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 1999-2012 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/colorspace.h"
  47 #include "MagickCore/colorspace-private.h"
  48 #include "MagickCore/constitute.h"
  49 #include "MagickCore/exception.h"
  50 #include "MagickCore/exception-private.h"
  51 #include "MagickCore/image.h"
  52 #include "MagickCore/image-private.h"
  53 #include "MagickCore/list.h"
  54 #include "MagickCore/magick.h"
  55 #include "MagickCore/memory_.h"
  56 #include "MagickCore/monitor.h"
  57 #include "MagickCore/monitor-private.h"
  58 #include "MagickCore/pixel.h"
  59 #include "MagickCore/pixel-accessor.h"
  60 #include "MagickCore/quantum-private.h"
  61 #include "MagickCore/static.h"
  62 #include "MagickCore/statistic.h"
  63 #include "MagickCore/string_.h"
  64 #include "MagickCore/module.h"
  65 \f
  66 /*
  67   Forward declarations.
  68 */
  69 static MagickBooleanType
  70   WriteGRAYImage(const ImageInfo *,Image *,ExceptionInfo *);
  71 \f
  72 /*
  73 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  74 %                                                                             %
  75 %                                                                             %
  76 %                                                                             %
  77 %   R e a d G R A Y I m a g e                                                 %
  78 %                                                                             %
  79 %                                                                             %
  80 %                                                                             %
  81 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  82 %
  83 %  ReadGRAYImage() reads an image of raw grayscale samples and returns
  84 %  it.  It allocates the memory necessary for the new Image structure and
  85 %  returns a pointer to the new image.
  86 %
  87 %  The format of the ReadGRAYImage method is:
  88 %
  89 %      Image *ReadGRAYImage(const ImageInfo *image_info,
  90 %        ExceptionInfo *exception)
  91 %
  92 %  A description of each parameter follows:
  93 %
  94 %    o image_info: the image info.
  95 %
  96 %    o exception: return any errors or warnings in this structure.
  97 %
  98 */
  99 static Image *ReadGRAYImage(const ImageInfo *image_info,
 100   ExceptionInfo *exception)
 101 {
 102   Image
 103     *canvas_image,
 104     *image;
 105
 106   MagickBooleanType
 107     status;
 108
 109   MagickOffsetType
 110     scene;
 111
 112   QuantumInfo
 113     *quantum_info;
 114
 115   QuantumType
 116     quantum_type;
 117
 118   size_t
 119     length;
 120
 121   ssize_t
 122     count,
 123     y;
 124
 125   unsigned char
 126     *pixels;
 127
 128   /*
 129     Open image file.
 130   */
 131   assert(image_info != (const ImageInfo *) NULL);
 132   assert(image_info->signature == MagickSignature);
 133   if (image_info->debug != MagickFalse)
 134     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
 135       image_info->filename);
 136   assert(exception != (ExceptionInfo *) NULL);
 137   assert(exception->signature == MagickSignature);
 138   image=AcquireImage(image_info,exception);
 139   if ((image->columns == 0) || (image->rows == 0))
 140     ThrowReaderException(OptionError,"MustSpecifyImageSize");
 141   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
 142   if (status == MagickFalse)
 143     {
 144       image=DestroyImageList(image);
 145       return((Image *) NULL);
 146     }
 147   if (DiscardBlobBytes(image,(size_t) image->offset) == MagickFalse)
 148     ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
 149       image->filename);
 150   /*
 151     Create virtual canvas to support cropping (i.e. image.gray[100x100+10+20]).
 152   */
 153   image->colorspace=GRAYColorspace;
 154   canvas_image=CloneImage(image,image->extract_info.width,1,MagickFalse,
 155     exception);
 156   (void) SetImageVirtualPixelMethod(canvas_image,BlackVirtualPixelMethod,
 157     exception);
 158   quantum_type=GrayQuantum;
 159   quantum_info=AcquireQuantumInfo(image_info,canvas_image);
 160   if (quantum_info == (QuantumInfo *) NULL)
 161     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
 162   pixels=GetQuantumPixels(quantum_info);
 163   if (image_info->number_scenes != 0)
 164     while (image->scene < image_info->scene)
 165     {
 166       /*
 167         Skip to next image.
 168       */
 169       image->scene++;
 170       length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 171       for (y=0; y < (ssize_t) image->rows; y++)
 172       {
 173         count=ReadBlob(image,length,pixels);
 174         if (count != (ssize_t) length)
 175           break;
 176       }
 177     }
 178   scene=0;
 179   count=0;
 180   length=0;
 181   do
 182   {
 183     /*
 184       Read pixels to virtual canvas image then push to image.
 185     */
 186     if ((image_info->ping != MagickFalse) && (image_info->number_scenes != 0))
 187       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 188         break;
 189     if (scene == 0)
 190       {
 191         length=GetQuantumExtent(canvas_image,quantum_info,quantum_type);
 192         count=ReadBlob(image,length,pixels);
 193       }
 194     for (y=0; y < (ssize_t) image->extract_info.height; y++)
 195     {
 196       register const Quantum
 197         *restrict p;
 198
 199       register ssize_t
 200         x;
 201
 202       register Quantum
 203         *restrict q;
 204
 205       if (count != (ssize_t) length)
 206         {
 207           ThrowFileException(exception,CorruptImageError,
 208             "UnexpectedEndOfFile",image->filename);
 209           break;
 210         }
 211       q=GetAuthenticPixels(canvas_image,0,0,canvas_image->columns,1,exception);
 212       if (q == (Quantum *) NULL)
 213         break;
 214       length=ImportQuantumPixels(canvas_image,(CacheView *) NULL,quantum_info,
 215         quantum_type,pixels,exception);
 216       if (SyncAuthenticPixels(canvas_image,exception) == MagickFalse)
 217         break;
 218       if (((y-image->extract_info.y) >= 0) &&
 219           ((y-image->extract_info.y) < (ssize_t) image->rows))
 220         {
 221           p=GetVirtualPixels(canvas_image,canvas_image->extract_info.x,0,
 222             image->columns,1,exception);
 223           q=QueueAuthenticPixels(image,0,y-image->extract_info.y,image->columns,
 224             1,exception);
 225           if ((p == (const Quantum *) NULL) ||
 226               (q == (Quantum *) NULL))
 227             break;
 228           for (x=0; x < (ssize_t) image->columns; x++)
 229           {
 230             SetPixelGray(image,GetPixelGray(canvas_image,p),q);
 231             p+=GetPixelChannels(canvas_image);
 232             q+=GetPixelChannels(image);
 233           }
 234           if (SyncAuthenticPixels(image,exception) == MagickFalse)
 235             break;
 236         }
 237       if (image->previous == (Image *) NULL)
 238         {
 239           status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
 240             image->rows);
 241           if (status == MagickFalse)
 242             break;
 243         }
 244       count=ReadBlob(image,length,pixels);
 245     }
 246     SetQuantumImageType(image,quantum_type);
 247     /*
 248       Proceed to next image.
 249     */
 250     if (image_info->number_scenes != 0)
 251       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
 252         break;
 253     if (count == (ssize_t) length)
 254       {
 255         /*
 256           Allocate next image structure.
 257         */
 258         AcquireNextImage(image_info,image,exception);
 259         if (GetNextImageInList(image) == (Image *) NULL)
 260           {
 261             image=DestroyImageList(image);
 262             return((Image *) NULL);
 263           }
 264         image=SyncNextImageInList(image);
 265         status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
 266           GetBlobSize(image));
 267         if (status == MagickFalse)
 268           break;
 269       }
 270     scene++;
 271   } while (count == (ssize_t) length);
 272   quantum_info=DestroyQuantumInfo(quantum_info);
 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,ExceptionInfo *exception)
 359 %
 360 %  A description of each parameter follows.
 361 %
 362 %    o image_info: the image info.
 363 %
 364 %    o image:  The image.
 365 %
 366 %    o exception: return any errors or warnings in this structure.
 367 %
 368 */
 369 static MagickBooleanType WriteGRAYImage(const ImageInfo *image_info,
 370   Image *image,ExceptionInfo *exception)
 371 {
 372   MagickBooleanType
 373     status;
 374
 375   MagickOffsetType
 376     scene;
 377
 378   QuantumInfo
 379     *quantum_info;
 380
 381   QuantumType
 382     quantum_type;
 383
 384   size_t
 385     length;
 386
 387   ssize_t
 388     count,
 389     y;
 390
 391   unsigned char
 392     *pixels;
 393
 394   /*
 395     Open output image file.
 396   */
 397   assert(image_info != (const ImageInfo *) NULL);
 398   assert(image_info->signature == MagickSignature);
 399   assert(image != (Image *) NULL);
 400   assert(image->signature == MagickSignature);
 401   if (image->debug != MagickFalse)
 402     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 403   assert(exception != (ExceptionInfo *) NULL);
 404   assert(exception->signature == MagickSignature);
 405   status=OpenBlob(image_info,image,WriteBinaryBlobMode,exception);
 406   if (status == MagickFalse)
 407     return(status);
 408   scene=0;
 409   do
 410   {
 411     /*
 412       Write grayscale pixels.
 413     */
 414     if (IsRGBColorspace(image->colorspace) == MagickFalse)
 415       (void) TransformImageColorspace(image,sRGBColorspace,exception);
 416     quantum_type=GrayQuantum;
 417     quantum_info=AcquireQuantumInfo(image_info,image);
 418     if (quantum_info == (QuantumInfo *) NULL)
 419       ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
 420     pixels=GetQuantumPixels(quantum_info);
 421     for (y=0; y < (ssize_t) image->rows; y++)
 422     {
 423       register const Quantum
 424         *restrict p;
 425
 426       p=GetVirtualPixels(image,0,y,image->columns,1,exception);
 427       if (p == (const Quantum *) NULL)
 428         break;
 429       length=ExportQuantumPixels(image,(CacheView *) NULL,quantum_info,
 430         quantum_type,pixels,exception);
 431       count=WriteBlob(image,length,pixels);
 432       if (count != (ssize_t) length)
 433         break;
 434       if (image->previous == (Image *) NULL)
 435         {
 436           status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
 437             image->rows);
 438           if (status == MagickFalse)
 439             break;
 440         }
 441     }
 442     quantum_info=DestroyQuantumInfo(quantum_info);
 443     if (GetNextImageInList(image) == (Image *) NULL)
 444       break;
 445     image=SyncNextImageInList(image);
 446     status=SetImageProgress(image,SaveImagesTag,scene++,
 447       GetImageListLength(image));
 448     if (status == MagickFalse)
 449       break;
 450   } while (image_info->adjoin != MagickFalse);
 451   (void) CloseBlob(image);
 452   return(MagickTrue);
 453 }