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

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %            GGGG  RRRR    AAA   DDDD   IIIII  EEEEE  N   N  TTTTT            %
   7 %           G      R   R  A   A  D   D    I    E      NN  N    T              %
   8 %           G  GG  RRRR   AAAAA  D   D    I    EEE    N N N    T              %
   9 %           G   G  R R    A   A  D   D    I    E      N  NN    T              %
  10 %            GGG   R  R   A   A  DDDD   IIIII  EEEEE  N   N    T              %
  11 %                                                                             %
  12 %                                                                             %
  13 %                   Read An Image Filled Using Gradient.                      %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                                   Cristy                                    %
  17 %                                 July 1992                                   %
  18 %                                                                             %
  19 %                                                                             %
  20 %  Copyright 1999-2018 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 %    https://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/channel.h"
  47 #include "MagickCore/color.h"
  48 #include "MagickCore/color-private.h"
  49 #include "MagickCore/colorspace-private.h"
  50 #include "MagickCore/constitute.h"
  51 #include "MagickCore/draw.h"
  52 #include "MagickCore/exception.h"
  53 #include "MagickCore/exception-private.h"
  54 #include "MagickCore/image.h"
  55 #include "MagickCore/image-private.h"
  56 #include "MagickCore/list.h"
  57 #include "MagickCore/magick.h"
  58 #include "MagickCore/memory_.h"
  59 #include "MagickCore/paint.h"
  60 #include "MagickCore/pixel-accessor.h"
  61 #include "MagickCore/quantum-private.h"
  62 #include "MagickCore/static.h"
  63 #include "MagickCore/string_.h"
  64 #include "MagickCore/module.h"
  65 #include "MagickCore/studio.h"
  66 \f
  67 /*
  68 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  69 %                                                                             %
  70 %                                                                             %
  71 %                                                                             %
  72 %   R e a d G R A D I E N T I m a g e                                         %
  73 %                                                                             %
  74 %                                                                             %
  75 %                                                                             %
  76 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  77 %
  78 %  ReadGRADIENTImage creates a gradient image and initializes it to
  79 %  the color range as specified by the filename.  It allocates the memory
  80 %  necessary for the new Image structure and returns a pointer to the new
  81 %  image.
  82 %
  83 %  The format of the ReadGRADIENTImage method is:
  84 %
  85 %      Image *ReadGRADIENTImage(const ImageInfo *image_info,
  86 %        ExceptionInfo *exception)
  87 %
  88 %  A description of each parameter follows:
  89 %
  90 %    o image_info: the image info.
  91 %
  92 %    o exception: return any errors or warnings in this structure.
  93 %
  94 */
  95 static Image *ReadGRADIENTImage(const ImageInfo *image_info,
  96   ExceptionInfo *exception)
  97 {
  98   char
  99     colorname[MagickPathExtent+4];
 100
 101   Image
 102     *image;
 103
 104   ImageInfo
 105     *read_info;
 106
 107   MagickBooleanType
 108     icc_color,
 109     status;
 110
 111   StopInfo
 112     *stops;
 113
 114   /*
 115     Initialize Image structure.
 116   */
 117   assert(image_info != (const ImageInfo *) NULL);
 118   assert(image_info->signature == MagickCoreSignature);
 119   if (image_info->debug != MagickFalse)
 120     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
 121       image_info->filename);
 122   assert(exception != (ExceptionInfo *) NULL);
 123   assert(exception->signature == MagickCoreSignature);
 124   read_info=CloneImageInfo(image_info);
 125   SetImageInfoBlob(read_info,(void *) NULL,0);
 126   (void) CopyMagickString(colorname,image_info->filename,MagickPathExtent);
 127   (void) sscanf(image_info->filename,"%[^-]",colorname);
 128   (void) FormatLocaleString(read_info->filename,MagickPathExtent,"xc:%s",
 129     colorname);
 130   image=ReadImage(read_info,exception);
 131   read_info=DestroyImageInfo(read_info);
 132   if (image == (Image *) NULL)
 133     return((Image *) NULL);
 134   (void) SetImageAlpha(image,(Quantum) TransparentAlpha,exception);
 135   (void) CopyMagickString(image->filename,image_info->filename,
 136     MagickPathExtent);
 137   icc_color=MagickFalse;
 138   if (LocaleCompare(colorname,"icc") == 0)
 139     {
 140       (void) ConcatenateMagickString(colorname,"-",MagickPathExtent);
 141       (void) sscanf(image_info->filename,"%*[^-]-%[^-]",colorname+4);
 142       icc_color=MagickTrue;
 143     }
 144   stops=(StopInfo *) AcquireQuantumMemory(2,sizeof(*stops));
 145   if (stops == (StopInfo *) NULL)
 146     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
 147   stops[0].offset=0.0;
 148   stops[1].offset=1.0;
 149   status=QueryColorCompliance(colorname,AllCompliance,&stops[0].color,
 150     exception);
 151   if (status == MagickFalse)
 152     {
 153       stops=(StopInfo *) RelinquishMagickMemory(stops);
 154       image=DestroyImage(image);
 155       return((Image *) NULL);
 156     }
 157   (void) SetImageColorspace(image,stops[0].color.colorspace,exception);
 158   (void) CopyMagickString(colorname,"white",MagickPathExtent);
 159   if (GetPixelInfoIntensity(image,&stops[0].color) > (QuantumRange/2.0))
 160     (void) CopyMagickString(colorname,"black",MagickPathExtent);
 161   if (icc_color == MagickFalse)
 162     (void) sscanf(image_info->filename,"%*[^-]-%[^-]",colorname);
 163   else
 164     (void) sscanf(image_info->filename,"%*[^-]-%*[^-]-%[^-]",colorname);
 165   status=QueryColorCompliance(colorname,AllCompliance,&stops[1].color,
 166     exception);
 167   if (status == MagickFalse)
 168     {
 169       stops=(StopInfo *) RelinquishMagickMemory(stops);
 170       image=DestroyImage(image);
 171       return((Image *) NULL);
 172     }
 173   image->alpha_trait=stops[0].color.alpha_trait;
 174   if (stops[1].color.alpha_trait != UndefinedPixelTrait)
 175     image->alpha_trait=stops[1].color.alpha_trait;
 176   status=GradientImage(image,LocaleCompare(image_info->magick,"GRADIENT") == 0 ?
 177     LinearGradient : RadialGradient,PadSpread,stops,2,exception);
 178   stops=(StopInfo *) RelinquishMagickMemory(stops);
 179   if (status == MagickFalse)
 180     {
 181       image=DestroyImageList(image);
 182       return((Image *) NULL);
 183     }
 184   return(GetFirstImageInList(image));
 185 }
 186 \f
 187 /*
 188 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 189 %                                                                             %
 190 %                                                                             %
 191 %                                                                             %
 192 %   R e g i s t e r G R A D I E N T I m a g e                                 %
 193 %                                                                             %
 194 %                                                                             %
 195 %                                                                             %
 196 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 197 %
 198 %  RegisterGRADIENTImage() adds attributes for the GRADIENT image format
 199 %  to the list of supported formats.  The attributes include the image format
 200 %  tag, a method to read and/or write the format, whether the format
 201 %  supports the saving of more than one frame to the same file or blob,
 202 %  whether the format supports native in-memory I/O, and a brief
 203 %  description of the format.
 204 %
 205 %  The format of the RegisterGRADIENTImage method is:
 206 %
 207 %      size_t RegisterGRADIENTImage(void)
 208 %
 209 */
 210 ModuleExport size_t RegisterGRADIENTImage(void)
 211 {
 212   MagickInfo
 213     *entry;
 214
 215   entry=AcquireMagickInfo("GRADIENT","GRADIENT",
 216     "Gradual linear passing from one shade to another");
 217   entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
 218   entry->flags^=CoderAdjoinFlag;
 219   entry->flags|=CoderRawSupportFlag;
 220   entry->format_type=ImplicitFormatType;
 221   (void) RegisterMagickInfo(entry);
 222   entry=AcquireMagickInfo("GRADIENT","RADIAL-GRADIENT",
 223     "Gradual radial passing from one shade to another");
 224   entry->decoder=(DecodeImageHandler *) ReadGRADIENTImage;
 225   entry->flags^=CoderAdjoinFlag;
 226   entry->flags|=CoderRawSupportFlag;
 227   entry->format_type=ImplicitFormatType;
 228   (void) RegisterMagickInfo(entry);
 229   return(MagickImageCoderSignature);
 230 }
 231 \f
 232 /*
 233 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 234 %                                                                             %
 235 %                                                                             %
 236 %                                                                             %
 237 %   U n r e g i s t e r G R A D I E N T I m a g e                             %
 238 %                                                                             %
 239 %                                                                             %
 240 %                                                                             %
 241 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 242 %
 243 %  UnregisterGRADIENTImage() removes format registrations made by the
 244 %  GRADIENT module from the list of supported formats.
 245 %
 246 %  The format of the UnregisterGRADIENTImage method is:
 247 %
 248 %      UnregisterGRADIENTImage(void)
 249 %
 250 */
 251 ModuleExport void UnregisterGRADIENTImage(void)
 252 {
 253   (void) UnregisterMagickInfo("RADIAL-GRADIENT");
 254   (void) UnregisterMagickInfo("GRADIENT");
 255 }