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

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %                         GGGG  RRRR    AAA   Y   Y                           %
   7 %                        G      R   R  A   A   Y Y                            %
   8 %                        G  GG  RRRR   AAAAA    Y                             %
   9 %                        G   G  R R    A   A    Y                             %
  10 %                         GGG   R  R   A   A    Y                             %
  11 %                                                                             %
  12 %                                                                             %
  13 %                    Read/Write RAW Gray Image Format                         %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                                John Cristy                                  %
  17 %                                 July 1992                                   %
  18 %                                                                             %
  19 %                                                                             %
  20 %  Copyright 1999-2011 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/colorspace.h"
  47 #include "MagickCore/constitute.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/monitor.h"
  56 #include "MagickCore/monitor-private.h"
  57 #include "MagickCore/pixel.h"
  58 #include "MagickCore/pixel-accessor.h"
  59 #include "MagickCore/quantum-private.h"
  60 #include "MagickCore/static.h"
  61 #include "MagickCore/statistic.h"
  62 #include "MagickCore/string_.h"
  63 #include "MagickCore/module.h"
  64 \f
  65 /*
  66   Forward declarations.
  67 */
  68 static MagickBooleanType
  69   WriteGRAYImage(const ImageInfo *,Image *);
  70 \f
  71 /*
  72 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  73 %                                                                             %
  74 %                                                                             %
  75 %                                                                             %
  76 %   R e a d G R A Y I m a g e                                                 %
  77 %                                                                             %
  78 %                                                                             %
  79 %                                                                             %
  80 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  81 %
  82 %  ReadGRAYImage() reads an image of raw grayscale samples and returns
  83 %  it.  It allocates the memory necessary for the new Image structure and
  84 %  returns a pointer to the new image.
  85 %
  86 %  The format of the ReadGRAYImage method is:
  87 %
  88 %      Image *ReadGRAYImage(const ImageInfo *image_info,
  89 %        ExceptionInfo *exception)
  90 %
  91 %  A description of each parameter follows:
  92 %
  93 %    o image_info: the image info.
  94 %
  95 %    o exception: return any errors or warnings in this structure.
  96 %
  97 */
  98 static Image *ReadGRAYImage(const ImageInfo *image_info,
  99   ExceptionInfo *exception)
 100 {
 101   Image
 102     *canvas_image,
 103     *image;
 104
 105   MagickBooleanType
 106     status;
 107
 108   MagickOffsetType
 109     scene;
 110
 111   QuantumInfo
 112     *quantum_info;
 113
 114   QuantumType
 115     quantum_type;
 116
 117   size_t
 118     length;
 119
 120   ssize_t
 121     count,
 122     y;
 123
 124   unsigned char
 125     *pixels;
 126
 127   /*
 128     Open image file.
 129   */
 130   assert(image_info != (const ImageInfo *) NULL);
 131   assert(image_info->signature == MagickSignature);
 132   if (image_info->debug != MagickFalse)
 133     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
 134       image_info->filename);
 135   assert(exception != (ExceptionInfo *) NULL);
 136   assert(exception->signature == MagickSignature);
 137   image=AcquireImage(image_info);
 138   if ((image->columns == 0) || (image->rows == 0))
 139     ThrowReaderException(OptionError,"MustSpecifyImageSize");
 140   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
 141   if (status == MagickFalse)
 142     {
 143       image=DestroyImageList(image);
 144       return((Image *) NULL);
 145     }
 146   if (DiscardBlobBytes(image,(size_t) image->offset) == MagickFalse)
 147     ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
 148       image->filename);
 149   /*
 150     Create virtual canvas to support cropping (i.e. image.gray[100x100+10+20]).
 151   */
 152   canvas_image=CloneImage(image,image->extract_info.width,1,MagickFalse,
 153     exception);
 154   (void) SetImageVirtualPixelMethod(canvas_image,BlackVirtualPixelMethod);
 155   quantum_type=GrayQuantum;
 156   quantum_info=AcquireQuantumInfo(image_info,canvas_image);
 157   if (quantum_info == (QuantumInfo *) NULL)
 158     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
 159   pixels=GetQuantumPixels(quantum_info);
 160   if (image_info->number_scenes != 0)
 161     while (image->scene < image_info->scene)
 162     {
 163       /*
 164         Skip to next image.
 165       */
 166       image->scene++;
 167       length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 168       for (y=0; y < (ssize_t) image->rows; y++)
 169       {
 170         count=ReadBlob(image,length,pixels);
 171         if (count != (ssize_t) length)
 172           break;
 173       }
 174     }
 175   scene=0;
 176   count=0;
 177   length=0;
 178   do
 179   {
 180     /*
 181       Read pixels to virtual canvas image then push to image.
 182     */
 183     if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
 184       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 185         break;
 186     if (scene == 0)
 187       {
 188         length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 189         count=ReadBlob(image,length,pixels);
 190       }
 191     for (y=0; y < (ssize_t) image->extract_info.height; y++)
 192     {
 193       register const Quantum
 194         *restrict p;
 195
 196       register ssize_t
 197         x;
 198
 199       register Quantum
 200         *restrict q;
 201
 202       if (count != (ssize_t) length)
 203         {
 204           ThrowFileException(exception,CorruptImageError,
 205             "UnexpectedEndOfFile",image->filename);
 206           break;
 207         }
 208       q=GetAuthenticPixels(canvas_image,0,0,canvas_image->columns,1,exception);
 209       if (q == (const Quantum *) NULL)
 210         break;
 211       length=ImportQuantumPixels(canvas_image,(CacheView *) NULL,quantum_info,
 212         quantum_type,pixels,exception);
 213       if (SyncAuthenticPixels(canvas_image,exception) == MagickFalse)
 214         break;
 215       if (((y-image->extract_info.y) >= 0) &&
 216           ((y-image->extract_info.y) < (ssize_t) image->rows))
 217         {
 218           p=GetVirtualPixels(canvas_image,canvas_image->extract_info.x,0,
 219             image->columns,1,exception);
 220           q=QueueAuthenticPixels(image,0,y-image->extract_info.y,image->columns,
 221             1,exception);
 222           if ((p == (const Quantum *) NULL) ||
 223               (q == (const Quantum *) NULL))
 224             break;
 225           for (x=0; x < (ssize_t) image->columns; x++)
 226           {
 227             SetPixelRed(image,GetPixelRed(canvas_image,p),q);
 228             SetPixelGreen(image,GetPixelGreen(canvas_image,p),q);
 229             SetPixelBlue(image,GetPixelBlue(canvas_image,p),q);
 230             p+=GetPixelChannels(canvas_image);
 231             q+=GetPixelChannels(image);
 232           }
 233           if (SyncAuthenticPixels(image,exception) == MagickFalse)
 234             break;
 235         }
 236       if (image->previous == (Image *) NULL)
 237         {
 238           status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
 239             image->rows);
 240           if (status == MagickFalse)
 241             break;
 242         }
 243       count=ReadBlob(image,length,pixels);
 244     }
 245     SetQuantumImageType(image,quantum_type);
 246     /*
 247       Proceed to next image.
 248     */
 249     if (image_info->number_scenes != 0)
 250       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 251         break;
 252     if (count == (ssize_t) length)
 253       {
 254         /*
 255           Allocate next image structure.
 256         */
 257         AcquireNextImage(image_info,image);
 258         if (GetNextImageInList(image) == (Image *) NULL)
 259           {
 260             image=DestroyImageList(image);
 261             return((Image *) NULL);
 262           }
 263         image=SyncNextImageInList(image);
 264         status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
 265           GetBlobSize(image));
 266         if (status == MagickFalse)
 267           break;
 268       }
 269     scene++;
 270   } while (count == (ssize_t) length);
 271   quantum_info=DestroyQuantumInfo(quantum_info);
 272   InheritException(&image->exception,&canvas_image->exception);
 273   canvas_image=DestroyImage(canvas_image);
 274   (void) CloseBlob(image);
 275   return(GetFirstImageInList(image));
 276 }
 277 \f
 278 /*
 279 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 280 %                                                                             %
 281 %                                                                             %
 282 %                                                                             %
 283 %   R e g i s t e r G R A Y I m a g e                                         %
 284 %                                                                             %
 285 %                                                                             %
 286 %                                                                             %
 287 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 288 %
 289 %  RegisterGRAYImage() adds attributes for the GRAY image format to
 290 %  the list of supported formats.  The attributes include the image format
 291 %  tag, a method to read and/or write the format, whether the format
 292 %  supports the saving of more than one frame to the same file or blob,
 293 %  whether the format supports native in-memory I/O, and a brief
 294 %  description of the format.
 295 %
 296 %  The format of the RegisterGRAYImage method is:
 297 %
 298 %      size_t RegisterGRAYImage(void)
 299 %
 300 */
 301 ModuleExport size_t RegisterGRAYImage(void)
 302 {
 303   MagickInfo
 304     *entry;
 305
 306   entry=SetMagickInfo("GRAY");
 307   entry->decoder=(DecodeImageHandler *) ReadGRAYImage;
 308   entry->encoder=(EncodeImageHandler *) WriteGRAYImage;
 309   entry->raw=MagickTrue;
 310   entry->endian_support=MagickTrue;
 311   entry->description=ConstantString("Raw gray samples");
 312   entry->module=ConstantString("GRAY");
 313   (void) RegisterMagickInfo(entry);
 314   return(MagickImageCoderSignature);
 315 }
 316 \f
 317 /*
 318 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 319 %                                                                             %
 320 %                                                                             %
 321 %                                                                             %
 322 %   U n r e g i s t e r G R A Y I m a g e                                     %
 323 %                                                                             %
 324 %                                                                             %
 325 %                                                                             %
 326 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 327 %
 328 %  UnregisterGRAYImage() removes format registrations made by the
 329 %  GRAY module from the list of supported formats.
 330 %
 331 %  The format of the UnregisterGRAYImage method is:
 332 %
 333 %      UnregisterGRAYImage(void)
 334 %
 335 */
 336 ModuleExport void UnregisterGRAYImage(void)
 337 {
 338   (void) UnregisterMagickInfo("GRAY");
 339 }
 340 \f
 341 /*
 342 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 343 %                                                                             %
 344 %                                                                             %
 345 %                                                                             %
 346 %   W r i t e G R A Y I m a g e                                               %
 347 %                                                                             %
 348 %                                                                             %
 349 %                                                                             %
 350 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 351 %
 352 %  WriteGRAYImage() writes an image to a file as gray scale intensity
 353 %  values.
 354 %
 355 %  The format of the WriteGRAYImage method is:
 356 %
 357 %      MagickBooleanType WriteGRAYImage(const ImageInfo *image_info,
 358 %        Image *image)
 359 %
 360 %  A description of each parameter follows.
 361 %
 362 %    o image_info: the image info.
 363 %
 364 %    o image:  The image.
 365 %
 366 */
 367 static MagickBooleanType WriteGRAYImage(const ImageInfo *image_info,
 368   Image *image)
 369 {
 370   MagickBooleanType
 371     status;
 372
 373   MagickOffsetType
 374     scene;
 375
 376   QuantumInfo
 377     *quantum_info;
 378
 379   QuantumType
 380     quantum_type;
 381
 382   size_t
 383     length;
 384
 385   ssize_t
 386     count,
 387     y;
 388
 389   unsigned char
 390     *pixels;
 391
 392   /*
 393     Open output image file.
 394   */
 395   assert(image_info != (const ImageInfo *) NULL);
 396   assert(image_info->signature == MagickSignature);
 397   assert(image != (Image *) NULL);
 398   assert(image->signature == MagickSignature);
 399   if (image->debug != MagickFalse)
 400     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 401   status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
 402   if (status == MagickFalse)
 403     return(status);
 404   scene=0;
 405   do
 406   {
 407     /*
 408       Write grayscale pixels.
 409     */
 410     if (image->colorspace != RGBColorspace)
 411       (void) TransformImageColorspace(image,RGBColorspace);
 412     quantum_type=GrayQuantum;
 413     quantum_info=AcquireQuantumInfo(image_info,image);
 414     if (quantum_info == (QuantumInfo *) NULL)
 415       ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
 416     pixels=GetQuantumPixels(quantum_info);
 417     for (y=0; y < (ssize_t) image->rows; y++)
 418     {
 419       register const Quantum
 420         *restrict p;
 421
 422       p=GetVirtualPixels(image,0,y,image->columns,1,&image->exception);
 423       if (p == (const Quantum *) NULL)
 424         break;
 425       length=ExportQuantumPixels(image,(CacheView *) NULL,quantum_info,
 426         quantum_type,pixels,&image->exception);
 427       count=WriteBlob(image,length,pixels);
 428       if (count != (ssize_t) length)
 429         break;
 430       if (image->previous == (Image *) NULL)
 431         {
 432           status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
 433             image->rows);
 434           if (status == MagickFalse)
 435             break;
 436         }
 437     }
 438     quantum_info=DestroyQuantumInfo(quantum_info);
 439     if (GetNextImageInList(image) == (Image *) NULL)
 440       break;
 441     image=SyncNextImageInList(image);
 442     status=SetImageProgress(image,SaveImagesTag,scene++,
 443       GetImageListLength(image));
 444     if (status == MagickFalse)
 445       break;
 446   } while (image_info->adjoin != MagickFalse);
 447   (void) CloseBlob(image);
 448   return(MagickTrue);
 449 }