//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, 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- +------------------------------------------------------------------
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#if NEED_GNUG_PRAGMAS
# pragma implementation
#endif
#include "GException.h"
#include "ByteStream.h"
#include "BSByteStream.h"
#include "DjVuPalette.h"
#include <stddef.h>
#include <stdlib.h>
#include <math.h>
#ifdef HAVE_NAMESPACES
namespace DJVU {
# ifdef NOT_DEFINED // Just to fool emacs c++ mode
}
#endif
#endif
#define CUBEBITS 4
#define CUBESIDE (1<<CUBEBITS)
#define CUBESIZE (CUBESIDE*CUBESIDE*CUBESIDE)
#define RMUL 5
#define GMUL 9
#define BMUL 2
#define SMUL (RMUL+GMUL+BMUL)
#define MAXPALETTESIZE 65535 // Limit for a 16 bit unsigned read.
inline unsigned char
umax(unsigned char a, unsigned char b)
{ return (a>b) ? a : b; }
inline unsigned char
umin(unsigned char a, unsigned char b)
{ return (a>b) ? b : a; }
inline float
fmin(float a, float b)
{ return (a>b) ? b : a; }
// ------- DJVUPALETTE
DjVuPalette::DjVuPalette()
: mask(0), hist(0), pmap(0)
{
}
DjVuPalette::~DjVuPalette()
{
delete hist;
delete pmap;
}
DjVuPalette&
DjVuPalette::operator=(const DjVuPalette &ref)
{
if (this != &ref)
{
delete hist;
delete pmap;
mask = 0;
palette = ref.palette;
colordata = ref.colordata;
}
return *this;
}
DjVuPalette::DjVuPalette(const DjVuPalette &ref)
: mask(0), hist(0), pmap(0)
{
this->operator=(ref);
}
// -------- HISTOGRAM ALLOCATION
void
DjVuPalette::allocate_hist()
{
if (! hist)
{
hist = new GMap<int,int>;
mask = 0;
}
else
{
GMap<int,int> *old = hist;
hist = new GMap<int,int>;
mask = (mask<<1)|(0x010101);
for (GPosition p = *old; p; ++p)
{
int k = old->key(p);
int w = (*old)[p];
(*hist)[k | mask] += w;
}
delete old;
}
}
// -------- PALETTE COMPUTATION
#ifndef NEED_DECODER_ONLY
struct PData
{
unsigned char p[3];
int w;
};
struct PBox
{
PData *data;
int colors;
int boxsize;
int sum;
};
int
DjVuPalette::bcomp (const void *a, const void *b)
{
return ((PData*)a)->p[0] - ((PData*)b)->p[0];
}
int
DjVuPalette::gcomp (const void *a, const void *b)
{
return ((PData*)a)->p[1] - ((PData*)b)->p[1];
}
int
DjVuPalette::rcomp (const void *a, const void *b)
{
return ((PData*)a)->p[2] - ((PData*)b)->p[2];
}
int
DjVuPalette::lcomp (const void *a, const void *b)
{
unsigned char *aa = ((PColor*)a)->p;
unsigned char *bb = ((PColor*)b)->p;
if (aa[3] != bb[3])
return aa[3]-bb[3];
else if (aa[2] != bb[2])
return aa[2]-bb[2];
else if (aa[1] != bb[1])
return aa[1]=bb[1];
else
return aa[0]-bb[0];
}
int
DjVuPalette::compute_palette(int maxcolors, int minboxsize)
{
if (!hist)
G_THROW( ERR_MSG("DjVuPalette.no_color") );
if (maxcolors<1 || maxcolors>MAXPALETTESIZE)
G_THROW( ERR_MSG("DjVuPalette.many_colors") );
// Paul Heckbert: "Color Image Quantization for Frame Buffer Display",
// SIGGRAPH '82 Proceedings, page 297. (also in ppmquant)
// Collect histogram colors
int sum = 0;
int ncolors = 0;
GTArray<PData> pdata;
{ // extra nesting for windows
for (GPosition p = *hist; p; ++p)
{
pdata.touch(ncolors);
PData &data = pdata[ncolors++];
int k = hist->key(p);
data.p[0] = (k>>16) & 0xff;
data.p[1] = (k>>8) & 0xff;
data.p[2] = (k) & 0xff;
data.w = (*hist)[p];
sum += data.w;
}
}
// Create first box
GList<PBox> boxes;
PBox newbox;
newbox.data = pdata;
newbox.colors = ncolors;
newbox.boxsize = 256;
newbox.sum = sum;
boxes.append(newbox);
// Repeat spliting boxes
while (boxes.size() < maxcolors)
{
// Find suitable box
GPosition p;
for (p=boxes; p; ++p)
if (boxes[p].colors>=2 && boxes[p].boxsize>minboxsize)
break;
if (! p)
break;
// Find box boundaries
PBox &splitbox = boxes[p];
unsigned char pmax[3];
unsigned char pmin[3];
pmax[0] = pmin[0] = splitbox.data->p[0];
pmax[1] = pmin[1] = splitbox.data->p[1];
pmax[2] = pmin[2] = splitbox.data->p[2];
{ // extra nesting for windows
for (int j=1; j<splitbox.colors; j++)
{
pmax[0] = umax(pmax[0], splitbox.data[j].p[0]);
pmax[1] = umax(pmax[1], splitbox.data[j].p[1]);
pmax[2] = umax(pmax[2], splitbox.data[j].p[2]);
pmin[0] = umin(pmin[0], splitbox.data[j].p[0]);
pmin[1] = umin(pmin[1], splitbox.data[j].p[1]);
pmin[2] = umin(pmin[2], splitbox.data[j].p[2]);
}
}
// Determine split direction and sort
int bl = pmax[0]-pmin[0];
int gl = pmax[1]-pmin[1];
int rl = pmax[2]-pmin[2];
splitbox.boxsize = (bl>gl ? (rl>bl ? rl : bl) : (rl>gl ? rl : gl));
if (splitbox.boxsize <= minboxsize)
continue;
if (gl == splitbox.boxsize)
qsort(splitbox.data, splitbox.colors, sizeof(PData), gcomp);
else if (rl == splitbox.boxsize)
qsort(splitbox.data, splitbox.colors, sizeof(PData), rcomp);
else
qsort(splitbox.data, splitbox.colors, sizeof(PData), bcomp);
// Find median
int lowercolors = 0;
int lowersum = 0;
while (lowercolors<splitbox.colors-1 && lowersum+lowersum<splitbox.sum)
lowersum += splitbox.data[lowercolors++].w;
// Compute new boxes
newbox.data = splitbox.data + lowercolors;
newbox.colors = splitbox.colors - lowercolors;
newbox.sum = splitbox.sum - lowersum;
splitbox.colors = lowercolors;
splitbox.sum = lowersum;
// Insert boxes at proper location
GPosition q;
for (q=p; q; ++q)
if (boxes[q].sum < newbox.sum)
break;
boxes.insert_before(q, newbox);
for (q=p; q; ++q)
if (boxes[q].sum < splitbox.sum)
break;
boxes.insert_before(q, boxes, p);
}
// Fill palette array
ncolors = 0;
palette.empty();
palette.resize(0,boxes.size()-1);
{ // extra nesting for windows
for (GPosition p=boxes; p; ++p)
{
PBox &box = boxes[p];
// Compute box representative color
float bsum = 0;
float gsum = 0;
float rsum = 0;
for (int j=0; j<box.colors; j++)
{
float w = (float)box.data[j].w;
bsum += box.data[j].p[0] * w;
gsum += box.data[j].p[1] * w;
rsum += box.data[j].p[2] * w;
}
PColor &color = palette[ncolors++];
color.p[0] = (unsigned char) fmin(255, bsum/box.sum);
color.p[1] = (unsigned char) fmin(255, gsum/box.sum);
color.p[2] = (unsigned char) fmin(255, rsum/box.sum);
color.p[3] = ( color.p[0]*BMUL + color.p[1]*GMUL + color.p[2]*RMUL) / SMUL;
}
}
// Save dominant color
PColor dcolor = palette[0];
// Sort palette colors in luminance order
qsort((PColor*)palette, ncolors, sizeof(PColor), lcomp);
// Clear invalid data
colordata.empty();
delete pmap;
pmap = 0;
// Return dominant color
return color_to_index_slow(dcolor.p);
}
int
DjVuPalette::compute_pixmap_palette(const GPixmap &pm, int ncolors, int minboxsize)
{
// Prepare histogram
histogram_clear();
{ // extra nesting for windows
for (int j=0; j<(int)pm.rows(); j++)
{
const GPixel *p = pm[j];
for (int i=0; i<(int)pm.columns(); i++)
histogram_add(p[i], 1);
}
}
// Compute palette
return compute_palette(ncolors, minboxsize);
}
#endif
// -------- QUANTIZATION
void
DjVuPalette::allocate_pmap()
{
if (! pmap)
pmap = new GMap<int,int>;
}
int
DjVuPalette::color_to_index_slow(const unsigned char *bgr)
{
PColor *pal = palette;
const int ncolors = palette.size();
if (! ncolors)
G_THROW( ERR_MSG("DjVuPalette.not_init") );
// Should be able to do better
int found = 0;
int founddist = 3*256*256;
{ // extra nesting for windows
for (int i=0; i<ncolors; i++)
{
int bd = bgr[0] - pal[i].p[0];
int gd = bgr[1] - pal[i].p[1];
int rd = bgr[2] - pal[i].p[2];
int dist = (bd*bd)+(gd*gd)+(rd*rd);
if (dist < founddist)
{
found = i;
founddist = dist;
}
}
}
// Store in pmap
if (pmap && pmap->size()<0x8000)
{
int key = (bgr[0]<<16)|(bgr[1]<<8)|(bgr[2]);
(*pmap)[key] = found;
}
// Return
return found;
}
#ifndef NEED_DECODER_ONLY
void
DjVuPalette::quantize(GPixmap &pm)
{
{ // extra nesting for windows
for (int j=0; j<(int)pm.rows(); j++)
{
GPixel *p = pm[j];
for (int i=0; i<(int)pm.columns(); i++)
index_to_color(color_to_index(p[i]), p[i]);
}
}
}
int
DjVuPalette::compute_palette_and_quantize(GPixmap &pm, int maxcolors, int minboxsize)
{
int result = compute_pixmap_palette(pm, maxcolors, minboxsize);
quantize(pm);
return result;
}
void
DjVuPalette::color_correct(double corr)
{
const int palettesize = palette.size();
if (palettesize > 0)
{
// Copy colors
int i;
GTArray<GPixel> pix(0,palettesize-1);
GPixel *r = pix;
PColor *q = palette;
for (i=0; i<palettesize; i++)
{
r[i].b = q[i].p[0];
r[i].g = q[i].p[1];
r[i].r = q[i].p[2];
}
// Apply color correction
GPixmap::color_correct(corr, r, palettesize);
// Restore colors
for (i=0; i<palettesize; i++)
{
q[i].p[0] = r[i].b;
q[i].p[1] = r[i].g;
q[i].p[2] = r[i].r;
}
}
}
#endif
// -------- ENCODE AND DECODE
#define DJVUPALETTEVERSION 0
void
DjVuPalette::encode_rgb_entries(ByteStream &bs) const
{
const int palettesize = palette.size();
{ // extra nesting for windows
for (int c=0; c<palettesize; c++)
{
unsigned char p[3];
p[2] = palette[c].p[0];
p[1] = palette[c].p[1];
p[0] = palette[c].p[2];
bs.writall((const void*)p, 3);
}
}
}
void
DjVuPalette::encode(GP<ByteStream> gbs) const
{
ByteStream &bs=*gbs;
const int palettesize = palette.size();
const int datasize = colordata.size();
// Code version number
int version = DJVUPALETTEVERSION;
if (datasize>0) version |= 0x80;
bs.write8(version);
// Code palette
bs.write16(palettesize);
{ // extra nesting for windows
for (int c=0; c<palettesize; c++)
{
unsigned char p[3];
p[0] = palette[c].p[0];
p[1] = palette[c].p[1];
p[2] = palette[c].p[2];
bs.writall((const void*)p, 3);
}
}
// Code colordata
if (datasize > 0)
{
bs.write24(datasize);
GP<ByteStream> gbsb=BSByteStream::create(gbs, 50);
ByteStream &bsb=*gbsb;
for (int d=0; d<datasize; d++)
bsb.write16(colordata[d]);
}
}
void
DjVuPalette::decode_rgb_entries(ByteStream &bs, const int palettesize)
{
palette.resize(0,palettesize-1);
{ // extra nesting for windows
for (int c=0; c<palettesize; c++)
{
unsigned char p[3];
bs.readall((void*)p, 3);
palette[c].p[0] = p[2];
palette[c].p[1] = p[1];
palette[c].p[2] = p[0];
palette[c].p[3] = (p[0]*BMUL+p[1]*GMUL+p[2]*RMUL)/SMUL;
}
}
}
void
DjVuPalette::decode(GP<ByteStream> gbs)
{
ByteStream &bs=*gbs;
// Make sure that everything is clear
delete hist;
delete pmap;
hist = 0;
pmap = 0;
mask = 0;
// Code version
int version = bs.read8();
if ( (version & 0x7f) != DJVUPALETTEVERSION)
G_THROW( ERR_MSG("DjVuPalette.bad_version") );
// Code palette
const int palettesize = bs.read16();
if (palettesize<0 || palettesize>MAXPALETTESIZE)
G_THROW( ERR_MSG("DjVuPalette.bad_palette") );
palette.resize(0,palettesize-1);
{ // extra nesting for windows
for (int c=0; c<palettesize; c++)
{
unsigned char p[3];
bs.readall((void*)p, 3);
palette[c].p[0] = p[0];
palette[c].p[1] = p[1];
palette[c].p[2] = p[2];
palette[c].p[3] = (p[0]*BMUL+p[1]*GMUL+p[2]*RMUL)/SMUL;
}
}
// Code data
if (version & 0x80)
{
int datasize = bs.read24();
if (datasize<0)
G_THROW( ERR_MSG("DjVuPalette.bad_palette") );
colordata.resize(0,datasize-1);
GP<ByteStream> gbsb=BSByteStream::create(gbs);
ByteStream &bsb=*gbsb;
{ // extra nesting for windows
for (int d=0; d<datasize; d++)
{
short s = bsb.read16();
if (s<0 || s>=palettesize)
G_THROW( ERR_MSG("DjVuPalette.bad_palette") );
colordata[d] = s;
}
}
}
}
#ifdef HAVE_NAMESPACES
}
# ifndef NOT_USING_DJVU_NAMESPACE
using namespace DJVU;
# endif
#endif