]> granicus.if.org Git - imagemagick/blob - coders/djvu.c
00a43c8c4c3d4ea71a09c291771101cbf4dbeec7
[imagemagick] / coders / djvu.c
1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 %                                                                             %
4 %                                                                             %
5 %                                                                             %
6 %                         DDDD       J  V   V  U   U                          %
7 %                         D   D      J  V   V  U   U                          %
8 %                         D   D      J  V   V  U   U                          %
9 %                         D   D  J   J   V V   U   U                          %
10 %                         DDDD    JJJ     V     UUU                           %
11 %                                                                             %
12 %                                                                             %
13 %                             Read DjVu Images.                               %
14 %                                                                             %
15 %                              Software Design                                %
16 %                                John Cristy                                  %
17 %                                 July 1992                                   %
18 %                                                                             %
19 %                                                                             %
20 %  Copyright 1999-2012 ImageMagick Studio LLC, a non-profit organization      %
21 %  dedicated to making software imaging solutions freely available.           %
22 %                                                                             %
23 %  You may not use this file except in compliance with the License.  You may  %
24 %  obtain a copy of the License at                                            %
25 %                                                                             %
26 %    http://www.imagemagick.org/script/license.php                            %
27 %                                                                             %
28 %  Unless required by applicable law or agreed to in writing, software        %
29 %  distributed under the License is distributed on an "AS IS" BASIS,          %
30 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
31 %  See the License for the specific language governing permissions and        %
32 %  limitations under the License.                                             %
33 %                                                                             %
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35 %
36 %
37 */
38 \f
39 /*
40   Include declarations.
41 */
42 #include "MagickCore/studio.h"
43 #include "MagickCore/blob.h"
44 #include "MagickCore/blob-private.h"
45 #include "MagickCore/cache.h"
46 #include "MagickCore/colormap.h"
47 #include "MagickCore/constitute.h"
48 #include "MagickCore/exception.h"
49 #include "MagickCore/exception-private.h"
50 #include "MagickCore/list.h"
51 #include "MagickCore/magick.h"
52 #include "MagickCore/memory_.h"
53 #include "MagickCore/monitor.h"
54 #include "MagickCore/monitor-private.h"
55 #include "MagickCore/pixel-accessor.h"
56 #include "MagickCore/quantum-private.h"
57 #include "MagickCore/static.h"
58 #include "MagickCore/string_.h"
59 #include "MagickCore/module.h"
60 #if defined(MAGICKCORE_DJVU_DELEGATE)
61 #include <libdjvu/ddjvuapi.h>
62 #endif
63 \f
64 /*
65 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
66 %                                                                             %
67 %                                                                             %
68 %                                                                             %
69 %   I s D J V U                                                               %
70 %                                                                             %
71 %                                                                             %
72 %                                                                             %
73 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
74 %
75 %  IsDJVU() returns MagickTrue if the image format type, identified by the
76 %  magick string, is DJVU.
77 %
78 %  The format of the IsDJVU method is:
79 %
80 %      MagickBooleanType IsDJVU(const unsigned char *magick,const size_t length)
81 %
82 %  A description of each parameter follows:
83 %
84 %    o magick: compare image format pattern against these bytes.
85 %
86 %    o length: Specifies the length of the magick string.
87 %
88 */
89 static MagickBooleanType IsDJVU(const unsigned char *magick,const size_t length)
90 {
91   if (length < 8)
92     return(MagickFalse);
93   if (memcmp(magick,"AT&TFORM",8) == 0)
94     return(MagickTrue);
95   return(MagickFalse);
96 }
97 \f
98 #if defined(MAGICKCORE_DJVU_DELEGATE)
99 /*
100 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
101 %                                                                             %
102 %                                                                             %
103 %                                                                             %
104 %   R e a d D J V U I m a g e                                                 %
105 %                                                                             %
106 %                                                                             %
107 %                                                                             %
108 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
109 %
110 %  ReadDJVUImage() reads DJVU image and returns it.  It allocates the memory
111 %  necessary for the new Image structure and returns a pointer to the new
112 %  image or set of images.
113 %
114 %  The format of the ReadDJVUImage method is:
115 %
116 %      Image *ReadDJVUImage(const ImageInfo *image_info,
117 %        ExceptionInfo *exception)
118 %
119 %  A description of each parameter follows:
120 %
121 %    o image_info: the image info.
122 %
123 %    o exception: return any errors or warnings in this structure.
124 %
125 */
126
127 #if defined(__cplusplus) || defined(c_plusplus)
128 extern "C" {
129 #endif
130
131 typedef struct _LoadContext
132    LoadContext;
133
134 struct _LoadContext
135 {
136   ddjvu_context_t* context;
137   ddjvu_document_t *document;
138   ddjvu_page_t *page;
139   int streamid;
140   int pages;
141   Image *image;
142 };
143
144 #define BLOCKSIZE  65536
145 #if 0
146 static void
147 pump_data(Image *image, LoadContext* lc)
148 {
149         int blocksize = BLOCKSIZE;
150         char data[BLOCKSIZE];
151         int size;
152
153         /* i might check for a condition! */
154         while ((size = (size_t) ReadBlob(image,(size_t) blocksize,data)) == blocksize) {
155                 ddjvu_stream_write(lc->document, lc->streamid, data, size);
156         }
157         if (size)
158                 ddjvu_stream_write(lc->document, lc->streamid, data, size);
159         ddjvu_stream_close(lc->document, lc->streamid, 0);
160 }
161 #endif
162
163 /* returns NULL only after all is delivered! */
164 static ddjvu_message_t*
165 pump_data_until_message(LoadContext *lc,Image *image) /* ddjvu_context_t *context, type ddjvu_document_type_t */
166 {
167         size_t blocksize = BLOCKSIZE;
168         unsigned char data[BLOCKSIZE];
169         size_t size;
170         ddjvu_message_t *message;
171
172         /* i might check for a condition! */
173         size=0;
174         while (!(message = ddjvu_message_peek(lc->context))
175                && (size = (size_t) ReadBlob(image,(size_t) blocksize,data)) == blocksize) {
176                 ddjvu_stream_write(lc->document, lc->streamid, (char *) data, size);
177         }
178         if (message)
179                 return message;
180         if (size)
181                 ddjvu_stream_write(lc->document, lc->streamid, (char *) data, size);
182         ddjvu_stream_close(lc->document, lc->streamid, 0);
183         return NULL;
184 }
185 #define DEBUG 0
186
187 #if DEBUG
188 static const char*
189 message_tag_name(ddjvu_message_tag_t tag)
190 {
191    static char* names[] =
192       {
193          "ERROR",
194          "INFO",
195          "NEWSTREAM",
196          "DOCINFO",
197          "PAGEINFO",
198          "RELAYOUT",
199          "REDISPLAY",
200          "CHUNK",
201          "THUMBNAIL",
202          "PROGRESS",
203       };
204    if (tag <= DDJVU_PROGRESS)
205       return names[tag];
206    else {
207       /* bark! */
208       return 0;
209    }
210 }
211 #endif
212
213 /* write out nice info on the message,
214  * and store in *user* data the info on progress.
215  * */
216 int
217 process_message(ddjvu_message_t *message)
218 {
219
220 #if 0
221    ddjvu_context_t* context= message->m_any.context;
222 #endif
223
224    if (! message)
225       return(-1);
226 #if DEBUG
227    printf("*** %s: %s.\n",__FUNCTION__, message_tag_name(message->m_any.tag));
228 #endif
229
230
231    switch (message->m_any.tag){
232    case DDJVU_DOCINFO:
233    {
234       ddjvu_document_t* document= message->m_any.document;
235       /* ddjvu_document_decoding_status  is set by libdjvu! */
236       /* we have some info on the document  */
237       LoadContext *lc = (LoadContext *) ddjvu_document_get_user_data(document);
238       lc->pages = ddjvu_document_get_pagenum(document);
239 #if DEBUG
240       printf("the doc has %d pages\n", ddjvu_document_get_pagenum(document));
241 #endif
242       break;
243    }
244    case DDJVU_CHUNK:
245 #if DEBUG
246            printf("the name of the chunk is: %s\n", message->m_chunk.chunkid);
247 #endif
248            break;
249
250
251    case DDJVU_RELAYOUT:
252    case DDJVU_PAGEINFO:
253    {
254 #if 0
255       ddjvu_page_t* page = message->m_any.page;
256       page_info* info = ddjvu_page_get_user_data(page);
257
258       printf("page decoding status: %d %s%s%s\n",
259              ddjvu_page_decoding_status(page),
260              status_color, status_name(ddjvu_page_decoding_status(page)), color_reset);
261
262       printf("the page LAYOUT changed: width x height: %d x %d @ %d dpi. Version %d, type %d\n",
263              // printf("page info:\n width x height: %d x %d @ %d dpi, version %d, type %d\n",
264              ddjvu_page_get_width(page),
265              ddjvu_page_get_height(page),
266              ddjvu_page_get_resolution(page),
267              ddjvu_page_get_version(page),
268              /* DDJVU_PAGETYPE_BITONAL */
269              ddjvu_page_get_type(page));
270
271       info->info = 1;
272 #endif
273       break;
274    }
275
276    case DDJVU_REDISPLAY:
277    {
278
279 #if 0
280     ddjvu_page_t* page = message->m_any.page;
281       page_info* info = ddjvu_page_get_user_data(page);
282
283       printf("the page can/should be REDISPLAYED\n");
284       info->display = 1;
285 #endif
286       break;
287    }
288
289    case DDJVU_PROGRESS:
290 #if DEBUG
291            printf("PROGRESS:\n");
292 #endif
293            break;
294    case DDJVU_ERROR:
295            printf("simply ERROR!\n message:\t%s\nfunction:\t%s(file %s)\nlineno:\t%d\n",
296                   message->m_error.message,
297                   message->m_error.function,
298                   message->m_error.filename,
299                   message->m_error.lineno);
300            break;
301    case DDJVU_INFO:
302 #if DEBUG
303            printf("INFO: %s!\n", message->m_info.message);
304 #endif
305            break;
306    default:
307       printf("unexpected\n");
308    };
309   return(message->m_any.tag);
310 }
311
312
313 #if defined(__cplusplus) || defined(c_plusplus)
314 }
315 #endif
316
317
318 #define RGB 1
319
320 /*
321  * DjVu advertised readiness to provide bitmap: So get it!
322  * we use the RGB format!
323  */
324 static void
325 get_page_image(LoadContext *lc, ddjvu_page_t *page, int x, int y, int w, int h, const ImageInfo *image_info, ExceptionInfo *exception ) {
326   ddjvu_format_t
327     *format;
328
329   ddjvu_page_type_t
330     type;
331
332   Image
333     *image;
334
335   int
336     ret,
337     stride;
338
339   unsigned char
340     *q;
341
342         ddjvu_rect_t rect;
343         rect.x = x;
344         rect.y = y;
345         rect.w = (unsigned int) w;             /* /10 */
346         rect.h = (unsigned int) h;             /* /10 */
347
348         image = lc->image;
349         type = ddjvu_page_get_type(lc->page);
350
351         /* stride of this temporary buffer: */
352         stride = (type == DDJVU_PAGETYPE_BITONAL)?
353                 (image->columns + 7)/8 : image->columns *3;
354
355         q = (unsigned char *) AcquireQuantumMemory(image->rows,stride);
356         if (q == (unsigned char *) NULL)
357           return;
358
359         format = ddjvu_format_create(
360                 (type == DDJVU_PAGETYPE_BITONAL)?DDJVU_FORMAT_LSBTOMSB : DDJVU_FORMAT_RGB24,
361                 /* DDJVU_FORMAT_RGB24
362                  * DDJVU_FORMAT_RGBMASK32*/
363                 /* DDJVU_FORMAT_RGBMASK32 */
364                 0, NULL);
365
366 #if 0
367         /* fixme:  ThrowReaderException is a macro, which uses  `exception' variable */
368         if (format == NULL)
369                 {
370                         abort();
371                         /* ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed"); */
372                 }
373
374 #endif
375         ddjvu_format_set_row_order(format, 1);
376         ddjvu_format_set_y_direction(format, 1);
377
378         ret = ddjvu_page_render(page,
379                                     DDJVU_RENDER_COLOR, /* ddjvu_render_mode_t */
380                                     &rect,
381                                     &rect,     /* mmc: ?? */
382                                     format,
383                                     stride, /* ?? */
384                                     (char*)q);
385         (void) ret;
386         ddjvu_format_release(format);
387
388
389         if (type == DDJVU_PAGETYPE_BITONAL) {
390                 /*  */
391 #if DEBUG
392                 printf("%s: expanding BITONAL page/image\n", __FUNCTION__);
393 #endif
394                 size_t bit, byte;
395
396                 for (y=0; y < (ssize_t) image->rows; y++)
397                         {
398                                 Quantum * o = QueueAuthenticPixels(image,0,y,image->columns,1,exception);
399                                 if (o == (Quantum *) NULL)
400                                         break;
401                                 bit=0;
402                                 byte=0;
403
404                                 /* fixme:  the non-aligned, last =<7 bits ! that's ok!!!*/
405                                 for (x= 0; x < (ssize_t) image->columns; x++)
406                                         {
407                                                 if (bit == 0) byte= (size_t) q[(y * stride) + (x / 8)];
408
409                                                 SetPixelIndex(image,(Quantum) (((byte & 0x01) != 0) ? 0x00 : 0x01),o);
410                                                 bit++;
411                                                 if (bit == 8)
412                                                         bit=0;
413                                                 byte>>=1;
414                                           o+=GetPixelChannels(image);
415                                         }
416                                 if (SyncAuthenticPixels(image,exception) == MagickFalse)
417                                         break;
418                         }
419                 if (!image->ping)
420                   SyncImage(image,exception);
421         } else {
422 #if DEBUG
423                 printf("%s: expanding PHOTO page/image\n", __FUNCTION__);
424 #endif
425                 /* now transfer line-wise: */
426                 ssize_t i;
427 #if 0
428                 /* old: */
429                 char* r;
430 #else
431                 register Quantum *r;
432                 unsigned char *s;
433 #endif
434                 s=q;
435                 for (i = 0;i< (ssize_t) image->rows; i++)
436                         {
437 #if DEBUG
438                                if (i % 1000 == 0) printf("%d\n",i);
439 #endif
440                                r = QueueAuthenticPixels(image,0,i,image->columns,1,exception);
441                                if (r == (Quantum *) NULL)
442                                  break;
443                   for (x=0; x < (ssize_t) image->columns; x++)
444                   {
445                     SetPixelRed(image,ScaleCharToQuantum(*s++),r);
446                     SetPixelGreen(image,ScaleCharToQuantum(*s++),r);
447                     SetPixelBlue(image,ScaleCharToQuantum(*s++),r);
448                     r+=GetPixelChannels(image);
449                   }
450
451                               SyncAuthenticPixels(image,exception);
452                         }
453         }
454         q=(unsigned char *) RelinquishMagickMemory(q);
455 }
456
457
458 #if defined(MAGICKCORE_DJVU_DELEGATE)
459
460 #if 0
461 static int
462 get_page_line(LoadContext *lc, int row, QuantumInfo* quantum_info)
463 {
464   ddjvu_format_t
465     *format;
466
467   int
468     ret;
469
470   size_t
471     stride;
472
473   unsigned char
474     *q;
475
476         ddjvu_rect_t rect, pagerect;
477         rect.x = 0;
478         rect.y = row;
479         rect.w = lc->image->columns;             /* /10 */
480         rect.h = 1;             /* /10 */
481
482         pagerect.x = 0;
483         pagerect.y = 0;
484         pagerect.w = lc->image->columns;
485         pagerect.h = lc->image->rows;
486
487
488         format = ddjvu_format_create(
489 #if RGB
490                 DDJVU_FORMAT_RGB24
491 #else
492                 DDJVU_FORMAT_GREY8
493 #endif
494                 ,
495                 0, NULL);
496         ddjvu_format_set_row_order(format, 1);
497         ddjvu_format_set_y_direction(format, 1);
498
499         stride=1;
500 #if RGB
501         stride=3;
502 #endif
503         q = (unsigned char *) AcquireQuantumMemory(lc->image->columns,stride);
504
505         ret = ddjvu_page_render(lc->page,
506                                     DDJVU_RENDER_COLOR, /* ddjvu_render_mode_t */
507                                     &pagerect,
508                                     &rect,     /* mmc: ?? */
509                                     format,
510                                     pagerect.w * 3, /* ?? */
511                                     (char*)q);
512
513         ImportQuantumPixels(lc->image,
514                             (CacheView *) NULL,
515                             quantum_info,
516 #if RGB
517                             RGBQuantum
518 #else
519                             GrayQuantum
520 #endif
521                             ,q,&lc->image->exception);
522         q=(unsigned char *) RelinquishMagickMemory(q);
523         ddjvu_format_release(format);
524         return ret;
525 }
526 #endif
527 #endif
528
529 /*
530 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
531 %                                                                             %
532 %                                                                             %
533 %                                                                             %
534 %   R e a d O n e D J V U I m a g e                                           %
535 %                                                                             %
536 %                                                                             %
537 %                                                                             %
538 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
539 %
540 %  ReadOneDJVUImage() reads a Portable Network Graphics (DJVU) image file
541 %  (minus the 8-byte signature)  and returns it.  It allocates the memory
542 %  necessary for the new Image structure and returns a pointer to the new
543 %  image.
544 %
545 %  The format of the ReadOneDJVUImage method is:
546 %
547 %      Image *ReadOneDJVUImage(MngInfo *mng_info, const ImageInfo *image_info,
548 %         ExceptionInfo *exception)
549 %
550 %  A description of each parameter follows:
551 %
552 %    o mng_info: Specifies a pointer to a MngInfo structure.
553 %
554 %    o image_info: the image info.
555 %
556 %    o exception: return any errors or warnings in this structure.
557 %
558 */
559
560 static inline double MagickMax(const double x,const double y)
561 {
562   if (x > y)
563     return(x);
564   return(y);
565 }
566
567 static Image *ReadOneDJVUImage(LoadContext* lc,const int pagenum,
568   const ImageInfo *image_info,ExceptionInfo *exception)
569 {
570   ddjvu_page_type_t
571      type;
572
573   ddjvu_pageinfo_t info;
574   ddjvu_message_t *message;
575   Image *image;
576   int logging;
577   int tag;
578
579         /* so, we know that the page is there! Get its dimension, and  */
580
581         /* Read one DJVU image */
582         image = lc->image;
583
584         /* register Quantum *q; */
585
586         logging=LogMagickEvent(CoderEvent,GetMagickModule(), "  enter ReadOneDJVUImage()");
587         (void) logging;
588
589 #if DEBUG
590         printf("====  Loading the page %d\n", pagenum);
591 #endif
592         lc->page = ddjvu_page_create_by_pageno(lc->document, pagenum); /*  0? */
593
594         /* pump data untill the page is ready for rendering. */
595         tag=(-1);
596         do {
597                 while ((message = ddjvu_message_peek(lc->context)))
598                         {
599                                 tag=process_message(message);
600                                 if (tag == 0) break;
601                                 ddjvu_message_pop(lc->context);
602                         }
603                 /* fixme: maybe exit? */
604                 /* if (lc->error) break; */
605
606                 message = pump_data_until_message(lc,image);
607                 if (message)
608                         do {
609                                 tag=process_message(message);
610                                 if (tag == 0) break;
611                                 ddjvu_message_pop(lc->context);
612                         } while ((message = ddjvu_message_peek(lc->context)));
613         } while (!ddjvu_page_decoding_done(lc->page));
614
615         ddjvu_document_get_pageinfo(lc->document, pagenum, &info);
616
617         image->resolution.x = (float) info.dpi;
618         image->resolution.y =(float) info.dpi;
619         if (image_info->density != (char *) NULL)
620           {
621             int
622               flags;
623
624             GeometryInfo
625               geometry_info;
626
627             /*
628               Set rendering resolution.
629             */
630             flags=ParseGeometry(image_info->density,&geometry_info);
631             image->resolution.x=geometry_info.rho;
632             image->resolution.y=geometry_info.sigma;
633             if ((flags & SigmaValue) == 0)
634               image->resolution.y=image->resolution.x;
635             info.width*=image->resolution.x/info.dpi;
636             info.height*=image->resolution.y/info.dpi;
637             info.dpi=(ssize_t) MagickMax(image->resolution.x,image->resolution.y);
638           }
639         type = ddjvu_page_get_type(lc->page);
640
641         /* double -> float! */
642         /* image->gamma = (float)ddjvu_page_get_gamma(lc->page); */
643
644         /* mmc:  set  image->depth  */
645         /* mmc:  This from the type */
646
647         image->columns=(size_t) info.width;
648         image->rows=(size_t) info.height;
649
650         /* mmc: bitonal should be palettized, and compressed! */
651         if (type == DDJVU_PAGETYPE_BITONAL){
652                 image->colorspace = GRAYColorspace;
653                 image->storage_class = PseudoClass;
654                 image->depth =  8UL;    /* i only support that? */
655                 image->colors= 2;
656                 if (AcquireImageColormap(image,image->colors,exception) == MagickFalse)
657                   ThrowReaderException(ResourceLimitError,
658                    "MemoryAllocationFailed");
659         } else {
660                 image->colorspace = RGBColorspace;
661                 image->storage_class = DirectClass;
662                 /* fixme:  MAGICKCORE_QUANTUM_DEPTH ?*/
663                 image->depth =  8UL;    /* i only support that? */
664
665                 image->alpha_trait = BlendPixelTrait;
666                 /* is this useful? */
667         }
668 #if DEBUG
669         printf("now filling %.20g x %.20g\n",(double) image->columns,(double)
670           image->rows);
671 #endif
672
673
674 #if 1                           /* per_line */
675
676         /* q = QueueAuthenticPixels(image,0,0,image->columns,image->rows); */
677         get_page_image(lc, lc->page, 0, 0, info.width, info.height, image_info,
678           exception);
679 #else
680         int i;
681         for (i = 0;i< image->rows; i++)
682                 {
683                         printf("%d\n",i);
684                         q = QueueAuthenticPixels(image,0,i,image->columns,1);
685                         get_page_line(lc, i, quantum_info);
686                         SyncAuthenticPixels(image);
687                 }
688
689 #endif /* per_line */
690
691
692 #if DEBUG
693         printf("END: finished filling %.20g x %.20g\n",(double) image->columns,
694           (double) image->rows);
695 #endif
696
697         if (!image->ping)
698           SyncImage(image,exception);
699         /* mmc: ??? Convert PNM pixels to runlength-encoded MIFF packets. */
700         /* image->colors =  */
701
702         /* how is the line padding  / stride? */
703
704         if (lc->page) {
705                 ddjvu_page_release(lc->page);
706                 lc->page = NULL;
707         }
708
709         /* image->page.y=mng_info->y_off[mng_info->object_id]; */
710         if (tag == 0)
711           image=DestroyImage(image);
712         return image;
713         /* end of reading one DJVU page/image */
714 }
715
716 #if 0
717 /* palette */
718   if (AcquireImageColormap(image,2,exception) == MagickFalse)
719     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
720   /*
721     Monochrome colormap.   mmc: this the default!
722   */
723   image->colormap[0].red=QuantumRange;
724   image->colormap[0].green=QuantumRange;
725   image->colormap[0].blue=QuantumRange;
726   image->colormap[1].red=0;
727   image->colormap[1].green=0;
728   image->colormap[1].blue=0;
729 #endif
730
731 static void djvu_close_lc(LoadContext* lc)
732 {
733         if (lc->document)
734                 ddjvu_document_release(lc->document);
735         if (lc->context)
736                 ddjvu_context_release(lc->context);
737         if (lc->page)
738                 ddjvu_page_release(lc->page);
739         RelinquishMagickMemory(lc);
740 }
741
742 static Image *ReadDJVUImage(const ImageInfo *image_info,
743   ExceptionInfo *exception)
744 {
745   const char
746     *url;
747
748   ddjvu_message_t
749     *message;
750
751   Image
752     *image,
753     *images;
754
755   int
756     logging,
757     use_cache;
758
759   LoadContext
760     *lc;
761
762   MagickBooleanType
763     status;
764
765   register ssize_t
766     i;
767
768   /*
769    * Open image file.
770    */
771   assert(image_info != (const ImageInfo *) NULL);
772   assert(image_info->signature == MagickSignature);
773
774
775   if (image_info->debug != MagickFalse)
776     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s", image_info->filename);
777
778   assert(exception != (ExceptionInfo *) NULL);
779   assert(exception->signature == MagickSignature);
780
781
782   logging = LogMagickEvent(CoderEvent,GetMagickModule(),"enter ReadDJVUImage()");
783   (void) logging;
784
785   image = AcquireImage(image_info,exception); /* mmc: ?? */
786
787
788   lc = (LoadContext *) NULL;
789   status = OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
790   if (status == MagickFalse)
791     ThrowReaderException(FileOpenError,"UnableToOpenFile");
792   /*
793     Verify DJVU signature.
794   */
795 #if 0
796   count = ReadBlob(image,8,(unsigned char *) magic_number);
797
798   /* IsDJVU(const unsigned char *magick,const size_t length) */
799   if (memcmp(magic_number,"AT&TFORM",8) != 0)
800     ThrowReaderException(CorruptImageError,"ImproperImageHeader");
801 #endif
802
803
804   /*
805    * Allocate a LoadContext structure.
806    */
807   lc = (LoadContext *) AcquireMagickMemory(sizeof(*lc));
808   if (lc == NULL)
809     ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
810
811
812   /*
813    * Initialize members of the MngInfo structure.
814    */
815   (void) ResetMagickMemory(lc,0,sizeof(LoadContext));
816
817   lc->image = image;
818   lc->pages = 0;
819   lc->context = ddjvu_context_create("ImageMagick djvu loader"); /* g_program_name */
820
821   ddjvu_cache_set_size(lc->context, 1); /* right? */
822   use_cache = 0;
823   /* document: here we don't have a filename, but, for the sake of generality, a FILE* ! */
824   url="http://www.imagemagick.org/fake.djvu";
825   lc->document = ddjvu_document_create(lc->context, url, use_cache); /* don't cache */
826   ddjvu_document_set_user_data(lc->document, lc);
827
828
829   /* now we wait the message-request for data: */
830   message = ddjvu_message_wait(lc->context);
831
832   if (message->m_any.tag != DDJVU_NEWSTREAM) {
833           /* fixme: the djvu context, document! */
834
835           ddjvu_document_release(lc->document);
836           ddjvu_context_release(lc->context);
837
838           RelinquishMagickMemory(lc);
839
840           ThrowReaderException(ResourceLimitError,"Djvu initial message: unexpected type");
841           return NULL;    /* error! */
842   };
843
844   lc->streamid = message->m_newstream.streamid;
845   ddjvu_message_pop(lc->context);
846
847   message = pump_data_until_message(lc,image);
848   /* now process the messages: */
849
850
851   if (message) do {
852           process_message(message);
853           ddjvu_message_pop(lc->context);
854   } while ((message = ddjvu_message_peek(lc->context)));
855
856   /* fixme: i hope we have not read any messages pertinent(?) related to the page itself!  */
857
858   while (lc->pages == 0) {
859           message = ddjvu_message_wait(lc->context);
860           process_message(message);
861           ddjvu_message_pop(lc->context);
862   }
863
864   images=NewImageList();
865   i=0;
866   if (image_info->number_scenes != 0)
867     i=image_info->scene;
868   for ( ; i < (ssize_t) lc->pages; i++)
869   {
870     image=ReadOneDJVUImage(lc,i,image_info,exception);
871     if (image == (Image *) NULL)
872       break;
873     image->scene=i;
874     AppendImageToList(&images,CloneImageList(image,exception));
875     images->extent=GetBlobSize(image);
876     if (image_info->number_scenes != 0)
877       if (image->scene >= (image_info->scene+image_info->number_scenes-1))
878         break;
879   }
880   djvu_close_lc(lc);
881   (void) CloseBlob(images);
882   if (image != (Image *) NULL)
883     image=DestroyImageList(image);
884
885 #if 0
886   if ((image->page.width == 0) && (image->page.height == 0))
887     {
888       image->page.width = image->columns+image->page.x;
889       image->page.height = image->rows+image->page.y;
890     }
891   if (image->columns == 0 || image->rows == 0)
892     {
893       if (logging != MagickFalse)
894         (void) LogMagickEvent(CoderEvent,GetMagickModule(),
895           "exit ReadDJVUImage() with error.");
896       ThrowReaderException(CorruptImageError,"CorruptImage");
897     }
898
899   if (logging != MagickFalse)
900     (void) LogMagickEvent(CoderEvent,GetMagickModule(),"exit ReadDJVUImage()");
901 #endif
902
903
904   return(GetFirstImageInList(images));
905 }
906 #endif
907 \f
908 /*
909 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
910 %                                                                             %
911 %                                                                             %
912 %                                                                             %
913 %   R e g i s t e r D J V U I m a g e                                         %
914 %                                                                             %
915 %                                                                             %
916 %                                                                             %
917 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
918 %
919 %  RegisterDJVUImage() adds attributes for the DJVU image format to
920 %  the list of supported formats.  The attributes include the image format
921 %  tag, a method to read and/or write the format, whether the format
922 %  supports the saving of more than one frame to the same file or blob,
923 %  whether the format supports native in-memory I/O, and a brief
924 %  description of the format.
925 %
926 %  The format of the RegisterDJVUImage method is:
927 %
928 %      size_t RegisterDJVUImage(void)
929 %
930 */
931 ModuleExport size_t RegisterDJVUImage(void)
932 {
933   char
934     version[MaxTextExtent];
935
936   MagickInfo
937     *entry;
938
939   static const char
940     *DJVUNote =
941     {
942       "See http://www.djvuzone.org/ for details about the DJVU format.  The\n"
943       "DJVU 1.2 specification is available there and at\n"
944       "ftp://swrinde.nde.swri.edu/pub/djvu/documents/."
945     };
946
947   *version='\0';
948 #if defined(DJVU_LIBDJVU_VER_STRING)
949   (void) ConcatenateMagickString(version,"libdjvu ",MaxTextExtent);
950   (void) ConcatenateMagickString(version,DJVU_LIBDJVU_VER_STRING,MaxTextExtent);
951 #endif
952   entry=SetMagickInfo("DJVU");
953 #if defined(MAGICKCORE_DJVU_DELEGATE)
954   entry->decoder=(DecodeImageHandler *) ReadDJVUImage;
955 #endif
956   entry->raw=MagickTrue;
957   entry->magick=(IsImageFormatHandler *) IsDJVU;
958   entry->adjoin=MagickFalse;
959   entry->thread_support=MagickTrue;
960   entry->description=AcquireString("Déjà vu");
961   entry->module=AcquireString("DJVU");
962   if (*version != '\0')
963     entry->version=AcquireString(version);
964   entry->note=AcquireString(DJVUNote);
965   (void) RegisterMagickInfo(entry);
966   return(MagickImageCoderSignature);
967 }
968 \f
969 /*
970 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
971 %                                                                             %
972 %                                                                             %
973 %                                                                             %
974 %   U n r e g i s t e r D J V U I m a g e                                     %
975 %                                                                             %
976 %                                                                             %
977 %                                                                             %
978 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
979 %
980 %  UnregisterDJVUImage() removes format registrations made by the
981 %  DJVU module from the list of supported formats.
982 %
983 %  The format of the UnregisterDJVUImage method is:
984 %
985 %      UnregisterDJVUImage(void)
986 %
987 */
988 ModuleExport void UnregisterDJVUImage(void)
989 {
990   (void) UnregisterMagickInfo("DJVU");
991 }