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 1999-2013 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/attribute.h"
  44 #include "MagickCore/blob.h"
  45 #include "MagickCore/blob-private.h"
  46 #include "MagickCore/cache.h"
  47 #include "MagickCore/colorspace.h"
  48 #include "MagickCore/colorspace-private.h"
  49 #include "MagickCore/constitute.h"
  50 #include "MagickCore/exception.h"
  51 #include "MagickCore/exception-private.h"
  52 #include "MagickCore/image.h"
  53 #include "MagickCore/image-private.h"
  54 #include "MagickCore/list.h"
  55 #include "MagickCore/magick.h"
  56 #include "MagickCore/memory_.h"
  57 #include "MagickCore/monitor.h"
  58 #include "MagickCore/monitor-private.h"
  59 #include "MagickCore/pixel.h"
  60 #include "MagickCore/pixel-accessor.h"
  61 #include "MagickCore/quantum-private.h"
  62 #include "MagickCore/static.h"
  63 #include "MagickCore/statistic.h"
  64 #include "MagickCore/string_.h"
  65 #include "MagickCore/module.h"
  66 \f
  67 /*
  68   Forward declarations.
  69 */
  70 static MagickBooleanType
  71   WriteGRAYImage(const ImageInfo *,Image *,ExceptionInfo *);
  72 \f
  73 /*
  74 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  75 %                                                                             %
  76 %                                                                             %
  77 %                                                                             %
  78 %   R e a d G R A Y I m a g e                                                 %
  79 %                                                                             %
  80 %                                                                             %
  81 %                                                                             %
  82 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  83 %
  84 %  ReadGRAYImage() reads an image of raw grayscale samples and returns
  85 %  it.  It allocates the memory necessary for the new Image structure and
  86 %  returns a pointer to the new image.
  87 %
  88 %  The format of the ReadGRAYImage method is:
  89 %
  90 %      Image *ReadGRAYImage(const ImageInfo *image_info,
  91 %        ExceptionInfo *exception)
  92 %
  93 %  A description of each parameter follows:
  94 %
  95 %    o image_info: the image info.
  96 %
  97 %    o exception: return any errors or warnings in this structure.
  98 %
  99 */
 100 static Image *ReadGRAYImage(const ImageInfo *image_info,
 101   ExceptionInfo *exception)
 102 {
 103   Image
 104     *canvas_image,
 105     *image;
 106
 107   MagickBooleanType
 108     status;
 109
 110   MagickOffsetType
 111     scene;
 112
 113   QuantumInfo
 114     *quantum_info;
 115
 116   QuantumType
 117     quantum_type;
 118
 119   size_t
 120     length;
 121
 122   ssize_t
 123     count,
 124     y;
 125
 126   unsigned char
 127     *pixels;
 128
 129   /*
 130     Open image file.
 131   */
 132   assert(image_info != (const ImageInfo *) NULL);
 133   assert(image_info->signature == MagickSignature);
 134   if (image_info->debug != MagickFalse)
 135     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
 136       image_info->filename);
 137   assert(exception != (ExceptionInfo *) NULL);
 138   assert(exception->signature == MagickSignature);
 139   image=AcquireImage(image_info,exception);
 140   if ((image->columns == 0) || (image->rows == 0))
 141     ThrowReaderException(OptionError,"MustSpecifyImageSize");
 142   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
 143   if (status == MagickFalse)
 144     {
 145       image=DestroyImageList(image);
 146       return((Image *) NULL);
 147     }
 148   if (DiscardBlobBytes(image,(size_t) image->offset) == MagickFalse)
 149     ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
 150       image->filename);
 151   /*
 152     Create virtual canvas to support cropping (i.e. image.gray[100x100+10+20]).
 153   */
 154   SetImageColorspace(image,GRAYColorspace,exception);
 155   canvas_image=CloneImage(image,image->extract_info.width,1,MagickFalse,
 156     exception);
 157   (void) SetImageVirtualPixelMethod(canvas_image,BlackVirtualPixelMethod,
 158     exception);
 159   quantum_type=GrayQuantum;
 160   quantum_info=AcquireQuantumInfo(image_info,canvas_image);
 161   if (quantum_info == (QuantumInfo *) NULL)
 162     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
 163   pixels=GetQuantumPixels(quantum_info);
 164   if (image_info->number_scenes != 0)
 165     while (image->scene < image_info->scene)
 166     {
 167       /*
 168         Skip to next image.
 169       */
 170       image->scene++;
 171       length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 172       for (y=0; y < (ssize_t) image->rows; y++)
 173       {
 174         count=ReadBlob(image,length,pixels);
 175         if (count != (ssize_t) length)
 176           break;
 177       }
 178     }
 179   scene=0;
 180   count=0;
 181   length=0;
 182   do
 183   {
 184     /*
 185       Read pixels to virtual canvas image then push to image.
 186     */
 187     if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
 188       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 189         break;
 190     SetImageColorspace(image,GRAYColorspace,exception);
 191     if (scene == 0)
 192       {
 193         length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 194         count=ReadBlob(image,length,pixels);
 195       }
 196     for (y=0; y < (ssize_t) image->extract_info.height; y++)
 197     {
 198       register const Quantum
 199         *restrict p;
 200
 201       register ssize_t
 202         x;
 203
 204       register Quantum
 205         *restrict q;
 206
 207       if (count != (ssize_t) length)
 208         {
 209           ThrowFileException(exception,CorruptImageError,
 210             "UnexpectedEndOfFile",image->filename);
 211           break;
 212         }
 213       q=GetAuthenticPixels(canvas_image,0,0,canvas_image->columns,1,exception);
 214       if (q == (Quantum *) NULL)
 215         break;
 216       length=ImportQuantumPixels(canvas_image,(CacheView *) NULL,quantum_info,
 217         quantum_type,pixels,exception);
 218       if (SyncAuthenticPixels(canvas_image,exception) == MagickFalse)
 219         break;
 220       if (((y-image->extract_info.y) >= 0) &&
 221           ((y-image->extract_info.y) < (ssize_t) image->rows))
 222         {
 223           p=GetVirtualPixels(canvas_image,canvas_image->extract_info.x,0,
 224             image->columns,1,exception);
 225           q=QueueAuthenticPixels(image,0,y-image->extract_info.y,image->columns,
 226             1,exception);
 227           if ((p == (const Quantum *) NULL) ||
 228               (q == (Quantum *) NULL))
 229             break;
 230           for (x=0; x < (ssize_t) image->columns; x++)
 231           {
 232             SetPixelGray(image,GetPixelGray(canvas_image,p),q);
 233             p+=GetPixelChannels(canvas_image);
 234             q+=GetPixelChannels(image);
 235           }
 236           if (SyncAuthenticPixels(image,exception) == MagickFalse)
 237             break;
 238         }
 239       if (image->previous == (Image *) NULL)
 240         {
 241           status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
 242             image->rows);
 243           if (status == MagickFalse)
 244             break;
 245         }
 246       count=ReadBlob(image,length,pixels);
 247     }
 248     SetQuantumImageType(image,quantum_type);
 249     /*
 250       Proceed to next image.
 251     */
 252     if (image_info->number_scenes != 0)
 253       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 254         break;
 255     if (count == (ssize_t) length)
 256       {
 257         /*
 258           Allocate next image structure.
 259         */
 260         AcquireNextImage(image_info,image,exception);
 261         if (GetNextImageInList(image) == (Image *) NULL)
 262           {
 263             image=DestroyImageList(image);
 264             return((Image *) NULL);
 265           }
 266         image=SyncNextImageInList(image);
 267         status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
 268           GetBlobSize(image));
 269         if (status == MagickFalse)
 270           break;
 271       }
 272     scene++;
 273   } while (count == (ssize_t) length);
 274   quantum_info=DestroyQuantumInfo(quantum_info);
 275   canvas_image=DestroyImage(canvas_image);
 276   (void) CloseBlob(image);
 277   return(GetFirstImageInList(image));
 278 }
 279 \f
 280 /*
 281 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 282 %                                                                             %
 283 %                                                                             %
 284 %                                                                             %
 285 %   R e g i s t e r G R A Y I m a g e                                         %
 286 %                                                                             %
 287 %                                                                             %
 288 %                                                                             %
 289 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 290 %
 291 %  RegisterGRAYImage() adds attributes for the GRAY image format to
 292 %  the list of supported formats.  The attributes include the image format
 293 %  tag, a method to read and/or write the format, whether the format
 294 %  supports the saving of more than one frame to the same file or blob,
 295 %  whether the format supports native in-memory I/O, and a brief
 296 %  description of the format.
 297 %
 298 %  The format of the RegisterGRAYImage method is:
 299 %
 300 %      size_t RegisterGRAYImage(void)
 301 %
 302 */
 303 ModuleExport size_t RegisterGRAYImage(void)
 304 {
 305   MagickInfo
 306     *entry;
 307
 308   entry=SetMagickInfo("GRAY");
 309   entry->decoder=(DecodeImageHandler *) ReadGRAYImage;
 310   entry->encoder=(EncodeImageHandler *) WriteGRAYImage;
 311   entry->raw=MagickTrue;
 312   entry->endian_support=MagickTrue;
 313   entry->description=ConstantString("Raw gray samples");
 314   entry->module=ConstantString("GRAY");
 315   (void) RegisterMagickInfo(entry);
 316   return(MagickImageCoderSignature);
 317 }
 318 \f
 319 /*
 320 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 321 %                                                                             %
 322 %                                                                             %
 323 %                                                                             %
 324 %   U n r e g i s t e r G R A Y I m a g e                                     %
 325 %                                                                             %
 326 %                                                                             %
 327 %                                                                             %
 328 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 329 %
 330 %  UnregisterGRAYImage() removes format registrations made by the
 331 %  GRAY module from the list of supported formats.
 332 %
 333 %  The format of the UnregisterGRAYImage method is:
 334 %
 335 %      UnregisterGRAYImage(void)
 336 %
 337 */
 338 ModuleExport void UnregisterGRAYImage(void)
 339 {
 340   (void) UnregisterMagickInfo("GRAY");
 341 }
 342 \f
 343 /*
 344 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 345 %                                                                             %
 346 %                                                                             %
 347 %                                                                             %
 348 %   W r i t e G R A Y I m a g e                                               %
 349 %                                                                             %
 350 %                                                                             %
 351 %                                                                             %
 352 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 353 %
 354 %  WriteGRAYImage() writes an image to a file as gray scale intensity
 355 %  values.
 356 %
 357 %  The format of the WriteGRAYImage method is:
 358 %
 359 %      MagickBooleanType WriteGRAYImage(const ImageInfo *image_info,
 360 %        Image *image,ExceptionInfo *exception)
 361 %
 362 %  A description of each parameter follows.
 363 %
 364 %    o image_info: the image info.
 365 %
 366 %    o image:  The image.
 367 %
 368 %    o exception: return any errors or warnings in this structure.
 369 %
 370 */
 371 static MagickBooleanType WriteGRAYImage(const ImageInfo *image_info,
 372   Image *image,ExceptionInfo *exception)
 373 {
 374   MagickBooleanType
 375     status;
 376
 377   MagickOffsetType
 378     scene;
 379
 380   QuantumInfo
 381     *quantum_info;
 382
 383   QuantumType
 384     quantum_type;
 385
 386   size_t
 387     length;
 388
 389   ssize_t
 390     count,
 391     y;
 392
 393   unsigned char
 394     *pixels;
 395
 396   /*
 397     Open output image file.
 398   */
 399   assert(image_info != (const ImageInfo *) NULL);
 400   assert(image_info->signature == MagickSignature);
 401   assert(image != (Image *) NULL);
 402   assert(image->signature == MagickSignature);
 403   if (image->debug != MagickFalse)
 404     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 405   assert(exception != (ExceptionInfo *) NULL);
 406   assert(exception->signature == MagickSignature);
 407   status=OpenBlob(image_info,image,WriteBinaryBlobMode,exception);
 408   if (status == MagickFalse)
 409     return(status);
 410   scene=0;
 411   do
 412   {
 413     /*
 414       Write grayscale pixels.
 415     */
 416     if (IssRGBCompatibleColorspace(image->colorspace) == MagickFalse)
 417       (void) TransformImageColorspace(image,sRGBColorspace,exception);
 418     quantum_type=GrayQuantum;
 419     quantum_info=AcquireQuantumInfo(image_info,image);
 420     if (quantum_info == (QuantumInfo *) NULL)
 421       ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
 422     pixels=GetQuantumPixels(quantum_info);
 423     for (y=0; y < (ssize_t) image->rows; y++)
 424     {
 425       register const Quantum
 426         *restrict p;
 427
 428       p=GetVirtualPixels(image,0,y,image->columns,1,exception);
 429       if (p == (const Quantum *) NULL)
 430         break;
 431       length=ExportQuantumPixels(image,(CacheView *) NULL,quantum_info,
 432         quantum_type,pixels,exception);
 433       count=WriteBlob(image,length,pixels);
 434       if (count != (ssize_t) length)
 435         break;
 436       if (image->previous == (Image *) NULL)
 437         {
 438           status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
 439             image->rows);
 440           if (status == MagickFalse)
 441             break;
 442         }
 443     }
 444     quantum_info=DestroyQuantumInfo(quantum_info);
 445     if (GetNextImageInList(image) == (Image *) NULL)
 446       break;
 447     image=SyncNextImageInList(image);
 448     status=SetImageProgress(image,SaveImagesTag,scene++,
 449       GetImageListLength(image));
 450     if (status == MagickFalse)
 451       break;
 452   } while (image_info->adjoin != MagickFalse);
 453   (void) CloseBlob(image);
 454   return(MagickTrue);
 455 }