sgi.c revision 45ef08fd6a09813e4a8f5ddadf85ba9e0ec2cdc7
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 1999-2013 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
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/color.h"
48#include "MagickCore/color-private.h"
49#include "MagickCore/colormap.h"
50#include "MagickCore/colorspace.h"
51#include "MagickCore/colorspace-private.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/monitor.h"
60#include "MagickCore/monitor-private.h"
61#include "MagickCore/pixel-accessor.h"
62#include "MagickCore/property.h"
63#include "MagickCore/quantum-private.h"
64#include "MagickCore/static.h"
65#include "MagickCore/string_.h"
66#include "MagickCore/module.h"
67
68/*
69  Typedef declaractions.
70*/
71typedef struct _SGIInfo
72{
73  unsigned short
74    magic;
75
76  unsigned char
77    storage,
78    bytes_per_pixel;
79
80  unsigned short
81    dimension,
82    columns,
83    rows,
84    depth;
85
86  size_t
87    minimum_value,
88    maximum_value,
89    sans;
90
91  char
92    name[80];
93
94  size_t
95    pixel_format;
96
97  unsigned char
98    filler[404];
99} SGIInfo;
100
101/*
102  Forward declarations.
103*/
104static MagickBooleanType
105  WriteSGIImage(const ImageInfo *,Image *,ExceptionInfo *);
106/*
107%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
108%                                                                             %
109%                                                                             %
110%                                                                             %
111%   I s S G I                                                                 %
112%                                                                             %
113%                                                                             %
114%                                                                             %
115%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
116%
117%  IsSGI() returns MagickTrue if the image format type, identified by the
118%  magick string, is SGI.
119%
120%  The format of the IsSGI method is:
121%
122%      MagickBooleanType IsSGI(const unsigned char *magick,const size_t length)
123%
124%  A description of each parameter follows:
125%
126%    o magick: compare image format pattern against these bytes.
127%
128%    o length: Specifies the length of the magick string.
129%
130*/
131static MagickBooleanType IsSGI(const unsigned char *magick,const size_t length)
132{
133  if (length < 2)
134    return(MagickFalse);
135  if (memcmp(magick,"\001\332",2) == 0)
136    return(MagickTrue);
137  return(MagickFalse);
138}
139
140/*
141%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
142%                                                                             %
143%                                                                             %
144%                                                                             %
145%   R e a d S G I I m a g e                                                   %
146%                                                                             %
147%                                                                             %
148%                                                                             %
149%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
150%
151%  ReadSGIImage() reads a SGI RGB image file and returns it.  It
152%  allocates the memory necessary for the new Image structure and returns a
153%  pointer to the new image.
154%
155%  The format of the ReadSGIImage method is:
156%
157%      Image *ReadSGIImage(const ImageInfo *image_info,ExceptionInfo *exception)
158%
159%  A description of each parameter follows:
160%
161%    o image_info: the image info.
162%
163%    o exception: return any errors or warnings in this structure.
164%
165*/
166
167static inline size_t MagickMin(const size_t x,const size_t y)
168{
169  if (x < y)
170    return(x);
171  return(y);
172}
173
174static MagickBooleanType SGIDecode(const size_t bytes_per_pixel,
175  ssize_t number_packets,unsigned char *packets,ssize_t number_pixels,
176  unsigned char *pixels)
177{
178  register unsigned char
179    *p,
180    *q;
181
182  size_t
183    pixel;
184
185  ssize_t
186    count;
187
188  p=packets;
189  q=pixels;
190  if (bytes_per_pixel == 2)
191    {
192      for ( ; number_pixels > 0; )
193      {
194        if (number_packets-- == 0)
195          return(MagickFalse);
196        pixel=(size_t) (*p++) << 8;
197        pixel|=(*p++);
198        count=(ssize_t) (pixel & 0x7f);
199        if (count == 0)
200          break;
201        if (count > (ssize_t) number_pixels)
202          return(MagickFalse);
203        number_pixels-=count;
204        if ((pixel & 0x80) != 0)
205          for ( ; count != 0; count--)
206          {
207            if (number_packets-- == 0)
208              return(MagickFalse);
209            *q=(*p++);
210            *(q+1)=(*p++);
211            q+=8;
212          }
213        else
214          {
215            pixel=(size_t) (*p++) << 8;
216            pixel|=(*p++);
217            for ( ; count != 0; count--)
218            {
219              if (number_packets-- == 0)
220                return(MagickFalse);
221              *q=(unsigned char) (pixel >> 8);
222              *(q+1)=(unsigned char) pixel;
223              q+=8;
224            }
225          }
226      }
227      return(MagickTrue);
228    }
229  for ( ; number_pixels > 0; )
230  {
231    if (number_packets-- == 0)
232      return(MagickFalse);
233    pixel=(size_t) (*p++);
234    count=(ssize_t) (pixel & 0x7f);
235    if (count == 0)
236      break;
237    if (count > (ssize_t) number_pixels)
238      return(MagickFalse);
239    number_pixels-=count;
240    if ((pixel & 0x80) != 0)
241      for ( ; count != 0; count--)
242      {
243        if (number_packets-- == 0)
244          return(MagickFalse);
245        *q=(*p++);
246        q+=4;
247      }
248    else
249      {
250        if (number_packets-- == 0)
251          return(MagickFalse);
252        pixel=(size_t) (*p++);
253        for ( ; count != 0; count--)
254        {
255          *q=(unsigned char) pixel;
256          q+=4;
257        }
258      }
259  }
260  return(MagickTrue);
261}
262
263static Image *ReadSGIImage(const ImageInfo *image_info,ExceptionInfo *exception)
264{
265  Image
266    *image;
267
268  MagickBooleanType
269    status;
270
271  MagickSizeType
272    number_pixels;
273
274  register Quantum
275    *q;
276
277  register ssize_t
278    i,
279    x;
280
281  register unsigned char
282    *p;
283
284  SGIInfo
285    iris_info;
286
287  size_t
288    bytes_per_pixel,
289    quantum;
290
291  ssize_t
292    count,
293    y,
294    z;
295
296  unsigned char
297    *iris_pixels;
298
299  /*
300    Open image file.
301  */
302  assert(image_info != (const ImageInfo *) NULL);
303  assert(image_info->signature == MagickSignature);
304  if (image_info->debug != MagickFalse)
305    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
306      image_info->filename);
307  assert(exception != (ExceptionInfo *) NULL);
308  assert(exception->signature == MagickSignature);
309  image=AcquireImage(image_info,exception);
310  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
311  if (status == MagickFalse)
312    {
313      image=DestroyImageList(image);
314      return((Image *) NULL);
315    }
316  /*
317    Read SGI raster header.
318  */
319  iris_info.magic=ReadBlobMSBShort(image);
320  do
321  {
322    /*
323      Verify SGI identifier.
324    */
325    if (iris_info.magic != 0x01DA)
326      ThrowReaderException(CorruptImageError,"ImproperImageHeader");
327    iris_info.storage=(unsigned char) ReadBlobByte(image);
328    switch (iris_info.storage)
329    {
330      case 0x00: image->compression=NoCompression; break;
331      case 0x01: image->compression=RLECompression; break;
332      default:
333        ThrowReaderException(CorruptImageError,"ImproperImageHeader");
334    }
335    iris_info.bytes_per_pixel=(unsigned char) ReadBlobByte(image);
336    if ((iris_info.bytes_per_pixel == 0) || (iris_info.bytes_per_pixel > 2))
337      ThrowReaderException(CorruptImageError,"ImproperImageHeader");
338    iris_info.dimension=ReadBlobMSBShort(image);
339    iris_info.columns=ReadBlobMSBShort(image);
340    iris_info.rows=ReadBlobMSBShort(image);
341    iris_info.depth=ReadBlobMSBShort(image);
342    if ((iris_info.depth == 0) || (iris_info.depth > 4))
343      ThrowReaderException(CorruptImageError,"ImproperImageHeader");
344    iris_info.minimum_value=ReadBlobMSBLong(image);
345    iris_info.maximum_value=ReadBlobMSBLong(image);
346    iris_info.sans=ReadBlobMSBLong(image);
347    (void) ReadBlob(image,sizeof(iris_info.name),(unsigned char *)
348      iris_info.name);
349    iris_info.name[sizeof(iris_info.name)-1]='\0';
350    if (*iris_info.name != '\0')
351      (void) SetImageProperty(image,"label",iris_info.name,exception);
352    iris_info.pixel_format=ReadBlobMSBLong(image);
353    if (iris_info.pixel_format != 0)
354      ThrowReaderException(CorruptImageError,"ImproperImageHeader");
355    count=ReadBlob(image,sizeof(iris_info.filler),iris_info.filler);
356    (void) count;
357    image->columns=iris_info.columns;
358    image->rows=iris_info.rows;
359    image->depth=(size_t) MagickMin(iris_info.depth,MAGICKCORE_QUANTUM_DEPTH);
360    if (iris_info.pixel_format == 0)
361      image->depth=(size_t) MagickMin((size_t) 8*
362        iris_info.bytes_per_pixel,MAGICKCORE_QUANTUM_DEPTH);
363    if (iris_info.depth < 3)
364      {
365        image->storage_class=PseudoClass;
366        image->colors=iris_info.bytes_per_pixel > 1 ? 65535 : 256;
367      }
368    if ((image_info->ping != MagickFalse)  && (image_info->number_scenes != 0))
369      if (image->scene >= (image_info->scene+image_info->number_scenes-1))
370        break;
371    /*
372      Allocate SGI pixels.
373    */
374    bytes_per_pixel=(size_t) iris_info.bytes_per_pixel;
375    number_pixels=(MagickSizeType) iris_info.columns*iris_info.rows;
376    if ((4*bytes_per_pixel*number_pixels) != ((MagickSizeType) (size_t)
377        (4*bytes_per_pixel*number_pixels)))
378      ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
379    iris_pixels=(unsigned char *) AcquireQuantumMemory(iris_info.columns,
380      iris_info.rows*4*bytes_per_pixel*sizeof(*iris_pixels));
381    if (iris_pixels == (unsigned char *) NULL)
382      ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
383    if ((int) iris_info.storage != 0x01)
384      {
385        unsigned char
386          *scanline;
387
388        /*
389          Read standard image format.
390        */
391        scanline=(unsigned char *) AcquireQuantumMemory(iris_info.columns,
392          bytes_per_pixel*sizeof(*scanline));
393        if (scanline == (unsigned char *) NULL)
394          ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
395        for (z=0; z < (ssize_t) iris_info.depth; z++)
396        {
397          p=iris_pixels+bytes_per_pixel*z;
398          for (y=0; y < (ssize_t) iris_info.rows; y++)
399          {
400            count=ReadBlob(image,bytes_per_pixel*iris_info.columns,scanline);
401            if (EOFBlob(image) != MagickFalse)
402              break;
403            if (bytes_per_pixel == 2)
404              for (x=0; x < (ssize_t) iris_info.columns; x++)
405              {
406                *p=scanline[2*x];
407                *(p+1)=scanline[2*x+1];
408                p+=8;
409              }
410            else
411              for (x=0; x < (ssize_t) iris_info.columns; x++)
412              {
413                *p=scanline[x];
414                p+=4;
415              }
416          }
417        }
418        scanline=(unsigned char *) RelinquishMagickMemory(scanline);
419      }
420    else
421      {
422        size_t
423          *runlength;
424
425        ssize_t
426          offset,
427          *offsets;
428
429        unsigned char
430          *packets;
431
432        unsigned int
433          data_order;
434
435        /*
436          Read runlength-encoded image format.
437        */
438        offsets=(ssize_t *) AcquireQuantumMemory((size_t) iris_info.rows,
439          iris_info.depth*sizeof(*offsets));
440        packets=(unsigned char *) AcquireQuantumMemory((size_t)
441          iris_info.columns+10UL,4UL*sizeof(*packets));
442        runlength=(size_t *) AcquireQuantumMemory(iris_info.rows,
443          iris_info.depth*sizeof(*runlength));
444        if ((offsets == (ssize_t *) NULL) ||
445            (packets == (unsigned char *) NULL) ||
446            (runlength == (size_t *) NULL))
447          ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
448        for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
449          offsets[i]=(int) ReadBlobMSBLong(image);
450        for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
451        {
452          runlength[i]=ReadBlobMSBLong(image);
453          if (runlength[i] > (4*(size_t) iris_info.columns+10))
454            ThrowReaderException(CorruptImageError,"ImproperImageHeader");
455        }
456        /*
457          Check data order.
458        */
459        offset=0;
460        data_order=0;
461        for (y=0; ((y < (ssize_t) iris_info.rows) && (data_order == 0)); y++)
462          for (z=0; ((z < (ssize_t) iris_info.depth) && (data_order == 0)); z++)
463          {
464            if (offsets[y+z*iris_info.rows] < offset)
465              data_order=1;
466            offset=offsets[y+z*iris_info.rows];
467          }
468        offset=(ssize_t) TellBlob(image);
469        if (data_order == 1)
470          {
471            for (z=0; z < (ssize_t) iris_info.depth; z++)
472            {
473              p=iris_pixels;
474              for (y=0; y < (ssize_t) iris_info.rows; y++)
475              {
476                if (offset != offsets[y+z*iris_info.rows])
477                  {
478                    offset=offsets[y+z*iris_info.rows];
479                    offset=(ssize_t) SeekBlob(image,(ssize_t) offset,SEEK_SET);
480                  }
481                count=ReadBlob(image,(size_t) runlength[y+z*iris_info.rows],
482                  packets);
483                if (EOFBlob(image) != MagickFalse)
484                  break;
485                offset+=(ssize_t) runlength[y+z*iris_info.rows];
486                status=SGIDecode(bytes_per_pixel,(ssize_t)
487                  (runlength[y+z*iris_info.rows]/bytes_per_pixel),packets,
488                  1L*iris_info.columns,p+bytes_per_pixel*z);
489                if (status == MagickFalse)
490                  ThrowReaderException(CorruptImageError,"ImproperImageHeader");
491                p+=(iris_info.columns*4*bytes_per_pixel);
492              }
493            }
494          }
495        else
496          {
497            MagickOffsetType
498              position;
499
500            position=TellBlob(image);
501            p=iris_pixels;
502            for (y=0; y < (ssize_t) iris_info.rows; y++)
503            {
504              for (z=0; z < (ssize_t) iris_info.depth; z++)
505              {
506                if (offset != offsets[y+z*iris_info.rows])
507                  {
508                    offset=offsets[y+z*iris_info.rows];
509                    offset=(ssize_t) SeekBlob(image,(ssize_t) offset,SEEK_SET);
510                  }
511                count=ReadBlob(image,(size_t) runlength[y+z*iris_info.rows],
512                  packets);
513                if (EOFBlob(image) != MagickFalse)
514                  break;
515                offset+=(ssize_t) runlength[y+z*iris_info.rows];
516                status=SGIDecode(bytes_per_pixel,(ssize_t)
517                  (runlength[y+z*iris_info.rows]/bytes_per_pixel),packets,
518                  1L*iris_info.columns,p+bytes_per_pixel*z);
519                if (status == MagickFalse)
520                  ThrowReaderException(CorruptImageError,"ImproperImageHeader");
521              }
522              p+=(iris_info.columns*4*bytes_per_pixel);
523            }
524            offset=(ssize_t) SeekBlob(image,position,SEEK_SET);
525          }
526        runlength=(size_t *) RelinquishMagickMemory(runlength);
527        packets=(unsigned char *) RelinquishMagickMemory(packets);
528        offsets=(ssize_t *) RelinquishMagickMemory(offsets);
529      }
530    /*
531      Initialize image structure.
532    */
533    image->alpha_trait=iris_info.depth == 4 ? BlendPixelTrait :
534      UndefinedPixelTrait;
535    image->columns=iris_info.columns;
536    image->rows=iris_info.rows;
537    /*
538      Convert SGI raster image to pixel packets.
539    */
540    if (image->storage_class == DirectClass)
541      {
542        /*
543          Convert SGI image to DirectClass pixel packets.
544        */
545        if (bytes_per_pixel == 2)
546          {
547            for (y=0; y < (ssize_t) image->rows; y++)
548            {
549              p=iris_pixels+(image->rows-y-1)*8*image->columns;
550              q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
551              if (q == (Quantum *) NULL)
552                break;
553              for (x=0; x < (ssize_t) image->columns; x++)
554              {
555                SetPixelRed(image,ScaleShortToQuantum((unsigned short)
556                  ((*(p+0) << 8) | (*(p+1)))),q);
557                SetPixelGreen(image,ScaleShortToQuantum((unsigned short)
558                  ((*(p+2) << 8) | (*(p+3)))),q);
559                SetPixelBlue(image,ScaleShortToQuantum((unsigned short)
560                  ((*(p+4) << 8) | (*(p+5)))),q);
561                SetPixelAlpha(image,OpaqueAlpha,q);
562                if (image->alpha_trait == BlendPixelTrait)
563                  SetPixelAlpha(image,ScaleShortToQuantum((unsigned short)
564                    ((*(p+6) << 8) | (*(p+7)))),q);
565                p+=8;
566                q+=GetPixelChannels(image);
567              }
568              if (SyncAuthenticPixels(image,exception) == MagickFalse)
569                break;
570              if (image->previous == (Image *) NULL)
571                {
572                  status=SetImageProgress(image,LoadImageTag,(MagickOffsetType)
573                    y,image->rows);
574                  if (status == MagickFalse)
575                    break;
576                }
577            }
578          }
579        else
580          for (y=0; y < (ssize_t) image->rows; y++)
581          {
582            p=iris_pixels+(image->rows-y-1)*4*image->columns;
583            q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
584            if (q == (Quantum *) NULL)
585              break;
586            for (x=0; x < (ssize_t) image->columns; x++)
587            {
588              SetPixelRed(image,ScaleCharToQuantum(*p),q);
589              SetPixelGreen(image,ScaleCharToQuantum(*(p+1)),q);
590              SetPixelBlue(image,ScaleCharToQuantum(*(p+2)),q);
591              SetPixelAlpha(image,OpaqueAlpha,q);
592              if (image->alpha_trait == BlendPixelTrait)
593                SetPixelAlpha(image,ScaleCharToQuantum(*(p+3)),q);
594              p+=4;
595              q+=GetPixelChannels(image);
596            }
597            if (SyncAuthenticPixels(image,exception) == MagickFalse)
598              break;
599            if (image->previous == (Image *) NULL)
600              {
601                status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
602                  image->rows);
603                if (status == MagickFalse)
604                  break;
605              }
606          }
607      }
608    else
609      {
610        /*
611          Create grayscale map.
612        */
613        if (AcquireImageColormap(image,image->colors,exception) == MagickFalse)
614          ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
615        /*
616          Convert SGI image to PseudoClass pixel packets.
617        */
618        if (bytes_per_pixel == 2)
619          {
620            for (y=0; y < (ssize_t) image->rows; y++)
621            {
622              p=iris_pixels+(image->rows-y-1)*8*image->columns;
623              q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
624              if (q == (Quantum *) NULL)
625                break;
626              for (x=0; x < (ssize_t) image->columns; x++)
627              {
628                quantum=(*p << 8);
629                quantum|=(*(p+1));
630                SetPixelIndex(image,quantum,q);
631                p+=8;
632                q+=GetPixelChannels(image);
633              }
634              if (SyncAuthenticPixels(image,exception) == MagickFalse)
635                break;
636              if (image->previous == (Image *) NULL)
637                {
638                  status=SetImageProgress(image,LoadImageTag,(MagickOffsetType)
639                    y,image->rows);
640                  if (status == MagickFalse)
641                    break;
642                }
643            }
644          }
645        else
646          for (y=0; y < (ssize_t) image->rows; y++)
647          {
648            p=iris_pixels+(image->rows-y-1)*4*image->columns;
649            q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
650            if (q == (Quantum *) NULL)
651              break;
652            for (x=0; x < (ssize_t) image->columns; x++)
653            {
654              SetPixelIndex(image,*p,q);
655              p+=4;
656              q+=GetPixelChannels(image);
657            }
658            if (SyncAuthenticPixels(image,exception) == MagickFalse)
659              break;
660            if (image->previous == (Image *) NULL)
661              {
662                status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
663                image->rows);
664                if (status == MagickFalse)
665                  break;
666              }
667          }
668        (void) SyncImage(image,exception);
669      }
670    iris_pixels=(unsigned char *) RelinquishMagickMemory(iris_pixels);
671    if (EOFBlob(image) != MagickFalse)
672      {
673        ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
674          image->filename);
675        break;
676      }
677    /*
678      Proceed to next image.
679    */
680    if (image_info->number_scenes != 0)
681      if (image->scene >= (image_info->scene+image_info->number_scenes-1))
682        break;
683    iris_info.magic=ReadBlobMSBShort(image);
684    if (iris_info.magic == 0x01DA)
685      {
686        /*
687          Allocate next image structure.
688        */
689        AcquireNextImage(image_info,image,exception);
690        if (GetNextImageInList(image) == (Image *) NULL)
691          {
692            image=DestroyImageList(image);
693            return((Image *) NULL);
694          }
695        image=SyncNextImageInList(image);
696        status=SetImageProgress(image,LoadImagesTag,TellBlob(image),
697          GetBlobSize(image));
698        if (status == MagickFalse)
699          break;
700      }
701  } while (iris_info.magic == 0x01DA);
702  (void) CloseBlob(image);
703  return(GetFirstImageInList(image));
704}
705
706/*
707%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
708%                                                                             %
709%                                                                             %
710%                                                                             %
711%   R e g i s t e r S G I I m a g e                                           %
712%                                                                             %
713%                                                                             %
714%                                                                             %
715%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
716%
717%  RegisterSGIImage() adds properties for the SGI image format to
718%  the list of supported formats.  The properties include the image format
719%  tag, a method to read and/or write the format, whether the format
720%  supports the saving of more than one frame to the same file or blob,
721%  whether the format supports native in-memory I/O, and a brief
722%  description of the format.
723%
724%  The format of the RegisterSGIImage method is:
725%
726%      size_t RegisterSGIImage(void)
727%
728*/
729ModuleExport size_t RegisterSGIImage(void)
730{
731  MagickInfo
732    *entry;
733
734  entry=SetMagickInfo("SGI");
735  entry->decoder=(DecodeImageHandler *) ReadSGIImage;
736  entry->encoder=(EncodeImageHandler *) WriteSGIImage;
737  entry->magick=(IsImageFormatHandler *) IsSGI;
738  entry->description=ConstantString("Irix RGB image");
739  entry->module=ConstantString("SGI");
740  entry->seekable_stream=MagickTrue;
741  (void) RegisterMagickInfo(entry);
742  return(MagickImageCoderSignature);
743}
744
745/*
746%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
747%                                                                             %
748%                                                                             %
749%                                                                             %
750%   U n r e g i s t e r S G I I m a g e                                       %
751%                                                                             %
752%                                                                             %
753%                                                                             %
754%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
755%
756%  UnregisterSGIImage() removes format registrations made by the
757%  SGI module from the list of supported formats.
758%
759%  The format of the UnregisterSGIImage method is:
760%
761%      UnregisterSGIImage(void)
762%
763*/
764ModuleExport void UnregisterSGIImage(void)
765{
766  (void) UnregisterMagickInfo("SGI");
767}
768
769/*
770%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
771%                                                                             %
772%                                                                             %
773%                                                                             %
774%   W r i t e S G I I m a g e                                                 %
775%                                                                             %
776%                                                                             %
777%                                                                             %
778%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
779%
780%  WriteSGIImage() writes an image in SGI RGB encoded image format.
781%
782%  The format of the WriteSGIImage method is:
783%
784%      MagickBooleanType WriteSGIImage(const ImageInfo *image_info,
785%        Image *image,ExceptionInfo *exception)
786%
787%  A description of each parameter follows.
788%
789%    o image_info: the image info.
790%
791%    o image:  The image.
792%
793%    o exception: return any errors or warnings in this structure.
794%
795*/
796
797static size_t SGIEncode(unsigned char *pixels,size_t length,
798  unsigned char *packets)
799{
800  short
801    runlength;
802
803  register unsigned char
804    *p,
805    *q;
806
807  unsigned char
808    *limit,
809    *mark;
810
811  p=pixels;
812  limit=p+length*4;
813  q=packets;
814  while (p < limit)
815  {
816    mark=p;
817    p+=8;
818    while ((p < limit) && ((*(p-8) != *(p-4)) || (*(p-4) != *p)))
819      p+=4;
820    p-=8;
821    length=(size_t) (p-mark) >> 2;
822    while (length != 0)
823    {
824      runlength=(short) (length > 126 ? 126 : length);
825      length-=runlength;
826      *q++=(unsigned char) (0x80 | runlength);
827      for ( ; runlength > 0; runlength--)
828      {
829        *q++=(*mark);
830        mark+=4;
831      }
832    }
833    mark=p;
834    p+=4;
835    while ((p < limit) && (*p == *mark))
836      p+=4;
837    length=(size_t) (p-mark) >> 2;
838    while (length != 0)
839    {
840      runlength=(short) (length > 126 ? 126 : length);
841      length-=runlength;
842      *q++=(unsigned char) runlength;
843      *q++=(*mark);
844    }
845  }
846  *q++='\0';
847  return((size_t) (q-packets));
848}
849
850static MagickBooleanType WriteSGIImage(const ImageInfo *image_info,Image *image,
851  ExceptionInfo *exception)
852{
853  CompressionType
854    compression;
855
856  const char
857    *value;
858
859  MagickBooleanType
860    status;
861
862  MagickOffsetType
863    scene;
864
865  MagickSizeType
866    number_pixels;
867
868  SGIInfo
869    iris_info;
870
871  register const Quantum
872    *p;
873
874  register ssize_t
875    i,
876    x;
877
878  register unsigned char
879    *q;
880
881  ssize_t
882    y,
883    z;
884
885  unsigned char
886    *iris_pixels,
887    *packets;
888
889  /*
890    Open output image file.
891  */
892  assert(image_info != (const ImageInfo *) NULL);
893  assert(image_info->signature == MagickSignature);
894  assert(image != (Image *) NULL);
895  assert(image->signature == MagickSignature);
896  if (image->debug != MagickFalse)
897    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
898  if ((image->columns > 65535UL) || (image->rows > 65535UL))
899    ThrowWriterException(ImageError,"WidthOrHeightExceedsLimit");
900  assert(exception != (ExceptionInfo *) NULL);
901  assert(exception->signature == MagickSignature);
902  status=OpenBlob(image_info,image,WriteBinaryBlobMode,exception);
903  if (status == MagickFalse)
904    return(status);
905  scene=0;
906  do
907  {
908    /*
909      Initialize SGI raster file header.
910    */
911    if (IssRGBCompatibleColorspace(image->colorspace) == MagickFalse)
912      (void) TransformImageColorspace(image,sRGBColorspace,exception);
913    (void) ResetMagickMemory(&iris_info,0,sizeof(iris_info));
914    iris_info.magic=0x01DA;
915    compression=image->compression;
916    if (image_info->compression != UndefinedCompression)
917      compression=image_info->compression;
918    if (image->depth > 8)
919      compression=NoCompression;
920    if (compression == NoCompression)
921      iris_info.storage=(unsigned char) 0x00;
922    else
923      iris_info.storage=(unsigned char) 0x01;
924    iris_info.bytes_per_pixel=(unsigned char) (image->depth > 8 ? 2 : 1);
925    iris_info.dimension=3;
926    iris_info.columns=(unsigned short) image->columns;
927    iris_info.rows=(unsigned short) image->rows;
928    if (image->alpha_trait == BlendPixelTrait)
929      iris_info.depth=4;
930    else
931      {
932        if ((image_info->type != TrueColorType) &&
933            (IsImageGray(image,exception) != MagickFalse))
934          {
935            iris_info.dimension=2;
936            iris_info.depth=1;
937          }
938        else
939          iris_info.depth=3;
940      }
941    iris_info.minimum_value=0;
942    iris_info.maximum_value=(size_t) (image->depth <= 8 ?
943      1UL*ScaleQuantumToChar(QuantumRange) :
944      1UL*ScaleQuantumToShort(QuantumRange));
945    /*
946      Write SGI header.
947    */
948    (void) WriteBlobMSBShort(image,iris_info.magic);
949    (void) WriteBlobByte(image,iris_info.storage);
950    (void) WriteBlobByte(image,iris_info.bytes_per_pixel);
951    (void) WriteBlobMSBShort(image,iris_info.dimension);
952    (void) WriteBlobMSBShort(image,iris_info.columns);
953    (void) WriteBlobMSBShort(image,iris_info.rows);
954    (void) WriteBlobMSBShort(image,iris_info.depth);
955    (void) WriteBlobMSBLong(image,(unsigned int) iris_info.minimum_value);
956    (void) WriteBlobMSBLong(image,(unsigned int) iris_info.maximum_value);
957    (void) WriteBlobMSBLong(image,(unsigned int) iris_info.sans);
958    value=GetImageProperty(image,"label",exception);
959    if (value != (const char *) NULL)
960      (void) CopyMagickString(iris_info.name,value,sizeof(iris_info.name));
961    (void) WriteBlob(image,sizeof(iris_info.name),(unsigned char *)
962      iris_info.name);
963    (void) WriteBlobMSBLong(image,(unsigned int) iris_info.pixel_format);
964    (void) WriteBlob(image,sizeof(iris_info.filler),iris_info.filler);
965    /*
966      Allocate SGI pixels.
967    */
968    number_pixels=(MagickSizeType) image->columns*image->rows;
969    if ((4*iris_info.bytes_per_pixel*number_pixels) !=
970        ((MagickSizeType) (size_t) (4*iris_info.bytes_per_pixel*number_pixels)))
971      ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
972    iris_pixels=(unsigned char *) AcquireQuantumMemory((size_t) number_pixels,
973      4*iris_info.bytes_per_pixel*sizeof(*iris_pixels));
974    if (iris_pixels == (unsigned char *) NULL)
975      ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
976    /*
977      Convert image pixels to uncompressed SGI pixels.
978    */
979    for (y=0; y < (ssize_t) image->rows; y++)
980    {
981      p=GetVirtualPixels(image,0,y,image->columns,1,exception);
982      if (p == (const Quantum *) NULL)
983        break;
984      if (image->depth <= 8)
985        for (x=0; x < (ssize_t) image->columns; x++)
986        {
987          register unsigned char
988            *q;
989
990          q=(unsigned char *) iris_pixels;
991          q+=((iris_info.rows-1)-y)*(4*iris_info.columns)+4*x;
992          *q++=ScaleQuantumToChar(GetPixelRed(image,p));
993          *q++=ScaleQuantumToChar(GetPixelGreen(image,p));
994          *q++=ScaleQuantumToChar(GetPixelBlue(image,p));
995          *q++=ScaleQuantumToChar(GetPixelAlpha(image,p));
996          p+=GetPixelChannels(image);
997        }
998      else
999        for (x=0; x < (ssize_t) image->columns; x++)
1000        {
1001          register unsigned short
1002            *q;
1003
1004          q=(unsigned short *) iris_pixels;
1005          q+=((iris_info.rows-1)-y)*(4*iris_info.columns)+4*x;
1006          *q++=ScaleQuantumToShort(GetPixelRed(image,p));
1007          *q++=ScaleQuantumToShort(GetPixelGreen(image,p));
1008          *q++=ScaleQuantumToShort(GetPixelBlue(image,p));
1009          *q++=ScaleQuantumToShort(GetPixelAlpha(image,p));
1010          p+=GetPixelChannels(image);
1011        }
1012      if (image->previous == (Image *) NULL)
1013        {
1014          status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
1015            image->rows);
1016          if (status == MagickFalse)
1017            break;
1018        }
1019    }
1020    switch (compression)
1021    {
1022      case NoCompression:
1023      {
1024        /*
1025          Write uncompressed SGI pixels.
1026        */
1027        for (z=0; z < (ssize_t) iris_info.depth; z++)
1028        {
1029          for (y=0; y < (ssize_t) iris_info.rows; y++)
1030          {
1031            if (image->depth <= 8)
1032              for (x=0; x < (ssize_t) iris_info.columns; x++)
1033              {
1034                register unsigned char
1035                  *q;
1036
1037                q=(unsigned char *) iris_pixels;
1038                q+=y*(4*iris_info.columns)+4*x+z;
1039                (void) WriteBlobByte(image,*q);
1040              }
1041            else
1042              for (x=0; x < (ssize_t) iris_info.columns; x++)
1043              {
1044                register unsigned short
1045                  *q;
1046
1047                q=(unsigned short *) iris_pixels;
1048                q+=y*(4*iris_info.columns)+4*x+z;
1049                (void) WriteBlobMSBShort(image,*q);
1050              }
1051          }
1052        }
1053        break;
1054      }
1055      default:
1056      {
1057        size_t
1058          length,
1059          number_packets,
1060          *runlength;
1061
1062        ssize_t
1063          offset,
1064          *offsets;
1065
1066        /*
1067          Convert SGI uncompressed pixels.
1068        */
1069        offsets=(ssize_t *) AcquireQuantumMemory(iris_info.rows*iris_info.depth,
1070          sizeof(*offsets));
1071        packets=(unsigned char *) AcquireQuantumMemory((2*(size_t)
1072          iris_info.columns+10)*image->rows,4*sizeof(*packets));
1073        runlength=(size_t *) AcquireQuantumMemory(iris_info.rows,
1074          iris_info.depth*sizeof(*runlength));
1075        if ((offsets == (ssize_t *) NULL) ||
1076            (packets == (unsigned char *) NULL) ||
1077            (runlength == (size_t *) NULL))
1078          ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
1079        offset=512+4*2*((ssize_t) iris_info.rows*iris_info.depth);
1080        number_packets=0;
1081        q=iris_pixels;
1082        for (y=0; y < (ssize_t) iris_info.rows; y++)
1083        {
1084          for (z=0; z < (ssize_t) iris_info.depth; z++)
1085          {
1086            length=SGIEncode(q+z,(size_t) iris_info.columns,packets+
1087              number_packets);
1088            number_packets+=length;
1089            offsets[y+z*iris_info.rows]=offset;
1090            runlength[y+z*iris_info.rows]=(size_t) length;
1091            offset+=(ssize_t) length;
1092          }
1093          q+=(iris_info.columns*4);
1094        }
1095        /*
1096          Write out line start and length tables and runlength-encoded pixels.
1097        */
1098        for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
1099          (void) WriteBlobMSBLong(image,(unsigned int) offsets[i]);
1100        for (i=0; i < (ssize_t) (iris_info.rows*iris_info.depth); i++)
1101          (void) WriteBlobMSBLong(image,(unsigned int) runlength[i]);
1102        (void) WriteBlob(image,number_packets,packets);
1103        /*
1104          Relinquish resources.
1105        */
1106        runlength=(size_t *) RelinquishMagickMemory(runlength);
1107        packets=(unsigned char *) RelinquishMagickMemory(packets);
1108        offsets=(ssize_t *) RelinquishMagickMemory(offsets);
1109        break;
1110      }
1111    }
1112    iris_pixels=(unsigned char *) RelinquishMagickMemory(iris_pixels);
1113    if (GetNextImageInList(image) == (Image *) NULL)
1114      break;
1115    image=SyncNextImageInList(image);
1116    status=SetImageProgress(image,SaveImagesTag,scene++,
1117      GetImageListLength(image));
1118    if (status == MagickFalse)
1119      break;
1120  } while (image_info->adjoin != MagickFalse);
1121  (void) CloseBlob(image);
1122  return(MagickTrue);
1123}
1124