null.c revision 3ed852eea50f9d4cd633efb8c2b054b8e33c2530
1/*
2%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3%                                                                             %
4%                                                                             %
5%                                                                             %
6%                        N   N  U   U  L      L                               %
7%                        NN  N  U   U  L      L                               %
8%                        N N N  U   U  L      L                               %
9%                        N  NN  U   U  L      L                               %
10%                        N   N   UUU   LLLLL  LLLLL                           %
11%                                                                             %
12%                                                                             %
13%                    Read/Write Image Of Uniform Color.                       %
14%                                                                             %
15%                              Software Design                                %
16%                                John Cristy                                  %
17%                                 July 1992                                   %
18%                                                                             %
19%                                                                             %
20%  Copyright 1999-2009 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
39/*
40  Include declarations.
41*/
42#include "magick/studio.h"
43#include "magick/blob.h"
44#include "magick/blob-private.h"
45#include "magick/cache.h"
46#include "magick/color.h"
47#include "magick/color-private.h"
48#include "magick/colorspace-private.h"
49#include "magick/exception.h"
50#include "magick/exception-private.h"
51#include "magick/image.h"
52#include "magick/image-private.h"
53#include "magick/list.h"
54#include "magick/magick.h"
55#include "magick/memory_.h"
56#include "magick/pixel-private.h"
57#include "magick/quantum-private.h"
58#include "magick/static.h"
59#include "magick/string_.h"
60#include "magick/module.h"
61
62/*
63  Forward declarations.
64*/
65static MagickBooleanType
66  WriteNULLImage(const ImageInfo *,Image *);
67
68/*
69%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
70%                                                                             %
71%                                                                             %
72%                                                                             %
73%   R e a d N U L L I m a g e                                                 %
74%                                                                             %
75%                                                                             %
76%                                                                             %
77%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
78%
79%  ReadNULLImage creates a constant image and initializes it to the
80%  X server color as specified by the filename.  It allocates the memory
81%  necessary for the new Image structure and returns a pointer to the new
82%  image.
83%
84%  The format of the ReadNULLImage method is:
85%
86%      Image *ReadNULLImage(const ImageInfo *image_info,
87%        ExceptionInfo *exception)
88%
89%  A description of each parameter follows:
90%
91%    o image_info: the image info.
92%
93%    o exception: return any errors or warnings in this structure.
94%
95*/
96static Image *ReadNULLImage(const ImageInfo *image_info,
97  ExceptionInfo *exception)
98{
99  Image
100    *image;
101
102  long
103    y;
104
105  MagickPixelPacket
106    background;
107
108  register IndexPacket
109    *indexes;
110
111  register long
112    x;
113
114  register PixelPacket
115    *q;
116
117  /*
118    Initialize Image structure.
119  */
120  assert(image_info != (const ImageInfo *) NULL);
121  assert(image_info->signature == MagickSignature);
122  if (image_info->debug != MagickFalse)
123    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
124      image_info->filename);
125  assert(exception != (ExceptionInfo *) NULL);
126  assert(exception->signature == MagickSignature);
127  image=AcquireImage(image_info);
128  if (image->columns == 0)
129    image->columns=1;
130  if (image->rows == 0)
131    image->rows=1;
132  image->matte=MagickTrue;
133  GetMagickPixelPacket(image,&background);
134  background.opacity=(MagickRealType) TransparentOpacity;
135  if (image->colorspace == CMYKColorspace)
136    ConvertRGBToCMYK(&background);
137  for (y=0; y < (long) image->rows; y++)
138  {
139    q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
140    if (q == (PixelPacket *) NULL)
141      break;
142    indexes=GetAuthenticIndexQueue(image);
143    for (x=0; x < (long) image->columns; x++)
144    {
145      SetPixelPacket(image,&background,q,indexes);
146      q++;
147      indexes++;
148    }
149    if (SyncAuthenticPixels(image,exception) == MagickFalse)
150      break;
151  }
152  return(GetFirstImageInList(image));
153}
154
155/*
156%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
157%                                                                             %
158%                                                                             %
159%                                                                             %
160%   R e g i s t e r N U L L I m a g e                                         %
161%                                                                             %
162%                                                                             %
163%                                                                             %
164%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
165%
166%  RegisterNULLImage() adds attributes for the NULL image format to
167%  the list of supported formats.  The attributes include the image format
168%  tag, a method to read and/or write the format, whether the format
169%  supports the saving of more than one frame to the same file or blob,
170%  whether the format supports native in-memory I/O, and a brief
171%  description of the format.
172%
173%  The format of the RegisterNULLImage method is:
174%
175%      unsigned long RegisterNULLImage(void)
176%
177*/
178ModuleExport unsigned long RegisterNULLImage(void)
179{
180  MagickInfo
181    *entry;
182
183  entry=SetMagickInfo("NULL");
184  entry->decoder=(DecodeImageHandler *) ReadNULLImage;
185  entry->encoder=(EncodeImageHandler *) WriteNULLImage;
186  entry->adjoin=MagickFalse;
187  entry->format_type=ExplicitFormatType;
188  entry->description=ConstantString("Constant image of uniform color");
189  entry->module=ConstantString("NULL");
190  (void) RegisterMagickInfo(entry);
191  return(MagickImageCoderSignature);
192}
193
194/*
195%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
196%                                                                             %
197%                                                                             %
198%                                                                             %
199%   U n r e g i s t e r N U L L I m a g e                                     %
200%                                                                             %
201%                                                                             %
202%                                                                             %
203%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
204%
205%  UnregisterNULLImage() removes format registrations made by the
206%  NULL module from the list of supported formats.
207%
208%  The format of the UnregisterNULLImage method is:
209%
210%      UnregisterNULLImage(void)
211%
212*/
213ModuleExport void UnregisterNULLImage(void)
214{
215  (void) UnregisterMagickInfo("NULL");
216}
217
218/*
219%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
220%                                                                             %
221%                                                                             %
222%                                                                             %
223%   W r i t e N U L L I m a g e                                               %
224%                                                                             %
225%                                                                             %
226%                                                                             %
227%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
228%
229%  WriteNULLImage writes no output at all. It is useful when specified
230%  as an output format when profiling.
231%
232%  The format of the WriteNULLImage method is:
233%
234%      MagickBooleanType WriteNULLImage(const ImageInfo *image_info,
235%        Image *image)
236%
237%  A description of each parameter follows.
238%
239%    o image_info: the image info.
240%
241%    o image:  The image.
242%
243*/
244static MagickBooleanType WriteNULLImage(const ImageInfo *image_info,
245  Image *image)
246{
247  assert(image_info != (const ImageInfo *) NULL);
248  assert(image_info->signature == MagickSignature);
249  assert(image != (Image *) NULL);
250  assert(image->signature == MagickSignature);
251  if (image->debug != MagickFalse)
252    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
253  return(MagickTrue);
254}
255