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diff --git a/kviewshell/plugins/djvu/libdjvu/DjVuPalette.h b/kviewshell/plugins/djvu/libdjvu/DjVuPalette.h new file mode 100644 index 00000000..7f9884f1 --- /dev/null +++ b/kviewshell/plugins/djvu/libdjvu/DjVuPalette.h @@ -0,0 +1,339 @@ +//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: DjVuPalette.h,v 1.9 2003/11/07 22:08:21 leonb Exp $ +// $Name: release_3_5_15 $ + +#ifndef _DJVUPALETTE_H_ +#define _DJVUPALETTE_H_ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif +#if NEED_GNUG_PRAGMAS +# pragma interface +#endif + + +#include "GContainer.h" +#include "GPixmap.h" +#include <string.h> + + +#ifdef HAVE_NAMESPACES +namespace DJVU { +# ifdef NOT_DEFINED // Just to fool emacs c++ mode +} +#endif +#endif + + +/** @name DjVuPalette.h + Files #"DjVuPalette.h"# and #"DjVuPalette.cpp"# implement a single class + \Ref{DjVuPalette} which provides facilities for computing optimal color + palettes, coding color palettes, and coding sequences of color indices. + @memo + DjVuPalette header file + @version + #$Id: DjVuPalette.h,v 1.9 2003/11/07 22:08:21 leonb Exp $# + @author: + L\'eon Bottou <leonb@research.att.com> */ +//@{ + + +/** Computing and coding color palettes and index arrays. + This class provides facilities for computing optimal color palettes, + coding color palettes, and coding sequences of color indices. + + {\bf Creating a color palette} -- The recipe for creating a color palette + consists in (a) creating a DjVuPalette object, (b) constructing a color + histogram using \Ref{histogram_add}, and (c) calling function + \Ref{compute_palette}. + + {\bf Accessing the color palette} -- Conversion between colors and color + palette indices is easily achieved with \Ref{color_to_index} and + \Ref{index_to_color}. There are also functions for computing a palette + and quantizing a complete pixmap. + + {\bf Sequences of color indices} -- The DjVuPalette object also contains + an array \Ref{colordata} optionally containing a sequence of color + indices. This array will be encoded and decoded by functions \Ref{encode} + and \Ref{decode}. This feature simplifies the implementation of the ``one + color per symbol'' model in DjVu. + + {\bf Coding color palettes and color indices} -- Two functions + \Ref{encode} and \Ref{decode} are provided for coding the color palette + and the array of color indices when appropriate. */ +#ifdef _WIN32_WCE_EMULATION // Work around odd behavior under WCE Emulation +#define CALLINGCONVENTION __cdecl +#else +#define CALLINGCONVENTION /* */ +#endif + +class DjVuPalette : public GPEnabled +{ +protected: + DjVuPalette(void); +public: + /// Generic creator + static GP<DjVuPalette> create(void) {return new DjVuPalette();} + + /// Non-virtual destructor + ~DjVuPalette(); + // COPY + DjVuPalette(const DjVuPalette &ref); + DjVuPalette& operator=(const DjVuPalette &ref); + // PALETTE COMPUTATION + /** Resets the color histogram to zero. */ + void histogram_clear(); + /** Adds the color specified by #p# to the histogram. + Argument #weight# represent the number of pixels with this color. */ + void histogram_add(const GPixel &p, int weight); + /** Adds the color specified by the triple #bgr# to the histogram. + Argument #weight# represent the number of pixels with this color. */ + void histogram_add(const unsigned char *bgr, int weight); + /** Adds the color specified by the weighted triple #bgr# to the histogram. + Argument #weight# represent the number of pixels with this color. This + function will compute the actual color by dividing the elements of the + #bgr# array by #weight# and then use the unnormalized values to compute + the average color per bucket. This is all a way to avoid excessive loss + of accuracy. */ + void histogram_norm_and_add(const int *bgr, int weight); + /** Computes an optimal palette for representing an image where colors + appear according to the histogram. Argument #maxcolors# is the maximum + number of colors allowed in the palette (up to 1024). Argument + #minboxsize# controls the minimal size of the color cube area affected + to a color palette entry. Returns the index of the dominant color. */ + int compute_palette(int maxcolors, int minboxsize=0); + /** Computes the optimal palette for pixmap #pm#. This function builds the + histogram for pixmap #pm# and computes the optimal palette using + \Ref{compute_palette}. */ + int compute_pixmap_palette(const GPixmap &pm, int ncolors, int minboxsize=0); + // CONVERSION + /** Returns the number of colors in the palette. */ + int size() const; + /** Returns the best palette index for representing color #p#. */ + int color_to_index(const GPixel &p); + /** Returns the best palette index for representing color #bgr#. */ + int color_to_index(const unsigned char *bgr); + /** Overwrites #p# with the color located at position #index# in the palette. */ + void index_to_color(int index, GPixel &p) const; + /** Overwrites #rgb[0..3]# with the color located at + position #index# in the palette. */ + void index_to_color(int index, unsigned char *bgr) const; + /** Quantizes pixmap #pm#. All pixels are replaced by their closest + approximation available in the palette. */ + void quantize(GPixmap &pm); + /** Calls \Ref{compute_pixmap_palette} and \Ref{quantize}. */ + int compute_palette_and_quantize(GPixmap &pm, int maxcolors, int minboxsize=0); + // COLOR CORRECTION + /** Applies a luminance gamma correction factor of #corr# to the palette + entries. 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); + // COLOR INDEX DATA + /** Contains an optional sequence of color indices. + Function \Ref{encode} and \Ref{decode} also encode and decode this + sequence when such a sequence is provided. */ + GTArray<short> colordata; + /** Returns colors from the color index sequence. Pixel #out# is + overwritten with the color corresponding to the #nth# element of the + color sequence \Ref{colordata}. */ + void get_color(int nth, GPixel &out) const; + // CODING + /** Writes the palette colors. This function writes each palette color as a + RGB triple into bytestream #bs#. */ + void encode_rgb_entries(ByteStream &bs) const; + /** Reads palette colors. This function initializes the palette colors by + reading #palettesize# RGB triples from bytestream #bs#. */ + void decode_rgb_entries(ByteStream &bs, const int palettesize); + /** Encodes the palette and the color index sequence. This function encodes + the a version byte, the palette size, the palette colors and the color + index sequence into bytestream #bs#. Note that the color histogram is + never saved. */ + void encode(GP<ByteStream> bs) const; + /** Initializes the object by reading data from bytestream #bs#. This + function reads a version byte, the palette size, the palette and the + color index sequence from bytestream #bs#. Note that the color + histogram is never saved. */ + void decode(GP<ByteStream> bs); + +private: + // Histogram + int mask; + GMap<int,int> *hist; + // Quantization data + struct PColor { unsigned char p[4]; }; + GTArray<PColor> palette; + GMap<int,int> *pmap; + // Helpers + void allocate_hist(); + void allocate_pmap(); + static int CALLINGCONVENTION bcomp (const void*, const void*); + static int CALLINGCONVENTION gcomp (const void*, const void*); + static int CALLINGCONVENTION rcomp (const void*, const void*); + static int CALLINGCONVENTION lcomp (const void*, const void*); + int color_to_index_slow(const unsigned char *bgr); +private: // dummy functions + static void encode(ByteStream *); + static void decode(ByteStream *); +}; + + +//@} + +// ------------ INLINES + + +inline void +DjVuPalette::histogram_clear() +{ + delete hist; + hist = 0; + mask = 0; +} + +inline void +DjVuPalette::histogram_add(const unsigned char *bgr, int weight) +{ + if (weight > 0) + { + if (!hist || hist->size()>=0x4000) + allocate_hist(); + int key = (bgr[0]<<16)|(bgr[1]<<8)|(bgr[2])|(mask); + (*hist)[key] += weight; + } +} + +inline void +DjVuPalette::histogram_add(const GPixel &p, int weight) +{ + histogram_add(&p.b, weight); +} + +inline void +DjVuPalette::histogram_norm_and_add(const int *bgr, int weight) +{ + if (weight > 0) + { + int p0 = bgr[0]/weight; if (p0>255) p0=255; + int p1 = bgr[1]/weight; if (p1>255) p1=255; + int p2 = bgr[2]/weight; if (p2>255) p2=255; + if (!hist || hist->size()>=0x4000) + allocate_hist(); + int key = (p0<<16)|(p1<<8)|(p2)|(mask); + (*hist)[key] += weight; + } +} + +inline int +DjVuPalette::size() const +{ + return palette.size(); +} + +inline int +DjVuPalette::color_to_index(const unsigned char *bgr) +{ + if (! pmap) + allocate_pmap(); + int key = (bgr[0]<<16)|(bgr[1]<<8)|(bgr[2]); + GPosition p = pmap->contains(key); + if ( p) + return (*pmap)[p]; + return color_to_index_slow(bgr); +} + +inline int +DjVuPalette::color_to_index(const GPixel &p) +{ + return color_to_index(&p.b); +} + +inline void +DjVuPalette::index_to_color(int index, unsigned char *bgr) const +{ + const PColor &color = palette[index]; + bgr[0] = color.p[0]; + bgr[1] = color.p[1]; + bgr[2] = color.p[2]; +} + +inline void +DjVuPalette::index_to_color(int index, GPixel &p) const +{ + index_to_color(index, &p.b); +} + +inline void +DjVuPalette::get_color(int nth, GPixel &p) const +{ + index_to_color(colordata[nth], p); +} + + + +// ------------ THE END + +#ifdef HAVE_NAMESPACES +} +# ifndef NOT_USING_DJVU_NAMESPACE +using namespace DJVU; +# endif +#endif +#endif + + + + + |