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diff --git a/kviewshell/plugins/djvu/libdjvu/GPixmap.h b/kviewshell/plugins/djvu/libdjvu/GPixmap.h new file mode 100644 index 00000000..32d51c7e --- /dev/null +++ b/kviewshell/plugins/djvu/libdjvu/GPixmap.h @@ -0,0 +1,531 @@ +//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: GPixmap.h,v 1.8 2003/11/07 22:08:21 leonb Exp $ +// $Name: release_3_5_15 $ + +#ifndef _GPIXMAP_H_ +#define _GPIXMAP_H_ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif +#if NEED_GNUG_PRAGMAS +# pragma interface +#endif + +/** @name GPixmap.h + + Files #"GPixmap.h"# and #"GPixmap.cpp"# implement class \Ref{GPixmap}. + Instances of this class represent color images. Each RGB pixel is + represented by structure \Ref{GPixel}. The ``bottom left'' coordinate system + is used consistently in the DjVu library. Line zero of a GPixmap is the + bottom line in the color image. Pixels are organized from left to right + within each line. + + {\bf ToDo} --- More sophisticated color correction schemes. + + @memo + Generic support for color images. + @author + L\'eon Bottou <leonb@research.att.com> + @version + #$Id: GPixmap.h,v 1.8 2003/11/07 22:08:21 leonb Exp $# */ +//@{ + + +#include "GSmartPointer.h" + +#ifdef HAVE_NAMESPACES +namespace DJVU { +# ifdef NOT_DEFINED // Just to fool emacs c++ mode +} +#endif +#endif + + +class GBitmap; +class GRect; +class ByteStream; + + +/** Color pixel as a RGB triple. + The colors are represented using three bytes named #r#, #g# and #b#. The + value of these bytes represent additive amounts of light. Color white is + represented by setting all three bytes to #255#. Color black is + represented by setting all three bytes to #0#. This convention should not + be confused with the convention adopted for class \Ref{GBitmap} where the + pixel values represent an ink level. */ + +struct GPixel +{ + /** Blue component. */ + unsigned char b; + /** Green component. */ + unsigned char g; + /** Red component. */ + unsigned char r; + /** Returns true iff colors are identical. */ + friend int operator==(const GPixel & p1, const GPixel & p2); + /** Returns true iff colors are different. */ + friend int operator!=(const GPixel & p1, const GPixel & p2); + /** Returns a hash code for the color. */ + friend unsigned int hash(const GPixel &p); + /** @name Predefined colors. */ + //@{ + /// GPixel::WHITE is initialized to #rgb:255/255/255#. + static const GPixel WHITE; + /// GPixel::BLACK is initialized to #rgb:0/0/0#. + static const GPixel BLACK; + /// GPixel::BLUE is initialized to #rgb:0/0/255#. + static const GPixel BLUE; + /// GPixel::GREEN is initialized to #rgb:0/255/0#. + static const GPixel GREEN; + /// GPixel::RED is initialized to #rgb:255/0/0#. + static const GPixel RED; + //@} +}; + + +/** RGB Color images. + Instances of class #GPixmap# represent color images as a two dimensional + array of pixels \Ref{GPixel}. The bracket operator returns a pointer to + the pixels composing one line of the image. This pointer can be used as + an array to read or write the pixels of this particular line. Following + the general convention of the DjVu Reference Library, line zero is always + the bottom line of the image. + */ + +class GPixmap : public GPEnabled +{ +protected: + GPixmap(void); + GPixmap(int nrows, int ncolumns, const GPixel *filler=0); + GPixmap(const GBitmap &ref); + GPixmap(const GBitmap &ref, const GRect &rect); + GPixmap(const GPixmap &ref); + GPixmap(const GPixmap &ref, const GRect &rect); + GPixmap(ByteStream &ref); + +public: + /// Virtual destructor. + virtual ~GPixmap(); + + void destroy(void); + /** @name Construction. */ + //@{ + /** Creates an empty GBitmap object. The returned GPixmap has zero rows + and zero columns. Use function \Ref{init} to change the size of the + image. */ + static GP<GPixmap> create(void) {return new GPixmap();} + + /** Creates a GPixmap with #nrows# rows and #ncolumns# columns. When the + optional argument #filler# is specified, all pixels are initialized + with the corresponding color. */ + static GP<GPixmap> create( + const int nrows, const int ncolumns, const GPixel *filler=0) + { return new GPixmap(nrows,ncolumns,filler); } + + /** Creates a GPixmap by copying the gray level image #ref#. + The constructed GPixmap has the same size as #ref#. The pixels + are initialized with shades of grays copied from #ref#. */ + static GP<GPixmap> create(const GBitmap &ref) + { return new GPixmap(ref); } + + /** Creates a GPixmap by copying the rectangle #rect# of the gray level + image #ref#. The constructed GPixmap has the same size as rectangle + #rect#. The pixels are initialized with shades of grays converted from + the ink levels represented in #ref#. This conversion depends on the + number of gray levels in #ref#. */ + static GP<GPixmap> create(const GBitmap &ref, const GRect &rect) + { return new GPixmap(ref,rect); } + + /** Copy constructors. Creates a GPixmap by replicating the size and the + contents of GPixmap #ref#. */ + static GP<GPixmap> create(const GPixmap &ref) + { return new GPixmap(ref); } + + /** Creates a GPixmap by copying the rectangle #rect# of the color image #ref#. + The constructed GPixmap has the same size as rectangle #rect#. + The pixels are initialized with colors copied from #ref#. */ + static GP<GPixmap> create(const GPixmap &ref, const GRect &rect) + { return new GPixmap(ref,rect); } + + /** Creates a GPixmap by reading PPM data from ByteStream #ref#. + See \Ref{PNM and RLE file formats} for more information. */ + static GP<GPixmap> create(ByteStream &ref) + { return new GPixmap(ref); } + + //@} + + /** @name Initialization. */ + //@{ + /** Resets the GPixmap to #nrows# rows and #ncolumns# columns. When the + optional argument #filler# is specified, all pixels are initialized with + the corresponding color. The previous content of the GPixmap is discarded. */ + void init(int nrows, int ncolumns, const GPixel *filler=0); + /** Resets the GPixmap by copying the size and the contents of the color + image #ref#. The previous content of the GPixmap is discarded. */ + void init(const GPixmap &ref); + /** Resets the GPixmap by copying the rectangle #rect# of the color image #ref#. + The previous content of the GPixmap is discarded. */ + void init(const GPixmap &ref, const GRect &rect); + /** Resets the GPixmap by copying the size and the contents of the gray + level image #ref#. The optional argument #ramp# is an array of 256 + pixel values used for mapping the gray levels to color values. + Setting #ramp# to zero selects a linear ramp of shades of gray. */ + void init(const GBitmap &ref, const GPixel *ramp=0); + /** Resets the GPixmap by copying the rectangle #rect# of the gray level + image #ref#. The optional argument #ramp# is an array of 256 pixel + values used for mapping the gray levels to color values. Setting #ramp# + to zero selects a linear ramp computed according to the maximal number + of gray levels in #ref#. */ + void init(const GBitmap &ref, const GRect &rect, const GPixel *ramp=0); + /** Resets the GPixmap by reading PPM data from ByteStream #ref#. See + \Ref{PNM and RLE file formats} for more information. */ + void init(ByteStream &ref); + /** Resets the GPixmap by copying the gray level image #ref#. The pixels + are initialized with shades of grays copied from #ref#. */ + GPixmap& operator=(const GBitmap &ref); + /** Copy operator. Resets the GPixmap by copying the size and the contents + of the color image #ref#. The previous content of the GPixmap is + discarded. */ + GPixmap& operator=(const GPixmap &ref); + //@} + + /** @name Accessing pixels. */ + //@{ + /** Returns the number of rows (the image height). */ + unsigned int rows() const; + /** Returns the number of columns (the image width). */ + unsigned int columns() const; + /** Returns a constant pointer to the first GPixel in row #row#. This + pointer can be used as an array to read the row elements. */ + const GPixel * operator[] (int row) const; + /** Returns a pointer to the first GPixel in row #row#. This pointer can be + used as an array to read or write the row elements. */ + GPixel * operator[] (int row); + /** Returns the length (in pixels) of a row in memory. This number is equal + to the difference between pointers to pixels located in the same column + in consecutive rows. This difference may be larger than the number of + columns in the image. */ + unsigned int rowsize() const; + //@} + + /** @name Resampling images. */ + //@{ + /** Resets this GPixmap with a subsampled segment of color image #src#. + This function conceptually rescales image #src# by a factor #1:factor#, + and copies rectangle #rect# of the subsampled image into the current GPixmap. + The full subsampled image is copied if #rect# is a null pointer. + Both operations are however performed together for efficiency reasons. + Subsampling works by averaging the colors of the source pixels located + in small squares of size #factor# times #factor#. */ + void downsample(const GPixmap *src, int factor, const GRect *rect=0); + /** Resets this GPixmap with a oversampled segment of color image #src#. + This function conceptually rescales image #src# by a factor #factor:1#, + and copies rectangle #rect# of the oversampled image into the current + GPixmap. The full oversampled image is copied if #rect# is a null + pointer. Both operations are however performed together for efficiency + reasons. Oversampling works by replicating the color of the source + pixels into squares of size #factor# times #factor#. */ + void upsample(const GPixmap *src, int factor, const GRect *rect=0); + /** Resets this GPixmap with a rescaled segment of #src# (zoom 75%). This + function conceptually rescales image #src# by a factor #3:4#, and copies + rectangle #rect# of the rescaled image into the current GPixmap. The + full rescaled image is copied if #rect# is a null pointer. Both + operations are however performed together for efficiency reasons. This + function has been superseded by class \Ref{GPixmapScaler}. */ + void downsample43(const GPixmap *src, const GRect *rect=0); + /** Resets this GPixmap with a rescaled segment of #src# (zoom 150%). This + function conceptually rescales image #src# by a factor #3:2# and copies + rectangle #rect# of the rescaled image into the current GPixmap. The + full rescaled image is copied if #rect# is a null pointer. Both + operations are however performed together for efficiency reasons. This + function has been superseded by class \Ref{GPixmapScaler}. */ + void upsample23(const GPixmap *src, const GRect *rect=0); + //@} + + /** @name Blitting and applying stencils. + These function is essential for rendering DjVu images. The elementary + functions are \Ref{attenuate} and \Ref{blit}. The combined functions + \Ref{blend} and \Ref{stencil} should be viewed as optimizations. */ + //@{ + /** Attenuates the color image in preparation for a blit. + Bitmap #bm# is positionned at location #x#,#y# over this color image. + The matching color image pixels are then multiplied by #1.0-Alpha# where + #Alpha# denotes the gray value, in range #[0,1]#, represented by the + corresponding pixel of bitmap #bm#. */ + void attenuate(const GBitmap *bm, int x, int y); + /** Blits solid color #color# through transparency mask #bm#. + Bitmap #bm# is positionned at location #x#,#y# over this color image. + The matching color image pixels are then modified by adding color + #color# multiplied by #Alpha#, where #Alpha# denotes the gray value, in + range #[0,1]#, represented by the corresponding pixel of bitmap #bm#. */ + void blit(const GBitmap *bm, int x, int y, const GPixel *color); + /** Blits pixmap #color# through transparency mask #bm#. + Bitmap #bm# is positionned at location #x#,#y# over this color image. + The matching color image pixels are then modified by adding the + corresponding pixel color in pixmap #color#, multiplied by #Alpha#, + where #Alpha# denotes the gray value, in range #[0,1]#, represented by + the corresponding pixel of bitmap #bm#. */ + void blit(const GBitmap *bm, int x, int y, const GPixmap *color); + /** Performs alpha blending. This function is similar to first calling + \Ref{attenuate} with alpha map #bm# and then calling \Ref{blit} with + alpha map #bm# and color map #color#. Both operations are performed + together for efficiency reasons. */ + void blend(const GBitmap *bm, int x, int y, const GPixmap *color); + /** Resample color pixmap and performs color corrected alpha blending. This + function conceptually computes an intermediate color image by first + upsampling the GPixmap #pm# by a factor #pms:1# (see \Ref{upsample}), + extracting the sub-image designated by rectangle #pmr# and applying + color correction #corr# (see \Ref{color_correct}). This intermediate + color image is then blended into this pixel map according to the alpha + map #bm# (see \Ref{blend}). */ + void stencil(const GBitmap *bm, + const GPixmap *pm, int pms, + const GRect *pmr, double corr=1.0); + //@} + + /** @name Manipulating colors. */ + //@{ + /** Dithers the image to 216 colors. This function applies an ordered + dithering algorithm to reduce the image to 216 predefined colors. These + predefined colors are located on a color cube of 6x6x6 colors: the color + RGB coordinates can only take the following values: #0#, #51#, #102#, + #163#, #214# or #255#. This is useful for displaying images on a device + supporting a maximum of 256 colors. Arguments #xmin# and #ymin# control + the position of the dithering grids. This is useful for dithering tiled + images. Arguments #xmin# and #ymin# must be the position of the bottom + left corner of the tile contained in this GPixmap. Properly setting + these arguments eliminates dithering artifacts on the tile + boundaries. */ + void ordered_666_dither(int xmin=0, int ymin=0); + /** Dithers the image to 32768 colors. This function applies an ordered + dithering algorithm to reduce the image to 32768 predefined colors. + These predefined colors are located on a color cube of 32x32x32 colors: + the color RGB coordinates can only take values in which the three least + significant bits are set to #1#. This is useful for displaying images + with less than 24 bits per pixel. Arguments #xmin# and #ymin# control + the position of the dithering grids. This is useful for dithering tiled + images. Arguments #xmin# and #ymin# must be the position of the bottom + left corner of the tile contained in this GPixmap. Properly setting + these arguments eliminates dithering artifacts on the tile + boundaries. */ + void ordered_32k_dither(int xmin=0, int ymin=0); + /** Applies a luminance gamma correction factor of #corr#. Values greater than + #1.0# make the image brighter. Values smaller than #1.0# make the image + darker. The documentation of program \Ref{ppmcoco} explains how to + properly use this function. */ + void color_correct(double corr); + /** Applies a luminance gamma correction to an array of pixels. + This function is {\em static} and does not modify this pixmap. */ + static void color_correct(double corr, GPixel *pixels, int npixels); + + //@} + + /** @name Miscellaneous. */ + //@{ + /** Returns the number of bytes allocated for this image. */ + inline unsigned int get_memory_usage() const; + /** Saves the image into ByteStream #bs# using the PPM format. + Argument #raw# selects the ``Raw PPM'' (1) or the ``Ascii PPM'' (0) format. + See \Ref{PNM and RLE file formats} for more information. */ + void save_ppm(ByteStream &bs, int raw=1) const; + //@} + + /** @name Stealing or borrowing the memory buffer (advanced). */ + //@{ + /** Steals the memory buffer of a GPixmap. This function returns the + address of the memory buffer allocated by this GPixmap object. The + offset of the first pixel in the bottom line is written into variable + #offset#. Other lines can be accessed using pointer arithmetic (see + \Ref{rowsize}). The GPixmap object no longer ``owns'' the buffer: you + must explicitly de-allocate the buffer using #operator delete []#. This + de-allocation should take place after the destruction or the + re-initialization of the GPixmap object. This function will return a + null pointer if the GPixmap object does not ``own'' the buffer in the + first place. */ + GPixel *take_data(size_t &offset); + /** Initializes this GPixmap by borrowing a memory segment. The GPixmap + then directly addresses the memory buffer #data# provided by the user. + This buffer must be large enough to hold #w*h# GPixels. The GPixmap + object does not ``own'' the buffer: you must explicitly de-allocate the + buffer using #operator delete []#. This de-allocation should take place + after the destruction or the re-initialization of the GPixmap object. */ + inline void borrow_data(GPixel &data, int w, int h); + /// Identical to the above, but GPixmap will do the delete []. + void donate_data(GPixel *data, int w, int h); + + /** Rotates pixmap by 90, 180 or 270 degrees anticlockwise + and returns a new pixmap, input pixmap is not changed. + count can be 1, 2, or 3 for 90, 180, 270 degree rotation. + It returns the same pixmap if not rotated. */ + GP<GPixmap> rotate(int count=0); + + //@} + + // Please ignore these two functions. Their only purpose is to allow + // DjVu viewer compile w/o errors. eaf. + // Is this still useful ?. lyb. + int get_grays(void) const { return 256; }; + void set_grays(int) {};\ + +protected: + // data + unsigned short nrows; + unsigned short ncolumns; + unsigned short nrowsize; + GPixel *pixels; + GPixel *pixels_data; + friend class DjVu_PixImage; +}; + +//@} + +// INLINE -------------------------- + + +inline int +operator==(const GPixel & p1, const GPixel & p2) +{ + return p1.r==p2.r && p1.g==p2.g && p1.b==p2.b; +} + +inline int +operator!=(const GPixel & p1, const GPixel & p2) +{ + return p1.r!=p2.r || p1.g!=p2.g || p1.b!=p2.b; +} + +inline unsigned int +hash(const GPixel &p) +{ + unsigned int x = (p.b<<16)|(p.g<<8)|(p.r); + return x ^ (p.b<<4) ^ (p.r<<12); +} + +inline unsigned int +GPixmap::rows() const +{ + return nrows; +} + +inline unsigned int +GPixmap::columns() const +{ + return ncolumns; +} + +inline unsigned int +GPixmap::rowsize() const +{ + return nrowsize; +} + +inline GPixel * +GPixmap::operator[](int row) +{ + if (row<0 || row>=nrows || !pixels) return 0; + return &pixels[row * nrowsize]; +} + +inline const GPixel * +GPixmap::operator[](int row) const +{ + if (row<0 || row>=nrows) return 0; + return &pixels[row * nrowsize]; +} + +inline GPixmap & +GPixmap::operator=(const GBitmap &ref) +{ + init(ref); + return *this; +} + +inline GPixmap & +GPixmap::operator=(const GPixmap &ref) +{ + init(ref); + return *this; +} + +inline void +GPixmap::borrow_data(GPixel &data, int w, int h) +{ + donate_data(&data,w,h); + pixels_data=0; +} + +////////////////////////////////////////////////// +// Memory usage +////////////////////////////////////////////////// + + +inline unsigned int +GPixmap::get_memory_usage() const +{ + return sizeof(GPixmap)+(nrows * ncolumns * sizeof(GPixel)); +} + +// --------------------------------- + +#ifdef HAVE_NAMESPACES +} +# ifndef NOT_USING_DJVU_NAMESPACE +using namespace DJVU; +# endif +#endif +#endif + + |