GetPixelChannels(tile_image);
 383         }
 384       }
 385     else
 386       if (inDocInfo->image_type == GIMP_RGB)
 387         {
 388           for (x=0; x < (ssize_t) tile_image->columns; x++)
 389           {
 390             SetPixelRed(tile_image,ScaleCharToQuantum(xcfdata->red),q);
 391             SetPixelGreen(tile_image,ScaleCharToQuantum(xcfdata->green),q);
 392             SetPixelBlue(tile_image,ScaleCharToQuantum(xcfdata->blue),q);
 393             SetPixelAlpha(tile_image,xcfdata->alpha == 0U ? OpaqueAlpha :
 394               ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 395             xcfdata++;
 396             q+=GetPixelChannels(tile_image);
 397           }
 398         }
 399      if (SyncAuthenticPixels(tile_image,exception) == MagickFalse)
 400        break;
 401   }
 402   xcfodata=(XCFPixelInfo *) RelinquishMagickMemory(xcfodata);
 403   return MagickTrue;
 404 }
 405
 406 static MagickBooleanType load_tile_rle(Image *image,Image *tile_image,
 407   XCFDocInfo *inDocInfo,XCFLayerInfo *inLayerInfo,size_t data_length,
 408   ExceptionInfo *exception)
 409 {
 410   MagickOffsetType
 411     size;
 412
 413   register Quantum
 414     *q;
 415
 416   size_t
 417     length;
 418
 419   ssize_t
 420     bytes_per_pixel,
 421     count,
 422     i,
 423     j;
 424
 425   unsigned char
 426     data,
 427     pixel,
 428     *xcfdata,
 429     *xcfodata,
 430     *xcfdatalimit;
 431
 432   bytes_per_pixel=(ssize_t) inDocInfo->bytes_per_pixel;
 433   xcfdata=(unsigned char *) AcquireQuantumMemory(data_length,sizeof(*xcfdata));
 434   if (xcfdata == (unsigned char *) NULL)
 435     ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
 436       image->filename);
 437   xcfodata=xcfdata;
 438   count=ReadBlob(image, (size_t) data_length, xcfdata);
 439   xcfdatalimit = xcfodata+count-1;
 440   exception=(exception);
 441   for (i=0; i < (ssize_t) bytes_per_pixel; i++)
 442   {
 443     q=GetAuthenticPixels(tile_image,0,0,tile_image->columns,tile_image->rows,
 444       exception);
 445     size=(MagickOffsetType) tile_image->rows*tile_image->columns;
 446     while (size > 0)
 447     {
 448       if (xcfdata > xcfdatalimit)
 449         goto bogus_rle;
 450       pixel=(*xcfdata++);
 451       length=(size_t) pixel;
 452       if (length >= 128)
 453         {
 454           length=255-(length-1);
 455           if (length == 128)
 456             {
 457               if (xcfdata >= xcfdatalimit)
 458                 goto bogus_rle;
 459               length=(size_t) ((*xcfdata << 8) + xcfdata[1]);
 460               xcfdata+=2;
 461             }
 462             size-=length;
 463             if (size < 0)
 464               goto bogus_rle;
 465             if (&xcfdata[length-1] > xcfdatalimit)
 466               goto bogus_rle;
 467             while (length-- > 0)
 468             {
 469               data=(*xcfdata++);
 470               switch (i)
 471               {
 472                 case 0:
 473                 {
 474                   SetPixelRed(tile_image,ScaleCharToQuantum(data),q);
 475                   if (inDocInfo->image_type == GIMP_GRAY)
 476                     {
 477                       SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 478                       SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 479                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 480                         (unsigned char) inLayerInfo->alpha),q);
 481                     }
 482                   else
 483                     {
 484                       SetPixelGreen(tile_image,GetPixelRed(image,q),q);
 485                       SetPixelBlue(tile_image,GetPixelRed(image,q),q);
 486                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 487                         (unsigned char) inLayerInfo->alpha),q);
 488                     }
 489                   break;
 490                 }
 491                 case 1:
 492                 {
 493                   SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 494                   break;
 495                 }
 496                 case 2:
 497                 {
 498                   SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 499                   break;
 500                 }
 501                 case 3:
 502                 {
 503                   SetPixelAlpha(tile_image,data == 0 ? OpaqueAlpha :
 504                     ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 505                   break;
 506                 }
 507               }
 508               q+=GetPixelChannels(tile_image);
 509             }
 510           }
 511         else
 512           {
 513             length+=1;
 514             if (length == 128)
 515               {
 516                 if (xcfdata >= xcfdatalimit)
 517                   goto bogus_rle;
 518                 length=(size_t) ((*xcfdata << 8) + xcfdata[1]);
 519                 xcfdata+=2;
 520               }
 521             size-=length;
 522             if (size < 0)
 523               goto bogus_rle;
 524             if (xcfdata > xcfdatalimit)
 525               goto bogus_rle;
 526             pixel=(*xcfdata++);
 527             for (j= 0; j < (ssize_t) length; j++)
 528             {
 529               data=pixel;
 530               switch (i)
 531               {
 532                 case 0:
 533                 {
 534                   SetPixelRed(tile_image,ScaleCharToQuantum(data),q);
 535                   if (inDocInfo->image_type == GIMP_GRAY)
 536                     {
 537                       SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 538                       SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 539                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 540                         (unsigned char) inLayerInfo->alpha),q);
 541                     }
 542                   else
 543                     {
 544                       SetPixelGreen(tile_image,GetPixelRed(image,q),q);
 545                       SetPixelBlue(tile_image,GetPixelRed(image,q),q);
 546                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 547                         (unsigned char) inLayerInfo->alpha),q);
 548                     }
 549                   break;
 550                 }
 551                 case 1:
 552                 {
 553                   SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 554                   break;
 555                 }
 556                 case 2:
 557                 {
 558                   SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 559                   break;
 560                 }
 561                 case 3:
 562                 {
 563                   SetPixelAlpha(tile_image,data == 0 ? OpaqueAlpha :
 564                     ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 565                   break;
 566                 }
 567               }
 568               q+=GetPixelChannels(tile_image);
 569             }
 570           }
 571       }
 572       if (SyncAuthenticPixels(tile_image,exception) == MagickFalse)
 573         break;
 574     }
 575   xcfodata=(unsigned char *) RelinquishMagickMemory(xcfodata);
 576   return(MagickTrue);
 577
 578   bogus_rle:
 579     if (xcfodata != (unsigned char *) NULL)
 580       xcfodata=(unsigned char *) RelinquishMagickMemory(xcfodata);
 581   return(MagickFalse);
 582 }
 583
 584 static MagickBooleanType load_level(Image *image,XCFDocInfo *inDocInfo,
 585   XCFLayerInfo *inLayerInfo)
 586 {
 587   ExceptionInfo
 588     *exception;
 589
 590   int
 591     destLeft = 0,
 592     destTop = 0;
 593
 594   Image*
 595     tile_image;
 596
 597   MagickBooleanType
 598     status;
 599
 600   MagickOffsetType
 601     saved_pos,
 602     offset,
 603     offset2;
 604
 605   register ssize_t
 606     i;
 607
 608   size_t
 609     width,
 610     height,
 611     ntiles,
 612     ntile_rows,
 613     ntile_cols,
 614     tile_image_width,
 615     tile_image_height;
 616
 617   /* start reading the data */
 618   exception=inDocInfo->exception;
 619   width=ReadBlobMSBLong(image);
 620   height=ReadBlobMSBLong(image);
 621
 622   /* read in the first tile offset.
 623    *  if it is '0', then this tile level is empty
 624    *  and we can simply return.
 625    */
 626   offset=(MagickOffsetType) ReadBlobMSBLong(image);
 627   if (offset == 0)
 628     return(MagickTrue);
 629   /* Initialise the reference for the in-memory tile-compression
 630    */
 631   ntile_rows=(height+TILE_HEIGHT-1)/TILE_HEIGHT;
 632   ntile_cols=(width+TILE_WIDTH-1)/TILE_WIDTH;
 633   ntiles=ntile_rows*ntile_cols;
 634   for (i = 0; i < (ssize_t) ntiles; i++)
 635   {
 636     status=MagickFalse;
 637     if (offset == 0)
 638       ThrowBinaryException(CorruptImageError,"NotEnoughTiles",image->filename);
 639     /* save the current position as it is where the
 640      *  next tile offset is stored.
 641      */
 642     saved_pos=TellBlob(image);
 643     /* read in the offset of the next tile so we can calculate the amount
 644        of data needed for this tile*/
 645     offset2=(MagickOffsetType)ReadBlobMSBLong(image);
 646     /* if the offset is 0 then we need to read in the maximum possible
 647        allowing for negative compression */
 648     if (offset2 == 0)
 649       offset2=(MagickOffsetType) (offset + TILE_WIDTH * TILE_WIDTH * 4* 1.5);
 650     /* seek to the tile offset */
 651     offset=SeekBlob(image, offset, SEEK_SET);
 652
 653       /* allocate the image for the tile
 654         NOTE: the last tile in a row or column may not be a full tile!
 655       */
 656       tile_image_width=(size_t) (destLeft == (int) ntile_cols-1 ?
 657         (int) width % TILE_WIDTH : TILE_WIDTH);
 658       if (tile_image_width == 0) tile_image_width=TILE_WIDTH;
 659       tile_image_height = (size_t) (destTop == (int) ntile_rows-1 ?
 660         (int) height % TILE_HEIGHT : TILE_HEIGHT);
 661       if (tile_image_height == 0) tile_image_height=TILE_HEIGHT;
 662       tile_image=CloneImage(inLayerInfo->image,tile_image_width,
 663         tile_image_height,MagickTrue,exception);
 664
 665       /* read in the tile */
 666       switch (inDocInfo->compression)
 667       {
 668         case COMPRESS_NONE:
 669           if (load_tile(image,tile_image,inDocInfo,inLayerInfo,(size_t) (offset2-offset),exception) == 0)
 670             status=MagickTrue;
 671           break;
 672         case COMPRESS_RLE:
 673           if (load_tile_rle (image,tile_image,inDocInfo,inLayerInfo,
 674               (int) (offset2-offset),exception) == 0)
 675             status=MagickTrue;
 676           break;
 677         case COMPRESS_ZLIB:
 678           ThrowBinaryException(CoderError,"ZipCompressNotSupported",
 679             image->filename)
 680         case COMPRESS_FRACTAL:
 681           ThrowBinaryException(CoderError,"FractalCompressNotSupported",
 682             image->filename)
 683       }
 684
 685       /* composite the tile onto the layer's image, and then destroy it */
 686       (void) CompositeImage(inLayerInfo->image,CopyCompositeOp,tile_image,
 687         destLeft * TILE_WIDTH,destTop*TILE_HEIGHT,exception);
 688       tile_image=DestroyImage(tile_image);
 689
 690       /* adjust tile position */
 691       destLeft++;
 692       if (destLeft >= (int) ntile_cols)
 693         {
 694           destLeft = 0;
 695           destTop++;
 696         }
 697       if (status != MagickFalse)
 698         return(MagickFalse);
 699       /* restore the saved position so we'll be ready to
 700        *  read the next offset.
 701        */
 702       offset=SeekBlob(image, saved_pos, SEEK_SET);
 703       /* read in the offset of the next tile */
 704       offset=(MagickOffsetType) ReadBlobMSBLong(image);
 705     }
 706   if (offset != 0)
 707     ThrowBinaryException(CorruptImageError,"CorruptImage",image->filename)
 708   return(MagickTrue);
 709 }
 710
 711 static MagickBooleanType load_hierarchy(Image *image,XCFDocInfo *inDocInfo,
 712    XCFLayerInfo *inLayer)
 713 {
 714   MagickOffsetType
 715     saved_pos,
 716     offset,
 717     junk;
 718
 719   size_t
 720     width,
 721     height,
 722     bytes_per_pixel;
 723
 724   width=ReadBlobMSBLong(image);
 725   (void) width;
 726   height=ReadBlobMSBLong(image);
 727   (void) height;
 728   bytes_per_pixel=inDocInfo->bytes_per_pixel=ReadBlobMSBLong(image);
 729   (void) bytes_per_pixel;
 730
 731   /* load in the levels...we make sure that the number of levels
 732    *  calculated when the TileManager was created is the same
 733    *  as the number of levels found in the file.
 734    */
 735   offset=(MagickOffsetType) ReadBlobMSBLong(image);  /* top level */
 736
 737   /* discard offsets for layers below first, if any.
 738    */
 739   do
 740   {
 741     junk=(MagickOffsetType) ReadBlobMSBLong(image);
 742   }
 743   while (junk != 0);
 744
 745   /* save the current position as it is where the
 746    *  next level offset is stored.
 747    */
 748   saved_pos=TellBlob(image);
 749
 750   /* seek to the level offset */
 751   offset=SeekBlob(image, offset, SEEK_SET);
 752
 753   /* read in the level */
 754   if (load_level (image, inDocInfo, inLayer) == 0)
 755     return(MagickFalse);
 756   /* restore the saved position so we'll be ready to
 757    *  read the next offset.
 758    */
 759   offset=SeekBlob(image, saved_pos, SEEK_SET);
 760   return(MagickTrue);
 761 }
 762
 763 static MagickBooleanType ReadOneLayer(Image* image,XCFDocInfo* inDocInfo,
 764   XCFLayerInfo *outLayer, ExceptionInfo *exception )
 765 {
 766   MagickOffsetType
 767     offset;
 768
 769   unsigned int
 770     foundPropEnd = 0;
 771
 772   size_t
 773     hierarchy_offset,
 774     layer_mask_offset;
 775
 776   /* clear the block! */
 777   (void) ResetMagickMemory( outLayer, 0, sizeof( XCFLayerInfo ) );
 778   /* read in the layer width, height, type and name */
 779   outLayer->width = ReadBlobMSBLong(image);
 780   outLayer->height = ReadBlobMSBLong(image);
 781   outLayer->type = ReadBlobMSBLong(image);
 782   (void) ReadBlobStringWithLongSize(image, outLayer->name,
 783     sizeof(outLayer->name),exception);
 784   /* allocate the image for this layer */
 785   outLayer->image=CloneImage(image,outLayer->width, outLayer->height,MagickTrue,
 786      exception);
 787   if (outLayer->image == (Image *) NULL)
 788     return MagickFalse;
 789   /* read the layer properties! */
 790   foundPropEnd = 0;
 791   while ( (foundPropEnd == MagickFalse) && (EOFBlob(image) == MagickFalse) ) {
 792   PropType    prop_type = (PropType) ReadBlobMSBLong(image);
 793   size_t  prop_size = ReadBlobMSBLong(image);
 794     switch (prop_type)
 795     {
 796     case PROP_END:
 797       foundPropEnd = 1;
 798       break;
 799     case PROP_ACTIVE_LAYER:
 800       outLayer->active = 1;
 801       break;
 802     case PROP_FLOATING_SELECTION:
 803       outLayer->floating_offset = ReadBlobMSBLong(image);
 804       break;
 805     case PROP_OPACITY:
 806       outLayer->alpha = ReadBlobMSBLong(image);
 807       break;
 808     case PROP_VISIBLE:
 809       outLayer->visible = ReadBlobMSBLong(image);
 810       break;
 811     case PROP_LINKED:
 812       outLayer->linked = ReadBlobMSBLong(image);
 813       break;
 814     case PROP_PRESERVE_TRANSPARENCY:
 815       outLayer->preserve_trans = ReadBlobMSBLong(image);
 816       break;
 817     case PROP_APPLY_MASK:
 818       outLayer->apply_mask = ReadBlobMSBLong(image);
 819       break;
 820     case PROP_EDIT_MASK:
 821       outLayer->edit_mask = ReadBlobMSBLong(image);
 822       break;
 823     case PROP_SHOW_MASK:
 824       outLayer->show_mask = ReadBlobMSBLong(image);
 825       break;
 826     case PROP_OFFSETS:
 827       outLayer->offset_x = (int) ReadBlobMSBLong(image);
 828       outLayer->offset_y = (int) ReadBlobMSBLong(image);
 829       break;
 830     case PROP_MODE:
 831       outLayer->mode = ReadBlobMSBLong(image);
 832       break;
 833     case PROP_TATTOO:
 834       outLayer->preserve_trans = ReadBlobMSBLong(image);
 835       break;
 836      case PROP_PARASITES:
 837      {
 838        if (DiscardBlobBytes(image,prop_size) == MagickFalse)
 839          ThrowFileException(exception,CorruptImageError,
 840            "UnexpectedEndOfFile",image->filename);
 841
 842         /*
 843        ssize_t base = info->cp;
 844        GimpParasite *p;
 845        while (info->cp - base < prop_size)
 846        {
 847        p = xcf_load_parasite(info);
 848        gimp_drawable_parasite_attach(GIMP_DRAWABLE(layer), p);
 849        gimp_parasite_free(p);
 850        }
 851        if (info->cp - base != prop_size)
 852        g_message ("Error detected while loading a layer's parasites");
 853        */
 854      }
 855      break;
 856     default:
 857       /* g_message ("unexpected/unknown layer property: %d (skipping)",
 858          prop_type); */
 859
 860       {
 861       int buf[16];
 862       ssize_t amount;
 863
 864       /* read over it... */
 865       while ((prop_size > 0) && (EOFBlob(image) == MagickFalse))
 866         {
 867         amount = (ssize_t) MagickMin(16, prop_size);
 868         amount = ReadBlob(image, (size_t) amount, (unsigned char *) &buf);
 869         if (!amount)
 870           ThrowBinaryException(CorruptImageError,"CorruptImage",
 871             image->filename);
 872         prop_size -= (size_t) MagickMin(16, (size_t) amount);
 873         }
 874       }
 875       break;
 876     }
 877   }
 878
 879   if (foundPropEnd == MagickFalse)
 880     return(MagickFalse);
 881   /* clear the image based on the layer opacity */
 882   outLayer->image->background_color.alpha=
 883     ScaleCharToQuantum((unsigned char) (255-outLayer->alpha));
 884   (void) SetImageBackgroundColor(outLayer->image,exception);
 885
 886   /* set the compositing mode */
 887   outLayer->image->compose = GIMPBlendModeToCompositeOperator( outLayer->mode );
 888   if ( outLayer->visible == MagickFalse )
 889     {
 890       /* BOGUS: should really be separate member var! */
 891       outLayer->image->compose = NoCompositeOp;
 892     }
 893
 894   /* read the hierarchy and layer mask offsets */
 895   hierarchy_offset = ReadBlobMSBLong(image);
 896   layer_mask_offset = ReadBlobMSBLong(image);
 897
 898   /* read in the hierarchy */
 899   offset=SeekBlob(image, (MagickOffsetType) hierarchy_offset, SEEK_SET);
 900   if (offset < 0)
 901     (void) ThrowMagickException(exception,GetMagickModule(),
 902       CorruptImageError,"InvalidImageHeader","`%s'",image->filename);
 903   if (load_hierarchy (image, inDocInfo, outLayer) == 0)
 904     return(MagickFalse);
 905
 906   /* read in the layer mask */
 907   if (layer_mask_offset != 0)
 908     {
 909       offset=SeekBlob(image, (MagickOffsetType) layer_mask_offset, SEEK_SET);
 910
 911 #if 0  /* BOGUS: support layer masks! */
 912       layer_mask = xcf_load_layer_mask (info, gimage);
 913       if (layer_mask == 0)
 914   goto error;
 915
 916       /* set the offsets of the layer_mask */
 917       GIMP_DRAWABLE (layer_mask)->offset_x = GIMP_DRAWABLE (layer)->offset_x;
 918       GIMP_DRAWABLE (layer_mask)->offset_y = GIMP_DRAWABLE (layer)->offset_y;
 919
 920       gimp_layer_add_mask (layer, layer_mask, MagickFalse);
 921
 922       layer->mask->apply_mask = apply_mask;
 923       layer->mask->edit_mask  = edit_mask;
 924       layer->mask->show_mask  = show_mask;
 925 #endif
 926   }
 927
 928   /* attach the floating selection... */
 929 #if 0  /* BOGUS: we may need to read this, even if we don't support it! */
 930   if (add_floating_sel)
 931     {
 932       GimpLayer *floating_sel;
 933
 934       floating_sel = info->floating_sel;
 935       floating_sel_attach (floating_sel, GIMP_DRAWABLE (layer));
 936     }
 937 #endif
 938
 939   return MagickTrue;
 940 }
 941
 942 /*
 943 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 944 %                                                                             %
 945 %                                                                             %
 946 %                                                                             %
 947 %   R e a d X C F I m a g e                                                   %
 948 %                                                                             %
 949 %                                                                             %
 950 %                                                                             %
 951 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 952 %
 953 %  ReadXCFImage() reads a GIMP (GNU Image Manipulation Program) image
 954 %  file and returns it.  It allocates the memory necessary for the new Image
 955 %  structure and returns a pointer to the new image.
 956 %
 957 %  The format of the ReadXCFImage method is:
 958 %
 959 %      image=ReadXCFImage(image_info)
 960 %
 961 %  A description of each parameter follows:
 962 %
 963 %    o image_info: the image info.
 964 %
 965 %    o exception: return any errors or warnings in this structure.
 966 %
 967 %
 968 */
 969 static Image *ReadXCFImage(const ImageInfo *image_info,ExceptionInfo *exception)
 970 {
 971   char
 972     magick[14];
 973
 974   Image
 975     *image;
 976
 977   int
 978     foundPropEnd = 0;
 979
 980   MagickBooleanType
 981     status;
 982
 983   MagickOffsetType
 984     offset;
 985
 986   register ssize_t
 987     i;
 988
 989   size_t
 990     image_type,
 991     length;
 992
 993   ssize_t
 994     count;
 995
 996   XCFDocInfo
 997     doc_info;
 998
 999   /*
1000     Open image file.
1001   */
1002   assert(image_info != (const ImageInfo *) NULL);
1003   assert(image_info->signature == MagickSignature);
1004   if (image_info->debug != MagickFalse)
1005     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
1006       image_info->filename);
1007   assert(exception != (ExceptionInfo *) NULL);
1008   assert(exception->signature == MagickSignature);
1009   image=AcquireImage(image_info,exception);
1010   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
1011   if (status == MagickFalse)
1012     {
1013       image=DestroyImageList(image);
1014       return((Image *) NULL);
1015     }
1016   count=ReadBlob(image,14,(unsigned char *) magick);
1017   if ((count == 0) ||
1018       (LocaleNCompare((char *) magick,"gimp xcf",8) != 0))
1019     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1020   (void) ResetMagickMemory(&doc_info,0,sizeof(XCFDocInfo));
1021   doc_info.exception=exception;
1022   doc_info.width=ReadBlobMSBLong(image);
1023   doc_info.height=ReadBlobMSBLong(image);
1024   if ((doc_info.width > 262144) || (doc_info.height > 262144))
1025     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1026   doc_info.image_type=ReadBlobMSBLong(image);
1027   /*
1028     Initialize image attributes.
1029   */
1030   image->columns=doc_info.width;
1031   image->rows=doc_info.height;
1032   image_type=doc_info.image_type;
1033   doc_info.file_size=GetBlobSize(image);
1034   image->compression=NoCompression;
1035   image->depth=8;
1036   if (image_type == GIMP_RGB)
1037     image->colorspace=RGBColorspace;
1038   else
1039     if (image_type == GIMP_GRAY)
1040       image->colorspace=GRAYColorspace;
1041     else
1042       if (image_type == GIMP_INDEXED)
1043         ThrowReaderException(CoderError,"ColormapTypeNotSupported");
1044   (void) SetImageBackgroundColor(image,exception);
1045   image->matte=MagickTrue;
1046   /*
1047     Read properties.
1048   */
1049   while ((foundPropEnd == MagickFalse) && (EOFBlob(image) == MagickFalse))
1050   {
1051     PropType prop_type = (PropType) ReadBlobMSBLong(image);
1052     size_t prop_size = ReadBlobMSBLong(image);
1053
1054     switch (prop_type)
1055     {
1056       case PROP_END:
1057         foundPropEnd=1;
1058         break;
1059       case PROP_COLORMAP:
1060       {
1061         /* Cannot rely on prop_size here--the value is set incorrectly
1062            by some Gimp versions.
1063         */
1064         size_t num_colours = ReadBlobMSBLong(image);
1065         if (DiscardBlobBytes(image,3*num_colours) == MagickFalse)
1066           ThrowFileException(exception,CorruptImageError,
1067             "UnexpectedEndOfFile",image->filename);
1068     /*
1069       if (info->file_version == 0)
1070       {
1071         gint i;
1072
1073         g_message (_("XCF warning: version 0 of XCF file format\n"
1074            "did not save indexed colormaps correctly.\n"
1075            "Substituting grayscale map."));
1076         info->cp +=
1077           xcf_read_int32 (info->fp, (guint32*) &gimage->num_cols, 1);
1078         gimage->cmap = g_new (guchar, gimage->num_cols*3);
1079         xcf_seek_pos (info, info->cp + gimage->num_cols);
1080         for (i = 0; i<gimage->num_cols; i++)
1081           {
1082             gimage->cmap[i*3+0] = i;
1083             gimage->cmap[i*3+1] = i;
1084             gimage->cmap[i*3+2] = i;
1085           }
1086       }
1087       else
1088       {
1089         info->cp +=
1090           xcf_read_int32 (info->fp, (guint32*) &gimage->num_cols, 1);
1091         gimage->cmap = g_new (guchar, gimage->num_cols*3);
1092         info->cp +=
1093           xcf_read_int8 (info->fp,
1094                    (guint8*) gimage->cmap, gimage->num_cols*3);
1095       }
1096      */
1097         break;
1098       }
1099       case PROP_COMPRESSION:
1100       {
1101         doc_info.compression = ReadBlobByte(image);
1102         if ((doc_info.compression != COMPRESS_NONE) &&
1103             (doc_info.compression != COMPRESS_RLE) &&
1104             (doc_info.compression != COMPRESS_ZLIB) &&
1105             (doc_info.compression != COMPRESS_FRACTAL))
1106           ThrowReaderException(CorruptImageError,"UnrecognizedImageCompression");
1107       }
1108       break;
1109
1110       case PROP_GUIDES:
1111       {
1112          /* just skip it - we don't care about guides */
1113         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1114           ThrowFileException(exception,CorruptImageError,
1115             "UnexpectedEndOfFile",image->filename);
1116       }
1117       break;
1118
1119     case PROP_RESOLUTION:
1120       {
1121         /* float xres = (float) */ (void) ReadBlobMSBLong(image);
1122         /* float yres = (float) */ (void) ReadBlobMSBLong(image);
1123
1124         /*
1125         if (xres < GIMP_MIN_RESOLUTION || xres > GIMP_MAX_RESOLUTION ||
1126             yres < GIMP_MIN_RESOLUTION || yres > GIMP_MAX_RESOLUTION)
1127         {
1128         g_message ("Warning, resolution out of range in XCF file");
1129         xres = gimage->gimp->config->default_xresolution;
1130         yres = gimage->gimp->config->default_yresolution;
1131         }
1132         */
1133
1134
1135         /* BOGUS: we don't write these yet because we aren't
1136               reading them properly yet :(
1137               image->resolution.x = xres;
1138               image->resolution.y = yres;
1139         */
1140       }
1141       break;
1142
1143     case PROP_TATTOO:
1144       {
1145         /* we need to read it, even if we ignore it */
1146         /*size_t  tattoo_state = */ (void) ReadBlobMSBLong(image);
1147       }
1148       break;
1149
1150     case PROP_PARASITES:
1151       {
1152         /* BOGUS: we may need these for IPTC stuff */
1153         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1154           ThrowFileException(exception,CorruptImageError,
1155             "UnexpectedEndOfFile",image->filename);
1156         /*
1157       gssize_t         base = info->cp;
1158       GimpParasite *p;
1159
1160       while (info->cp - base < prop_size)
1161         {
1162           p = xcf_load_parasite (info);
1163           gimp_image_parasite_attach (gimage, p);
1164           gimp_parasite_free (p);
1165         }
1166       if (info->cp - base != prop_size)
1167         g_message ("Error detected while loading an image's parasites");
1168       */
1169           }
1170       break;
1171
1172     case PROP_UNIT:
1173       {
1174         /* BOGUS: ignore for now... */
1175       /*size_t unit =  */ (void) ReadBlobMSBLong(image);
1176       }
1177       break;
1178
1179     case PROP_PATHS:
1180       {
1181       /* BOGUS: just skip it for now */
1182         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1183           ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
1184             image->filename);
1185
1186         /*
1187       PathList *paths = xcf_load_bzpaths (gimage, info);
1188       gimp_image_set_paths (gimage, paths);
1189       */
1190       }
1191       break;
1192
1193     case PROP_USER_UNIT:
1194       {
1195         char  unit_string[1000];
1196         /*BOGUS: ignored for now */
1197         /*float  factor = (float) */ (void) ReadBlobMSBLong(image);
1198         /* size_t digits =  */ (void) ReadBlobMSBLong(image);
1199         for (i=0; i<5; i++)
1200          (void) ReadBlobStringWithLongSize(image, unit_string,
1201            sizeof(unit_string),exception);
1202       }
1203      break;
1204
1205       default:
1206       {
1207         int buf[16];
1208         ssize_t amount;
1209
1210       /* read over it... */
1211       while ((prop_size > 0) && (EOFBlob(image) == MagickFalse))
1212       {
1213         amount=(ssize_t) MagickMin(16, prop_size);
1214         amount=(ssize_t) ReadBlob(image,(size_t) amount,(unsigned char *) &buf);
1215         if (!amount)
1216           ThrowReaderException(CorruptImageError,"CorruptImage");
1217         prop_size -= (size_t) MagickMin(16,(size_t) amount);
1218       }
1219     }
1220     break;
1221   }
1222   }
1223   if (foundPropEnd == MagickFalse)
1224     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1225
1226   if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
1227     {
1228       ; /* do nothing, were just pinging! */
1229     }
1230   else
1231     {
1232       int
1233         current_layer = 0,
1234         foundAllLayers = MagickFalse,
1235         number_layers = 0;
1236
1237       MagickOffsetType
1238         oldPos=TellBlob(image);
1239
1240       XCFLayerInfo
1241         *layer_info;
1242
1243       /*
1244         the read pointer
1245       */
1246       do
1247       {
1248         ssize_t offset = (int) ReadBlobMSBLong(image);
1249         if (offset == 0)
1250           foundAllLayers=MagickTrue;
1251         else
1252           number_layers++;
1253         if (EOFBlob(image) != MagickFalse)
1254           {
1255             ThrowFileException(exception,CorruptImageError,
1256               "UnexpectedEndOfFile",image->filename);
1257             break;
1258           }
1259     } while (foundAllLayers == MagickFalse);
1260     offset=SeekBlob(image,oldPos,SEEK_SET); /* restore the position! */
1261     if (offset < 0)
1262       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1263     /* allocate our array of layer info blocks */
1264     length=(size_t) number_layers;
1265     layer_info=(XCFLayerInfo *) AcquireQuantumMemory(length,
1266       sizeof(*layer_info));
1267     if (layer_info == (XCFLayerInfo *) NULL)
1268       ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
1269     (void) ResetMagickMemory(layer_info,0,number_layers*sizeof(XCFLayerInfo));
1270     for ( ; ; )
1271     {
1272       MagickBooleanType
1273         layer_ok;
1274
1275       MagickOffsetType
1276         offset,
1277         saved_pos;
1278
1279       /* read in the offset of the next layer */
1280       offset=(MagickOffsetType) ReadBlobMSBLong(image);
1281       /* if the offset is 0 then we are at the end
1282       *  of the layer list.
1283       */
1284       if (offset == 0)
1285         break;
1286       /* save the current position as it is where the
1287       *  next layer offset is stored.
1288       */
1289       saved_pos=TellBlob(image);
1290       /* seek to the layer offset */
1291       offset=SeekBlob(image,offset,SEEK_SET);
1292       /* read in the layer */
1293       layer_ok=ReadOneLayer(image,&doc_info,&layer_info[current_layer],
1294         exception);
1295       if (layer_ok == MagickFalse)
1296         {
1297           int j;
1298
1299           for (j=0; j < current_layer; j++)
1300             layer_info[j].image=DestroyImage(layer_info[j].image);
1301         ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
1302       }
1303       /* restore the saved position so we'll be ready to
1304       *  read the next offset.
1305       */
1306       offset=SeekBlob(image, saved_pos, SEEK_SET);
1307       current_layer++;
1308     }
1309     if (number_layers == 1)
1310       {
1311         /*
1312           Composite the layer data onto the main image, dispose the layer.
1313         */
1314         (void) CompositeImage(image,OverCompositeOp,layer_info[0].image,
1315           layer_info[0].offset_x,layer_info[0].offset_y,exception);
1316         layer_info[0].image =DestroyImage( layer_info[0].image);
1317       }
1318     else
1319       {
1320 #if 0
1321         {
1322         /* NOTE: XCF layers are REVERSED from composite order! */
1323         signed int  j;
1324         for (j=number_layers-1; j>=0; j--) {
1325           /* BOGUS: need to consider layer blending modes!! */
1326
1327           if ( layer_info[j].visible ) { /* only visible ones, please! */
1328             CompositeImage(image, OverCompositeOp, layer_info[j].image,
1329                      layer_info[j].offset_x, layer_info[j].offset_y );
1330              layer_info[j].image =DestroyImage( layer_info[j].image );
1331
1332             /* Bob says that if we do this, we'll get REAL gray images! */
1333             if ( image_type == GIMP_GRAY ) {
1334               QuantizeInfo  qi;
1335               GetQuantizeInfo(&qi);
1336               qi.colorspace = GRAYColorspace;
1337               QuantizeImage( &qi, layer_info[j].image );
1338             }
1339           }
1340         }
1341       }
1342 #else
1343       {
1344         /* NOTE: XCF layers are REVERSED from composite order! */
1345         signed int  j;
1346
1347         /* first we copy the last layer on top of the main image */
1348         (void) CompositeImage(image,CopyCompositeOp,
1349           layer_info[number_layers-1].image,
1350           layer_info[number_layers-1].offset_x,
1351           layer_info[number_layers-1].offset_y,exception);
1352           layer_info[number_layers-1].image=DestroyImage(
1353             layer_info[number_layers-1].image);
1354
1355         /* now reverse the order of the layers as they are put
1356            into subimages
1357         */
1358         j=number_layers-2;
1359         image->next=layer_info[j].image;
1360         layer_info[j].image->previous=image;
1361         layer_info[j].image->page.x=layer_info[j].offset_x;
1362         layer_info[j].image->page.y=layer_info[j].offset_y;
1363         layer_info[j].image->page.width=layer_info[j].width;
1364         layer_info[j].image->page.height=layer_info[j].height;
1365         for (j=number_layers-3; j>=0; j--)
1366         {
1367           if (j > 0)
1368             layer_info[j].image->next=layer_info[j-1].image;
1369           if (j < (number_layers-1))
1370             layer_info[j].image->previous=layer_info[j+1].image;
1371           layer_info[j].image->page.x=layer_info[j].offset_x;
1372           layer_info[j].image->page.y=layer_info[j].offset_y;
1373           layer_info[j].image->page.width=layer_info[j].width;
1374           layer_info[j].image->page.height=layer_info[j].height;
1375         }
1376       }
1377 #endif
1378     }
1379
1380     layer_info=(XCFLayerInfo *) RelinquishMagickMemory(layer_info);
1381
1382 #if 0  /* BOGUS: do we need the channels?? */
1383     while (MagickTrue)
1384     {
1385       /* read in the offset of the next channel */
1386       info->cp += xcf_read_int32 (info->fp, &offset, 1);
1387
1388       /* if the offset is 0 then we are at the end
1389       *  of the channel list.
1390       */
1391       if (offset == 0)
1392         break;
1393
1394       /* save the current position as it is where the
1395       *  next channel offset is stored.
1396       */
1397       saved_pos = info->cp;
1398
1399       /* seek to the channel offset */
1400       xcf_seek_pos (info, offset);
1401
1402       /* read in the layer */
1403       channel = xcf_load_channel (info, gimage);
1404       if (channel == 0)
1405         goto error;
1406
1407       num_successful_elements++;
1408
1409       /* add the channel to the image if its not the selection */
1410       if (channel != gimage->selection_mask)
1411         gimp_image_add_channel (gimage, channel, -1);
1412
1413       /* restore the saved position so we'll be ready to
1414       *  read the next offset.
1415       */
1416       xcf_seek_pos (info, saved_pos);
1417     }
1418 #endif
1419   }
1420
1421   (void) CloseBlob(image);
1422   if (image_type == GIMP_GRAY)
1423     image->type=GrayscaleType;
1424   return(GetFirstImageInList(image));
1425 }
1426 \f
1427 /*
1428 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1429 %                                                                             %
1430 %                                                                             %
1431 %                                                                             %
1432 %   R e g i s t e r X C F I m a g e                                           %
1433 %                                                                             %
1434 %                                                                             %
1435 %                                                                             %
1436 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1437 %
1438 %  RegisterXCFImage() adds attributes for the XCF image format to
1439 %  the list of supported formats.  The attributes include the image format
1440 %  tag, a method to read and/or write the format, whether the format
1441 %  supports the saving of more than one frame to the same file or blob,
1442 %  whether the format supports native in-memory I/O, and a brief
1443 %  description of the format.
1444 %
1445 %  The format of the RegisterXCFImage method is:
1446 %
1447 %      size_t RegisterXCFImage(void)
1448 %
1449 */
1450 ModuleExport size_t RegisterXCFImage(void)
1451 {
1452   MagickInfo
1453     *entry;
1454
1455   entry=SetMagickInfo("XCF");
1456   entry->decoder=(DecodeImageHandler *) ReadXCFImage;
1457   entry->magick=(IsImageFormatHandler *) IsXCF;
1458   entry->description=ConstantString("GIMP image");
1459   entry->module=ConstantString("XCF");
1460   entry->seekable_stream=MagickTrue;
1461   (void) RegisterMagickInfo(entry);
1462   return(MagickImageCoderSignature);
1463 }
1464 \f
1465 /*
1466 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1467 %                                                                             %
1468 %                                                                             %
1469 %                                                                             %
1470 %   U n r e g i s t e r X C F I m a g e                                       %
1471 %                                                                             %
1472 %                                                                             %
1473 %                                                                             %
1474 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1475 %
1476 %  UnregisterXCFImage() removes format registrations made by the
1477 %  XCF module from the list of supported formats.
1478 %
1479 %  The format of the UnregisterXCFImage method is:
1480 %
1481 %      UnregisterXCFImage(void)
1482 %
1483 */
1484 ModuleExport void UnregisterXCFImage(void)
1485 {
1486   (void) UnregisterMagickInfo("XCF");
1487 }