//C- -*- C++ -*- //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, Version 2. 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 //C- distributed by Lizardtech Software. On July 19th 2002, Lizardtech //C- Software authorized us to replace the original DjVu(r) Reference //C- Library notice by the following text (see doc/lizard2002.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, Version 2. 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- +------------------------------------------------------------------ // // $Id: DjVuImage.h,v 1.9 2005/04/27 16:34:13 leonb Exp $ // $Name: release_3_5_15 $ #ifndef _DJVUIMAGE_H #define _DJVUIMAGE_H #ifdef HAVE_CONFIG_H #include "config.h" #endif #if NEED_GNUG_PRAGMAS # pragma interface #endif /** @name DjVuImage.h Files #"DjVuImage.h"# and #"DjVuImage.cpp"# implement \Ref{DjVuImage} class produced as a result of decoding of DjVu files. In the previous version of the library both the rendering {\bf and} decoding have been handled by \Ref{DjVuImage}. This is no longer true. Now the \Ref{DjVuDocument} and \Ref{DjVuFile} classes handle decoding of both single page and multi page documents. For compatibility reasons though, we still support old-style decoding interface through the \Ref{DjVuImage} class for single page documents {\em only}. As before, the display programs can call the decoding function from a separate thread. The user interface thread may call the rendering functions at any time. Rendering will be performed using the most recent data generated by the decoding thread. This multithreaded capability enables progressive display of remote images. {\bf Creating DjVu images} --- Class \Ref{DjVuImage} does not provide a direct way to create a DjVu image. The recommended procedure consists of directly writing the required chunks into an \Ref{IFFByteStream} as demonstrated in program \Ref{djvumake}. Dealing with too many encoding issues (such as chunk ordering and encoding quality) would indeed make the decoder unnecessarily complex. {\bf ToDo: Layered structure} --- Class #DjVuImage# currently contains an unstructured collection of smart pointers to various data structures. Although it simplifies the rendering routines, this choice does not reflect the layered structure of DjVu images and does not leave much room for evolution. We should be able to do better. @memo Decoding DjVu and IW44 images. @author L\'eon Bottou - initial implementation Andrei Erofeev - multipage support @version #$Id: DjVuImage.h,v 1.9 2005/04/27 16:34:13 leonb Exp $# */ //@{ #include "DjVuFile.h" #include "DjVuAnno.h" #include "GRect.h" #ifdef HAVE_NAMESPACES namespace DJVU { # ifdef NOT_DEFINED // Just to fool emacs c++ mode } #endif #endif /* Obsolete class included for backward compatibility. */ class DjVuInterface { public: virtual ~DjVuInterface(); virtual void notify_chunk(const char *chkid, const char *msg) = 0; virtual void notify_relayout(void) = 0; virtual void notify_redisplay(void) = 0; }; /** Main DjVu Image data structure. This class defines the internal representation of a DjVu image. This representation consists of a few pointers referencing the various components of the DjVu image. These components are created and populated by the decoding function. The rendering functions then can use the available components to compute a pixel representation of the desired segment of the DjVu image. */ class DjVuImage : public DjVuPort { protected: DjVuImage(void); public: enum { NOINFO, NOTEXT=1, NOMAP=4, NOMETA=8 }; // CONSTRUCTION /** @name Construction. */ //@{ /** Creates an empty DjVu image. After the image has been constructed, it may be connected to an existing \Ref{DjVuFile} or left as is. In the former case #DjVuImage# will look for its decoded components (like #Sjbz# or #BG44#) by decending the hierarchy of \Ref{DjVuFile}s starting from the one passed to \Ref{connect}(). In the latter case you can use \Ref{decode}() function to decode {\bf single-page} DjVu documents in the old-style way. */ static GP create(void) {return new DjVuImage();} /** Connects this #DjVuImage# to the passed \Ref{DjVuFile}. The #DjVuImage# will use this \Ref{DjVuFile} to retrieve components necessary for decoding. It will also connect itself to \Ref{DjVuFile} using the communication mechanism provided by \Ref{DjVuPort} and \Ref{DjVuPortcaster}. This will allow it to receive and relay messages and requests generated by the passed \Ref{DjVuFile} and any file included into it. */ void connect(const GP & file); /** This combines the above two steps for simplier code operations. */ static GP create(const GP &file) { const GP retval=create(); retval->connect(file); return retval; } //@} // COMPONENTS /** @name Components. */ //@{ /** Returns a pointer to a DjVu information component. This function returns a null pointer until the decoder actually processes an #"INFO"# chunk. */ GP get_info() const; /** Returns a pointer to the IW44 encoded background component of a DjVu image. This function returns a null pointer until the decoder actually processes an #"BG44"# chunk. */ GP get_bg44() const; /** Returns a pointer to the raw background component of a DjVu image. The background component is used for JPEG encoded backgrounds. This function returns a null pointer until the decoder actually processes an #"BGjp"# chunk. */ GP get_bgpm() const; /** Returns a pointer to the mask of the foreground component of a DjVu image. The mask of the foreground component is always a JB2 image in this implementation. This function returns a null pointer until the decoder actually processes an #"Sjbz"# chunk. */ GP get_fgjb() const; /** Returns a pointer to the colors of the foreground component of a DjVu image. The mask of the foreground component is always a small pixmap in this implementation. This function returns a null pointer until the decoder actually processes an #"FG44"# chunk. */ GP get_fgpm() const; /** Returns a pointer to a palette object containing colors for the foreground components of a DjVu image. These colors are only pertinent with respect to the JB2Image. */ GP get_fgbc() const; /** Returns a pointer to a ByteStream containing all the annotation chunks collected so far for this image. Individual chunks can be retrieved using \Ref{IFFByteStream}. Returns NULL if no chunks have been collected yet. */ GP get_anno() const; /** Returns a pointer to a ByteStream containing all the hidden text. Returns NULL if no chunks have been collected yet. */ GP get_text() const; /** Returns a pointer to a ByteStream containing all the metadata. Returns NULL if no chunks have been collected yet. */ GP get_meta() const; //@} // NEW STYLE DECODING /** @name New style decoding. */ //@{ /** The decoder is now started when the image is created by function \Ref{DjVuDocument::get_page} in \Ref{DjVuDocument}. This function waits until the decoding thread terminates and returns TRUE if the image has been successfully decoded. */ bool wait_for_complete_decode(void); //@} // OLD STYLE DECODING /** @name Old style decoding (backward compatibility). */ //@{ /** This function is here for backward compatibility. Now, with the introduction of multipage DjVu documents, the decoding is handled by \Ref{DjVuFile} and \Ref{DjVuDocument} classes. For single page documents though, we still have this wrapper. */ void decode(ByteStream & str, DjVuInterface *notifier=0); //@} // UTILITIES /** @name Utilities */ //@{ /** Returns the width of the DjVu image. This function just extracts this information from the DjVu information component. It returns zero if such a component is not yet available. This gives rotated width if there is any rotation of image. If you need real width, use #get_real_width()#.*/ int get_width() const; /** Returns the height of the DjVu image. This function just extracts this information from the DjVu information component. It returns zero if such a component is not yet available. This gives rotated height if there is any rotation of image. If you need real width, use #get_real_height()#.*/ int get_height() const; /** Returns the width of the DjVu image. This function just extracts this information from the DjVu information component. It returns zero if such a component is not yet available.*/ int get_real_width() const; /** Returns the height of the DjVu image. This function just extracts this information from the DjVu information component. It returns zero if such a component is not yet available.*/ int get_real_height() const; /** Returns the format version the DjVu data. This function just extracts this information from the DjVu information component. It returns zero if such a component is not yet available. This version number should be compared with the \Ref{DjVu version constants}. */ int get_version() const; /** Returns the resolution of the DjVu image. This information is given in pixels per 2.54 cm. Display programs can use this information to determine the natural magnification to use for rendering a DjVu image. */ int get_dpi() const; /** Same as \Ref{get_dpi}() but instead of precise value returns the closest "standard" one: 25, 50, 75, 100, 150, 300, 600. If dpi is greater than 700, it's returned as is. */ int get_rounded_dpi() const; /** Returns the gamma coefficient of the display for which the image was designed. The rendering functions can use this information in order to perform color correction for the intended display device. */ double get_gamma() const; /** Returns a MIME type string describing the DjVu data. This information is auto-sensed by the decoder. The MIME type can be #"image/djvu"# or #"image/iw44"# depending on the data stream. */ GUTF8String get_mimetype() const; /** Returns a short string describing the DjVu image. Example: #"2500x3223 in 23.1 Kb"#. */ GUTF8String get_short_description() const; /** Returns a verbose description of the DjVu image. This description lists all the chunks with their size and a brief comment, as shown in the following example. \begin{verbatim} DJVU Image (2325x3156) version 17: 0.0 Kb 'INFO' Page information. 17.3 Kb 'Sjbz' JB2 foreground mask (2325x3156) 2.5 Kb 'BG44' IW44 background (775x1052) 1.0 Kb 'FG44' IW44 foreground colors (194x263) 3.0 Kb 'BG44' IW44 background (part 2). 0.9 Kb 'BG44' IW44 background (part 3). 7.1 Kb 'BG44' IW44 background (part 4). Compression ratio: 676 (31.8 Kb) \end{verbatim} */ GUTF8String get_long_description() const; /** Returns pointer to \Ref{DjVuFile} which contains this image in compressed form. */ GP get_djvu_file(void) const; /// Write out a DjVuXML object tag and map tag. void writeXML(ByteStream &str_out,const GURL &doc_url, const int flags=0) const; /// Write out a DjVuXML object tag and map tag. void writeXML(ByteStream &str_out) const; /// Get a DjVuXML object tag and map tag. GUTF8String get_XML(const GURL &doc_url, const int flags=0) const; /// Get a DjVuXML object tag and map tag. GUTF8String get_XML(void) const; //@} // CHECKING /** @name Checking for legal DjVu files. */ //@{ /** This function returns true if this object contains a well formed {\em Photo DjVu Image}. Calling function #get_pixmap# on a well formed photo image should always return a non zero value. Note that function #get_pixmap# works as soon as sufficient information is present, regardless of the fact that the image follows the rules or not. */ int is_legal_photo() const; /** This function returns true if this object contains a well formed {\em Bilevel DjVu Image}. Calling function #get_bitmap# on a well formed bilevel image should always return a non zero value. Note that function #get_bitmap# works as soon as a foreground mask component is present, regardless of the fact that the image follows the rules or not. */ int is_legal_bilevel() const; /** This function returns true if this object contains a well formed {\em Compound DjVu Image}. Calling function #get_bitmap# or #get_pixmap# on a well formed compound DjVu image should always return a non zero value. Note that functions #get_bitmap# or #get_pixmap# works as soon as sufficient information is present, regardless of the fact that the image follows the rules or not. */ int is_legal_compound() const; //@} // RENDERING /** @name Rendering. All these functions take two rectangles as argument. Conceptually, these function first render the whole image into a rectangular area defined by rectangle #all#. The relation between this rectangle and the image size define the appropriate scaling. The rendering function then extract the subrectangle #rect# and return the corresponding pixels as a #GPixmap# or #GBitmap# object. The #all# and #rect# should take the any rotation in to effect, The actual implementation performs these two operation simultaneously for obvious efficiency reasons. The best rendering speed is achieved by making sure that the size of rectangle #all# and the size of the DjVu image are related by an integer ratio. */ //@{ /** Renders the image and returns a color pixel image. Rectangles #rect# and #all# are used as explained above. Color correction is performed according to argument #gamma#, which represents the gamma coefficient of the display device on which the pixmap will be rendered. The default value, zero, means that no color correction should be performed. This function returns a null pointer if there is not enough information in the DjVu image to properly render the desired image. */ GP get_pixmap(const GRect &rect, const GRect &all, double gamma=0) const; /** Renders the mask of the foreground layer of the DjVu image. This functions is a wrapper for \Ref{JB2Image::get_bitmap}. Argument #align# specified the alignment of the rows of the returned images. Setting #align# to #4#, for instance, will adjust the bitmap border in order to make sure that each row of the returned image starts on a word (four byte) boundary. This function returns a null pointer if there is not enough information in the DjVu image to properly render the desired image. */ GP get_bitmap(const GRect &rect, const GRect &all, int align = 1) const; /** Renders the background layer of the DjVu image. Rectangles #rect# and #all# are used as explained above. Color correction is performed according to argument #gamma#, which represents the gamma coefficient of the display device on which the pixmap will be rendered. The default value, zero, means that no color correction should be performed. This function returns a null pointer if there is not enough information in the DjVu image to properly render the desired image. */ GP get_bg_pixmap(const GRect &rect, const GRect &all, double gamma=0) const; /** Renders the foreground layer of the DjVu image. Rectangles #rect# and #all# are used as explained above. Color correction is performed according to argument #gamma#, which represents the gamma coefficient of the display device on which the pixmap will be rendered. The default value, zero, means that no color correction should be performed. This function returns a null pointer if there is not enough information in the DjVu image to properly render the desired image. */ GP get_fg_pixmap(const GRect &rect, const GRect &all, double gamma=0) const; /** set the rotation count(angle) in counter clock wise for the image values (0,1,2,3) correspond to (0,90,180,270) degree rotation*/ void set_rotate(int count=0); /** returns the rotation count*/ int get_rotate() const; /** returns decoded annotations in DjVuAnno object in which all hyperlinks and hilighted areas are rotated as per rotation setting*/ GP get_decoded_anno(); /** maps the given #rect# from rotated co-ordinates to unrotated document co-ordinates*/ void map(GRect &rect) const; /** unmaps the given #rect# from unrotated document co-ordinates to rotated co-ordinates*/ void unmap(GRect &rect) const; /** maps the given #x#, #y# from rotated co-ordinates to unrotated document co-ordinates*/ void map(int &x, int &y) const; /** unmaps the given #x#, #y# from unrotated document co-ordinates to rotated co-ordinates*/ void unmap(int &x, int &y) const; //@} // Inherited from DjVuPort. virtual void notify_chunk_done(const DjVuPort *, const GUTF8String &name); // SUPERSEDED GP get_pixmap(const GRect &rect, int subs=1, double gamma=0) const; GP get_bitmap(const GRect &rect, int subs=1, int align = 1) const; GP get_bg_pixmap(const GRect &rect, int subs=1, double gamma=0) const; GP get_fg_pixmap(const GRect &rect, int subs=1, double gamma=0) const; private: GP file; int rotate_count; bool relayout_sent; // HELPERS int stencil(GPixmap *pm, const GRect &rect, int subs, double gcorr) const; GP get_info(const GP & file) const; GP get_bg44(const GP & file) const; GP get_bgpm(const GP & file) const; GP get_fgjb(const GP & file) const; GP get_fgpm(const GP & file) const; GP get_fgbc(const GP & file) const; void init_rotate(const DjVuInfo &info); }; inline GP DjVuImage::get_djvu_file(void) const { return file; } //@} // ----- THE END #ifdef HAVE_NAMESPACES } # ifndef NOT_USING_DJVU_NAMESPACE using namespace DJVU; # endif #endif #endif