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diff --git a/kviewshell/plugins/djvu/libdjvu/GScaler.h b/kviewshell/plugins/djvu/libdjvu/GScaler.h new file mode 100644 index 00000000..4843f6d0 --- /dev/null +++ b/kviewshell/plugins/djvu/libdjvu/GScaler.h @@ -0,0 +1,321 @@ +//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: GScaler.h,v 1.9 2003/11/07 22:08:21 leonb Exp $ +// $Name: release_3_5_15 $ + +#ifndef _GSCALER_H_ +#define _GSCALER_H_ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif +#if NEED_GNUG_PRAGMAS +# pragma interface +#endif + +// From: Leon Bottou, 1/31/2002 +// Almost equal to my initial code. + +#include "GException.h" +#include "GRect.h" +#include "GBitmap.h" +#include "GPixmap.h" + +#ifdef HAVE_NAMESPACES +namespace DJVU { +# ifdef NOT_DEFINED // Just to fool emacs c++ mode +} +#endif +#endif + + +/** @name GScaler.h + + Files #"GScaler.h"# and #"GScaler.cpp"# implement a fast bilinear + interpolation scheme to rescale a \Ref{GBitmap} or a \Ref{GPixmap}. + Common setup functions are implemented by the base class \Ref{GScaler}. + The actual function for rescaling a gray level image is implemented by + class \Ref{GBitmapScaler}. The actual function for rescaling a color + image is implemented by class \Ref{GPixmapScaler}. + + {\bf Remark} --- The bilinear interpolation code relies on fixed precision + tables. It becomes suboptimal when upsampling (i.e. zooming into) an + image by a factor greater than eight. High contrast images displayed at + high magnification may contain visible jaggies. + + @memo + Rescaling images with bilinear interpolation. + @author + L\'eon Bottou <leonb@research.att.com> + @version + #$Id: GScaler.h,v 1.9 2003/11/07 22:08:21 leonb Exp $# */ +//@{ + + +/** Base class for GBitmapScaler and GPixmapScaler. This base class + implements the common elements of class \Ref{GBitmapScaler} and + \Ref{GPixmapScaler}. Functions \Ref{set_input_size} and + \Ref{set_output_size} are used to specify the size of the input image and + the size of the output image. Functions \Ref{set_horz_ratio} and + \Ref{set_vert_ratio} may be used to override the scaling ratios computed + from the image sizes. You can then call function \Ref{get_input_rect} to + know which pixels of the input image are necessary to compute a specified + rectangular zone of the output image. The actual computation is then + performed by calling function #scale# in class \Ref{GBitmapScaler} and + \Ref{GPixmapScaler}. +*/ +class GScaler : public GPEnabled +{ +protected: + GScaler(); +public: + virtual ~GScaler(); + /** Sets the size of the input image. Argument #w# (resp. #h#) contains the + horizontal (resp. vertical) size of the input image. This size is used + to initialize the internal data structures of the scaler object. */ + void set_input_size(int w, int h); + /** Sets the size of the output image. Argument #w# (resp. #h#) contains the + horizontal (resp. vertical) size of the output image. This size is used + to initialize the internal data structures of the scaler object. */ + void set_output_size(int w, int h); + /** Sets the horizontal scaling ratio #numer/denom#. This function may be + used to force an exact scaling ratio. The scaling ratios are otherwise + derived from the sizes of the input and output images. */ + void set_horz_ratio(int numer, int denom); + /** Sets the vertical scaling ratio to #numer/denom#. This function may be + used to force an exact scaling ratio. The scaling ratios are otherwise + derived from the sizes of the input and output images. */ + void set_vert_ratio(int numer, int denom); + /** Computes which input pixels are required to compute specified output + pixels. Let us assume that we only need a part of the output + image. This part is defined by rectangle #desired_output#. Only a part + of the input image is necessary to compute the output pixels. Function + #get_input_rect# computes the coordinates of that part of the input + image, and stores them into rectangle #required_input#. */ + void get_input_rect( const GRect &desired_output, GRect &required_input ); +protected: + // The sizes + int inw, inh; + int xshift, yshift; + int redw, redh; + int outw, outh; + // Fixed point coordinates + int *vcoord; + GPBuffer<int> gvcoord; + int *hcoord; + GPBuffer<int> ghcoord; + // Helper + void make_rectangles(const GRect &desired, GRect &red, GRect &inp); +}; + + + +/** Fast rescaling code for gray level images. This class augments the base + class \Ref{GScaler} with a function for rescaling gray level + images. Function \Ref{GBitmapScaler::scale} computes an arbitrary segment + of the output image given the corresponding pixels in the input image. + + {\bf Example} --- The following functions returns an gray level image + (sixteen gray levels, size #nw# by #nh#) containing a rescaled version of + the input image #in#. + \begin{verbatim} + GBitmap *rescale_bitmap(const GBitmap &in, int nw, int nh) + { + int w = in.columns(); // Get input width + int h = in.raws(); // Get output width + GBitmapScaler scaler(w,h,nw,nh); // Creates bitmap scaler + GRect desired(0,0,nw,nh); // Desired output = complete bitmap + GRect provided(0,0,w,h); // Provided input = complete bitmap + GBitmap *out = new GBitmap; + scaler.scale(provided, in, desired, *out); // Rescale + out->change_grays(16); // Reduce to 16 gray levels + return out; + } + \end{verbatim} */ +class GBitmapScaler : public GScaler +{ +protected: + GBitmapScaler(void); + GBitmapScaler(int inw, int inh, int outw, int outh); +public: + /// Virtual destructor. + virtual ~GBitmapScaler(); + + /** Creates an empty GBitmapScaler. You must call functions + \Ref{GScaler::set_input_size} and \Ref{GScaler::set_output_size} before + calling any of the scaling functions. */ + static GP<GBitmapScaler> create(void) {return new GBitmapScaler(); } + + /** Creates a GBitmapScaler. The size of the input image is given by + #inw# and #inh#. This function internally calls + \Ref{GScaler::set_input_size} and \Ref{GScaler::set_output_size}. The + size of the output image is given by #outw# and #outh#. . */ + static GP<GBitmapScaler> create( + const int inw, const int inh, const int outw, const int outh) + { return new GBitmapScaler(inw,inh,outw,outh); } + + /** Computes a segment of the rescaled output image. The GBitmap object + #output# is overwritten with the segment of the output image specified + by the rectangle #desired_output#. The rectangle #provided_input# + specifies which segment of the input image is provided by the GBitmap + object #input#. An exception \Ref{GException} is thrown if the + rectangle #provided_input# is smaller then the rectangle + #required_input# returned by function \Ref{GScaler::get_input_rect}. + Note that the output image always contain 256 gray levels. You may want + to use function \Ref{GBitmap::change_grays} to reduce the number of gray + levels. */ + void scale( const GRect &provided_input, const GBitmap &input, + const GRect &desired_output, GBitmap &output ); +protected: + // Helpers + unsigned char *get_line(int, const GRect &, const GRect &, const GBitmap &); + // Temporaries + unsigned char *lbuffer; + GPBuffer<unsigned char> glbuffer; + unsigned char *conv; + GPBuffer<unsigned char> gconv; + unsigned char *p1; + GPBuffer<unsigned char> gp1; + unsigned char *p2; + GPBuffer<unsigned char> gp2; + int l1; + int l2; +}; + + +/** Fast rescaling code for color images. This class augments the base class + \Ref{GScaler} with a function for rescaling color images. Function + \Ref{GPixmapScaler::scale} computes an arbitrary segment of the output + image given the corresponding pixels in the input image. + + {\bf Example} --- The following functions returns a color image + of size #nw# by #nh# containing a rescaled version of + the input image #in#. + \begin{verbatim} + GPixmap *rescale_pixmap(const GPixmap &in, int nw, int nh) + { + int w = in.columns(); // Get input width + int h = in.raws(); // Get output width + GPixmapScaler scaler(w,h,nw,nh); // Creates bitmap scaler + GRect desired(0,0,nw,nh); // Desired output = complete image + GRect provided(0,0,w,h); // Provided input = complete image + GPixmap *out = new GPixmap; + scaler.scale(provided, in, desired, *out); // Rescale + return out; + } + \end{verbatim} + + */ +class GPixmapScaler : public GScaler +{ +protected: + GPixmapScaler(void); + GPixmapScaler(int inw, int inh, int outw, int outh); +public: + /// Virtual destructor. + virtual ~GPixmapScaler(); + + /** Creates an empty GPixmapScaler. You must call functions + \Ref{GScaler::set_input_size} and \Ref{GScaler::set_output_size} before + calling any of the scaling functions. */ + static GP<GPixmapScaler> create(void) {return new GPixmapScaler(); } + + /** Creates a GPixmapScaler. The size of the input image is given by + #inw# and #inh#. This function internally calls + \Ref{GScaler::set_input_size} and \Ref{GScaler::set_output_size}. The + size of the output image is given by #outw# and #outh#. . */ + static GP<GPixmapScaler> create( + const int inw, const int inh, const int outw, const int outh) + { return new GPixmapScaler(inw,inh,outw,outh); } + + /** Computes a segment of the rescaled output image. The pixmap #output# is + overwritten with the segment of the output image specified by the + rectangle #desired_output#. The rectangle #provided_input# specifies + which segment of the input image is provided in the pixmap #input#. An + exception \Ref{GException} is thrown if the rectangle #provided_input# + is smaller then the rectangle #required_input# returned by function + \Ref{GScaler::get_input_rect}. */ + void scale( const GRect &provided_input, const GPixmap &input, + const GRect &desired_output, GPixmap &output ); +protected: + // Helpers + GPixel *get_line(int, const GRect &, const GRect &, const GPixmap &); + // Temporaries + GPixel *lbuffer; + GPBufferBase glbuffer; + GPixel *p1; + GPBufferBase gp1; + GPixel *p2; + GPBufferBase gp2; + int l1; + int l2; +}; + + + + + +//@} + + + + +// -------- END + +#ifdef HAVE_NAMESPACES +} +# ifndef NOT_USING_DJVU_NAMESPACE +using namespace DJVU; +# endif +#endif +#endif |