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/* //C- ------------------------------------------------------------------- //C- DjVuLibre-3.5 //C- Copyright (c) 2002 Leon Bottou and Yann Le Cun. //C- Copyright (c) 2001 AT&T //C- //C- This software is subject to, and may be distributed under, the //C- GNU General Public License, either Version 2 of the license, //C- or (at your option) any later version. The license should have //C- accompanied the software or you may obtain a copy of the license //C- from the Free Software Foundation at http://www.fsf.org . //C- //C- This program is distributed in the hope that it will be useful, //C- but WITHOUT ANY WARRANTY; without even the implied warranty of //C- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //C- GNU General Public License for more details. //C- //C- DjVuLibre-3.5 is derived from the DjVu(r) Reference Library from //C- Lizardtech Software. Lizardtech Software has authorized us to //C- replace the original DjVu(r) Reference Library notice by the following //C- text (see doc/lizard2002.djvu and doc/lizardtech2007.djvu): //C- //C- ------------------------------------------------------------------ //C- | DjVu (r) Reference Library (v. 3.5) //C- | Copyright (c) 1999-2001 LizardTech, Inc. All Rights Reserved. //C- | The DjVu Reference Library is protected by U.S. Pat. No. //C- | 6,058,214 and patents pending. //C- | //C- | This software is subject to, and may be distributed under, the //C- | GNU General Public License, either Version 2 of the license, //C- | or (at your option) any later version. The license should have //C- | accompanied the software or you may obtain a copy of the license //C- | from the Free Software Foundation at http://www.fsf.org . //C- | //C- | The computer code originally released by LizardTech under this //C- | license and unmodified by other parties is deemed "the LIZARDTECH //C- | ORIGINAL CODE." Subject to any third party intellectual property //C- | claims, LizardTech grants recipient a worldwide, royalty-free, //C- | non-exclusive license to make, use, sell, or otherwise dispose of //C- | the LIZARDTECH ORIGINAL CODE or of programs derived from the //C- | LIZARDTECH ORIGINAL CODE in compliance with the terms of the GNU //C- | General Public License. This grant only confers the right to //C- | infringe patent claims underlying the LIZARDTECH ORIGINAL CODE to //C- | the extent such infringement is reasonably necessary to enable //C- | recipient to make, have made, practice, sell, or otherwise dispose //C- | of the LIZARDTECH ORIGINAL CODE (or portions thereof) and not to //C- | any greater extent that may be necessary to utilize further //C- | modifications or combinations. //C- | //C- | The LIZARDTECH ORIGINAL CODE is provided "AS IS" WITHOUT WARRANTY //C- | OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED //C- | TO ANY WARRANTY OF NON-INFRINGEMENT, OR ANY IMPLIED WARRANTY OF //C- | MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. //C- +------------------------------------------------------------------ */ #ifndef DDJVUAPI_H #define DDJVUAPI_H #ifdef __cplusplus extern "C" { #endif #if 0 } #endif #include <stddef.h> #include <stdlib.h> #include <stdio.h> #ifndef DDJVUAPI # ifdef _WIN32 # ifdef DDJVUAPI_EXPORT # define DDJVUAPI __declspec(dllexport) # else # define DDJVUAPI __declspec(dllimport) # endif # endif #endif #ifndef DDJVUAPI # define DDJVUAPI /**/ #endif #ifndef TRUE # define TRUE (1) #endif #ifndef FALSE # define FALSE (0) #endif /* -------------------------------------------------- */ /* DDJVU API */ /* -------------------------------------------------- */ /* The DDJVU API provides for efficiently decoding and displaying DjVu documents. It provides for displaying images without waiting for the complete DjVu data. Images can be displayed as soon as sufficient data is available. A higher quality image might later be displayed when further data is available. The DjVu library achieves this using a complicated scheme involving multiple threads. The DDJVU API hides this complexity with a familiar event model. */ /* Compiler symbol DDJVUAPI_VERSION tracks backward compatible additions to the DDJVU API. Version Change ----------------------------- 24 Added: miniexp_lstring() miniexp_to_lstr() 23 Added: miniexp_mutate() 22 Changed miniexp strings accept unicode escapes deprecated miniexp_io_t::p_print7bits added miniexp_io_t::p_flags 21 Added: reentrant version of miniexp input/output 20 Added: ddjvu_get_version_string() ddjvu_format_set_white() ddjvu_anno_get_xmp() 19 Added: ddjvu_document_create_by_filename_utf8() 18 Added: ddjvu_document_get_{anno,pagedump,filedump}() Modifed (binary compatible): ddjvu_document_get_{fileinfo,pageinfo}() ddjvu_document_save() [--pages, --indirect=] Deprecated: ddjvu_document_search_pageno() ddjvu_page_get_{short,long}_description() 17 Added: ddjvu_page_get_initial_rotation(), ddjvu_code_get_version() ddjvu_document_{get_filenum,get_fileinfo}}() ddjvu_document_{search_pageno,check_pagedata}() ddjvu_rectmapper_t and related functions. 16 Added: miniexp.h and related functions. 15 Added: ddjvu_document_get_pageinfo() ddjvu_document_print() 14 Initial version. */ #define DDJVUAPI_VERSION 23 typedef struct ddjvu_context_s ddjvu_context_t; typedef union ddjvu_message_s ddjvu_message_t; typedef struct ddjvu_job_s ddjvu_job_t; typedef struct ddjvu_document_s ddjvu_document_t; typedef struct ddjvu_page_s ddjvu_page_t; typedef struct ddjvu_format_s ddjvu_format_t; typedef struct ddjvu_rect_s ddjvu_rect_t; typedef struct ddjvu_rectmapper_s ddjvu_rectmapper_t; /* GENERAL CONVENTIONS: - all strings use locale encoding (unless specified otherwise). - all filenames are unencoded byte strings, - all errors are signaled with error event messages, - all functions returning a pointer might return a null pointer. HEADER: Always use the following idiom to include this file. #include <libdjvu/ddjvuapi.h> #include <libdjvu/miniexp.h> This file does not declare functions ddjvu_get_DjVuImage() and djvu_get_DjVuDocument() unless you include files "DjVuImage.h" and "DjVuDocument.h" before this file. PREREQUISITES: - Please read the djvu man page: <"tools/djvu.1">. - Please browse the file format specifications <"doc/djvu3changes.txt"> and <"doc/djvu3spec.djvu">. */ /* -------------------------------------------------- */ /* DDJVU_CONTEXT_T */ /* -------------------------------------------------- */ /* There is usually only one <ddjvu_context_t> object. This object holds global data structures such as the cache of decoded pages, or the list of pending event messages. */ /* ddjvu_get_version_string() --- Returns a string that described the underlying code. */ DDJVUAPI const char* ddjvu_get_version_string(void); /* ddjvu_context_create --- Creates a <ddjvu_context_t> object. Argument <programname> is the name of the calling executable. */ DDJVUAPI ddjvu_context_t * ddjvu_context_create(const char *programname); /* ddjvu_context_release --- Release a reference to a <ddjvu_context_t> object. The calling program should no longer reference this object. The object itself will be destroyed as soon as no other object or thread needs it. */ DDJVUAPI void ddjvu_context_release(ddjvu_context_t *context); /* ------- CACHE ------- */ /* ddjvu_cache_set_size --- Sets the maximum size of the cache of decoded page data. The argument is expressed in bytes. */ DDJVUAPI void ddjvu_cache_set_size(ddjvu_context_t *context, unsigned long cachesize); /* ddjvu_cache_get_size --- Returns the maximum size of the cache. */ DDJVUAPI unsigned long ddjvu_cache_get_size(ddjvu_context_t *context); /* ddjvu_cache_clear --- Clears all cached data. */ DDJVUAPI void ddjvu_cache_clear(ddjvu_context_t *context); /* ------- MESSAGE QUEUE ------- */ /* Messages produced by the ddjvu api accumulate into the message queue. Processing messages is not optional! A typical message handling routine looks like this: void handle_ddjvu_messages(ddjvu_context_t *ctx, int wait) { const ddjvu_message_t *msg; if (wait) ddjvu_message_wait(ctx); while ((msg = ddjvu_message_peek(ctx))) { switch(msg->m_any.tag) { case DDJVU_ERROR: .... ; break; case DDJVU_INFO: .... ; break; case DDJVU_NEWSTREAM: .... ; break; .... default: break; } ddjvu_message_pop(ctx); } } */ /* ddjvu_message_peek --- Returns a pointer to the next DDJVU message. This function returns 0 if no message is available. It does not remove the message from the queue. */ DDJVUAPI ddjvu_message_t * ddjvu_message_peek(ddjvu_context_t *context); /* ddjvu_message_wait --- Returns a pointer to the next DDJVU message. This function waits until a message is available. It does not remove the message from the queue. */ DDJVUAPI ddjvu_message_t * ddjvu_message_wait(ddjvu_context_t *context); /* ddjvu_message_pop --- Removes one message from the queue. This function must be called after processing the message. Pointers returned by previous calls to <ddjvu_message_peek> or <ddjvu_message_wait> are no longer valid after calling <ddjvu_message_pop>. */ DDJVUAPI void ddjvu_message_pop(ddjvu_context_t *context); /* ddjvu_message_set_callback --- Defines a callback function invoked whenever a new message is posted to the ddjvuapi message queue, and returns a pointer to the previous callback function. This callback function can be called at any time while other code is executing. Do not call ddjvuapi functions from this callback. It should simply signal the main application event loop that new ddjvuapi messages are available. Under WIN32, this is usually achieved by posting a user window message. Under UNIX, this is usually achieved using a pipe: the callback writes a single byte into the pipe; the main application loop monitors the reading end of the pipe and detects the presence of data. */ typedef void (*ddjvu_message_callback_t)(ddjvu_context_t *context, void *closure); DDJVUAPI void ddjvu_message_set_callback(ddjvu_context_t *context, ddjvu_message_callback_t callback, void *closure); /* -------------------------------------------------- */ /* DDJVU_JOB_T */ /* -------------------------------------------------- */ /* Many essential ddjvuapi functions initiate asynchronous operations. These "jobs" run in seperate threads and report their progress by posting messages into the ddjvu context event queue. Jobs are sometimes represented by a ddjvu_job_t object. */ /* ddjvu_job_status --- Returns the status of the specified job. */ typedef enum { DDJVU_JOB_NOTSTARTED, /* operation was not even started */ DDJVU_JOB_STARTED, /* operation is in progress */ DDJVU_JOB_OK, /* operation terminated successfully */ DDJVU_JOB_FAILED, /* operation failed because of an error */ DDJVU_JOB_STOPPED /* operation was interrupted by user */ } ddjvu_status_t; DDJVUAPI ddjvu_status_t ddjvu_job_status(ddjvu_job_t *job); #define ddjvu_job_done(job) \ (ddjvu_job_status(job) >= DDJVU_JOB_OK) #define ddjvu_job_error(job) \ (ddjvu_job_status(job) >= DDJVU_JOB_FAILED) /* ddjvu_job_stop --- Attempts to cancel the specified job. This is a best effort function. There no guarantee that the job will actually stop. */ DDJVUAPI void ddjvu_job_stop(ddjvu_job_t *job); /* ddjvu_job_set_user_data --- ddjvu_job_get_user_data --- Each job can store an arbitrary pointer that callers can use for any purpose. These two functions provide for accessing or setting this pointer. This pointer is cleared when the job is released */ DDJVUAPI void ddjvu_job_set_user_data(ddjvu_job_t *job, void *userdata); DDJVUAPI void * ddjvu_job_get_user_data(ddjvu_job_t *job); /* ddjvu_job_release --- Releases a reference to a job object and clears its user data field. This does not cause the job to stop executing. The calling program should no longer reference this object. The object itself will be destroyed as soon as no other object or thread needs it. */ DDJVUAPI void ddjvu_job_release(ddjvu_job_t *job); /* -------------------------------------------------- */ /* DDJVU_MESSAGE_T */ /* -------------------------------------------------- */ /* ddjvu_message_t --- This union type represents messages delivered by the DDJVU API. Each member of the union pertains to a specific kind of message. Member <m_any> represents the information common to all kinds of messages. Given a pointer <p> to a <djvu_message_t>, the message kind can be accessed as <"p->m_any.tag">. */ /* ddjvu_message_tag_t --- This enumerated type identifies each kind of message delivered by the DDJVU API. */ typedef enum { DDJVU_ERROR, DDJVU_INFO, DDJVU_NEWSTREAM, DDJVU_DOCINFO, DDJVU_PAGEINFO, DDJVU_RELAYOUT, DDJVU_REDISPLAY, DDJVU_CHUNK, DDJVU_THUMBNAIL, DDJVU_PROGRESS, } ddjvu_message_tag_t; /* ddjvu_message_t::m_any --- This structure is a member of the union <djvu_message_t>. It represents the information common to all kinds of messages. Member <tag> indicates the kind of message. Members <context>, <document>, <page>, and <job> indicate the origin of the message. These fields contain null pointers when they are not relevant. These fields are also cleared when the corresponding object is released with <ddjvu_{job,page,document}_release>. If the message has not yet been passed to the user with <ddjvu_message_{peek,wait}>, it is silently removed from the message queue. */ typedef struct ddjvu_message_any_s { ddjvu_message_tag_t tag; ddjvu_context_t *context; ddjvu_document_t *document; ddjvu_page_t *page; ddjvu_job_t *job; } ddjvu_message_any_t; /* ddjvu_message_t::m_error --- Error messages are generated whenever the decoder or the DDJVU API encounters an error condition. All errors are reported as error messages because they can occur asynchronously. Member <message> is the error message. Members <function>, <filename> and <lineno> indicates the place where the error was detected. */ struct ddjvu_message_error_s { /* ddjvu_message_t::m_error */ ddjvu_message_any_t any; const char *message; const char *function; const char *filename; int lineno; }; /* ddjvu_message_t::m_info --- This messages provides informational text indicating the progress of the decoding process. This might be displayed in the browser status bar. */ struct ddjvu_message_info_s { /* ddjvu_message_t::m_info */ ddjvu_message_any_t any; const char *message; }; /* -------------------------------------------------- */ /* DDJVU_DOCUMENT_T */ /* -------------------------------------------------- */ /* ddjvu_document_create --- Creates a decoder for a DjVu document and starts decoding. This function returns immediately. The decoding job then generates messages to request the raw data and to indicate the state of the decoding process. Argument <url> specifies an optional URL for the document. The URL follows the usual syntax (<"protocol://machine/path">). It should not end with a slash. It only serves two purposes: - The URL is used as a key for the cache of decoded pages. - The URL is used to document <m_newstream> messages. Setting argument <cache> to <TRUE> indicates that decoded pages should be cached when possible. This only works when argument <url> is not the null pointer. It is important to understand that the URL is not used to access the data. The document generates <m_newstream> messages to indicate which data is needed. The caller must then provide the raw data using <ddjvu_stream_write> and <ddjvu_stream_close>. Localized characters in argument <url> should be in urlencoded UTF-8 (like "%2A"). What is happening for non ascii characters is unclear (probably UTF-8). */ DDJVUAPI ddjvu_document_t * ddjvu_document_create(ddjvu_context_t *context, const char *url, int cache); /* ddjvu_document_create_by_filename --- Creates a document for a DjVu document stored in a file. The document will directly access the specified DjVu file or related files without generating <m_newstream> messages. The standard function expects the filename in locale encoding. The utf8 variant expects an utf8 encoded filename. */ DDJVUAPI ddjvu_document_t * ddjvu_document_create_by_filename(ddjvu_context_t *context, const char *filename, int cache); DDJVUAPI ddjvu_document_t * ddjvu_document_create_by_filename_utf8(ddjvu_context_t *context, const char *filename, int cache); /* ddjvu_document_job --- Access the job object in charge of decoding the document header. In fact <ddjvu_document_t> is a subclass of <ddjvu_job_t> and this function is a type cast. */ DDJVUAPI ddjvu_job_t * ddjvu_document_job(ddjvu_document_t *document); /* ddjvu_document_release --- Release a reference to a <ddjvu_document_t> object. The calling program should no longer reference this object. The object itself will be destroyed as soon as no other object or thread needs it. */ #define ddjvu_document_release(document) \ ddjvu_job_release(ddjvu_document_job(document)) /* ddjvu_document_set_user_data --- ddjvu_document_get_user_data --- Each <ddjvu_document_t> object can store an arbitray pointer that callers can use for any purpose. These two functions provide for accessing or setting this pointer. */ #define ddjvu_document_set_user_data(document,userdata) \ ddjvu_job_set_user_data(ddjvu_document_job(document),userdata) #define ddjvu_document_get_user_data(document) \ ddjvu_job_get_user_data(ddjvu_document_job(document)) /* ddjvu_document_decoding_status --- ddjvu_document_decoding_done, ddjvu_document_decoding_error --- This function returns the status of the document header decoding job */ #define ddjvu_document_decoding_status(document) \ ddjvu_job_status(ddjvu_document_job(document)) #define ddjvu_document_decoding_done(document) \ (ddjvu_document_decoding_status(document) >= DDJVU_JOB_OK) #define ddjvu_document_decoding_error(document) \ (ddjvu_document_decoding_status(document) >= DDJVU_JOB_FAILED) /* ------- STREAMS ------- */ /* ddjvu_message_t::m_newstream --- Newstream messages are generated whenever the decoder needs to access raw DjVu data. The caller must then provide the requested data using <ddjvu_stream_write> and <ddjvu_stream_close>. In the case of indirect documents, a single decoder might simultaneously request several streams of data. Each stream is identified by a small integer <streamid>. The first <m_newstream> message always has member <streamid> set to zero and member <name> set to the null pointer. It indicates that the decoder needs to access the data in the main DjVu file. In fact, data can be written to stream <0> as soon as the <ddjvu_document_t> object is created. Further <m_newstream> messages are generated to access the auxiliary files of indirect or indexed DjVu documents. Member <name> then provides the basename of the auxiliary file. Member <url> is set according to the url argument provided to function <ddjvu_document_create>. The first newstream message always contain the url passed to <ddjvu_document_create>. Subsequent newstream messages contain the url of the auxiliary files for indirect or indexed DjVu documents. */ struct ddjvu_message_newstream_s { /* ddjvu_message_t::m_newstream */ ddjvu_message_any_t any; int streamid; const char *name; const char *url; }; /* ddjvu_stream_write --- Provide raw data to the DjVu decoder. This function should be called as soon as the data is available, for instance when receiving DjVu data from a network connection. */ DDJVUAPI void ddjvu_stream_write(ddjvu_document_t *document, int streamid, const char *data, unsigned long datalen ); /* ddjvu_stream_close --- Indicates that no more data will be provided on a particular stream. Argument <stop> most likely should be set to <FALSE>. Setting argument <stop> to <TRUE> indicates that the user has interrupted the data transfer (for instance by pressing the stop button of a browser) and that the decoding threads should be stopped as soon as feasible. */ DDJVUAPI void ddjvu_stream_close(ddjvu_document_t *document, int streamid, int stop ); /* ------- QUERIES ------- */ /* ddjvu_message_t::m_docinfo --- The <m_docinfo> message indicates that basic information about the document has been obtained and decoded. Not much can be done before this happens. Call <ddjvu_document_decoding_status> to determine whether the operation was successful. */ struct ddjvu_message_docinfo_s { ddjvu_message_any_t any; }; /* ddjvu_document_get_type --- Returns the type of a DjVu document. This function might return <DDJVU_DOCTYPE_UNKNOWN> when called before receiving a <m_docinfo> message. */ typedef enum { DDJVU_DOCTYPE_UNKNOWN=0, DDJVU_DOCTYPE_SINGLEPAGE, DDJVU_DOCTYPE_BUNDLED, DDJVU_DOCTYPE_INDIRECT, DDJVU_DOCTYPE_OLD_BUNDLED, /* obsolete */ DDJVU_DOCTYPE_OLD_INDEXED, /* obsolete */ } ddjvu_document_type_t; DDJVUAPI ddjvu_document_type_t ddjvu_document_get_type(ddjvu_document_t *document); /* ddjvu_document_get_pagenum --- Returns the number of pages in a DjVu document. This function might return 1 when called before receiving a <m_docinfo> message */ DDJVUAPI int ddjvu_document_get_pagenum(ddjvu_document_t *document); /* ------- ADVANCED ------- */ /* ddjvu_document_get_filenum -- Returns the number of component files. This function might return 0 when called before receiving a <m_docinfo> message */ DDJVUAPI int ddjvu_document_get_filenum(ddjvu_document_t *document); /* ddjvu_document_get_fileinfo -- Returns information about component file <fileno>. This function might return <DDJVU_JOB_STARTED> when called before receiving a <m_docinfo> message. String pointers in the returned data structure might be null. Strings are UTF8 encoded and remain allocated as long as the ddjvu_document_t object exists. Changes for ddjvuapi=18 - Redefined as a macro passing the structure size. */ typedef struct ddjvu_fileinfo_s { char type; /* [P]age, [T]humbnails, [I]nclude. */ int pageno; /* Negative when not applicable. */ int size; /* Negative when unknown. */ const char *id; /* File identifier. */ const char *name; /* Name for indirect documents. */ const char *title; /* Page title. */ } ddjvu_fileinfo_t; #define ddjvu_document_get_fileinfo(d,f,i) \ ddjvu_document_get_fileinfo_imp(d,f,i,sizeof(ddjvu_fileinfo_t)) DDJVUAPI ddjvu_status_t ddjvu_document_get_fileinfo_imp(ddjvu_document_t *document, int fileno, ddjvu_fileinfo_t *info, unsigned int infosz); /* ddjvu_document_search_pageno --- DEPRECATED. */ DDJVUAPI int ddjvu_document_search_pageno(ddjvu_document_t*, const char*); /* ddjvu_document_check_pagedata --- Returns a non zero result if the data for page <pageno> is already in memory. When this is the case, functions <ddjvu_document_get_pageinfo> and <ddjvu_document_get_pagetext> return the information immediately. This function causes the emission of <m_pageinfo> messages with zero in the <m_any.page> field whenever a new file is completely downloaded. */ DDJVUAPI int ddjvu_document_check_pagedata(ddjvu_document_t *document, int pageno); /* ddjvu_document_get_pageinfo --- Attempts to obtain information about page <pageno> without decoding the page. If the information is available, the function returns <DDJVU_JOB_OK> and fills the <info> structure. Otherwise it starts fetching page data and returns <DDJVU_JOB_STARTED>. This function causes the emission of <m_pageinfo> messages with zero in the <m_any.page> field. Typical synchronous usage: ddjvu_status_t r; ddjvu_pageinfo_t info; while ((r=ddjvu_document_get_pageinfo(doc,pageno,&info))<DDJVU_JOB_OK) handle_ddjvu_messages(ctx, TRUE); if (r>=DDJVU_JOB_FAILED) signal_error(); Changes for ddjvuapi=18 - Redefined as a macro passing the structure size. - Added fields 'rotation' and 'version'. */ typedef struct ddjvu_pageinfo_s { int width; /* page width (in pixels) */ int height; /* page height (in pixels) */ int dpi; /* page resolution (in dots per inche) */ int rotation; /* initial page orientation */ int version; /* page version */ } ddjvu_pageinfo_t; #define ddjvu_document_get_pageinfo(d,p,i) \ ddjvu_document_get_pageinfo_imp(d,p,i,sizeof(ddjvu_pageinfo_t)) DDJVUAPI ddjvu_status_t ddjvu_document_get_pageinfo_imp(ddjvu_document_t *document, int pageno, ddjvu_pageinfo_t *info, unsigned int infosz ); /* ddjvu_document_get_pagedump -- This function returns a UTF8 encoded text describing the contents of page <pageno> using the same format as command <djvudump>. The returned string must be deallocated using <free()>. It returns <0> when the information is not yet available. It may then cause then the emission of <m_pageinfo> messages with null <m_any.page>. */ DDJVUAPI char * ddjvu_document_get_pagedump(ddjvu_document_t *document, int pageno); /* ddjvu_document_get_filedump -- This function returns a UTF8 encoded text describing the contents of file <fileno> using the same format as command <djvudump>. The returned string must be deallocated using <free()>. It returns <0> when the information is not yet available. It may then cause then the emission of <m_pageinfo> messages with null <m_any.page>. */ DDJVUAPI char * ddjvu_document_get_filedump(ddjvu_document_t *document, int fileno); /* -------------------------------------------------- */ /* DJVU_PAGE_T */ /* -------------------------------------------------- */ /* ddjvu_page_create_by_pageno --- Each page of a document can be accessed by creating a <ddjvu_page_t> object with this function. Argument <pageno> indicates the page number, starting with page <0> to <pagenum-1>. This function may return NULL when called before receiving the <m_docinfo> message. Calling this function also initiates the data transfer and the decoding threads for the specified page. Various messages will document the progress of these operations. Error messages will be generated if the page does not exists. */ DDJVUAPI ddjvu_page_t * ddjvu_page_create_by_pageno(ddjvu_document_t *document, int pageno); /* ddjvu_page_create_by_pageid --- This function is similar to <ddjvu_page_create_by_pageno> but identifies the desired page by name instead of page number. */ DDJVUAPI ddjvu_page_t * ddjvu_page_create_by_pageid(ddjvu_document_t *document, const char *pageid); /* ddjvu_page_job --- Access the job object in charge of decoding the document header. In fact <ddjvu_page_t> is a subclass of <ddjvu_job_t> and this function is a type cast. */ DDJVUAPI ddjvu_job_t * ddjvu_page_job(ddjvu_page_t *page); /* ddjvu_page_release --- Release a reference to a <ddjvu_page_t> object. The calling program should no longer reference this object. The object itself will be destroyed as soon as no other object or thread needs it. */ #define ddjvu_page_release(page) \ ddjvu_job_release(ddjvu_page_job(page)) /* ddjvu_page_set_user_data --- ddjvu_page_get_user_data --- Each <ddjvu_paqge_t> object can store an arbitray pointer that callers can use for any purpose. These two functions provide for accessing or setting this pointer. */ #define ddjvu_page_set_user_data(page,userdata) \ ddjvu_job_set_user_data(ddjvu_page_job(page),userdata) #define ddjvu_page_get_user_data(page) \ ddjvu_job_get_user_data(ddjvu_page_job(page)) /* ddjvu_page_decoding_status --- ddjvu_page_decoding_done --- ddjvu_page_decoding_error --- These calls return the status of the page decoding job. */ #define ddjvu_page_decoding_status(page) \ ddjvu_job_status(ddjvu_page_job(page)) #define ddjvu_page_decoding_done(page) \ (ddjvu_page_decoding_status(page) >= DDJVU_JOB_OK) #define ddjvu_page_decoding_error(page) \ (ddjvu_page_decoding_status(page) >= DDJVU_JOB_FAILED) /* ------- MESSAGES ------- */ /* ddjvu_message_t::m_pageinfo --- The page decoding process generates this message - when basic page information is available and before any <m_relayout> or <m_redisplay> message, - when the page decoding thread terminates. You can distinguish both cases using function ddjvu_page_decoding_status(). Messages <m_pageinfo> are also generated as a consequence of functions such as <ddjvu_document_get_pageinfo>. The field <m_any.page> of such message is null. */ struct ddjvu_message_pageinfo_s { /* ddjvu_message_t::m_pageinfo */ ddjvu_message_any_t any; }; /* ddjvu_message_t::m_relayout --- This message is generated when a DjVu viewer should recompute the layout of the page viewer because the page size and resolution information has been updated. */ struct ddjvu_message_relayout_s { /* ddjvu_message_t::m_relayout */ ddjvu_message_any_t any; }; /* ddjvu_message_t::m_redisplay --- This message is generated when a DjVu viewer should call <ddjvu_page_render> and redisplay the page. This happens, for instance, when newly decoded DjVu data provides a better image. */ struct ddjvu_message_redisplay_s { /* ddjvu_message_t::m_redisplay */ ddjvu_message_any_t any; }; /* ddjvu_message_t::m_chunk --- This message indicates that an additional chunk of DjVu data has been decoded. Member <chunkid> indicates the type of the DjVu chunk. */ struct ddjvu_message_chunk_s { /* ddjvu_message_t::m_chunk */ ddjvu_message_any_t any; const char *chunkid; }; /* About page messages -- Both the <m_relayout> and <m_redisplay> messages are derived from the <m_chunk> message. They are intended for driving a djvu image viewer. When receiving <m_relayout>, the viewer should get the image size, decide zoom factors, and place the image area, scrollbars, toolbars, and other gui objects. When receiving <m_redisplay>, the viewer should invalidate the image area so that the gui toolkit calls the repaint event handler. This handler should call ddjvu_page_render() and paint the part of the image that needs repainting. */ /* ------- QUERIES ------- */ /* ddjvu_page_get_width --- Returns the page width in pixels. Calling this function before receiving a <m_pageinfo> message always yields <0>. */ DDJVUAPI int ddjvu_page_get_width(ddjvu_page_t *page); /* ddjvu_page_get_height--- Returns the page height in pixels. Calling this function before receiving a <m_pageinfo> message always yields <0>. */ DDJVUAPI int ddjvu_page_get_height(ddjvu_page_t *page); /* ddjvu_page_get_resolution --- Returns the page resolution in pixels per inch (dpi). Calling this function before receiving a <m_pageinfo> message yields a meaningless but plausible value. */ DDJVUAPI int ddjvu_page_get_resolution(ddjvu_page_t *page); /* ddjvu_page_get_gamma --- Returns the gamma of the display for which this page was designed. Calling this function before receiving a <m_pageinfo> message yields a meaningless but plausible value. */ DDJVUAPI double ddjvu_page_get_gamma(ddjvu_page_t *page); /* ddjvu_page_get_version --- Returns the version of the djvu file format. Calling this function before receiving a <m_pageinfo> message yields a meaningless but plausible value. */ DDJVUAPI int ddjvu_page_get_version(ddjvu_page_t *page); /* ddjvu_code_get_version --- Returns the version of the djvu file format implemented by this library. More or less graceful degradation might arise if this is smaller than the number returned by <ddjvu_page_get_version>. */ DDJVUAPI int ddjvu_code_get_version(void); /* ddjvu_page_get_type --- Returns the type of the page data. Calling this function before the termination of the decoding process might returns <DDJVU_PAGETYPE_UNKNOWN>. */ typedef enum { DDJVU_PAGETYPE_UNKNOWN, DDJVU_PAGETYPE_BITONAL, DDJVU_PAGETYPE_PHOTO, DDJVU_PAGETYPE_COMPOUND, } ddjvu_page_type_t; DDJVUAPI ddjvu_page_type_t ddjvu_page_get_type(ddjvu_page_t *page); /* ddjvu_page_get_{short,long}_description --- DEPRECATED */ DDJVUAPI char *ddjvu_page_get_short_description(ddjvu_page_t *); DDJVUAPI char *ddjvu_page_get_long_description(ddjvu_page_t *); /* ddjvu_page_set_rotation --- Changes the counter-clockwise rotation angle for a DjVu page. Calling this function before receiving a <m_pageinfo> message has no good effect. */ typedef enum { DDJVU_ROTATE_0 = 0, DDJVU_ROTATE_90 = 1, DDJVU_ROTATE_180 = 2, DDJVU_ROTATE_270 = 3, } ddjvu_page_rotation_t; DDJVUAPI void ddjvu_page_set_rotation(ddjvu_page_t *page, ddjvu_page_rotation_t rot); /* ddjvu_page_get_rotation --- Returns the counter-clockwise rotation angle for the DjVu page. The rotation is automatically taken into account by <ddjvu_page_render>, <ddjvu_page_get_width> and <ddjvu_page_get_height>. */ DDJVUAPI ddjvu_page_rotation_t ddjvu_page_get_rotation(ddjvu_page_t *page); /* ddjvu_page_get_initial_rotation --- Returns the page rotation specified by the orientation flags in the DjVu file. [brain damage warning] This is useful because maparea coordinates in the annotation chunks are expressed relative to the rotated coordinates whereas text coordinates in the hidden text data are expressed relative to the unrotated coordinates. */ DDJVUAPI ddjvu_page_rotation_t ddjvu_page_get_initial_rotation(ddjvu_page_t *page); /* ------- RENDER ------- */ /* ddjvu_render_mode_t --- Various ways to render a page. */ typedef enum { DDJVU_RENDER_COLOR = 0, /* color page or stencil */ DDJVU_RENDER_BLACK, /* stencil or color page */ DDJVU_RENDER_COLORONLY, /* color page or fail */ DDJVU_RENDER_MASKONLY, /* stencil or fail */ DDJVU_RENDER_BACKGROUND, /* color background layer */ DDJVU_RENDER_FOREGROUND, /* color foreground layer */ } ddjvu_render_mode_t; /* ddjvu_rect_t --- This structure specifies the location of a rectangle. Coordinates are usually expressed in pixels relative to the BOTTOM LEFT CORNER (but see ddjvu_format_set_y_direction). Members <x> and <y> indicate the position of the bottom left corner of the rectangle Members <w> and <h> indicate the width and height of the rectangle. */ struct ddjvu_rect_s { int x, y; unsigned int w, h; }; /* ddjvu_page_render -- Renders a segment of a page with arbitrary scale. Argument <mode> indicates what image layers should be rendered. Conceptually this function renders the full page into a rectangle <pagerect> and copies the pixels specified by rectangle <renderrect> into the buffer starting at position <imagebuffer>. The actual code is much more efficient than that. The final image is written into buffer <imagebuffer>. Argument <pixelformat> specifies the expected pixel format. Argument <rowsize> specifies the number of BYTES from one row to the next in the buffer. The buffer must be large enough to accomodate the desired image. This function makes a best effort to compute an image that reflects the most recently decoded data. It might return <FALSE> to indicate that no image could be computed at this point, and that nothing was written into the buffer. */ DDJVUAPI int ddjvu_page_render(ddjvu_page_t *page, const ddjvu_render_mode_t mode, const ddjvu_rect_t *pagerect, const ddjvu_rect_t *renderrect, const ddjvu_format_t *pixelformat, unsigned long rowsize, char *imagebuffer ); /* -------------------------------------------------- */ /* COORDINATE TRANSFORMS */ /* -------------------------------------------------- */ /* ddjvu_rectmapper_create -- Creates a <ddjvu_rectmapper_t> data structure representing an affine coordinate transformation that maps points from rectangle <input> to rectangle <output>. The transformation maintains the positions relative to the coordinates of the rectangle corners. */ DDJVUAPI ddjvu_rectmapper_t * ddjvu_rectmapper_create(ddjvu_rect_t *input, ddjvu_rect_t *output); /* ddjvu_rectmapper_modify --- Modifies the coordinate transform <mapper> by redefining which corners of the output rectangle match those of the input rectangle. This function first applies a counter-clockwise rotation of <rotation> quarter-turns, and then reverses the X (resp. Y) coordinates when <mirrorx> (resp. <mirrory>) is non zero. */ DDJVUAPI void ddjvu_rectmapper_modify(ddjvu_rectmapper_t *mapper, int rotation, int mirrorx, int mirrory); /* ddjvu_rectmapper_release --- Destroys the <ddjvu_rect_mapper_t> structure returned by <ddjvu_rect_mapper_create>. */ DDJVUAPI void ddjvu_rectmapper_release(ddjvu_rectmapper_t *mapper); /* ddjvu_map_point, ddjvu_map_rect --- Applies the coordinate transform to a point or a rectangle */ DDJVUAPI void ddjvu_map_point(ddjvu_rectmapper_t *mapper, int *x, int *y); DDJVUAPI void ddjvu_map_rect(ddjvu_rectmapper_t *mapper, ddjvu_rect_t *rect); /* ddjvu_unmap_point, ddjvu_unmap_rect --- Applies the inverse coordinate transform to a point or a rectangle */ DDJVUAPI void ddjvu_unmap_point(ddjvu_rectmapper_t *mapper, int *x, int *y); DDJVUAPI void ddjvu_unmap_rect(ddjvu_rectmapper_t *mapper, ddjvu_rect_t *rect); /* -------------------------------------------------- */ /* DJVU_FORMAT_T */ /* -------------------------------------------------- */ /* ddjvu_format_style_t --- Enumerated type for pixel formats. */ typedef enum { DDJVU_FORMAT_BGR24, /* truecolor 24 bits in BGR order */ DDJVU_FORMAT_RGB24, /* truecolor 24 bits in RGB order */ DDJVU_FORMAT_RGBMASK16, /* truecolor 16 bits with masks */ DDJVU_FORMAT_RGBMASK32, /* truecolor 32 bits with masks */ DDJVU_FORMAT_GREY8, /* greylevel 8 bits */ DDJVU_FORMAT_PALETTE8, /* paletized 8 bits (6x6x6 color cube) */ DDJVU_FORMAT_MSBTOLSB, /* packed bits, msb on the left */ DDJVU_FORMAT_LSBTOMSB, /* packed bits, lsb on the left */ } ddjvu_format_style_t; /* ddjvu_format_create --- Creates a <ddjvu_format_t> object describing a pixel format. Argument <style> describes the generic pixel format. Argument <args> is an array of <nargs> unsigned ints providing additionnal information: - When style is <RGBMASK*>, argument <nargs> must be <3> or <4>. The three first entries of array <args> are three contiguous bit masks for the red, green, and blue components of each pixel. The resulting color is then xored with the optional fourth entry. - When style is <PALETTE*>, argument <nargs> must be <216> and array <args> contains the 6*6*6 entries of a web color cube. - Otherwise <nargs> must be <0>. */ DDJVUAPI ddjvu_format_t * ddjvu_format_create(ddjvu_format_style_t style, int nargs, unsigned int *args); /* ddjvu_format_set_row_order --- Sets a flag indicating whether the rows in the pixel buffer are stored starting from the top or the bottom of the image. Default ordering starts from the bottom of the image. This is the opposite of the X11 convention. */ DDJVUAPI void ddjvu_format_set_row_order(ddjvu_format_t *format, int top_to_bottom); /* ddjvu_format_set_y_direction --- Sets a flag indicating whether the y coordinates in the drawing area are oriented from bottom to top, or from top to botttom. The default is bottom to top, similar to PostScript. This is the opposite of the X11 convention. */ DDJVUAPI void ddjvu_format_set_y_direction(ddjvu_format_t *format, int top_to_bottom); /* ddjvu_format_set_ditherbits --- Specifies the final depth of the image on the screen. This is used to decide which dithering algorithm should be used. The default is usually appropriate. */ DDJVUAPI void ddjvu_format_set_ditherbits(ddjvu_format_t *format, int bits); /* ddjvu_format_set_gamma --- Sets the gamma of the display for which the pixels are intended. This will be combined with the gamma stored in DjVu documents in order to compute a suitable color correction. The default value is 2.2. */ DDJVUAPI void ddjvu_format_set_gamma(ddjvu_format_t *format, double gamma); /* ddjvu_format_set_white --- Sets the whitepoint of the display for which the pixels are intended. This will be combined with the gamma stored in DjVu documents in order to compute a suitable color correction. The default value is 0xff,0xff,0xff. */ DDJVUAPI void ddjvu_format_set_white(ddjvu_format_t *format, unsigned char b, unsigned char g, unsigned char r); /* ddjvu_format_release --- Release a reference to a <ddjvu_format_t> object. The calling program should no longer reference this object. */ DDJVUAPI void ddjvu_format_release(ddjvu_format_t *format); /* -------------------------------------------------- */ /* THUMBNAILS */ /* -------------------------------------------------- */ /* ddjvu_thumbnail_status --- Determine whether a thumbnail is available for page <pagenum>. Calling this function with non zero argument <start> initiates a thumbnail calculation job. Regardless of its success, the completion of the job is signalled by a subsequent <m_thumbnail> message. */ DDJVUAPI ddjvu_status_t ddjvu_thumbnail_status(ddjvu_document_t *document, int pagenum, int start); /* ddjvu_message_t::m_thumbnail --- This message is sent when additional thumbnails are available. */ struct ddjvu_message_thumbnail_s { /* ddjvu_message_t::m_thumbnail */ ddjvu_message_any_t any; int pagenum; }; /* ddjvu_thumbnail_render --- Renders a thumbnail for page <pagenum>. Argument <imagebuffer> must be large enough to contain an image of size <*wptr> by <*hptr> using pixel format <pixelformat>. Argument <rowsize> specifies the number of BYTES from one row to the next in the buffer. This function returns <FALSE> when no thumbnail is available. Otherwise it returns <TRUE>, adjusts <*wptr> and <*hptr> to reflect the thumbnail size, and, if the pointer <imagebuffer> is non zero, writes the pixel data into the image buffer. */ DDJVUAPI int ddjvu_thumbnail_render(ddjvu_document_t *document, int pagenum, int *wptr, int *hptr, const ddjvu_format_t *pixelformat, unsigned long rowsize, char *imagebuffer); /* -------------------------------------------------- */ /* SAVE AND PRINT JOBS */ /* -------------------------------------------------- */ /* ddjvu_message_t::m_progress --- These messages are generated to indicate progress towards the completion of a print or save job. */ struct ddjvu_message_progress_s { ddjvu_message_any_t any; ddjvu_status_t status; int percent; }; /* ddjvu_document_print --- Converts specified pages of a djvu document into postscript. This function works asynchronously in a separate thread. You can use the following idiom for synchronous operation: ddjvu_job_t *job = ddjvu_document_print(....); while (! ddjvu_job_done(job) ) handle_ddjvu_messages(context, TRUE); The postscript data is written to stdio file <output>. Arguments <optc> and <optv> specify printing options. All options described on the <djvups> man page are recognized, except <"-help"> and <"-verbose">. */ DDJVUAPI ddjvu_job_t * ddjvu_document_print(ddjvu_document_t *document, FILE *output, int optc, const char * const * optv); /* ddjvu_document_save --- Saves the djvu document as a bundled djvu file. This function works asynchronously in a separate thread. You can use the following idiom for synchronous operation: ddjvu_job_t *job = ddjvu_document_save(....); while (! ddjvu_job_done(job) ) handle_ddjvu_messages(context, TRUE); The bundled djvu data is written to file <output> which must be seekable. Arguments <optc> and <optv> can be used to pass the following options: * Option "-pages=<pagespec>" specify a subset of pages using the same syntax as program <ddjvu>. Reordering or duplicating pages is prohibited. * Option "-indirect=<filename>" causes the creation of an indirect document with index file <filename> and auxiliary files in the same directory. The file name is UTF-8 encoded. When this option is specified, the argument <output> is ignored and should be NULL. */ DDJVUAPI ddjvu_job_t * ddjvu_document_save(ddjvu_document_t *document, FILE *output, int optc, const char * const * optv); /* -------------------------------------------------- */ /* S-EXPRESSIONS */ /* -------------------------------------------------- */ /* DjVu files can contain ancillary information such as document outline, hidden text, hyperlinks, and metadata. Program <djvused> provides for manipulating such information. Like <djvused>, the DDJVU API represents this information using a lisp s-expressions. See file <"libdjvu/miniexp.h"> for the s-expression documentation and manipulation functions. See the <djvused> man page for the specification of the s-expressions representing outlines, hidden text and annotations. It often help to print s-expressions using function <miniexp_pprint>. WARNING: All strings in s-expression are UTF-8 encoded. Strings returned by miniexp_to_str might have to be converted to the locale encoding. */ /* miniexp_t -- Opaque type representing s-expressions. The same definition also appears in file <"libdjvu/miniexp.h">. */ #ifndef MINIEXP_H typedef struct miniexp_s* miniexp_t; #endif /* ddjvu_miniexp_release -- This function controls the allocation of the s-expressions returned by functions from the DDJVU API. It indicates that the s-expression <expr> is no longer needed and can be deallocated as soon as necessary. Otherwise the s-expression remains allocated as long as the document object exists. */ DDJVUAPI void ddjvu_miniexp_release(ddjvu_document_t *document, miniexp_t expr); /* ddjvu_document_get_outline -- This function tries to obtain the document outline. If this information is available, it returns a s-expression with the same syntax as function <print-outline> of program <djvused>. Otherwise it returns <miniexp_dummy> until the document header gets fully decoded. Typical synchronous usage: miniexp_t r; while ((r=ddjvu_document_get_outline(doc))==miniexp_dummy) handle_ddjvu_messages(ctx, TRUE); This function returns the empty list <miniexp_nil> when the document contains no outline information. It can also return symbols <failed> or <stopped> when an error occurs while accessing the desired information. */ DDJVUAPI miniexp_t ddjvu_document_get_outline(ddjvu_document_t *document); /* ddjvu_document_get_anno -- This function returns the document-wide annotations. This corresponds to a proposed change in the djvu format. When no new-style document-wide annotations are available and <compat> is true, this function searches a shared annotation chunk and returns its contents. This function returns <miniexp_dummy> if the information is not yet available. It may then cause the emission of <m_pageinfo> messages with null <m_any.page>. This function returns the empty list <miniexp_nil> when the document does not contain page annotations. It can also return symbols <failed> or <stopped> when an error occurs while accessing the desired information. */ DDJVUAPI miniexp_t ddjvu_document_get_anno(ddjvu_document_t *document, int compat); /* ddjvu_document_get_pagetext -- This function tries to obtain the text information for page <pageno>. If this information is available, it returns a s-expression with the same syntax as function <print-txt> of program <djvused>. Otherwise it starts fetching the page data and returns <miniexp_dummy>. This function causes the emission of <m_pageinfo> messages with zero in the <m_any.page> field. Typical synchronous usage: miniexp_t r; while ((r=ddjvu_document_get_pagetext(doc,pageno,0))==miniexp_dummy) handle_ddjvu_messages(ctx, TRUE); This function returns the empty list <miniexp_nil> when the page contains no text information. It can also return symbols <failed> or <stopped> when an error occurs while accessing the desired information. Argument <maxdetail> controls the level of detail in the returned s-expression. Values "page", "column", "region", "para", "line", and "word" restrict the output to the specified granularity. All other values produce a s-expression that represents the hidden text data as finely as possible. */ DDJVUAPI miniexp_t ddjvu_document_get_pagetext(ddjvu_document_t *document, int pageno, const char *maxdetail); /* ddjvu_document_get_pageanno -- This function tries to obtain the annotations for page <pageno>. If this information is available, it returns a s-expression with the same syntax as function <print-ant> of program <djvused>. Otherwise it starts fetching the page data and returns <miniexp_dummy>. This function causes the emission of <m_pageinfo> messages with zero in the <m_any.page> field. Typical synchronous usage: miniexp_t r; while ((r = ddjvu_document_get_pageanno(doc,pageno))==miniexp_dummy) handle_ddjvu_messages(ctx, TRUE); This function returns the empty list <miniexp_nil> when the page contains no annotations. It can also return symbols <failed> or <stopped> when an error occurs while accessing the desired information. */ DDJVUAPI miniexp_t ddjvu_document_get_pageanno(ddjvu_document_t *document, int pageno); /* --- Helper functions to parse annotations --- */ /* ddjvu_anno_get_bgcolor -- Parse the annotations and extracts the desired background color as a color string ("#FFFFFF"). See <(background ...)> in the djvused man page. Returns zero if this information is not specified. */ DDJVUAPI const char * ddjvu_anno_get_bgcolor(miniexp_t annotations); /* ddjvu_anno_get_zoom -- Parse the annotations and extracts the desired zoom factor. See <(zoom ...)> in the djvused man page. Returns zero if this information is not specified. */ DDJVUAPI const char * ddjvu_anno_get_zoom(miniexp_t annotations); /* ddjvu_anno_get_mode -- Parse the annotations and extracts the desired display mode. See <(mode ...)> in the djvused man page. Returns zero if this information is not specified. */ DDJVUAPI const char * ddjvu_anno_get_mode(miniexp_t annotations); /* ddjvu_anno_get_horizalign -- Parse the annotations and extracts how the page image should be aligned horizontally. See <(align ...)> in the djvused man page. Returns zero if this information is not specified. */ DDJVUAPI const char * ddjvu_anno_get_horizalign(miniexp_t annotations); /* ddjvu_anno_get_vertalign -- Parse the annotations and extracts how the page image should be aligned vertically. See <(align ...)> in the djvused man page. Returns zero if this information is not specified. */ DDJVUAPI const char * ddjvu_anno_get_vertalign(miniexp_t annotations); /* ddjvu_anno_get_hyperlinks -- Parse the annotations and returns a zero terminated array of <(maparea ...)> s-expressions. The caller should free this array with function <free>. These s-expressions remain allocated as long as the annotations remain allocated. See also <(maparea ...)> in the djvused man page. */ DDJVUAPI miniexp_t * ddjvu_anno_get_hyperlinks(miniexp_t annotations); /* ddjvu_anno_get_metadata_keys -- Parse the annotations and returns a zero terminated array of key symbols for the page metadata. The caller should free this array with function <free>. See also <(metadata ...)> in the djvused man page. */ DDJVUAPI miniexp_t * ddjvu_anno_get_metadata_keys(miniexp_t annotations); /* ddjvu_anno_get_metadata -- Parse the annotations and returns the metadata string corresponding to the metadata key symbol <key>. The string remains allocated as long as the annotations s-expression remain allocated. Returns zero if no such key is present. */ DDJVUAPI const char * ddjvu_anno_get_metadata(miniexp_t annotations, miniexp_t key); /* ddjvu_anno_get_xmp -- Parse the annotations and returns the xmp metadata string. The string remains allocated as long as the annotations s-expression remain allocated. Returns zero if no such key is present. */ DDJVUAPI const char * ddjvu_anno_get_xmp(miniexp_t annotations); /* -------------------------------------------------- */ /* DJVU_MESSAGE_T */ /* -------------------------------------------------- */ /* We can now define the djvu_message_t union */ union ddjvu_message_s { struct ddjvu_message_any_s m_any; struct ddjvu_message_error_s m_error; struct ddjvu_message_info_s m_info; struct ddjvu_message_newstream_s m_newstream; struct ddjvu_message_docinfo_s m_docinfo; struct ddjvu_message_pageinfo_s m_pageinfo; struct ddjvu_message_chunk_s m_chunk; struct ddjvu_message_relayout_s m_relayout; struct ddjvu_message_redisplay_s m_redisplay; struct ddjvu_message_thumbnail_s m_thumbnail; struct ddjvu_message_progress_s m_progress; }; /* -------------------------------------------------- */ /* BACKDOORS */ /* -------------------------------------------------- */ #ifdef __cplusplus } // extern "C" #endif /* ddjvu_get_DjVuImage --- ddjvu_get_DjVuDocument --- These functions provide an access to the libdjvu objects associated with the ddjvuapi objects. These backdoors can be useful for advanced manipulations. These two functions are declared in C++ when file <"ddjvuapi.h"> is included after the libdjvu header files <"DjVuImage.h"> and <"DjVuDocument.h">. */ #ifdef __cplusplus # ifndef NOT_USING_DJVU_NAMESPACE # ifdef _DJVUIMAGE_H DDJVUAPI GP<DjVuImage> ddjvu_get_DjVuImage(ddjvu_page_t *page); # endif # ifdef _DJVUDOCUMENT_H DDJVUAPI GP<DjVuDocument> ddjvu_get_DjVuDocument(ddjvu_document_t *document); # endif # endif #endif #endif /* DDJVUAPI_H */