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1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 %                                                                             %
4 %                                                                             %
5 %                                                                             %
6 %                            SSSSS   GGGG  IIIII                              %
7 %                            SS     G        I                                %
8 %                             SSS   G  GG    I                                %
9 %                               SS  G   G    I                                %
10 %                            SSSSS   GGG   IIIII                              %
11 %                                                                             %
12 %                                                                             %
13 %                      Read/Write Irix RGB Image Format                       %
14 %                                                                             %
15 %                              Software Design                                %
16 %                                John Cristy                                  %
17 %                                 July 1992                                   %
18 %                                                                             %
19 %                                                                             %
20 %  Copyright 1999-2010 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 "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/colormap.h"
49 #include "magick/colorspace.h"
50 #include "magick/exception.h"
51 #include "magick/exception-private.h"
52 #include "magick/image.h"
53 #include "magick/image-private.h"
54 #include "magick/list.h"
55 #include "magick/magick.h"
56 #include "magick/memory_.h"
57 #include "magick/monitor.h"
58 #include "magick/monitor-private.h"
59 #include "magick/property.h"
60 #include "magick/quantum-private.h"
61 #include "magick/static.h"
62 #include "magick/string_.h"
63 #include "magick/module.h"
64 \f
65 /*
66   Typedef declaractions.
67 */
68 typedef struct _SGIInfo
69 {
70   unsigned short
71     magic;
72
73   unsigned char
74     storage,
75     bytes_per_pixel;
76
77   unsigned short
78     dimension,
79     columns,
80     rows,
81     depth;
82
83   size_t
84     minimum_value,
85     maximum_value,
86     sans;
87
88   char
89     name[80];
90
91   size_t
92     pixel_format;
93
94   unsigned char
95     filler[404];
96 } SGIInfo;
97 \f
98 /*
99   Forward declarations.
100 */
101 static MagickBooleanType
102   WriteSGIImage(const ImageInfo *,Image *);
103 /*
104 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
105 %                                                                             %
106 %                                                                             %
107 %                                                                             %
108 %   I s S G I                                                                 %
109 %                                                                             %
110 %                                                                             %
111 %                                                                             %
112 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
113 %
114 %  IsSGI() returns MagickTrue if the image format type, identified by the
115 %  magick string, is SGI.
116 %
117 %  The format of the IsSGI method is:
118 %
119 %      MagickBooleanType IsSGI(const unsigned char *magick,const size_t length)
120 %
121 %  A description of each parameter follows:
122 %
123 %    o magick: compare image format pattern against these bytes.
124 %
125 %    o length: Specifies the length of the magick string.
126 %
127 %
128 */
129 static MagickBooleanType IsSGI(const unsigned char *magick,const size_t length)
130 {
131   if (length < 2)
132     return(MagickFalse);
133   if (memcmp(magick,"\001\332",2) == 0)
134     return(MagickTrue);
135   return(MagickFalse);
136 }
137 \f
138 /*
139 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
140 %                                                                             %
141 %                                                                             %
142 %                                                                             %
143 %   R e a d S G I I m a g e                                                   %
144 %                                                                             %
145 %                                                                             %
146 %                                                                             %
147 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
148 %
149 %  ReadSGIImage() reads a SGI RGB image file and returns it.  It
150 %  allocates the memory necessary for the new Image structure and returns a
151 %  pointer to the new image.
152 %
153 %  The format of the ReadSGIImage method is:
154 %
155 %      Image *ReadSGIImage(const ImageInfo *image_info,ExceptionInfo *exception)
156 %
157 %  A description of each parameter follows:
158 %
159 %    o image_info: the image info.
160 %
161 %    o exception: return any errors or warnings in this structure.
162 %
163 */
164
165 static inline size_t MagickMin(const size_t x,const size_t y)
166 {
167   if (x < y)
168     return(x);
169   return(y);
170 }
171
172 static MagickBooleanType SGIDecode(const size_t bytes_per_pixel,
173   ssize_t number_packets,unsigned char *packets,ssize_t number_pixels,
174   unsigned char *pixels)
175 {
176   register unsigned char
177     *p,
178     *q;
179
180   ssize_t
181     count;
182
183   size_t
184     pixel;
185
186   p=packets;
187   q=pixels;
188   if (bytes_per_pixel == 2)
189     {
190       for ( ; number_pixels > 0; )
191       {
192         if (number_packets-- == 0)
193           return(MagickFalse);
194         pixel=(size_t) (*p++) << 8;
195         pixel|=(*p++);
196         count=(ssize_t) (pixel & 0x7f);
197         if (count == 0)
198           break;
199         if (count > (ssize_t) number_pixels)
200           return(MagickFalse);
201         number_pixels-=count;
202         if ((pixel & 0x80) != 0)
203           for ( ; count != 0; count--)
204           {
205             if (number_packets-- == 0)
206               return(MagickFalse);
207             *q=(*p++);
208             *(q+1)=(*p++);
209             q+=8;
210           }
211         else
212           {
213             pixel=(size_t) (*p++) << 8;
214             pixel|=(*p++);
215             for ( ; count != 0; count--)
216             {
217               if (number_packets-- == 0)
218                 return(MagickFalse);
219               *q=(unsigned char) (pixel >> 8);
220               *(q+1)=(unsigned char) pixel;
221               q+=8;
222             }
223           }
224       }
225       return(MagickTrue);
226     }
227   for ( ; number_pixels > 0; )
228   {
229     if (number_packets-- == 0)
230       return(MagickFalse);
231     pixel=(size_t) (*p++);
232     count=(ssize_t) (pixel & 0x7f);
233     if (count == 0)
234       break;
235     if (count > (ssize_t) number_pixels)
236       return(MagickFalse);
237     number_pixels-=count;
238     if ((pixel & 0x80) != 0)
239       for ( ; count != 0; count--)
240       {
241         if (number_packets-- == 0)
242           return(MagickFalse);
243         *q=(*p++);
244         q+=4;
245       }
246     else
247       {
248         if (number_packets-- == 0)
249           return(MagickFalse);
250         pixel=(size_t) (*p++);
251         for ( ; count != 0; count--)
252         {
253           *q=(unsigned char) pixel;
254           q+=4;
255         }
256       }
257   }
258   return(MagickTrue);
259 }
260
261 static Image *ReadSGIImage(const ImageInfo *image_info,ExceptionInfo *exception)
262 {
263   Image
264     *image;
265
266   ssize_t
267     y,
268     z;
269
270   MagickBooleanType
271     status;
272
273   MagickSizeType
274     number_pixels;
275
276   register IndexPacket
277     *indexes;
278
279   register ssize_t
280     i,
281     x;
282
283   register PixelPacket
284     *q;
285
286   register unsigned char
287     *p;
288
289   ssize_t
290     count;
291
292   SGIInfo
293     iris_info;
294
295   size_t
296     bytes_per_pixel;
297
298   unsigned char
299     *iris_pixels;
300
301   size_t
302     quantum;
303
304   /*
305     Open image file.
306   */
307   assert(image_info != (const ImageInfo *) NULL);
308   assert(image_info->signature == MagickSignature);
309   if (image_info->debug != MagickFalse)
310     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
311       image_info->filename);
312   assert(exception != (ExceptionInfo *) NULL);
313   assert(exception->signature == MagickSignature);
314   image=AcquireImage(image_info);
315   status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
316   if (status == MagickFalse)
317     {
318       image=DestroyImageList(image);
319       return((Image *) NULL);
320     }
321   /*
322     Read SGI raster header.
323   */
324   iris_info.magic=ReadBlobMSBShort(image);
325   do
326   {
327     /*
328       Verify SGI identifier.
329     */
330     if (iris_info.magic != 0x01DA)
331       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
332     iris_info.storage=(unsigned char) ReadBlobByte(image);
333     switch (iris_info.storage)
334     {
335       case 0x00: image->compression=NoCompression; break;
336       case 0x01: image->compression=RLECompression; break;
337       default:
338         ThrowReaderException(CorruptImageError,"ImproperImageHeader");
339     }
340     iris_info.bytes_per_pixel=(unsigned char) ReadBlobByte(image);
341     if ((iris_info.bytes_per_pixel == 0) || (iris_info.bytes_per_pixel > 2))
342       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
343     iris_info.dimension=ReadBlobMSBShort(image);
344     iris_info.columns=ReadBlobMSBShort(image);
345     iris_info.rows=ReadBlobMSBShort(image);
346     iris_info.depth=ReadBlobMSBShort(image);
347     if ((iris_info.depth == 0) || (iris_info.depth > 4))
348       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
349     iris_info.minimum_value=ReadBlobMSBLong(image);
350     iris_info.maximum_value=ReadBlobMSBLong(image);
351     iris_info.sans=ReadBlobMSBLong(image);
352     (void) ReadBlob(image,sizeof(iris_info.name),(unsigned char *)
353       iris_info.name);
354     iris_info.name[sizeof(iris_info.name)-1]='\0';
355     if (*iris_info.name != '\0')
356       (void) SetImageProperty(image,"label",iris_info.name);
357     iris_info.pixel_format=ReadBlobMSBLong(image);
358     if (iris_info.pixel_format != 0)
359       ThrowReaderException(CorruptImageError,"ImproperImageHeader");
360     count=ReadBlob(image,sizeof(iris_info.filler),iris_info.filler);
361     image->columns=iris_info.columns;
362     image->rows=iris_info.rows;
363     image->depth=(size_t) MagickMin(iris_info.depth,MAGICKCORE_QUANTUM_DEPTH);
364     if (iris_info.pixel_format == 0)
365       image->depth=(size_t) MagickMin((size_t) 8*
366         iris_info.bytes_per_pixel,MAGICKCORE_QUANTUM_DEPTH);
367     if (iris_info.depth < 3)
368       {
369         image->storage_class=PseudoClass;
370         image->colors=256;
371       }
372     if ((image_info->ping != MagickFalse)  && (image_info->number_scenes != 0))
373       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
374         break;
375     /*
376       Allocate SGI pixels.
377     */
378     bytes_per_pixel=(size_t) iris_info.bytes_per_pixel;
379     number_pixels=(MagickSizeType) iris_info.columns*iris_info.rows;
380     if ((4*bytes_per_pixel*number_pixels) != ((MagickSizeType) (size_t)
381         (4*bytes_per_pixel*number_pixels)))
382       ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
383     iris_pixels=(unsigned char *) AcquireQuantumMemory(iris_info.columns,
384       iris_info.rows*4*bytes_per_pixel*sizeof(*iris_pixels));
385     if (iris_pixels == (unsigned char *) NULL)
386       ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
387     if ((int) iris_info.storage != 0x01)
388       {
389         unsigned char
390           *scanline;
391
392         /*
393           Read standard image format.
394         */
395         scanline=(unsigned char *) AcquireQuantumMemory(iris_info.columns,
396           bytes_per_pixel*sizeof(*scanline));
397         if (scanline == (unsigned char *) NULL)
398           ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
399         for (z=0; z < (ssize_t) iris_info.depth; z++)
400         {
401           p=iris_pixels+bytes_per_pixel*z;
402           for (y=0; y < (ssize_t) iris_info.rows; y++)
403           {
404             count=ReadBlob(image,bytes_per_pixel*iris_info.columns,scanline);
405             if (EOFBlob(image) != MagickFalse)
406               break;
407             if (bytes_per_pixel == 2)
408               for (x=0; x < (ssize_t) iris_info.columns; x++)
409               {
410                 *p=scanline[2*x];
411                 *(p+1)=scanline[2*x+1];
412                 p+=8;
413               }
414             else
415               for (x=0; x < (ssize_t) iris_info.columns; x++)
416               {
417                 *p=scanline[x];
418                 p+=4;
419               }
420           }
421         }
422         scanline=(unsigned char *) RelinquishMagickMemory(scanline);
423       }
424     else
425       {
426         ssize_t
427           offset,
428           *offsets;
429
430         unsigned char
431           *packets;
432
433         unsigned int
434           data_order;
435
436         size_t
437           *runlength;
438
439         /*
440           Read runlength-encoded image format.
441         */
442         offsets=(ssize_t *) AcquireQuantumMemory((size_t) iris_info.rows,
443           iris_info.depth*sizeof(*offsets));
444         packets=(unsigned char *) AcquireQuantumMemory((size_t)
445           iris_info.columns+10UL,4UL*sizeof(*packets));
446         runlength=(size_t *) AcquireQuantumMemory(iris_info.rows,
447           iris_info.depth*sizeof(*runlength));
448         if ((offsets == (ssize_t *) NULL) ||
449             (packets == (unsigned char *) NULL) ||
450             (runlength == (size_t *) NULL))
451           ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
452         for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
453           offsets[i]=(int) ReadBlobMSBLong(image);
454         for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
455         {
456           runlength[i]=ReadBlobMSBLong(image);
457           if (runlength[i] > (4*(size_t) iris_info.columns+10))
458             ThrowReaderException(CorruptImageError,"ImproperImageHeader");
459         }
460         /*
461           Check data order.
462         */
463         offset=0;
464         data_order=0;
465         for (y=0; ((y < (ssize_t) iris_info.rows) && (data_order == 0)); y++)
466           for (z=0; ((z < (ssize_t) iris_info.depth) && (data_order == 0)); z++)
467           {
468             if (offsets[y+z*iris_info.rows] < offset)
469               data_order=1;
470             offset=offsets[y+z*iris_info.rows];
471           }
472         offset=(ssize_t) TellBlob(image);
473         if (data_order == 1)
474           {
475             for (z=0; z < (ssize_t) iris_info.depth; z++)
476             {
477               p=iris_pixels;
478               for (y=0; y < (ssize_t) iris_info.rows; y++)
479               {
480                 if (offset != offsets[y+z*iris_info.rows])
481                   {
482                     offset=offsets[y+z*iris_info.rows];
483                     offset=(ssize_t) SeekBlob(image,(ssize_t) offset,SEEK_SET);
484                   }
485                 count=ReadBlob(image,(size_t) runlength[y+z*iris_info.rows],
486                   packets);
487                 if (EOFBlob(image) != MagickFalse)
488                   break;
489                 offset+=(ssize_t) runlength[y+z*iris_info.rows];
490                 status=SGIDecode(bytes_per_pixel,(ssize_t)
491                   (runlength[y+z*iris_info.rows]/bytes_per_pixel),packets,
492                   1L*iris_info.columns,p+bytes_per_pixel*z);
493                 if (status == MagickFalse)
494                   ThrowReaderException(CorruptImageError,"ImproperImageHeader");
495                 p+=(iris_info.columns*4*bytes_per_pixel);
496               }
497             }
498           }
499         else
500           {
501             MagickOffsetType
502               position;
503            
504             position=TellBlob(image);
505             p=iris_pixels;
506             for (y=0; y < (ssize_t) iris_info.rows; y++)
507             {
508               for (z=0; z < (ssize_t) iris_info.depth; z++)
509               {
510                 if (offset != offsets[y+z*iris_info.rows])
511                   {
512                     offset=offsets[y+z*iris_info.rows];
513                     offset=(ssize_t) SeekBlob(image,(ssize_t) offset,SEEK_SET);
514                   }
515                 count=ReadBlob(image,(size_t) runlength[y+z*iris_info.rows],
516                   packets);
517                 if (EOFBlob(image) != MagickFalse)
518                   break;
519                 offset+=(ssize_t) runlength[y+z*iris_info.rows];
520                 status=SGIDecode(bytes_per_pixel,(ssize_t)
521                   (runlength[y+z*iris_info.rows]/bytes_per_pixel),packets,
522                   1L*iris_info.columns,p+bytes_per_pixel*z);
523                 if (status == MagickFalse)
524                   ThrowReaderException(CorruptImageError,"ImproperImageHeader");
525               }
526               p+=(iris_info.columns*4*bytes_per_pixel);
527             }
528             offset=(ssize_t) SeekBlob(image,position,SEEK_SET);
529           }
530         runlength=(size_t *) RelinquishMagickMemory(runlength);
531         packets=(unsigned char *) RelinquishMagickMemory(packets);
532         offsets=(ssize_t *) RelinquishMagickMemory(offsets);
533       }
534     /*
535       Initialize image structure.
536     */
537     image->matte=iris_info.depth == 4 ? MagickTrue : MagickFalse;
538     image->columns=iris_info.columns;
539     image->rows=iris_info.rows;
540     /*
541       Convert SGI raster image to pixel packets.
542     */
543     if (image->storage_class == DirectClass)
544       {
545         /*
546           Convert SGI image to DirectClass pixel packets.
547         */
548         if (bytes_per_pixel == 2)
549           {
550             for (y=0; y < (ssize_t) image->rows; y++)
551             {
552               p=iris_pixels+(image->rows-y-1)*8*image->columns;
553               q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
554               if (q == (PixelPacket *) NULL)
555                 break;
556               for (x=0; x < (ssize_t) image->columns; x++)
557               {
558                 q->red=ScaleShortToQuantum((unsigned short)
559                   ((*(p+0) << 8) | (*(p+1))));
560                 q->green=ScaleShortToQuantum((unsigned short)
561                   ((*(p+2) << 8) | (*(p+3))));
562                 q->blue=ScaleShortToQuantum((unsigned short)
563                   ((*(p+4) << 8) | (*(p+5))));
564                 SetOpacityPixelComponent(q,OpaqueOpacity);
565                 if (image->matte != MagickFalse)
566                   q->opacity=(Quantum) (QuantumRange-ScaleShortToQuantum(
567                     (unsigned short) ((*(p+6) << 8) | (*(p+7)))));
568                 p+=8;
569                 q++;
570               }
571               if (SyncAuthenticPixels(image,exception) == MagickFalse)
572                 break;
573               if (image->previous == (Image *) NULL)
574                 {
575                   status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
576                 image->rows);
577                   if (status == MagickFalse)
578                     break;
579                 }
580             }
581           }
582         else
583           for (y=0; y < (ssize_t) image->rows; y++)
584           {
585             p=iris_pixels+(image->rows-y-1)*4*image->columns;
586             q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
587             if (q == (PixelPacket *) NULL)
588               break;
589             for (x=0; x < (ssize_t) image->columns; x++)
590             {
591               q->red=ScaleCharToQuantum(*p);
592               q->green=ScaleCharToQuantum(*(p+1));
593               q->blue=ScaleCharToQuantum(*(p+2));
594               SetOpacityPixelComponent(q,OpaqueOpacity);
595               if (image->matte != MagickFalse)
596                 q->opacity=(Quantum) (QuantumRange-ScaleCharToQuantum(*(p+3)));
597               p+=4;
598               q++;
599             }
600             if (SyncAuthenticPixels(image,exception) == MagickFalse)
601               break;
602             if (image->previous == (Image *) NULL)
603               {
604                 status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
605                 image->rows);
606                 if (status == MagickFalse)
607                   break;
608               }
609           }
610       }
611     else
612       {
613         /*
614           Create grayscale map.
615         */
616         if (AcquireImageColormap(image,image->colors) == MagickFalse)
617           ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
618         /*
619           Convert SGI image to PseudoClass pixel packets.
620         */
621         if (bytes_per_pixel == 2)
622           {
623             for (y=0; y < (ssize_t) image->rows; y++)
624             {
625               p=iris_pixels+(image->rows-y-1)*8*image->columns;
626               q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
627               if (q == (PixelPacket *) NULL)
628                 break;
629               indexes=GetAuthenticIndexQueue(image);
630               for (x=0; x < (ssize_t) image->columns; x++)
631               {
632                 quantum=(*p << 8);
633                 quantum|=(*(p+1));
634                 indexes[x]=(IndexPacket) quantum;
635                 p+=8;
636                 q++;
637               }
638               if (SyncAuthenticPixels(image,exception) == MagickFalse)
639                 break;
640               if (image->previous == (Image *) NULL)
641                 {
642                   status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
643                 image->rows);
644                   if (status == MagickFalse)
645                     break;
646                 }
647             }
648           }
649         else
650           for (y=0; y < (ssize_t) image->rows; y++)
651           {
652             p=iris_pixels+(image->rows-y-1)*4*image->columns;
653             q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
654             if (q == (PixelPacket *) NULL)
655               break;
656             indexes=GetAuthenticIndexQueue(image);
657             for (x=0; x < (ssize_t) image->columns; x++)
658             {
659               indexes[x]=(IndexPacket) (*p);
660               p+=4;
661               q++;
662             }
663             if (SyncAuthenticPixels(image,exception) == MagickFalse)
664               break;
665             if (image->previous == (Image *) NULL)
666               {
667                 status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
668                 image->rows);
669                 if (status == MagickFalse)
670                   break;
671               }
672           }
673         (void) SyncImage(image);
674       }
675     iris_pixels=(unsigned char *) RelinquishMagickMemory(iris_pixels);
676     if (EOFBlob(image) != MagickFalse)
677       {
678         ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
679           image->filename);
680         break;
681       }
682     /*
683       Proceed to next image.
684     */
685     if (image_info->number_scenes != 0)
686       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
687         break;
688     iris_info.magic=ReadBlobMSBShort(image);
689     if (iris_info.magic == 0x01DA)
690       {
691         /*
692           Allocate next image structure.
693         */
694         AcquireNextImage(image_info,image);
695         if (GetNextImageInList(image) == (Image *) NULL)
696           {
697             image=DestroyImageList(image);
698             return((Image *) NULL);
699           }
700         image=SyncNextImageInList(image);
701         status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
702           GetBlobSize(image));
703         if (status == MagickFalse)
704           break;
705       }
706   } while (iris_info.magic == 0x01DA);
707   (void) CloseBlob(image);
708   return(GetFirstImageInList(image));
709 }
710 \f
711 /*
712 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
713 %                                                                             %
714 %                                                                             %
715 %                                                                             %
716 %   R e g i s t e r S G I I m a g e                                           %
717 %                                                                             %
718 %                                                                             %
719 %                                                                             %
720 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
721 %
722 %  RegisterSGIImage() adds properties for the SGI image format to
723 %  the list of supported formats.  The properties include the image format
724 %  tag, a method to read and/or write the format, whether the format
725 %  supports the saving of more than one frame to the same file or blob,
726 %  whether the format supports native in-memory I/O, and a brief
727 %  description of the format.
728 %
729 %  The format of the RegisterSGIImage method is:
730 %
731 %      size_t RegisterSGIImage(void)
732 %
733 */
734 ModuleExport size_t RegisterSGIImage(void)
735 {
736   MagickInfo
737     *entry;
738
739   entry=SetMagickInfo("SGI");
740   entry->decoder=(DecodeImageHandler *) ReadSGIImage;
741   entry->encoder=(EncodeImageHandler *) WriteSGIImage;
742   entry->magick=(IsImageFormatHandler *) IsSGI;
743   entry->description=ConstantString("Irix RGB image");
744   entry->module=ConstantString("SGI");
745   entry->seekable_stream=MagickTrue;
746   (void) RegisterMagickInfo(entry);
747   return(MagickImageCoderSignature);
748 }
749 \f
750 /*
751 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
752 %                                                                             %
753 %                                                                             %
754 %                                                                             %
755 %   U n r e g i s t e r S G I I m a g e                                       %
756 %                                                                             %
757 %                                                                             %
758 %                                                                             %
759 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
760 %
761 %  UnregisterSGIImage() removes format registrations made by the
762 %  SGI module from the list of supported formats.
763 %
764 %  The format of the UnregisterSGIImage method is:
765 %
766 %      UnregisterSGIImage(void)
767 %
768 */
769 ModuleExport void UnregisterSGIImage(void)
770 {
771   (void) UnregisterMagickInfo("SGI");
772 }
773 \f
774 /*
775 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
776 %                                                                             %
777 %                                                                             %
778 %                                                                             %
779 %   W r i t e S G I I m a g e                                                 %
780 %                                                                             %
781 %                                                                             %
782 %                                                                             %
783 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
784 %
785 %  WriteSGIImage() writes an image in SGI RGB encoded image format.
786 %
787 %  The format of the WriteSGIImage method is:
788 %
789 %      MagickBooleanType WriteSGIImage(const ImageInfo *image_info,Image *image)
790 %
791 %  A description of each parameter follows.
792 %
793 %    o image_info: the image info.
794 %
795 %    o image:  The image.
796 %
797 */
798
799 static size_t SGIEncode(unsigned char *pixels,size_t length,
800   unsigned char *packets)
801 {
802   short
803     runlength;
804
805   register unsigned char
806     *p,
807     *q;
808
809   unsigned char
810     *limit,
811     *mark;
812
813   p=pixels;
814   limit=p+length*4;
815   q=packets;
816   while (p < limit)
817   {
818     mark=p;
819     p+=8;
820     while ((p < limit) && ((*(p-8) != *(p-4)) || (*(p-4) != *p)))
821       p+=4;
822     p-=8;
823     length=(size_t) (p-mark) >> 2;
824     while (length != 0)
825     {
826       runlength=(short) (length > 126 ? 126 : length);
827       length-=runlength;
828       *q++=(unsigned char) (0x80 | runlength);
829       for ( ; runlength > 0; runlength--)
830       {
831         *q++=(*mark);
832         mark+=4;
833       }
834     }
835     mark=p;
836     p+=4;
837     while ((p < limit) && (*p == *mark))
838       p+=4;
839     length=(size_t) (p-mark) >> 2;
840     while (length != 0)
841     {
842       runlength=(short) (length > 126 ? 126 : length);
843       length-=runlength;
844       *q++=(unsigned char) runlength;
845       *q++=(*mark);
846     }
847   }
848   *q++='\0';
849   return((size_t) (q-packets));
850 }
851
852 static MagickBooleanType WriteSGIImage(const ImageInfo *image_info,Image *image)
853 {
854   CompressionType
855     compression;
856
857   const char
858     *value;
859
860   ssize_t
861     y,
862     z;
863
864   MagickBooleanType
865     status;
866
867   MagickOffsetType
868     scene;
869
870   MagickSizeType
871     number_pixels;
872
873   SGIInfo
874     iris_info;
875
876   register const PixelPacket
877     *p;
878
879   register ssize_t
880     i,
881     x;
882
883   register unsigned char
884     *q;
885
886   unsigned char
887     *iris_pixels,
888     *packets;
889
890   /*
891     Open output image file.
892   */
893   assert(image_info != (const ImageInfo *) NULL);
894   assert(image_info->signature == MagickSignature);
895   assert(image != (Image *) NULL);
896   assert(image->signature == MagickSignature);
897   if (image->debug != MagickFalse)
898     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
899   if ((image->columns > 65535UL) || (image->rows > 65535UL))
900     ThrowWriterException(ImageError,"WidthOrHeightExceedsLimit");
901   status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
902   if (status == MagickFalse)
903     return(status);
904   scene=0;
905   do
906   {
907     /*
908       Initialize SGI raster file header.
909     */
910     if (image->colorspace != RGBColorspace)
911       (void) TransformImageColorspace(image,RGBColorspace);
912     (void) ResetMagickMemory(&iris_info,0,sizeof(iris_info));
913     iris_info.magic=0x01DA;
914     compression=image->compression;
915     if (image_info->compression != UndefinedCompression)
916       compression=image_info->compression;
917     if (image->depth > 8)
918       compression=NoCompression;
919     if (compression == NoCompression)
920       iris_info.storage=(unsigned char) 0x00;
921     else
922       iris_info.storage=(unsigned char) 0x01;
923     iris_info.bytes_per_pixel=(unsigned char) (image->depth > 8 ? 2 : 1);
924     iris_info.dimension=3;
925     iris_info.columns=(unsigned short) image->columns;
926     iris_info.rows=(unsigned short) image->rows;
927     if (image->matte != MagickFalse)
928       iris_info.depth=4;
929     else
930       {
931         if ((image_info->type != TrueColorType) &&
932             (IsGrayImage(image,&image->exception) != MagickFalse))
933           {
934             iris_info.dimension=2;
935             iris_info.depth=1;
936           }
937         else
938           iris_info.depth=3;
939       }
940     iris_info.minimum_value=0;
941     iris_info.maximum_value=(size_t) (image->depth <= 8 ?
942       1UL*ScaleQuantumToChar((Quantum) QuantumRange) :
943       1UL*ScaleQuantumToShort((Quantum) QuantumRange));
944     /*
945       Write SGI header.
946     */
947     (void) WriteBlobMSBShort(image,iris_info.magic);
948     (void) WriteBlobByte(image,iris_info.storage);
949     (void) WriteBlobByte(image,iris_info.bytes_per_pixel);
950     (void) WriteBlobMSBShort(image,iris_info.dimension);
951     (void) WriteBlobMSBShort(image,iris_info.columns);
952     (void) WriteBlobMSBShort(image,iris_info.rows);
953     (void) WriteBlobMSBShort(image,iris_info.depth);
954     (void) WriteBlobMSBLong(image,(unsigned int) iris_info.minimum_value);
955     (void) WriteBlobMSBLong(image,(unsigned int) iris_info.maximum_value);
956     (void) WriteBlobMSBLong(image,(unsigned int) iris_info.sans);
957     value=GetImageProperty(image,"label");
958     if (value != (const char *) NULL)
959       (void) CopyMagickString(iris_info.name,value,sizeof(iris_info.name));
960     (void) WriteBlob(image,sizeof(iris_info.name),(unsigned char *)
961       iris_info.name);
962     (void) WriteBlobMSBLong(image,(unsigned int) iris_info.pixel_format);
963     (void) WriteBlob(image,sizeof(iris_info.filler),iris_info.filler);
964     /*
965       Allocate SGI pixels.
966     */
967     number_pixels=(MagickSizeType) image->columns*image->rows;
968     if ((4*iris_info.bytes_per_pixel*number_pixels) !=
969         ((MagickSizeType) (size_t) (4*iris_info.bytes_per_pixel*number_pixels)))
970       ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
971     iris_pixels=(unsigned char *) AcquireQuantumMemory((size_t) number_pixels,
972       4*iris_info.bytes_per_pixel*sizeof(*iris_pixels));
973     if (iris_pixels == (unsigned char *) NULL)
974       ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
975     /*
976       Convert image pixels to uncompressed SGI pixels.
977     */
978     for (y=0; y < (ssize_t) image->rows; y++)
979     {
980       p=GetVirtualPixels(image,0,y,image->columns,1,&image->exception);
981       if (p == (const PixelPacket *) NULL)
982         break;
983       if (image->depth <= 8)
984         for (x=0; x < (ssize_t) image->columns; x++)
985         {
986           register unsigned char
987             *q;
988
989           q=(unsigned char *) iris_pixels;
990           q+=((iris_info.rows-1)-y)*(4*iris_info.columns)+4*x;
991           *q++=ScaleQuantumToChar(GetRedPixelComponent(p));
992           *q++=ScaleQuantumToChar(GetGreenPixelComponent(p));
993           *q++=ScaleQuantumToChar(GetBluePixelComponent(p));
994           *q++=ScaleQuantumToChar((Quantum) (GetAlphaPixelComponent(p)));
995           p++;
996         }
997       else
998         for (x=0; x < (ssize_t) image->columns; x++)
999         {
1000           register unsigned short
1001             *q;
1002
1003           q=(unsigned short *) iris_pixels;
1004           q+=((iris_info.rows-1)-y)*(4*iris_info.columns)+4*x;
1005           *q++=ScaleQuantumToShort(GetRedPixelComponent(p));
1006           *q++=ScaleQuantumToShort(GetGreenPixelComponent(p));
1007           *q++=ScaleQuantumToShort(GetBluePixelComponent(p));
1008           *q++=ScaleQuantumToShort((Quantum) (GetAlphaPixelComponent(p)));
1009           p++;
1010         }
1011       if (image->previous == (Image *) NULL)
1012         {
1013           status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
1014                 image->rows);
1015           if (status == MagickFalse)
1016             break;
1017         }
1018     }
1019     switch (compression)
1020     {
1021       case NoCompression:
1022       {
1023         /*
1024           Write uncompressed SGI pixels.
1025         */
1026         for (z=0; z < (ssize_t) iris_info.depth; z++)
1027         {
1028           for (y=0; y < (ssize_t) iris_info.rows; y++)
1029           {
1030             if (image->depth <= 8)
1031               for (x=0; x < (ssize_t) iris_info.columns; x++)
1032               {
1033                 register unsigned char
1034                   *q;
1035
1036                 q=(unsigned char *) iris_pixels;
1037                 q+=y*(4*iris_info.columns)+4*x+z;
1038                 (void) WriteBlobByte(image,*q);
1039               }
1040             else
1041               for (x=0; x < (ssize_t) iris_info.columns; x++)
1042               {
1043                 register unsigned short
1044                   *q;
1045
1046                 q=(unsigned short *) iris_pixels;
1047                 q+=y*(4*iris_info.columns)+4*x+z;
1048                 (void) WriteBlobMSBShort(image,*q);
1049               }
1050           }
1051         }
1052         break;
1053       }
1054       default:
1055       {
1056         ssize_t
1057           offset,
1058           *offsets;
1059
1060         size_t
1061           length,
1062           number_packets;
1063
1064         size_t
1065           *runlength;
1066
1067         /*
1068           Convert SGI uncompressed pixels.
1069         */
1070         offsets=(ssize_t *) AcquireQuantumMemory(iris_info.rows*iris_info.depth,
1071           sizeof(*offsets));
1072         packets=(unsigned char *) AcquireQuantumMemory((2*(size_t)
1073           iris_info.columns+10)*image->rows,4*sizeof(*packets));
1074         runlength=(size_t *) AcquireQuantumMemory(iris_info.rows,
1075           iris_info.depth*sizeof(*runlength));
1076         if ((offsets == (ssize_t *) NULL) ||
1077             (packets == (unsigned char *) NULL) ||
1078             (runlength == (size_t *) NULL))
1079           ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
1080         offset=512+4*2*((ssize_t) iris_info.rows*iris_info.depth);
1081         number_packets=0;
1082         q=iris_pixels;
1083         for (y=0; y < (ssize_t) iris_info.rows; y++)
1084         {
1085           for (z=0; z < (ssize_t) iris_info.depth; z++)
1086           {
1087             length=SGIEncode(q+z,(size_t) iris_info.columns,packets+
1088               number_packets);
1089             number_packets+=length;
1090             offsets[y+z*iris_info.rows]=offset;
1091             runlength[y+z*iris_info.rows]=(size_t) length;
1092             offset+=(ssize_t) length;
1093           }
1094           q+=(iris_info.columns*4);
1095         }
1096         /*
1097           Write out line start and length tables and runlength-encoded pixels.
1098         */
1099         for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
1100           (void) WriteBlobMSBLong(image,(unsigned int) offsets[i]);
1101         for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
1102           (void) WriteBlobMSBLong(image,(unsigned int) runlength[i]);
1103         (void) WriteBlob(image,number_packets,packets);
1104         /*
1105           Relinquish resources.
1106         */
1107         runlength=(size_t *) RelinquishMagickMemory(runlength);
1108         packets=(unsigned char *) RelinquishMagickMemory(packets);
1109         offsets=(ssize_t *) RelinquishMagickMemory(offsets);
1110         break;
1111       }
1112     }
1113     iris_pixels=(unsigned char *) RelinquishMagickMemory(iris_pixels);
1114     if (GetNextImageInList(image) == (Image *) NULL)
1115       break;
1116     image=SyncNextImageInList(image);
1117     status=SetImageProgress(image,SaveImagesTag,scene++,
1118       GetImageListLength(image));
1119     if (status == MagickFalse)
1120       break;
1121   } while (image_info->adjoin != MagickFalse);
1122   (void) CloseBlob(image);
1123   return(MagickTrue);
1124 }