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           SetPixelGray(tile_image,ScaleCharToQuantum(*graydata),q);
 377           SetPixelAlpha(tile_image,ScaleCharToQuantum((unsigned char)
 378             inLayerInfo->alpha),q);
 379           graydata++;
 380           q+=GetPixelChannels(tile_image);
 381         }
 382       }
 383     else
 384       if (inDocInfo->image_type == GIMP_RGB)
 385         {
 386           for (x=0; x < (ssize_t) tile_image->columns; x++)
 387           {
 388             SetPixelRed(tile_image,ScaleCharToQuantum(xcfdata->red),q);
 389             SetPixelGreen(tile_image,ScaleCharToQuantum(xcfdata->green),q);
 390             SetPixelBlue(tile_image,ScaleCharToQuantum(xcfdata->blue),q);
 391             SetPixelAlpha(tile_image,xcfdata->alpha == 0U ? OpaqueAlpha :
 392               ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 393             xcfdata++;
 394             q+=GetPixelChannels(tile_image);
 395           }
 396         }
 397      if (SyncAuthenticPixels(tile_image,exception) == MagickFalse)
 398        break;
 399   }
 400   xcfodata=(XCFPixelInfo *) RelinquishMagickMemory(xcfodata);
 401   return MagickTrue;
 402 }
 403
 404 static MagickBooleanType load_tile_rle(Image *image,Image *tile_image,
 405   XCFDocInfo *inDocInfo,XCFLayerInfo *inLayerInfo,size_t data_length,
 406   ExceptionInfo *exception)
 407 {
 408   MagickOffsetType
 409     size;
 410
 411   register Quantum
 412     *q;
 413
 414   size_t
 415     length;
 416
 417   ssize_t
 418     bytes_per_pixel,
 419     count,
 420     i,
 421     j;
 422
 423   unsigned char
 424     data,
 425     pixel,
 426     *xcfdata,
 427     *xcfodata,
 428     *xcfdatalimit;
 429
 430   bytes_per_pixel=(ssize_t) inDocInfo->bytes_per_pixel;
 431   xcfdata=(unsigned char *) AcquireQuantumMemory(data_length,sizeof(*xcfdata));
 432   if (xcfdata == (unsigned char *) NULL)
 433     ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
 434       image->filename);
 435   xcfodata=xcfdata;
 436   count=ReadBlob(image, (size_t) data_length, xcfdata);
 437   xcfdatalimit = xcfodata+count-1;
 438   exception=(exception);
 439   for (i=0; i < (ssize_t) bytes_per_pixel; i++)
 440   {
 441     q=GetAuthenticPixels(tile_image,0,0,tile_image->columns,tile_image->rows,
 442       exception);
 443     size=(MagickOffsetType) tile_image->rows*tile_image->columns;
 444     while (size > 0)
 445     {
 446       if (xcfdata > xcfdatalimit)
 447         goto bogus_rle;
 448       pixel=(*xcfdata++);
 449       length=(size_t) pixel;
 450       if (length >= 128)
 451         {
 452           length=255-(length-1);
 453           if (length == 128)
 454             {
 455               if (xcfdata >= xcfdatalimit)
 456                 goto bogus_rle;
 457               length=(size_t) ((*xcfdata << 8) + xcfdata[1]);
 458               xcfdata+=2;
 459             }
 460             size-=length;
 461             if (size < 0)
 462               goto bogus_rle;
 463             if (&xcfdata[length-1] > xcfdatalimit)
 464               goto bogus_rle;
 465             while (length-- > 0)
 466             {
 467               data=(*xcfdata++);
 468               switch (i)
 469               {
 470                 case 0:
 471                 {
 472                   if (inDocInfo->image_type != GIMP_GRAY)
 473                     {
 474                       SetPixelRed(tile_image,ScaleCharToQuantum(data),q);
 475                       SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 476                       SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 477                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 478                         (unsigned char) inLayerInfo->alpha),q);
 479                     }
 480                   else
 481                     {
 482                       SetPixelGray(tile_image,ScaleCharToQuantum(data),q);
 483                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 484                         (unsigned char) inLayerInfo->alpha),q);
 485                     }
 486                   break;
 487                 }
 488                 case 1:
 489                 {
 490                   SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 491                   break;
 492                 }
 493                 case 2:
 494                 {
 495                   SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 496                   break;
 497                 }
 498                 case 3:
 499                 {
 500                   SetPixelAlpha(tile_image,data == 0 ? OpaqueAlpha :
 501                     ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 502                   break;
 503                 }
 504               }
 505               q+=GetPixelChannels(tile_image);
 506             }
 507           }
 508         else
 509           {
 510             length+=1;
 511             if (length == 128)
 512               {
 513                 if (xcfdata >= xcfdatalimit)
 514                   goto bogus_rle;
 515                 length=(size_t) ((*xcfdata << 8) + xcfdata[1]);
 516                 xcfdata+=2;
 517               }
 518             size-=length;
 519             if (size < 0)
 520               goto bogus_rle;
 521             if (xcfdata > xcfdatalimit)
 522               goto bogus_rle;
 523             pixel=(*xcfdata++);
 524             for (j= 0; j < (ssize_t) length; j++)
 525             {
 526               data=pixel;
 527               switch (i)
 528               {
 529                 case 0:
 530                 {
 531                   if (inDocInfo->image_type != GIMP_GRAY)
 532                     {
 533                       SetPixelRed(tile_image,ScaleCharToQuantum(data),q);
 534                       SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 535                       SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 536                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 537                         (unsigned char) inLayerInfo->alpha),q);
 538                     }
 539                   else
 540                     {
 541                       SetPixelGray(tile_image,ScaleCharToQuantum(data),q);
 542                       SetPixelAlpha(tile_image,ScaleCharToQuantum(
 543                         (unsigned char) inLayerInfo->alpha),q);
 544                     }
 545                   break;
 546                 }
 547                 case 1:
 548                 {
 549                   SetPixelGreen(tile_image,ScaleCharToQuantum(data),q);
 550                   break;
 551                 }
 552                 case 2:
 553                 {
 554                   SetPixelBlue(tile_image,ScaleCharToQuantum(data),q);
 555                   break;
 556                 }
 557                 case 3:
 558                 {
 559                   SetPixelAlpha(tile_image,data == 0 ? OpaqueAlpha :
 560                     ScaleCharToQuantum((unsigned char) inLayerInfo->alpha),q);
 561                   break;
 562                 }
 563               }
 564               q+=GetPixelChannels(tile_image);
 565             }
 566           }
 567       }
 568       if (SyncAuthenticPixels(tile_image,exception) == MagickFalse)
 569         break;
 570     }
 571   xcfodata=(unsigned char *) RelinquishMagickMemory(xcfodata);
 572   return(MagickTrue);
 573
 574   bogus_rle:
 575     if (xcfodata != (unsigned char *) NULL)
 576       xcfodata=(unsigned char *) RelinquishMagickMemory(xcfodata);
 577   return(MagickFalse);
 578 }
 579
 580 static MagickBooleanType load_level(Image *image,XCFDocInfo *inDocInfo,
 581   XCFLayerInfo *inLayerInfo)
 582 {
 583   ExceptionInfo
 584     *exception;
 585
 586   int
 587     destLeft = 0,
 588     destTop = 0;
 589
 590   Image*
 591     tile_image;
 592
 593   MagickBooleanType
 594     status;
 595
 596   MagickOffsetType
 597     saved_pos,
 598     offset,
 599     offset2;
 600
 601   register ssize_t
 602     i;
 603
 604   size_t
 605     width,
 606     height,
 607     ntiles,
 608     ntile_rows,
 609     ntile_cols,
 610     tile_image_width,
 611     tile_image_height;
 612
 613   /* start reading the data */
 614   exception=inDocInfo->exception;
 615   width=ReadBlobMSBLong(image);
 616   height=ReadBlobMSBLong(image);
 617
 618   /* read in the first tile offset.
 619    *  if it is '0', then this tile level is empty
 620    *  and we can simply return.
 621    */
 622   offset=(MagickOffsetType) ReadBlobMSBLong(image);
 623   if (offset == 0)
 624     return(MagickTrue);
 625   /* Initialise the reference for the in-memory tile-compression
 626    */
 627   ntile_rows=(height+TILE_HEIGHT-1)/TILE_HEIGHT;
 628   ntile_cols=(width+TILE_WIDTH-1)/TILE_WIDTH;
 629   ntiles=ntile_rows*ntile_cols;
 630   for (i = 0; i < (ssize_t) ntiles; i++)
 631   {
 632     status=MagickFalse;
 633     if (offset == 0)
 634       ThrowBinaryException(CorruptImageError,"NotEnoughTiles",image->filename);
 635     /* save the current position as it is where the
 636      *  next tile offset is stored.
 637      */
 638     saved_pos=TellBlob(image);
 639     /* read in the offset of the next tile so we can calculate the amount
 640        of data needed for this tile*/
 641     offset2=(MagickOffsetType)ReadBlobMSBLong(image);
 642     /* if the offset is 0 then we need to read in the maximum possible
 643        allowing for negative compression */
 644     if (offset2 == 0)
 645       offset2=(MagickOffsetType) (offset + TILE_WIDTH * TILE_WIDTH * 4* 1.5);
 646     /* seek to the tile offset */
 647     offset=SeekBlob(image, offset, SEEK_SET);
 648
 649       /*
 650         Allocate the image for the tile.  NOTE: the last tile in a row or
 651         column may not be a full tile!
 652       */
 653       tile_image_width=(size_t) (destLeft == (int) ntile_cols-1 ?
 654         (int) width % TILE_WIDTH : TILE_WIDTH);
 655       if (tile_image_width == 0)
 656         tile_image_width=TILE_WIDTH;
 657       tile_image_height = (size_t) (destTop == (int) ntile_rows-1 ?
 658         (int) height % TILE_HEIGHT : TILE_HEIGHT);
 659       if (tile_image_height == 0)
 660         tile_image_height=TILE_HEIGHT;
 661       tile_image=CloneImage(inLayerInfo->image,tile_image_width,
 662         tile_image_height,MagickTrue,exception);
 663
 664       /* read in the tile */
 665       switch (inDocInfo->compression)
 666       {
 667         case COMPRESS_NONE:
 668           if (load_tile(image,tile_image,inDocInfo,inLayerInfo,(size_t) (offset2-offset),exception) == 0)
 669             status=MagickTrue;
 670           break;
 671         case COMPRESS_RLE:
 672           if (load_tile_rle (image,tile_image,inDocInfo,inLayerInfo,
 673               (int) (offset2-offset),exception) == 0)
 674             status=MagickTrue;
 675           break;
 676         case COMPRESS_ZLIB:
 677           ThrowBinaryException(CoderError,"ZipCompressNotSupported",
 678             image->filename)
 679         case COMPRESS_FRACTAL:
 680           ThrowBinaryException(CoderError,"FractalCompressNotSupported",
 681             image->filename)
 682       }
 683
 684       /* composite the tile onto the layer's image, and then destroy it */
 685       (void) CompositeImage(inLayerInfo->image,CopyCompositeOp,tile_image,
 686         destLeft * TILE_WIDTH,destTop*TILE_HEIGHT,exception);
 687       tile_image=DestroyImage(tile_image);
 688
 689       /* adjust tile position */
 690       destLeft++;
 691       if (destLeft >= (int) ntile_cols)
 692         {
 693           destLeft = 0;
 694           destTop++;
 695         }
 696       if (status != MagickFalse)
 697         return(MagickFalse);
 698       /* restore the saved position so we'll be ready to
 699        *  read the next offset.
 700        */
 701       offset=SeekBlob(image, saved_pos, SEEK_SET);
 702       /* read in the offset of the next tile */
 703       offset=(MagickOffsetType) ReadBlobMSBLong(image);
 704     }
 705   if (offset != 0)
 706     ThrowBinaryException(CorruptImageError,"CorruptImage",image->filename)
 707   return(MagickTrue);
 708 }
 709
 710 static MagickBooleanType load_hierarchy(Image *image,XCFDocInfo *inDocInfo,
 711    XCFLayerInfo *inLayer)
 712 {
 713   MagickOffsetType
 714     saved_pos,
 715     offset,
 716     junk;
 717
 718   size_t
 719     width,
 720     height,
 721     bytes_per_pixel;
 722
 723   width=ReadBlobMSBLong(image);
 724   (void) width;
 725   height=ReadBlobMSBLong(image);
 726   (void) height;
 727   bytes_per_pixel=inDocInfo->bytes_per_pixel=ReadBlobMSBLong(image);
 728   (void) bytes_per_pixel;
 729
 730   /* load in the levels...we make sure that the number of levels
 731    *  calculated when the TileManager was created is the same
 732    *  as the number of levels found in the file.
 733    */
 734   offset=(MagickOffsetType) ReadBlobMSBLong(image);  /* top level */
 735
 736   /* discard offsets for layers below first, if any.
 737    */
 738   do
 739   {
 740     junk=(MagickOffsetType) ReadBlobMSBLong(image);
 741   }
 742   while (junk != 0);
 743
 744   /* save the current position as it is where the
 745    *  next level offset is stored.
 746    */
 747   saved_pos=TellBlob(image);
 748
 749   /* seek to the level offset */
 750   offset=SeekBlob(image, offset, SEEK_SET);
 751
 752   /* read in the level */
 753   if (load_level (image, inDocInfo, inLayer) == 0)
 754     return(MagickFalse);
 755   /* restore the saved position so we'll be ready to
 756    *  read the next offset.
 757    */
 758   offset=SeekBlob(image, saved_pos, SEEK_SET);
 759   return(MagickTrue);
 760 }
 761
 762 static MagickBooleanType ReadOneLayer(Image* image,XCFDocInfo* inDocInfo,
 763   XCFLayerInfo *outLayer, ExceptionInfo *exception )
 764 {
 765   MagickOffsetType
 766     offset;
 767
 768   unsigned int
 769     foundPropEnd = 0;
 770
 771   size_t
 772     hierarchy_offset,
 773     layer_mask_offset;
 774
 775   /* clear the block! */
 776   (void) ResetMagickMemory( outLayer, 0, sizeof( XCFLayerInfo ) );
 777   /* read in the layer width, height, type and name */
 778   outLayer->width = ReadBlobMSBLong(image);
 779   outLayer->height = ReadBlobMSBLong(image);
 780   outLayer->type = ReadBlobMSBLong(image);
 781   (void) ReadBlobStringWithLongSize(image, outLayer->name,
 782     sizeof(outLayer->name),exception);
 783   /* allocate the image for this layer */
 784   outLayer->image=CloneImage(image,outLayer->width, outLayer->height,MagickTrue,
 785      exception);
 786   if (outLayer->image == (Image *) NULL)
 787     return MagickFalse;
 788   /* read the layer properties! */
 789   foundPropEnd = 0;
 790   while ( (foundPropEnd == MagickFalse) && (EOFBlob(image) == MagickFalse) ) {
 791   PropType    prop_type = (PropType) ReadBlobMSBLong(image);
 792   size_t  prop_size = ReadBlobMSBLong(image);
 793     switch (prop_type)
 794     {
 795     case PROP_END:
 796       foundPropEnd = 1;
 797       break;
 798     case PROP_ACTIVE_LAYER:
 799       outLayer->active = 1;
 800       break;
 801     case PROP_FLOATING_SELECTION:
 802       outLayer->floating_offset = ReadBlobMSBLong(image);
 803       break;
 804     case PROP_OPACITY:
 805       outLayer->alpha = ReadBlobMSBLong(image);
 806       break;
 807     case PROP_VISIBLE:
 808       outLayer->visible = ReadBlobMSBLong(image);
 809       break;
 810     case PROP_LINKED:
 811       outLayer->linked = ReadBlobMSBLong(image);
 812       break;
 813     case PROP_PRESERVE_TRANSPARENCY:
 814       outLayer->preserve_trans = ReadBlobMSBLong(image);
 815       break;
 816     case PROP_APPLY_MASK:
 817       outLayer->apply_mask = ReadBlobMSBLong(image);
 818       break;
 819     case PROP_EDIT_MASK:
 820       outLayer->edit_mask = ReadBlobMSBLong(image);
 821       break;
 822     case PROP_SHOW_MASK:
 823       outLayer->show_mask = ReadBlobMSBLong(image);
 824       break;
 825     case PROP_OFFSETS:
 826       outLayer->offset_x = (int) ReadBlobMSBLong(image);
 827       outLayer->offset_y = (int) ReadBlobMSBLong(image);
 828       break;
 829     case PROP_MODE:
 830       outLayer->mode = ReadBlobMSBLong(image);
 831       break;
 832     case PROP_TATTOO:
 833       outLayer->preserve_trans = ReadBlobMSBLong(image);
 834       break;
 835      case PROP_PARASITES:
 836      {
 837        if (DiscardBlobBytes(image,prop_size) == MagickFalse)
 838          ThrowFileException(exception,CorruptImageError,
 839            "UnexpectedEndOfFile",image->filename);
 840
 841         /*
 842        ssize_t base = info->cp;
 843        GimpParasite *p;
 844        while (info->cp - base < prop_size)
 845        {
 846        p = xcf_load_parasite(info);
 847        gimp_drawable_parasite_attach(GIMP_DRAWABLE(layer), p);
 848        gimp_parasite_free(p);
 849        }
 850        if (info->cp - base != prop_size)
 851        g_message ("Error detected while loading a layer's parasites");
 852        */
 853      }
 854      break;
 855     default:
 856       /* g_message ("unexpected/unknown layer property: %d (skipping)",
 857          prop_type); */
 858
 859       {
 860       int buf[16];
 861       ssize_t amount;
 862
 863       /* read over it... */
 864       while ((prop_size > 0) && (EOFBlob(image) == MagickFalse))
 865         {
 866         amount = (ssize_t) MagickMin(16, prop_size);
 867         amount = ReadBlob(image, (size_t) amount, (unsigned char *) &buf);
 868         if (!amount)
 869           ThrowBinaryException(CorruptImageError,"CorruptImage",
 870             image->filename);
 871         prop_size -= (size_t) MagickMin(16, (size_t) amount);
 872         }
 873       }
 874       break;
 875     }
 876   }
 877
 878   if (foundPropEnd == MagickFalse)
 879     return(MagickFalse);
 880   /* clear the image based on the layer opacity */
 881   outLayer->image->background_color.alpha=
 882     ScaleCharToQuantum((unsigned char) (255-outLayer->alpha));
 883   (void) SetImageBackgroundColor(outLayer->image,exception);
 884
 885   /* set the compositing mode */
 886   outLayer->image->compose = GIMPBlendModeToCompositeOperator( outLayer->mode );
 887   if ( outLayer->visible == MagickFalse )
 888     {
 889       /* BOGUS: should really be separate member var! */
 890       outLayer->image->compose = NoCompositeOp;
 891     }
 892
 893   /* read the hierarchy and layer mask offsets */
 894   hierarchy_offset = ReadBlobMSBLong(image);
 895   layer_mask_offset = ReadBlobMSBLong(image);
 896
 897   /* read in the hierarchy */
 898   offset=SeekBlob(image, (MagickOffsetType) hierarchy_offset, SEEK_SET);
 899   if (offset < 0)
 900     (void) ThrowMagickException(exception,GetMagickModule(),
 901       CorruptImageError,"InvalidImageHeader","`%s'",image->filename);
 902   if (load_hierarchy (image, inDocInfo, outLayer) == 0)
 903     return(MagickFalse);
 904
 905   /* read in the layer mask */
 906   if (layer_mask_offset != 0)
 907     {
 908       offset=SeekBlob(image, (MagickOffsetType) layer_mask_offset, SEEK_SET);
 909
 910 #if 0  /* BOGUS: support layer masks! */
 911       layer_mask = xcf_load_layer_mask (info, gimage);
 912       if (layer_mask == 0)
 913   goto error;
 914
 915       /* set the offsets of the layer_mask */
 916       GIMP_DRAWABLE (layer_mask)->offset_x = GIMP_DRAWABLE (layer)->offset_x;
 917       GIMP_DRAWABLE (layer_mask)->offset_y = GIMP_DRAWABLE (layer)->offset_y;
 918
 919       gimp_layer_add_mask (layer, layer_mask, MagickFalse);
 920
 921       layer->mask->apply_mask = apply_mask;
 922       layer->mask->edit_mask  = edit_mask;
 923       layer->mask->show_mask  = show_mask;
 924 #endif
 925   }
 926
 927   /* attach the floating selection... */
 928 #if 0  /* BOGUS: we may need to read this, even if we don't support it! */
 929   if (add_floating_sel)
 930     {
 931       GimpLayer *floating_sel;
 932
 933       floating_sel = info->floating_sel;
 934       floating_sel_attach (floating_sel, GIMP_DRAWABLE (layer));
 935     }
 936 #endif
 937
 938   return MagickTrue;
 939 }
 940
 941 /*
 942 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 943 %                                                                             %
 944 %                                                                             %
 945 %                                                                             %
 946 %   R e a d X C F I m a g e                                                   %
 947 %                                                                             %
 948 %                                                                             %
 949 %                                                                             %
 950 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 951 %
 952 %  ReadXCFImage() reads a GIMP (GNU Image Manipulation Program) image
 953 %  file and returns it.  It allocates the memory necessary for the new Image
 954 %  structure and returns a pointer to the new image.
 955 %
 956 %  The format of the ReadXCFImage method is:
 957 %
 958 %      image=ReadXCFImage(image_info)
 959 %
 960 %  A description of each parameter follows:
 961 %
 962 %    o image_info: the image info.
 963 %
 964 %    o exception: return any errors or warnings in this structure.
 965 %
 966 %
 967 */
 968 static Image *ReadXCFImage(const ImageInfo *image_info,ExceptionInfo *exception)
 969 {
 970   char
 971     magick[14];
 972
 973   Image
 974     *image;
 975
 976   int
 977     foundPropEnd = 0;
 978
 979   MagickBooleanType
 980     status;
 981
 982   MagickOffsetType
 983     offset;
 984
 985   register ssize_t
 986     i;
 987
 988   size_t
 989     image_type,
 990     length;
 991
 992   ssize_t
 993     count;
 994
 995   XCFDocInfo
 996     doc_info;
 997
 998   /*
 999     Open image file.
1000   */
1001   assert(image_info != (const ImageInfo *) NULL);
1002   assert(image_info->signature == MagickSignature);
1003   if (image_info->debug != MagickFalse)
1004     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
1005       image_info->filename);
1006   assert(exception != (ExceptionInfo *) NULL);
1007   assert(exception->signature == MagickSignature);
1008   image=AcquireImage(image_info,exception);
1009   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
1010   if (status == MagickFalse)
1011     {
1012       image=DestroyImageList(image);
1013       return((Image *) NULL);
1014     }
1015   count=ReadBlob(image,14,(unsigned char *) magick);
1016   if ((count == 0) ||
1017       (LocaleNCompare((char *) magick,"gimp xcf",8) != 0))
1018     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1019   (void) ResetMagickMemory(&doc_info,0,sizeof(XCFDocInfo));
1020   doc_info.exception=exception;
1021   doc_info.width=ReadBlobMSBLong(image);
1022   doc_info.height=ReadBlobMSBLong(image);
1023   if ((doc_info.width > 262144) || (doc_info.height > 262144))
1024     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1025   doc_info.image_type=ReadBlobMSBLong(image);
1026   /*
1027     Initialize image attributes.
1028   */
1029   image->columns=doc_info.width;
1030   image->rows=doc_info.height;
1031   image_type=doc_info.image_type;
1032   doc_info.file_size=GetBlobSize(image);
1033   image->compression=NoCompression;
1034   image->depth=8;
1035   if (image_type == GIMP_RGB)
1036     image->colorspace=RGBColorspace;
1037   else
1038     if (image_type == GIMP_GRAY)
1039       image->colorspace=GRAYColorspace;
1040     else
1041       if (image_type == GIMP_INDEXED)
1042         ThrowReaderException(CoderError,"ColormapTypeNotSupported");
1043   (void) SetImageBackgroundColor(image,exception);
1044   image->matte=MagickTrue;
1045   /*
1046     Read properties.
1047   */
1048   while ((foundPropEnd == MagickFalse) && (EOFBlob(image) == MagickFalse))
1049   {
1050     PropType prop_type = (PropType) ReadBlobMSBLong(image);
1051     size_t prop_size = ReadBlobMSBLong(image);
1052
1053     switch (prop_type)
1054     {
1055       case PROP_END:
1056         foundPropEnd=1;
1057         break;
1058       case PROP_COLORMAP:
1059       {
1060         /* Cannot rely on prop_size here--the value is set incorrectly
1061            by some Gimp versions.
1062         */
1063         size_t num_colours = ReadBlobMSBLong(image);
1064         if (DiscardBlobBytes(image,3*num_colours) == MagickFalse)
1065           ThrowFileException(exception,CorruptImageError,
1066             "UnexpectedEndOfFile",image->filename);
1067     /*
1068       if (info->file_version == 0)
1069       {
1070         gint i;
1071
1072         g_message (_("XCF warning: version 0 of XCF file format\n"
1073            "did not save indexed colormaps correctly.\n"
1074            "Substituting grayscale map."));
1075         info->cp +=
1076           xcf_read_int32 (info->fp, (guint32*) &gimage->num_cols, 1);
1077         gimage->cmap = g_new (guchar, gimage->num_cols*3);
1078         xcf_seek_pos (info, info->cp + gimage->num_cols);
1079         for (i = 0; i<gimage->num_cols; i++)
1080           {
1081             gimage->cmap[i*3+0] = i;
1082             gimage->cmap[i*3+1] = i;
1083             gimage->cmap[i*3+2] = i;
1084           }
1085       }
1086       else
1087       {
1088         info->cp +=
1089           xcf_read_int32 (info->fp, (guint32*) &gimage->num_cols, 1);
1090         gimage->cmap = g_new (guchar, gimage->num_cols*3);
1091         info->cp +=
1092           xcf_read_int8 (info->fp,
1093                    (guint8*) gimage->cmap, gimage->num_cols*3);
1094       }
1095      */
1096         break;
1097       }
1098       case PROP_COMPRESSION:
1099       {
1100         doc_info.compression = ReadBlobByte(image);
1101         if ((doc_info.compression != COMPRESS_NONE) &&
1102             (doc_info.compression != COMPRESS_RLE) &&
1103             (doc_info.compression != COMPRESS_ZLIB) &&
1104             (doc_info.compression != COMPRESS_FRACTAL))
1105           ThrowReaderException(CorruptImageError,"UnrecognizedImageCompression");
1106       }
1107       break;
1108
1109       case PROP_GUIDES:
1110       {
1111          /* just skip it - we don't care about guides */
1112         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1113           ThrowFileException(exception,CorruptImageError,
1114             "UnexpectedEndOfFile",image->filename);
1115       }
1116       break;
1117
1118     case PROP_RESOLUTION:
1119       {
1120         /* float xres = (float) */ (void) ReadBlobMSBLong(image);
1121         /* float yres = (float) */ (void) ReadBlobMSBLong(image);
1122
1123         /*
1124         if (xres < GIMP_MIN_RESOLUTION || xres > GIMP_MAX_RESOLUTION ||
1125             yres < GIMP_MIN_RESOLUTION || yres > GIMP_MAX_RESOLUTION)
1126         {
1127         g_message ("Warning, resolution out of range in XCF file");
1128         xres = gimage->gimp->config->default_xresolution;
1129         yres = gimage->gimp->config->default_yresolution;
1130         }
1131         */
1132
1133
1134         /* BOGUS: we don't write these yet because we aren't
1135               reading them properly yet :(
1136               image->resolution.x = xres;
1137               image->resolution.y = yres;
1138         */
1139       }
1140       break;
1141
1142     case PROP_TATTOO:
1143       {
1144         /* we need to read it, even if we ignore it */
1145         /*size_t  tattoo_state = */ (void) ReadBlobMSBLong(image);
1146       }
1147       break;
1148
1149     case PROP_PARASITES:
1150       {
1151         /* BOGUS: we may need these for IPTC stuff */
1152         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1153           ThrowFileException(exception,CorruptImageError,
1154             "UnexpectedEndOfFile",image->filename);
1155         /*
1156       gssize_t         base = info->cp;
1157       GimpParasite *p;
1158
1159       while (info->cp - base < prop_size)
1160         {
1161           p = xcf_load_parasite (info);
1162           gimp_image_parasite_attach (gimage, p);
1163           gimp_parasite_free (p);
1164         }
1165       if (info->cp - base != prop_size)
1166         g_message ("Error detected while loading an image's parasites");
1167       */
1168           }
1169       break;
1170
1171     case PROP_UNIT:
1172       {
1173         /* BOGUS: ignore for now... */
1174       /*size_t unit =  */ (void) ReadBlobMSBLong(image);
1175       }
1176       break;
1177
1178     case PROP_PATHS:
1179       {
1180       /* BOGUS: just skip it for now */
1181         if (DiscardBlobBytes(image,prop_size) == MagickFalse)
1182           ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
1183             image->filename);
1184
1185         /*
1186       PathList *paths = xcf_load_bzpaths (gimage, info);
1187       gimp_image_set_paths (gimage, paths);
1188       */
1189       }
1190       break;
1191
1192     case PROP_USER_UNIT:
1193       {
1194         char  unit_string[1000];
1195         /*BOGUS: ignored for now */
1196         /*float  factor = (float) */ (void) ReadBlobMSBLong(image);
1197         /* size_t digits =  */ (void) ReadBlobMSBLong(image);
1198         for (i=0; i<5; i++)
1199          (void) ReadBlobStringWithLongSize(image, unit_string,
1200            sizeof(unit_string),exception);
1201       }
1202      break;
1203
1204       default:
1205       {
1206         int buf[16];
1207         ssize_t amount;
1208
1209       /* read over it... */
1210       while ((prop_size > 0) && (EOFBlob(image) == MagickFalse))
1211       {
1212         amount=(ssize_t) MagickMin(16, prop_size);
1213         amount=(ssize_t) ReadBlob(image,(size_t) amount,(unsigned char *) &buf);
1214         if (!amount)
1215           ThrowReaderException(CorruptImageError,"CorruptImage");
1216         prop_size -= (size_t) MagickMin(16,(size_t) amount);
1217       }
1218     }
1219     break;
1220   }
1221   }
1222   if (foundPropEnd == MagickFalse)
1223     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1224
1225   if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
1226     {
1227       ; /* do nothing, were just pinging! */
1228     }
1229   else
1230     {
1231       int
1232         current_layer = 0,
1233         foundAllLayers = MagickFalse,
1234         number_layers = 0;
1235
1236       MagickOffsetType
1237         oldPos=TellBlob(image);
1238
1239       XCFLayerInfo
1240         *layer_info;
1241
1242       /*
1243         the read pointer
1244       */
1245       do
1246       {
1247         ssize_t offset = (int) ReadBlobMSBLong(image);
1248         if (offset == 0)
1249           foundAllLayers=MagickTrue;
1250         else
1251           number_layers++;
1252         if (EOFBlob(image) != MagickFalse)
1253           {
1254             ThrowFileException(exception,CorruptImageError,
1255               "UnexpectedEndOfFile",image->filename);
1256             break;
1257           }
1258     } while (foundAllLayers == MagickFalse);
1259     offset=SeekBlob(image,oldPos,SEEK_SET); /* restore the position! */
1260     if (offset < 0)
1261       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
1262     /* allocate our array of layer info blocks */
1263     length=(size_t) number_layers;
1264     layer_info=(XCFLayerInfo *) AcquireQuantumMemory(length,
1265       sizeof(*layer_info));
1266     if (layer_info == (XCFLayerInfo *) NULL)
1267       ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
1268     (void) ResetMagickMemory(layer_info,0,number_layers*sizeof(XCFLayerInfo));
1269     for ( ; ; )
1270     {
1271       MagickBooleanType
1272         layer_ok;
1273
1274       MagickOffsetType
1275         offset,
1276         saved_pos;
1277
1278       /* read in the offset of the next layer */
1279       offset=(MagickOffsetType) ReadBlobMSBLong(image);
1280       /* if the offset is 0 then we are at the end
1281       *  of the layer list.
1282       */
1283       if (offset == 0)
1284         break;
1285       /* save the current position as it is where the
1286       *  next layer offset is stored.
1287       */
1288       saved_pos=TellBlob(image);
1289       /* seek to the layer offset */
1290       offset=SeekBlob(image,offset,SEEK_SET);
1291       /* read in the layer */
1292       layer_ok=ReadOneLayer(image,&doc_info,&layer_info[current_layer],
1293         exception);
1294       if (layer_ok == MagickFalse)
1295         {
1296           int j;
1297
1298           for (j=0; j < current_layer; j++)
1299             layer_info[j].image=DestroyImage(layer_info[j].image);
1300         ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
1301       }
1302       /* restore the saved position so we'll be ready to
1303       *  read the next offset.
1304       */
1305       offset=SeekBlob(image, saved_pos, SEEK_SET);
1306       current_layer++;
1307     }
1308     if (number_layers == 1)
1309       {
1310         /*
1311           Composite the layer data onto the main image, dispose the layer.
1312         */
1313         (void) CompositeImage(image,OverCompositeOp,layer_info[0].image,
1314           layer_info[0].offset_x,layer_info[0].offset_y,exception);
1315         layer_info[0].image =DestroyImage( layer_info[0].image);
1316       }
1317     else
1318       {
1319 #if 0
1320         {
1321         /* NOTE: XCF layers are REVERSED from composite order! */
1322         signed int  j;
1323         for (j=number_layers-1; j>=0; j--) {
1324           /* BOGUS: need to consider layer blending modes!! */
1325
1326           if ( layer_info[j].visible ) { /* only visible ones, please! */
1327             CompositeImage(image, OverCompositeOp, layer_info[j].image,
1328                      layer_info[j].offset_x, layer_info[j].offset_y );
1329              layer_info[j].image =DestroyImage( layer_info[j].image );
1330
1331             /* Bob says that if we do this, we'll get REAL gray images! */
1332             if ( image_type == GIMP_GRAY ) {
1333               QuantizeInfo  qi;
1334               GetQuantizeInfo(&qi);
1335               qi.colorspace = GRAYColorspace;
1336               QuantizeImage( &qi, layer_info[j].image );
1337             }
1338           }
1339         }
1340       }
1341 #else
1342       {
1343         /* NOTE: XCF layers are REVERSED from composite order! */
1344         signed int  j;
1345
1346         /* first we copy the last layer on top of the main image */
1347         (void) CompositeImage(image,CopyCompositeOp,
1348           layer_info[number_layers-1].image,
1349           layer_info[number_layers-1].offset_x,
1350           layer_info[number_layers-1].offset_y,exception);
1351           layer_info[number_layers-1].image=DestroyImage(
1352             layer_info[number_layers-1].image);
1353
1354         /* now reverse the order of the layers as they are put
1355            into subimages
1356         */
1357         j=number_layers-2;
1358         image->next=layer_info[j].image;
1359         layer_info[j].image->previous=image;
1360         layer_info[j].image->page.x=layer_info[j].offset_x;
1361         layer_info[j].image->page.y=layer_info[j].offset_y;
1362         layer_info[j].image->page.width=layer_info[j].width;
1363         layer_info[j].image->page.height=layer_info[j].height;
1364         for (j=number_layers-3; j>=0; j--)
1365         {
1366           if (j > 0)
1367             layer_info[j].image->next=layer_info[j-1].image;
1368           if (j < (number_layers-1))
1369             layer_info[j].image->previous=layer_info[j+1].image;
1370           layer_info[j].image->page.x=layer_info[j].offset_x;
1371           layer_info[j].image->page.y=layer_info[j].offset_y;
1372           layer_info[j].image->page.width=layer_info[j].width;
1373           layer_info[j].image->page.height=layer_info[j].height;
1374         }
1375       }
1376 #endif
1377     }
1378
1379     layer_info=(XCFLayerInfo *) RelinquishMagickMemory(layer_info);
1380
1381 #if 0  /* BOGUS: do we need the channels?? */
1382     while (MagickTrue)
1383     {
1384       /* read in the offset of the next channel */
1385       info->cp += xcf_read_int32 (info->fp, &offset, 1);
1386
1387       /* if the offset is 0 then we are at the end
1388       *  of the channel list.
1389       */
1390       if (offset == 0)
1391         break;
1392
1393       /* save the current position as it is where the
1394       *  next channel offset is stored.
1395       */
1396       saved_pos = info->cp;
1397
1398       /* seek to the channel offset */
1399       xcf_seek_pos (info, offset);
1400
1401       /* read in the layer */
1402       channel = xcf_load_channel (info, gimage);
1403       if (channel == 0)
1404         goto error;
1405
1406       num_successful_elements++;
1407
1408       /* add the channel to the image if its not the selection */
1409       if (channel != gimage->selection_mask)
1410         gimp_image_add_channel (gimage, channel, -1);
1411
1412       /* restore the saved position so we'll be ready to
1413       *  read the next offset.
1414       */
1415       xcf_seek_pos (info, saved_pos);
1416     }
1417 #endif
1418   }
1419
1420   (void) CloseBlob(image);
1421   if (image_type == GIMP_GRAY)
1422     image->type=GrayscaleType;
1423   return(GetFirstImageInList(image));
1424 }
1425 \f
1426 /*
1427 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1428 %                                                                             %
1429 %                                                                             %
1430 %                                                                             %
1431 %   R e g i s t e r X C F I m a g e                                           %
1432 %                                                                             %
1433 %                                                                             %
1434 %                                                                             %
1435 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1436 %
1437 %  RegisterXCFImage() adds attributes for the XCF image format to
1438 %  the list of supported formats.  The attributes include the image format
1439 %  tag, a method to read and/or write the format, whether the format
1440 %  supports the saving of more than one frame to the same file or blob,
1441 %  whether the format supports native in-memory I/O, and a brief
1442 %  description of the format.
1443 %
1444 %  The format of the RegisterXCFImage method is:
1445 %
1446 %      size_t RegisterXCFImage(void)
1447 %
1448 */
1449 ModuleExport size_t RegisterXCFImage(void)
1450 {
1451   MagickInfo
1452     *entry;
1453
1454   entry=SetMagickInfo("XCF");
1455   entry->decoder=(DecodeImageHandler *) ReadXCFImage;
1456   entry->magick=(IsImageFormatHandler *) IsXCF;
1457   entry->description=ConstantString("GIMP image");
1458   entry->module=ConstantString("XCF");
1459   entry->seekable_stream=MagickTrue;
1460   (void) RegisterMagickInfo(entry);
1461   return(MagickImageCoderSignature);
1462 }
1463 \f
1464 /*
1465 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1466 %                                                                             %
1467 %                                                                             %
1468 %                                                                             %
1469 %   U n r e g i s t e r X C F I m a g e                                       %
1470 %                                                                             %
1471 %                                                                             %
1472 %                                                                             %
1473 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1474 %
1475 %  UnregisterXCFImage() removes format registrations made by the
1476 %  XCF module from the list of supported formats.
1477 %
1478 %  The format of the UnregisterXCFImage method is:
1479 %
1480 %      UnregisterXCFImage(void)
1481 %
1482 */
1483 ModuleExport void UnregisterXCFImage(void)
1484 {
1485   (void) UnregisterMagickInfo("XCF");
1486 }