oimageeffect.cpp

Go to the documentation of this file.

/* This file is part of the KDE libraries
    Copyright (C) 1998, 1999, 2001, 2002 Daniel M. Duley <mosfet@kde.org>
    (C) 1998, 1999 Christian Tibirna <ctibirna@total.net>
    (C) 1998, 1999 Dirk A. Mueller <mueller@kde.org>
    (C) 2000 Josef Weidendorfer <weidendo@in.tum.de>

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

// $Id: oimageeffect.cpp,v 1.5 2004/03/13 19:51:49 zecke Exp $

#include <math.h>

#include <qimage.h>
#include <stdlib.h>

#include <opie2/oimageeffect.h>
#include <opie2/odebug.h>

#define MaxRGB 255L
#define DegreesToRadians(x) ((x)*M_PI/180.0)

using namespace std;
using namespace Opie::Core;

namespace Opie {
namespace Ui   {

inline unsigned int intensityValue(unsigned int color)
{
    return((unsigned int)((0.299*qRed(color) +
                           0.587*qGreen(color) +
                           0.1140000000000001*qBlue(color))));
}

//======================================================================
//
// Gradient effects
//
//======================================================================

QImage OImageEffect::gradient(const QSize &size, const QColor &ca,
        const QColor &cb, GradientType eff, int ncols)
{
    int rDiff, gDiff, bDiff;
    int rca, gca, bca, rcb, gcb, bcb;

    QImage image(size, 32);

    if (size.width() == 0 || size.height() == 0) {
      odebug << "WARNING: OImageEffect::gradient: invalid image" << oendl;
      return image;
    }

    register int x, y;

    rDiff = (rcb = cb.red())   - (rca = ca.red());
    gDiff = (gcb = cb.green()) - (gca = ca.green());
    bDiff = (bcb = cb.blue())  - (bca = ca.blue());

    if( eff == VerticalGradient || eff == HorizontalGradient ){

        uint *p;
        uint rgb;

        register int rl = rca << 16;
        register int gl = gca << 16;
        register int bl = bca << 16;

        if( eff == VerticalGradient ) {

            int rcdelta = ((1<<16) / size.height()) * rDiff;
            int gcdelta = ((1<<16) / size.height()) * gDiff;
            int bcdelta = ((1<<16) / size.height()) * bDiff;

            for ( y = 0; y < size.height(); y++ ) {
                p = (uint *) image.scanLine(y);

                rl += rcdelta;
                gl += gcdelta;
                bl += bcdelta;

                rgb = qRgb( (rl>>16), (gl>>16), (bl>>16) );

                for( x = 0; x < size.width(); x++ ) {
                    *p = rgb;
                    p++;
                }
            }

        }
        else {                  // must be HorizontalGradient

            unsigned int *o_src = (unsigned int *)image.scanLine(0);
            unsigned int *src = o_src;

            int rcdelta = ((1<<16) / size.width()) * rDiff;
            int gcdelta = ((1<<16) / size.width()) * gDiff;
            int bcdelta = ((1<<16) / size.width()) * bDiff;

            for( x = 0; x < size.width(); x++) {

                rl += rcdelta;
                gl += gcdelta;
                bl += bcdelta;

                *src++ = qRgb( (rl>>16), (gl>>16), (bl>>16));
            }

            src = o_src;

            // Believe it or not, manually copying in a for loop is faster
            // than calling memcpy for each scanline (on the order of ms...).
            // I think this is due to the function call overhead (mosfet).

            for (y = 1; y < size.height(); ++y) {

                p = (unsigned int *)image.scanLine(y);
                src = o_src;
                for(x=0; x < size.width(); ++x)
                    *p++ = *src++;
            }
        }
    }

    else {

        float rfd, gfd, bfd;
        float rd = rca, gd = gca, bd = bca;

        unsigned char *xtable[3];
        unsigned char *ytable[3];

        unsigned int w = size.width(), h = size.height();
        xtable[0] = new unsigned char[w];
        xtable[1] = new unsigned char[w];
        xtable[2] = new unsigned char[w];
        ytable[0] = new unsigned char[h];
        ytable[1] = new unsigned char[h];
        ytable[2] = new unsigned char[h];
        w*=2, h*=2;

        if ( eff == DiagonalGradient || eff == CrossDiagonalGradient) {
            // Diagonal dgradient code inspired by BlackBox (mosfet)
            // BlackBox dgradient is (C) Brad Hughes, <bhughes@tcac.net> and
            // Mike Cole <mike@mydot.com>.

            rfd = (float)rDiff/w;
            gfd = (float)gDiff/w;
            bfd = (float)bDiff/w;

            int dir;
            for (x = 0; x < size.width(); x++, rd+=rfd, gd+=gfd, bd+=bfd) {
                dir = eff == DiagonalGradient? x : size.width() - x - 1;
                xtable[0][dir] = (unsigned char) rd;
                xtable[1][dir] = (unsigned char) gd;
                xtable[2][dir] = (unsigned char) bd;
            }
            rfd = (float)rDiff/h;
            gfd = (float)gDiff/h;
            bfd = (float)bDiff/h;
            rd = gd = bd = 0;
            for (y = 0; y < size.height(); y++, rd+=rfd, gd+=gfd, bd+=bfd) {
                ytable[0][y] = (unsigned char) rd;
                ytable[1][y] = (unsigned char) gd;
                ytable[2][y] = (unsigned char) bd;
            }

            for (y = 0; y < size.height(); y++) {
                unsigned int *scanline = (unsigned int *)image.scanLine(y);
                for (x = 0; x < size.width(); x++) {
                    scanline[x] = qRgb(xtable[0][x] + ytable[0][y],
                                       xtable[1][x] + ytable[1][y],
                                       xtable[2][x] + ytable[2][y]);
                }
            }
        }

        else if (eff == RectangleGradient ||
                 eff == PyramidGradient ||
                 eff == PipeCrossGradient ||
                 eff == EllipticGradient)
        {
            int rSign = rDiff>0? 1: -1;
            int gSign = gDiff>0? 1: -1;
            int bSign = bDiff>0? 1: -1;

            rfd = (float)rDiff / size.width();
            gfd = (float)gDiff / size.width();
            bfd = (float)bDiff / size.width();

            rd = (float)rDiff/2;
            gd = (float)gDiff/2;
            bd = (float)bDiff/2;

            for (x = 0; x < size.width(); x++, rd-=rfd, gd-=gfd, bd-=bfd)
            {
                xtable[0][x] = (unsigned char) abs((int)rd);
                xtable[1][x] = (unsigned char) abs((int)gd);
                xtable[2][x] = (unsigned char) abs((int)bd);
            }

            rfd = (float)rDiff/size.height();
            gfd = (float)gDiff/size.height();
            bfd = (float)bDiff/size.height();

            rd = (float)rDiff/2;
            gd = (float)gDiff/2;
            bd = (float)bDiff/2;

            for (y = 0; y < size.height(); y++, rd-=rfd, gd-=gfd, bd-=bfd)
            {
                ytable[0][y] = (unsigned char) abs((int)rd);
                ytable[1][y] = (unsigned char) abs((int)gd);
                ytable[2][y] = (unsigned char) abs((int)bd);
            }
            unsigned int rgb;
            int h = (size.height()+1)>>1;
            for (y = 0; y < h; y++) {
                unsigned int *sl1 = (unsigned int *)image.scanLine(y);
                unsigned int *sl2 = (unsigned int *)image.scanLine(QMAX(size.height()-y-1, y));

                int w = (size.width()+1)>>1;
                int x2 = size.width()-1;

                for (x = 0; x < w; x++, x2--) {
                    rgb = 0;
                    if (eff == PyramidGradient) {
                        rgb = qRgb(rcb-rSign*(xtable[0][x]+ytable[0][y]),
                                   gcb-gSign*(xtable[1][x]+ytable[1][y]),
                                   bcb-bSign*(xtable[2][x]+ytable[2][y]));
                    }
                    if (eff == RectangleGradient) {
                        rgb = qRgb(rcb - rSign *
                                   QMAX(xtable[0][x], ytable[0][y]) * 2,
                                   gcb - gSign *
                                   QMAX(xtable[1][x], ytable[1][y]) * 2,
                                   bcb - bSign *
                                   QMAX(xtable[2][x], ytable[2][y]) * 2);
                    }
                    if (eff == PipeCrossGradient) {
                        rgb = qRgb(rcb - rSign *
                                   QMIN(xtable[0][x], ytable[0][y]) * 2,
                                   gcb - gSign *
                                   QMIN(xtable[1][x], ytable[1][y]) * 2,
                                   bcb - bSign *
                                   QMIN(xtable[2][x], ytable[2][y]) * 2);
                    }
                    if (eff == EllipticGradient) {
                        rgb = qRgb(rcb - rSign *
                                   (int)sqrt((xtable[0][x]*xtable[0][x] +
                                              ytable[0][y]*ytable[0][y])*2.0),
                                   gcb - gSign *
                                   (int)sqrt((xtable[1][x]*xtable[1][x] +
                                              ytable[1][y]*ytable[1][y])*2.0),
                                   bcb - bSign *
                                   (int)sqrt((xtable[2][x]*xtable[2][x] +
                                              ytable[2][y]*ytable[2][y])*2.0));
                    }

                    sl1[x] = sl2[x] = rgb;
                    sl1[x2] = sl2[x2] = rgb;
                }
            }
        }

        delete [] xtable[0];
        delete [] xtable[1];
        delete [] xtable[2];
        delete [] ytable[0];
        delete [] ytable[1];
        delete [] ytable[2];
    }

    // dither if necessary
    if (ncols && (QPixmap::defaultDepth() < 15 )) {
        if ( ncols < 2 || ncols > 256 )
            ncols = 3;
        QColor *dPal = new QColor[ncols];
        for (int i=0; i<ncols; i++) {
            dPal[i].setRgb ( rca + rDiff * i / ( ncols - 1 ),
                             gca + gDiff * i / ( ncols - 1 ),
                             bca + bDiff * i / ( ncols - 1 ) );
        }
    dither(image, dPal, ncols);
        delete [] dPal;
    }

    return image;
}


// -----------------------------------------------------------------------------

//CT this was (before Dirk A. Mueller's speedup changes)
//   merely the same code as in the above method, but it's supposedly
//   way less performant since it introduces a lot of supplementary tests
//   and simple math operations for the calculus of the balance.
//      (surprizingly, it isn't less performant, in the contrary :-)
//   Yes, I could have merged them, but then the excellent performance of
//   the balanced code would suffer with no other gain than a mere
//   source code and byte code size economy.

QImage OImageEffect::unbalancedGradient(const QSize &size, const QColor &ca,
        const QColor &cb, GradientType eff, int xfactor, int yfactor,
        int ncols)
{
    int dir; // general parameter used for direction switches

    bool _xanti = false , _yanti = false;

    if (xfactor < 0) _xanti = true; // negative on X direction
    if (yfactor < 0) _yanti = true; // negative on Y direction

    xfactor = abs(xfactor);
    yfactor = abs(yfactor);

    if (!xfactor) xfactor = 1;
    if (!yfactor) yfactor = 1;

    if (xfactor > 200 ) xfactor = 200;
    if (yfactor > 200 ) yfactor = 200;


    //    float xbal = xfactor/5000.;
    //    float ybal = yfactor/5000.;
    float xbal = xfactor/30./size.width();
    float ybal = yfactor/30./size.height();
    float rat;

    int rDiff, gDiff, bDiff;
    int rca, gca, bca, rcb, gcb, bcb;

    QImage image(size, 32);

    if (size.width() == 0 || size.height() == 0) {
      odebug << "WARNING: OImageEffect::unbalancedGradient : invalid image" << oendl;
      return image;
    }

    register int x, y;
    unsigned int *scanline;

    rDiff = (rcb = cb.red())   - (rca = ca.red());
    gDiff = (gcb = cb.green()) - (gca = ca.green());
    bDiff = (bcb = cb.blue())  - (bca = ca.blue());

    if( eff == VerticalGradient || eff == HorizontalGradient){
        QColor cRow;

        uint *p;
        uint rgbRow;

        if( eff == VerticalGradient) {
          for ( y = 0; y < size.height(); y++ ) {
            dir = _yanti ? y : size.height() - 1 - y;
            p = (uint *) image.scanLine(dir);
            rat =  1 - exp( - (float)y  * ybal );

            cRow.setRgb( rcb - (int) ( rDiff * rat ),
                         gcb - (int) ( gDiff * rat ),
                         bcb - (int) ( bDiff * rat ) );

            rgbRow = cRow.rgb();

            for( x = 0; x < size.width(); x++ ) {
              *p = rgbRow;
              p++;
            }
          }
        }
        else {

          unsigned int *src = (unsigned int *)image.scanLine(0);
          for(x = 0; x < size.width(); x++ )
            {
              dir = _xanti ? x : size.width() - 1 - x;
              rat = 1 - exp( - (float)x  * xbal );

              src[dir] = qRgb(rcb - (int) ( rDiff * rat ),
                            gcb - (int) ( gDiff * rat ),
                            bcb - (int) ( bDiff * rat ));
            }

          // Believe it or not, manually copying in a for loop is faster
          // than calling memcpy for each scanline (on the order of ms...).
          // I think this is due to the function call overhead (mosfet).

          for(y = 1; y < size.height(); ++y)
            {
              scanline = (unsigned int *)image.scanLine(y);
              for(x=0; x < size.width(); ++x)
                scanline[x] = src[x];
            }
        }
    }

    else {
      int w=size.width(), h=size.height();

      unsigned char *xtable[3];
      unsigned char *ytable[3];
      xtable[0] = new unsigned char[w];
      xtable[1] = new unsigned char[w];
      xtable[2] = new unsigned char[w];
      ytable[0] = new unsigned char[h];
      ytable[1] = new unsigned char[h];
      ytable[2] = new unsigned char[h];

      if ( eff == DiagonalGradient || eff == CrossDiagonalGradient)
        {
          for (x = 0; x < w; x++) {
              dir = _xanti ? x : w - 1 - x;
              rat = 1 - exp( - (float)x * xbal );

              xtable[0][dir] = (unsigned char) ( rDiff/2 * rat );
              xtable[1][dir] = (unsigned char) ( gDiff/2 * rat );
              xtable[2][dir] = (unsigned char) ( bDiff/2 * rat );
          }

          for (y = 0; y < h; y++) {
              dir = _yanti ? y : h - 1 - y;
              rat =  1 - exp( - (float)y  * ybal );

              ytable[0][dir] = (unsigned char) ( rDiff/2 * rat );
              ytable[1][dir] = (unsigned char) ( gDiff/2 * rat );
              ytable[2][dir] = (unsigned char) ( bDiff/2 * rat );
          }

          for (y = 0; y < h; y++) {
              unsigned int *scanline = (unsigned int *)image.scanLine(y);
              for (x = 0; x < w; x++) {
                  scanline[x] = qRgb(rcb - (xtable[0][x] + ytable[0][y]),
                                     gcb - (xtable[1][x] + ytable[1][y]),
                                     bcb - (xtable[2][x] + ytable[2][y]));
              }
          }
        }

      else if (eff == RectangleGradient ||
               eff == PyramidGradient ||
               eff == PipeCrossGradient ||
               eff == EllipticGradient)
      {
          int rSign = rDiff>0? 1: -1;
          int gSign = gDiff>0? 1: -1;
          int bSign = bDiff>0? 1: -1;

          for (x = 0; x < w; x++)
            {
                dir = _xanti ? x : w - 1 - x;
                rat =  1 - exp( - (float)x * xbal );

                xtable[0][dir] = (unsigned char) abs((int)(rDiff*(0.5-rat)));
                xtable[1][dir] = (unsigned char) abs((int)(gDiff*(0.5-rat)));
                xtable[2][dir] = (unsigned char) abs((int)(bDiff*(0.5-rat)));
            }

          for (y = 0; y < h; y++)
          {
              dir = _yanti ? y : h - 1 - y;

              rat =  1 - exp( - (float)y * ybal );

              ytable[0][dir] = (unsigned char) abs((int)(rDiff*(0.5-rat)));
              ytable[1][dir] = (unsigned char) abs((int)(gDiff*(0.5-rat)));
              ytable[2][dir] = (unsigned char) abs((int)(bDiff*(0.5-rat)));
          }

          for (y = 0; y < h; y++) {
              unsigned int *scanline = (unsigned int *)image.scanLine(y);
              for (x = 0; x < w; x++) {
                  if (eff == PyramidGradient)
                  {
                      scanline[x] = qRgb(rcb-rSign*(xtable[0][x]+ytable[0][y]),
                                         gcb-gSign*(xtable[1][x]+ytable[1][y]),
                                         bcb-bSign*(xtable[2][x]+ytable[2][y]));
                  }
                  if (eff == RectangleGradient)
                  {
                      scanline[x] = qRgb(rcb - rSign *
                                         QMAX(xtable[0][x], ytable[0][y]) * 2,
                                         gcb - gSign *
                                         QMAX(xtable[1][x], ytable[1][y]) * 2,
                                         bcb - bSign *
                                         QMAX(xtable[2][x], ytable[2][y]) * 2);
                  }
                  if (eff == PipeCrossGradient)
                  {
                      scanline[x] = qRgb(rcb - rSign *
                                         QMIN(xtable[0][x], ytable[0][y]) * 2,
                                         gcb - gSign *
                                         QMIN(xtable[1][x], ytable[1][y]) * 2,
                                         bcb - bSign *
                                         QMIN(xtable[2][x], ytable[2][y]) * 2);
                  }
                  if (eff == EllipticGradient)
                  {
                      scanline[x] = qRgb(rcb - rSign *
                                         (int)sqrt((xtable[0][x]*xtable[0][x] +
                                                    ytable[0][y]*ytable[0][y])*2.0),
                                         gcb - gSign *
                                         (int)sqrt((xtable[1][x]*xtable[1][x] +
                                                    ytable[1][y]*ytable[1][y])*2.0),
                                         bcb - bSign *
                                         (int)sqrt((xtable[2][x]*xtable[2][x] +
                                                    ytable[2][y]*ytable[2][y])*2.0));
                  }
              }
          }
      }

      if (ncols && (QPixmap::defaultDepth() < 15 )) {
          if ( ncols < 2 || ncols > 256 )
              ncols = 3;
          QColor *dPal = new QColor[ncols];
          for (int i=0; i<ncols; i++) {
              dPal[i].setRgb ( rca + rDiff * i / ( ncols - 1 ),
                               gca + gDiff * i / ( ncols - 1 ),
                               bca + bDiff * i / ( ncols - 1 ) );
          }
          dither(image, dPal, ncols);
          delete [] dPal;
      }

      delete [] xtable[0];
      delete [] xtable[1];
      delete [] xtable[2];
      delete [] ytable[0];
      delete [] ytable[1];
      delete [] ytable[2];

    }

    return image;
}


//======================================================================
//
// Intensity effects
//
//======================================================================


/* This builds a 256 byte unsigned char lookup table with all
 * the possible percent values prior to applying the effect, then uses
 * integer math for the pixels. For any image larger than 9x9 this will be
 * less expensive than doing a float operation on the 3 color components of
 * each pixel. (mosfet)
 */

QImage& OImageEffect::intensity(QImage &image, float percent)
{
    if (image.width() == 0 || image.height() == 0) {
      odebug << "WARNING: OImageEffect::intensity : invalid image" << oendl;
      return image;
    }

    int segColors = image.depth() > 8 ? 256 : image.numColors();
    unsigned char *segTbl = new unsigned char[segColors];
    int pixels = image.depth() > 8 ? image.width()*image.height() :
        image.numColors();
    unsigned int *data = image.depth() > 8 ? (unsigned int *)image.bits() :
        (unsigned int *)image.colorTable();

    bool brighten = (percent >= 0);
    if(percent < 0)
        percent = -percent;

    if(brighten){ // keep overflow check out of loops
        for(int i=0; i < segColors; ++i){
            int tmp = (int)(i*percent);
            if(tmp > 255)
                tmp = 255;
            segTbl[i] = tmp;
        }
    }
    else{
        for(int i=0; i < segColors; ++i){
            int tmp = (int)(i*percent);
            if(tmp < 0)
                tmp = 0;
            segTbl[i] = tmp;
        }
    }

    if(brighten){ // same here
        for(int i=0; i < pixels; ++i){
            int r = qRed(data[i]);
            int g = qGreen(data[i]);
            int b = qBlue(data[i]);
            int a = qAlpha(data[i]);
            r = r + segTbl[r] > 255 ? 255 : r + segTbl[r];
            g = g + segTbl[g] > 255 ? 255 : g + segTbl[g];
            b = b + segTbl[b] > 255 ? 255 : b + segTbl[b];
            data[i] = qRgba(r, g, b,a);
        }
    }
    else{
        for(int i=0; i < pixels; ++i){
            int r = qRed(data[i]);
            int g = qGreen(data[i]);
            int b = qBlue(data[i]);
            int a = qAlpha(data[i]);
            r = r - segTbl[r] < 0 ? 0 : r - segTbl[r];
            g = g - segTbl[g] < 0 ? 0 : g - segTbl[g];
            b = b - segTbl[b] < 0 ? 0 : b - segTbl[b];
            data[i] = qRgba(r, g, b, a);
        }
    }
    delete [] segTbl;

    return image;
}

QImage& OImageEffect::channelIntensity(QImage &image, float percent,
                                       RGBComponent channel)
{
    if (image.width() == 0 || image.height() == 0) {
      odebug << "WARNING: OImageEffect::channelIntensity : invalid image" << oendl;
      return image;
    }

    int segColors = image.depth() > 8 ? 256 : image.numColors();
    unsigned char *segTbl = new unsigned char[segColors];
    int pixels = image.depth() > 8 ? image.width()*image.height() :
        image.numColors();
    unsigned int *data = image.depth() > 8 ? (unsigned int *)image.bits() :
        (unsigned int *)image.colorTable();
    bool brighten = (percent >= 0);
    if(percent < 0)
        percent = -percent;

    if(brighten){ // keep overflow check out of loops
        for(int i=0; i < segColors; ++i){
            int tmp = (int)(i*percent);
            if(tmp > 255)
                tmp = 255;
            segTbl[i] = tmp;
        }
    }
    else{
        for(int i=0; i < segColors; ++i){
            int tmp = (int)(i*percent);
            if(tmp < 0)
                tmp = 0;
            segTbl[i] = tmp;
        }
    }

    if(brighten){ // same here
        if(channel == Red){ // and here ;-)
            for(int i=0; i < pixels; ++i){
                int c = qRed(data[i]);
                c = c + segTbl[c] > 255 ? 255 : c + segTbl[c];
                data[i] = qRgba(c, qGreen(data[i]), qBlue(data[i]), qAlpha(data[i]));
            }
        }
        if(channel == Green){
            for(int i=0; i < pixels; ++i){
                int c = qGreen(data[i]);
                c = c + segTbl[c] > 255 ? 255 : c + segTbl[c];
                data[i] = qRgba(qRed(data[i]), c, qBlue(data[i]), qAlpha(data[i]));
            }
        }
        else{
            for(int i=0; i < pixels; ++i){
                int c = qBlue(data[i]);
                c = c + segTbl[c] > 255 ? 255 : c + segTbl[c];
                data[i] = qRgba(qRed(data[i]), qGreen(data[i]), c, qAlpha(data[i]));
            }
        }

    }
    else{
        if(channel == Red){
            for(int i=0; i < pixels; ++i){
                int c = qRed(data[i]);
                c = c - segTbl[c] < 0 ? 0 : c - segTbl[c];
                data[i] = qRgba(c, qGreen(data[i]), qBlue(data[i]), qAlpha(data[i]));
            }
        }
        if(channel == Green){
            for(int i=0; i < pixels; ++i){
                int c = qGreen(data[i]);
                c = c - segTbl[c] < 0 ? 0 : c - segTbl[c];
                data[i] = qRgba(qRed(data[i]), c, qBlue(data[i]), qAlpha(data[i]));
            }
        }
        else{
            for(int i=0; i < pixels; ++i){
                int c = qBlue(data[i]);
                c = c - segTbl[c] < 0 ? 0 : c - segTbl[c];
                data[i] = qRgba(qRed(data[i]), qGreen(data[i]), c, qAlpha(data[i]));
            }
        }
    }
    delete [] segTbl;

    return image;
}

// Modulate an image with an RBG channel of another image
//
QImage& OImageEffect::modulate(QImage &image, QImage &modImage, bool reverse,
        ModulationType type, int factor, RGBComponent channel)
{
    if (image.width() == 0 || image.height() == 0 ||
        modImage.width() == 0 || modImage.height() == 0) {
          odebug << "WARNING: OImageEffect::modulate : invalid image" << oendl;
          return image;
    }

    int r, g, b, h, s, v, a;
    QColor clr;
    int mod=0;
    unsigned int x1, x2, y1, y2;
    register int x, y;

    // for image, we handle only depth 32
    if (image.depth()<32) image = image.convertDepth(32);

    // for modImage, we handle depth 8 and 32
    if (modImage.depth()<8) modImage = modImage.convertDepth(8);

    unsigned int *colorTable2 = (modImage.depth()==8) ?
                                 modImage.colorTable():0;
    unsigned int *data1, *data2;
    unsigned char *data2b;
    unsigned int color1, color2;

    x1 = image.width();    y1 = image.height();
    x2 = modImage.width(); y2 = modImage.height();

    for (y = 0; y < (int)y1; y++) {
        data1 =  (unsigned int *) image.scanLine(y);
        data2 =  (unsigned int *) modImage.scanLine( y%y2 );
        data2b = (unsigned char *) modImage.scanLine( y%y2 );

        x=0;
        while(x < (int)x1) {
          color2 = (colorTable2) ? colorTable2[*data2b] : *data2;
          if (reverse) {
              color1 = color2;
              color2 = *data1;
          }
          else
              color1 = *data1;

          if (type == Intensity || type == Contrast) {
              r = qRed(color1);
              g = qGreen(color1);
              b = qBlue(color1);
              if (channel != All) {
                mod = (channel == Red) ? qRed(color2) :
                    (channel == Green) ? qGreen(color2) :
                    (channel == Blue) ? qBlue(color2) :
                    (channel == Gray) ? qGray(color2) : 0;
                mod = mod*factor/50;
              }

              if (type == Intensity) {
                if (channel == All) {
                  r += r * factor/50 * qRed(color2)/256;
                  g += g * factor/50 * qGreen(color2)/256;
                  b += b * factor/50 * qBlue(color2)/256;
                }
                else {
                  r += r * mod/256;
                  g += g * mod/256;
                  b += b * mod/256;
                }
              }
              else { // Contrast
                if (channel == All) {
                  r += (r-128) * factor/50 * qRed(color2)/128;
                  g += (g-128) * factor/50 * qGreen(color2)/128;
                  b += (b-128) * factor/50 * qBlue(color2)/128;
                }
                else {
                  r += (r-128) * mod/128;
                  g += (g-128) * mod/128;
                  b += (b-128) * mod/128;
                }
              }

              if (r<0) r=0; if (r>255) r=255;
              if (g<0) g=0; if (g>255) g=255;
              if (b<0) b=0; if (b>255) b=255;
              a = qAlpha(*data1);
              *data1 = qRgba(r, g, b, a);
          }
          else if (type == Saturation || type == HueShift) {
              clr.setRgb(color1);
              clr.hsv(&h, &s, &v);
              mod = (channel == Red) ? qRed(color2) :
                    (channel == Green) ? qGreen(color2) :
                    (channel == Blue) ? qBlue(color2) :
                    (channel == Gray) ? qGray(color2) : 0;
              mod = mod*factor/50;

              if (type == Saturation) {
                  s -= s * mod/256;
                  if (s<0) s=0; if (s>255) s=255;
              }
              else { // HueShift
                h += mod;
                while(h<0) h+=360;
                h %= 360;
              }

              clr.setHsv(h, s, v);
              a = qAlpha(*data1);
              *data1 = clr.rgb() | ((uint)(a & 0xff) << 24);
          }
          data1++; data2++; data2b++; x++;
          if ( (x%x2) ==0) { data2 -= x2; data2b -= x2; }
        }
    }
    return image;
}



//======================================================================
//
// Blend effects
//
//======================================================================


// Nice and fast direct pixel manipulation
QImage& OImageEffect::blend(const QColor& clr, QImage& dst, float opacity)
{
    if (dst.width() <= 0 || dst.height() <= 0)
        return dst;

    if (opacity < 0.0 || opacity > 1.0) {
        odebug << "WARNING: OImageEffect::blend : invalid opacity. Range [0, 1] " << oendl;
        return dst;
    }

    int depth = dst.depth();
    if (depth != 32)
        dst = dst.convertDepth(32);

    int pixels = dst.width() * dst.height();
    int rcol, gcol, bcol;
    clr.rgb(&rcol, &gcol, &bcol);

#ifdef WORDS_BIGENDIAN   // ARGB (skip alpha)
    register unsigned char *data = (unsigned char *)dst.bits() + 1;
#else                    // BGRA
    register unsigned char *data = (unsigned char *)dst.bits();
#endif

    for (register int i=0; i<pixels; i++)
    {
#ifdef WORDS_BIGENDIAN
        *(data++) += (unsigned char)((rcol - *data) * opacity);
        *(data++) += (unsigned char)((gcol - *data) * opacity);
        *(data++) += (unsigned char)((bcol - *data) * opacity);
#else
        *(data++) += (unsigned char)((bcol - *data) * opacity);
        *(data++) += (unsigned char)((gcol - *data) * opacity);
        *(data++) += (unsigned char)((rcol - *data) * opacity);
#endif
        data++; // skip alpha
    }
    return dst;
}

// Nice and fast direct pixel manipulation
QImage& OImageEffect::blend(QImage& src, QImage& dst, float opacity)
{
    if (src.width() <= 0 || src.height() <= 0)
        return dst;
    if (dst.width() <= 0 || dst.height() <= 0)
        return dst;

    if (src.width() != dst.width() || src.height() != dst.height()) {
        odebug << "WARNING: OImageEffect::blend : src and destination images are not the same size" << oendl;
        return dst;
    }

    if (opacity < 0.0 || opacity > 1.0) {
        odebug << "WARNING: OImageEffect::blend : invalid opacity. Range [0, 1]" << oendl;
        return dst;
    }

    if (src.depth() != 32) src = src.convertDepth(32);
    if (dst.depth() != 32) dst = dst.convertDepth(32);

    int pixels = src.width() * src.height();
#ifdef WORDS_BIGENDIAN   // ARGB (skip alpha)
    register unsigned char *data1 = (unsigned char *)dst.bits() + 1;
    register unsigned char *data2 = (unsigned char *)src.bits() + 1;
#else                    // BGRA
    register unsigned char *data1 = (unsigned char *)dst.bits();
    register unsigned char *data2 = (unsigned char *)src.bits();
#endif

    for (register int i=0; i<pixels; i++)
    {
#ifdef WORDS_BIGENDIAN
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
#else
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
        *(data1++) += (unsigned char)((*(data2++) - *data1) * opacity);
#endif
        data1++; // skip alpha
        data2++;
    }

    return dst;
}


QImage& OImageEffect::blend(QImage &image, float initial_intensity,
                            const QColor &bgnd, GradientType eff,
                            bool anti_dir)
{
    if (image.width() == 0 || image.height() == 0 || image.depth()!=32 ) {
        odebug << "WARNING: OImageEffect::blend : invalid image" << oendl;
        return image;
    }

    int r_bgnd = bgnd.red(), g_bgnd = bgnd.green(), b_bgnd = bgnd.blue();
    int r, g, b;
    int ind;

    unsigned int xi, xf, yi, yf;
    unsigned int a;

    // check the boundaries of the initial intesity param
    float unaffected = 1;
    if (initial_intensity >  1) initial_intensity =  1;
    if (initial_intensity < -1) initial_intensity = -1;
    if (initial_intensity < 0) {
        unaffected = 1. + initial_intensity;
        initial_intensity = 0;
    }


    float intensity = initial_intensity;
    float var = 1. - initial_intensity;

    if (anti_dir) {
        initial_intensity = intensity = 1.;
        var = -var;
    }

    register int x, y;

    unsigned int *data =  (unsigned int *)image.bits();

    int image_width = image.width(); //Those can't change
    int image_height = image.height();


    if( eff == VerticalGradient || eff == HorizontalGradient ) {

        // set the image domain to apply the effect to
        xi = 0, xf = image_width;
        yi = 0, yf = image_height;
        if (eff == VerticalGradient) {
            if (anti_dir) yf = (int)(image_height * unaffected);
            else yi = (int)(image_height * (1 - unaffected));
        }
        else {
            if (anti_dir) xf = (int)(image_width * unaffected);
            else xi = (int)(image_height * (1 - unaffected));
        }

        var /= (eff == VerticalGradient?yf-yi:xf-xi);

        int ind_base;
        for (y = yi; y < (int)yf; y++) {
            intensity = eff == VerticalGradient? intensity + var :
                initial_intensity;
            ind_base = image_width  * y ;
            for (x = xi; x < (int)xf ; x++) {
                if (eff == HorizontalGradient) intensity += var;
                ind = x + ind_base;
                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);
            }
        }
    }
    else if (eff == DiagonalGradient  || eff == CrossDiagonalGradient) {
        float xvar = var / 2 / image_width;  // / unaffected;
        float yvar = var / 2 / image_height; // / unaffected;
        float tmp;

        for (x = 0; x < image_width ; x++) {
            tmp =  xvar * (eff == DiagonalGradient? x : image.width()-x-1);
            ind = x;
            for (y = 0; y < image_height ; y++) {
                intensity = initial_intensity + tmp + yvar * y;

                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);

                ind += image_width;
            }
        }
    }

    else if (eff == RectangleGradient || eff == EllipticGradient) {
        float xvar;
        float yvar;

        for (x = 0; x < image_width / 2 + image_width % 2; x++) {
            xvar = var / image_width  * (image_width - x*2/unaffected-1);
            for (y = 0; y < image_height / 2 + image_height % 2; y++) {
                yvar = var / image_height   * (image_height - y*2/unaffected -1);

                if (eff == RectangleGradient)
                    intensity = initial_intensity + QMAX(xvar, yvar);
                else
                    intensity = initial_intensity + sqrt(xvar * xvar + yvar * yvar);
                if (intensity > 1) intensity = 1;
                if (intensity < 0) intensity = 0;

                //NW
                ind = x + image_width  * y ;
                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);

                //NE
                ind = image_width - x - 1 + image_width  * y ;
                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);
            }
        }

        //CT  loop is doubled because of stupid central row/column issue.
        //    other solution?
        for (x = 0; x < image_width / 2; x++) {
            xvar = var / image_width  * (image_width - x*2/unaffected-1);
            for (y = 0; y < image_height / 2; y++) {
                yvar = var / image_height   * (image_height - y*2/unaffected -1);

                if (eff == RectangleGradient)
                    intensity = initial_intensity + QMAX(xvar, yvar);
                else
                    intensity = initial_intensity + sqrt(xvar * xvar + yvar * yvar);
                if (intensity > 1) intensity = 1;
                if (intensity < 0) intensity = 0;

                //SW
                ind = x + image_width  * (image_height - y -1) ;
                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);

                //SE
                ind = image_width-x-1 + image_width * (image_height - y - 1) ;
                r = qRed  (data[ind]) + (int)(intensity *
                                              (r_bgnd - qRed  (data[ind])));
                g = qGreen(data[ind]) + (int)(intensity *
                                              (g_bgnd - qGreen(data[ind])));
                b = qBlue (data[ind]) + (int)(intensity *
                                              (b_bgnd - qBlue (data[ind])));
                if (r > 255) r = 255; if (r < 0 ) r = 0;
                if (g > 255) g = 255; if (g < 0 ) g = 0;
                if (b > 255) b = 255; if (b < 0 ) b = 0;
                a = qAlpha(data[ind]);
                data[ind] = qRgba(r, g, b, a);
            }
        }
    }
    else odebug << "OImageEffect::blend effect not implemented" << oendl;
    return image;
}

// Not very efficient as we create a third big image...
//
QImage& OImageEffect::blend(QImage &image1, QImage &image2,
                            GradientType gt, int xf, int yf)
{
  if (image1.width() == 0 || image1.height() == 0 ||
      image2.width() == 0 || image2.height() == 0)
    return image1;

  QImage image3;

  image3 = OImageEffect::unbalancedGradient(image1.size(),
                                    QColor(0,0,0), QColor(255,255,255),
                                    gt, xf, yf, 0);

  return blend(image1,image2,image3, Red); // Channel to use is arbitrary
}

// Blend image2 into image1, using an RBG channel of blendImage
//
QImage& OImageEffect::blend(QImage &image1, QImage &image2,
                            QImage &blendImage, RGBComponent channel)
{
    if (image1.width() == 0 || image1.height() == 0 ||
        image2.width() == 0 || image2.height() == 0 ||
        blendImage.width() == 0 || blendImage.height() == 0) {
            odebug << "OImageEffect::blend effect invalid image" << oendl;
            return image1;
    }

    int r, g, b;
    int ind1, ind2, ind3;

    unsigned int x1, x2, x3, y1, y2, y3;
    unsigned int a;

    register int x, y;

    // for image1 and image2, we only handle depth 32
    if (image1.depth()<32) image1 = image1.convertDepth(32);
    if (image2.depth()<32) image2 = image2.convertDepth(32);

    // for blendImage, we handle depth 8 and 32
    if (blendImage.depth()<8) blendImage = blendImage.convertDepth(8);

    unsigned int *colorTable3 = (blendImage.depth()==8) ?
                                 blendImage.colorTable():0;

    unsigned int *data1 =  (unsigned int *)image1.bits();
    unsigned int *data2 =  (unsigned int *)image2.bits();
    unsigned int *data3   =  (unsigned int *)blendImage.bits();
    unsigned char *data3b =  (unsigned char *)blendImage.bits();
    unsigned int color3;

    x1 = image1.width();     y1 = image1.height();
    x2 = image2.width();     y2 = image2.height();
    x3 = blendImage.width(); y3 = blendImage.height();

    for (y = 0; y < (int)y1; y++) {
        ind1 = x1*y;
        ind2 = x2*(y%y2);
        ind3 = x3*(y%y3);

        x=0;
        while(x < (int)x1) {
          color3 = (colorTable3) ? colorTable3[data3b[ind3]] : data3[ind3];

          a = (channel == Red) ? qRed(color3) :
              (channel == Green) ? qGreen(color3) :
              (channel == Blue) ? qBlue(color3) : qGray(color3);

          r = (a*qRed(data1[ind1]) + (256-a)*qRed(data2[ind2]))/256;
          g = (a*qGreen(data1[ind1]) + (256-a)*qGreen(data2[ind2]))/256;
          b = (a*qBlue(data1[ind1]) + (256-a)*qBlue(data2[ind2]))/256;

          a = qAlpha(data1[ind1]);
          data1[ind1] = qRgba(r, g, b, a);

          ind1++; ind2++; ind3++; x++;
          if ( (x%x2) ==0) ind2 -= x2;
          if ( (x%x3) ==0) ind3 -= x3;
        }
    }
    return image1;
}


//======================================================================
//
// Hash effects
//
//======================================================================

unsigned int OImageEffect::lHash(unsigned int c)
{
    unsigned char r = qRed(c), g = qGreen(c), b = qBlue(c), a = qAlpha(c);
    unsigned char nr, ng, nb;
    nr =(r >> 1) + (r >> 2); nr = nr > r ? 0 : nr;
    ng =(g >> 1) + (g >> 2); ng = ng > g ? 0 : ng;
    nb =(b >> 1) + (b >> 2); nb = nb > b ? 0 : nb;

    return qRgba(nr, ng, nb, a);
}


// -----------------------------------------------------------------------------

unsigned int OImageEffect::uHash(unsigned int c)
{
    unsigned char r = qRed(c), g = qGreen(c), b = qBlue(c), a = qAlpha(c);
    unsigned char nr, ng, nb;
    nr = r + (r >> 3); nr = nr < r ? ~0 : nr;
    ng = g + (g >> 3); ng = ng < g ? ~0 : ng;
    nb = b + (b >> 3); nb = nb < b ? ~0 : nb;

    return qRgba(nr, ng, nb, a);
}


// -----------------------------------------------------------------------------

QImage& OImageEffect::hash(QImage &image, Lighting lite, unsigned int spacing)
{
    if (image.width() == 0 || image.height() == 0) {
        odebug << "OImageEffect::hash effect invalid image" << oendl;
        return image;
    }

    register int x, y;
    unsigned int *data =  (unsigned int *)image.bits();
    unsigned int ind;

    //CT no need to do it if not enough space
    if ((lite == NorthLite ||
         lite == SouthLite)&&
        (unsigned)image.height() < 2+spacing) return image;
    if ((lite == EastLite ||
         lite == WestLite)&&
        (unsigned)image.height() < 2+spacing) return image;

    if (lite == NorthLite || lite == SouthLite) {
        for (y = 0 ; y < image.height(); y = y + 2 + spacing) {
            for (x = 0; x < image.width(); x++) {
                ind = x + image.width() * y;
                data[ind] = lite==NorthLite?uHash(data[ind]):lHash(data[ind]);

                ind = ind + image.width();
                data[ind] = lite==NorthLite?lHash(data[ind]):uHash(data[ind]);
            }
        }
    }

    else if (lite == EastLite || lite == WestLite) {
        for (y = 0 ; y < image.height(); y++) {
            for (x = 0; x < image.width(); x = x + 2 + spacing) {
                ind = x + image.width() * y;
                data[ind] = lite==EastLite?uHash(data[ind]):lHash(data[ind]);

                ind++;
                data[ind] = lite==EastLite?lHash(data[ind]):uHash(data[ind]);
            }
        }
    }

    else if (lite == NWLite || lite == SELite) {
        for (y = 0 ; y < image.height(); y++) {
            for (x = 0;
                 x < (int)(image.width() - ((y & 1)? 1 : 0) * spacing);
                 x = x + 2 + spacing) {
                ind = x + image.width() * y + ((y & 1)? 1 : 0);
                data[ind] = lite==NWLite?uHash(data[ind]):lHash(data[ind]);

                ind++;
                data[ind] = lite==NWLite?lHash(data[ind]):uHash(data[ind]);
            }
        }
    }

    else if (lite == SWLite || lite == NELite) {
        for (y = 0 ; y < image.height(); y++) {
            for (x = 0  + ((y & 1)? 1 : 0); x < image.width(); x = x + 2 + spacing) {
                ind = x + image.width() * y - ((y & 1)? 1 : 0);
                data[ind] = lite==SWLite?uHash(data[ind]):lHash(data[ind]);

                ind++;
                data[ind] = lite==SWLite?lHash(data[ind]):uHash(data[ind]);
            }
        }
    }

    return image;
}


//======================================================================
//
// Flatten effects
//
//======================================================================

QImage& OImageEffect::flatten(QImage &img, const QColor &ca,
                            const QColor &cb, int ncols)
{
    if (img.width() == 0 || img.height() == 0)
      return img;

    // a bitmap is easy...
    if (img.depth() == 1) {
        img.setColor(0, ca.rgb());
        img.setColor(1, cb.rgb());
        return img;
    }

    int r1 = ca.red(); int r2 = cb.red();
    int g1 = ca.green(); int g2 = cb.green();
    int b1 = ca.blue(); int b2 = cb.blue();
    int min = 0, max = 255;

    QRgb col;

    // Get minimum and maximum greylevel.
    if (img.numColors()) {
        // pseudocolor
        for (int i = 0; i < img.numColors(); i++) {
            col = img.color(i);
            int mean = (qRed(col) + qGreen(col) + qBlue(col)) / 3;
            min = QMIN(min, mean);
            max = QMAX(max, mean);
        }
    } else {
        // truecolor
        for (int y=0; y < img.height(); y++)
            for (int x=0; x < img.width(); x++) {
                col = img.pixel(x, y);
                int mean = (qRed(col) + qGreen(col) + qBlue(col)) / 3;
                min = QMIN(min, mean);
                max = QMAX(max, mean);
            }
    }

    // Conversion factors
    float sr = ((float) r2 - r1) / (max - min);
    float sg = ((float) g2 - g1) / (max - min);
    float sb = ((float) b2 - b1) / (max - min);


    // Repaint the image
    if (img.numColors()) {
        for (int i=0; i < img.numColors(); i++) {
            col = img.color(i);
            int mean = (qRed(col) + qGreen(col) + qBlue(col)) / 3;
            int r = (int) (sr * (mean - min) + r1 + 0.5);
            int g = (int) (sg * (mean - min) + g1 + 0.5);
            int b = (int) (sb * (mean - min) + b1 + 0.5);
            img.setColor(i, qRgba(r, g, b, qAlpha(col)));
        }
    } else {
        for (int y=0; y < img.height(); y++)
            for (int x=0; x < img.width(); x++) {
                col = img.pixel(x, y);
                int mean = (qRed(col) + qGreen(col) + qBlue(col)) / 3;
                int r = (int) (sr * (mean - min) + r1 + 0.5);
                int g = (int) (sg * (mean - min) + g1 + 0.5);
                int b = (int) (sb * (mean - min) + b1 + 0.5);
                img.setPixel(x, y, qRgba(r, g, b, qAlpha(col)));
            }
    }


    // Dither if necessary
    if ( (ncols <= 0) || ((img.numColors() != 0) && (img.numColors() <= ncols)))
        return img;

    if (ncols == 1) ncols++;
    if (ncols > 256) ncols = 256;

    QColor *pal = new QColor[ncols];
    sr = ((float) r2 - r1) / (ncols - 1);
    sg = ((float) g2 - g1) / (ncols - 1);
    sb = ((float) b2 - b1) / (ncols - 1);

    for (int i=0; i<ncols; i++)
        pal[i] = QColor(r1 + int(sr*i), g1 + int(sg*i), b1 + int(sb*i));

    dither(img, pal, ncols);

    delete[] pal;
    return img;
}


//======================================================================
//
// Fade effects
//
//======================================================================

QImage& OImageEffect::fade(QImage &img, float val, const QColor &color)
{
    if (img.width() == 0 || img.height() == 0)
      return img;

    // We don't handle bitmaps
    if (img.depth() == 1)
        return img;

    unsigned char tbl[256];
    for (int i=0; i<256; i++)
        tbl[i] = (int) (val * i + 0.5);

    int red = color.red();
    int green = color.green();
    int blue = color.blue();

    QRgb col;
    int r, g, b, cr, cg, cb;

    if (img.depth() <= 8) {
        // pseudo color
        for (int i=0; i<img.numColors(); i++) {
            col = img.color(i);
            cr = qRed(col); cg = qGreen(col); cb = qBlue(col);
            if (cr > red)
                r = cr - tbl[cr - red];
            else
                r = cr + tbl[red - cr];
            if (cg > green)
                g = cg - tbl[cg - green];
            else
                g = cg + tbl[green - cg];
            if (cb > blue)
                b = cb - tbl[cb - blue];
            else
                b = cb + tbl[blue - cb];
            img.setColor(i, qRgba(r, g, b, qAlpha(col)));
        }

    } else {
        // truecolor
        for (int y=0; y<img.height(); y++) {
            QRgb *data = (QRgb *) img.scanLine(y);
            for (int x=0; x<img.width(); x++) {
                col = *data;
                cr = qRed(col); cg = qGreen(col); cb = qBlue(col);
                if (cr > red)
                    r = cr - tbl[cr - red];
                else
                    r = cr + tbl[red - cr];
                if (cg > green)
                    g = cg - tbl[cg - green];
                else
                    g = cg + tbl[green - cg];
                if (cb > blue)
                    b = cb - tbl[cb - blue];
                else
                    b = cb + tbl[blue - cb];
                *data++ = qRgba(r, g, b, qAlpha(col));
            }
        }
    }

    return img;
}

//======================================================================
//
// Color effects
//
//======================================================================

// This code is adapted from code (C) Rik Hemsley <rik@kde.org>
//
// The formula used (r + b + g) /3 is different from the qGray formula
// used by Qt.  This is because our formula is much much faster.  If,
// however, it turns out that this is producing sub-optimal images,
// then it will have to change (kurt)
//
// It does produce lower quality grayscale ;-) Use fast == true for the fast
// algorithm, false for the higher quality one (mosfet).
QImage& OImageEffect::toGray(QImage &img, bool fast)
{
    if (img.width() == 0 || img.height() == 0)
      return img;

    if(fast){
        if (img.depth() == 32) {
            register uchar * r(img.bits());
            register uchar * g(img.bits() + 1);
            register uchar * b(img.bits() + 2);

            uchar * end(img.bits() + img.numBytes());

            while (r != end) {

                *r = *g = *b = (((*r + *g) >> 1) + *b) >> 1; // (r + b + g) / 3

                r += 4;
                g += 4;
                b += 4;
            }
        }
        else
        {
            for (int i = 0; i < img.numColors(); i++)
            {
                register uint r = qRed(img.color(i));
                register uint g = qGreen(img.color(i));
                register uint b = qBlue(img.color(i));

                register uint gray = (((r + g) >> 1) + b) >> 1;
                img.setColor(i, qRgba(gray, gray, gray, qAlpha(img.color(i))));
            }
        }
    }
    else{
        int pixels = img.depth() > 8 ? img.width()*img.height() :
            img.numColors();
        unsigned int *data = img.depth() > 8 ? (unsigned int *)img.bits() :
            (unsigned int *)img.colorTable();
        int val, i;
        for(i=0; i < pixels; ++i){
            val = qGray(data[i]);
            data[i] = qRgba(val, val, val, qAlpha(data[i]));
        }
    }
    return img;
}

// CT 29Jan2000 - desaturation algorithms
QImage& OImageEffect::desaturate(QImage &img, float desat)
{
    if (img.width() == 0 || img.height() == 0)
      return img;

    if (desat < 0) desat = 0.;
    if (desat > 1) desat = 1.;
    int pixels = img.depth() > 8 ? img.width()*img.height() :
        img.numColors();
    unsigned int *data = img.depth() > 8 ? (unsigned int *)img.bits() :
        (unsigned int *)img.colorTable();
    int h, s, v, i;
    QColor clr; // keep constructor out of loop (mosfet)
    for(i=0; i < pixels; ++i){
        clr.setRgb(data[i]);
        clr.hsv(&h, &s, &v);
        clr.setHsv(h, (int)(s * (1. - desat)), v);
        data[i] = clr.rgb();
    }
    return img;
}

// Contrast stuff (mosfet)
QImage& OImageEffect::contrast(QImage &img, int c)
{
    if (img.width() == 0 || img.height() == 0)
      return img;

    if(c > 255)
        c = 255;
    if(c < -255)
        c =  -255;
    int pixels = img.depth() > 8 ? img.width()*img.height() :
        img.numColors();
    unsigned int *data = img.depth() > 8 ? (unsigned int *)img.bits() :
        (unsigned int *)img.colorTable();
    int i, r, g, b;
    for(i=0; i < pixels; ++i){
        r = qRed(data[i]);
        g = qGreen(data[i]);
        b = qBlue(data[i]);
        if(qGray(data[i]) <= 127){
            if(r - c <= 255)
                r -= c;
            if(g - c <= 255)
                g -= c;
            if(b - c <= 255)
                b -= c;
        }
        else{
            if(r + c <= 255)
                r += c;
            if(g + c <= 255)
                g += c;
            if(b + c <= 255)
                b += c;
        }
        data[i] = qRgba(r, g, b, qAlpha(data[i]));
    }
    return(img);
}

//======================================================================
//
// Dithering effects
//
//======================================================================

// adapted from kFSDither (C) 1997 Martin Jones (mjones@kde.org)
//
// Floyd-Steinberg dithering
// Ref: Bitmapped Graphics Programming in C++
//      Marv Luse, Addison-Wesley Publishing, 1993.
QImage& OImageEffect::dither(QImage &img, const QColor *palette, int size)
{
    if (img.width() == 0 || img.height() == 0 ||
        palette == 0 || img.depth() <= 8)
      return img;

    QImage dImage( img.width(), img.height(), 8, size );
    int i;

    dImage.setNumColors( size );
    for ( i = 0; i < size; i++ )
        dImage.setColor( i, palette[ i ].rgb() );

    int *rerr1 = new int [ img.width() * 2 ];
    int *gerr1 = new int [ img.width() * 2 ];
    int *berr1 = new int [ img.width() * 2 ];

    memset( rerr1, 0, sizeof( int ) * img.width() * 2 );
    memset( gerr1, 0, sizeof( int ) * img.width() * 2 );
    memset( berr1, 0, sizeof( int ) * img.width() * 2 );

    int *rerr2 = rerr1 + img.width();
    int *gerr2 = gerr1 + img.width();
    int *berr2 = berr1 + img.width();

    for ( int j = 0; j < img.height(); j++ )
    {
        uint *ip = (uint * )img.scanLine( j );
        uchar *dp = dImage.scanLine( j );

        for ( i = 0; i < img.width(); i++ )
        {
            rerr1[i] = rerr2[i] + qRed( *ip );
            rerr2[i] = 0;
            gerr1[i] = gerr2[i] + qGreen( *ip );
            gerr2[i] = 0;
            berr1[i] = berr2[i] + qBlue( *ip );
            berr2[i] = 0;
            ip++;
        }

        *dp++ = nearestColor( rerr1[0], gerr1[0], berr1[0], palette, size );

        for ( i = 1; i < img.width()-1; i++ )
        {
            int indx = nearestColor( rerr1[i], gerr1[i], berr1[i], palette, size );
            *dp = indx;

            int rerr = rerr1[i];
            rerr -= palette[indx].red();
            int gerr = gerr1[i];
            gerr -= palette[indx].green();
            int berr = berr1[i];
            berr -= palette[indx].blue();

            // diffuse red error
            rerr1[ i+1 ] += ( rerr * 7 ) >> 4;
            rerr2[ i-1 ] += ( rerr * 3 ) >> 4;
            rerr2[  i  ] += ( rerr * 5 ) >> 4;
            rerr2[ i+1 ] += ( rerr ) >> 4;

            // diffuse green error
            gerr1[ i+1 ] += ( gerr * 7 ) >> 4;
            gerr2[ i-1 ] += ( gerr * 3 ) >> 4;
            gerr2[  i  ] += ( gerr * 5 ) >> 4;
            gerr2[ i+1 ] += ( gerr ) >> 4;

            // diffuse red error
            berr1[ i+1 ] += ( berr * 7 ) >> 4;
            berr2[ i-1 ] += ( berr * 3 ) >> 4;
            berr2[  i  ] += ( berr * 5 ) >> 4;
            berr2[ i+1 ] += ( berr ) >> 4;

            dp++;
        }

        *dp = nearestColor( rerr1[i], gerr1[i], berr1[i], palette, size );
    }

    delete [] rerr1;
    delete [] gerr1;
    delete [] berr1;

    img = dImage;
    return img;
}

int OImageEffect::nearestColor( int r, int g, int b, const QColor *palette, int size )
{
    if (palette == 0)
      return 0;

    int dr = palette[0].red() - r;
    int dg = palette[0].green() - g;
    int db = palette[0].blue() - b;

    int minDist =  dr*dr + dg*dg + db*db;
    int nearest = 0;

    for (int i = 1; i < size; i++ )
    {
        dr = palette[i].red() - r;
        dg = palette[i].green() - g;
        db = palette[i].blue() - b;

        int dist = dr*dr + dg*dg + db*db;

        if ( dist < minDist )
        {
            minDist = dist;
            nearest = i;
        }
    }

    return nearest;
}

bool OImageEffect::blend(
    const QImage & upper,
    const QImage & lower,
    QImage & output
)
{
  if (
      upper.width()  > lower.width()  ||
      upper.height() > lower.height() ||
      upper.depth() != 32             ||
      lower.depth() != 32
  )
  {
      odebug << "OImageEffect::blend : Sizes not correct" << oendl;
      return false;
  }

  output = lower.copy();

  register uchar *i, *o;
  register int a;
  register int col;
  register int w = upper.width();
  int row(upper.height() - 1);

  do {

    i = upper.scanLine(row);
    o = output.scanLine(row);

    col = w << 2;
    --col;

    do {

      while (!(a = i[col]) && (col != 3)) {
        --col; --col; --col; --col;
      }

      --col;
      o[col] += ((i[col] - o[col]) * a) >> 8;

      --col;
      o[col] += ((i[col] - o[col]) * a) >> 8;

      --col;
      o[col] += ((i[col] - o[col]) * a) >> 8;

    } while (col--);

  } while (row--);

  return true;
}

#if 0
// Not yet...
bool OImageEffect::blend(
    const QImage & upper,
    const QImage & lower,
    QImage & output,
    const QRect & destRect
)
{
  output = lower.copy();
  return output;
}

#endif

bool OImageEffect::blend(
    int &x, int &y,
    const QImage & upper,
    const QImage & lower,
    QImage & output
)
{
  int cx=0, cy=0, cw=upper.width(), ch=upper.height();

  if ( upper.width() + x > lower.width()  ||
      upper.height() + y > lower.height() ||
      x < 0 || y < 0 ||
      upper.depth() != 32 || lower.depth() != 32 )
  {
    if ( x > lower.width() || y > lower.height() ) return false;
    if ( upper.width()<=0 || upper.height() <= 0 ) return false;
    if ( lower.width()<=0 || lower.height() <= 0 ) return false;

    if (x<0) {cx=-x; cw+=x; x=0; };
    if (cw + x > lower.width()) { cw=lower.width()-x; };
    if (y<0) {cy=-y; ch+=y; y=0; };
    if (ch + y > lower.height()) { ch=lower.height()-y; };

    if ( cx >= upper.width() || cy >= upper.height() ) return true;
    if ( cw <= 0 || ch <= 0 ) return true;
  }

  output.create(cw,ch,32);
//  output.setAlphaBuffer(true); // I should do some benchmarks to see if
        // this is worth the effort

  register QRgb *i, *o, *b;

  register int a;
  register int j,k;
  for (j=0; j<ch; j++)
  {
    b=reinterpret_cast<QRgb *>(&lower.scanLine(y+j) [ (x+cw) << 2 ]);
    i=reinterpret_cast<QRgb *>(&upper.scanLine(cy+j)[ (cx+cw) << 2 ]);
    o=reinterpret_cast<QRgb *>(&output.scanLine(j)  [ cw << 2 ]);

    k=cw-1;
    --b; --i; --o;
    do
    {
      while ( !(a=qAlpha(*i)) && k>0 )
      {
        i--;
//      *o=0;
        *o=*b;
        --o; --b;
        k--;
      };
//      *o=0xFF;
      *o = qRgb(qRed(*b) + (((qRed(*i) - qRed(*b)) * a) >> 8),
                qGreen(*b) + (((qGreen(*i) - qGreen(*b)) * a) >> 8),
                qBlue(*b) + (((qBlue(*i) - qBlue(*b)) * a) >> 8));
      --i; --o; --b;
    } while (k--);
  }

  return true;
}

bool OImageEffect::blendOnLower(
    int x, int y,
    const QImage & upper,
    const QImage & lower
)
{
  int cx=0, cy=0, cw=upper.width(), ch=upper.height();

  if ( upper.depth() != 32 || lower.depth() != 32 ) return false;
  if ( x + cw > lower.width()  ||
      y + ch > lower.height() ||
      x < 0 || y < 0 )
  {
    if ( x > lower.width() || y > lower.height() ) return true;
    if ( upper.width()<=0 || upper.height() <= 0 ) return true;
    if ( lower.width()<=0 || lower.height() <= 0 ) return true;

    if (x<0) {cx=-x; cw+=x; x=0; };
    if (cw + x > lower.width()) { cw=lower.width()-x; };
    if (y<0) {cy=-y; ch+=y; y=0; };
    if (ch + y > lower.height()) { ch=lower.height()-y; };

    if ( cx >= upper.width() || cy >= upper.height() ) return true;
    if ( cw <= 0 || ch <= 0 ) return true;
  }

  register uchar *i, *b;
  register int a;
  register int k;

  for (int j=0; j<ch; j++)
  {
    b=&lower.scanLine(y+j) [ (x+cw) << 2 ];
    i=&upper.scanLine(cy+j)[ (cx+cw) << 2 ];

    k=cw-1;
    --b; --i;
    do
    {
#ifndef WORDS_BIGENDIAN
      while ( !(a=*i) && k>0 )
#else
      while ( !(a=*(i-3)) && k>0 )
#endif
      {
        i-=4; b-=4; k--;
      };

#ifndef WORDS_BIGENDIAN
      --i; --b;
      *b += ( ((*i - *b) * a) >> 8 );
      --i; --b;
      *b += ( ((*i - *b) * a) >> 8 );
      --i; --b;
      *b += ( ((*i - *b) * a) >> 8 );
      --i; --b;
#else
      *b += ( ((*i - *b) * a) >> 8 );
      --i; --b;
      *b += ( ((*i - *b) * a) >> 8 );
      --i; --b;
      *b += ( ((*i - *b) * a) >> 8 );
      i -= 2; b -= 2;
#endif
    } while (k--);
  }

  return true;
}

// For selected icons
QImage& OImageEffect::selectedImage( QImage &img, const QColor &col )
{
    return blend( col, img, 0.5);
}

//
// ===================================================================
// Effects originally ported from ImageMagick for PixiePlus, plus a few
// new ones. (mosfet 12/29/01)
// ===================================================================
//

void OImageEffect::normalize(QImage &img)
{
    int *histogram, threshold_intensity, intense;
    int x, y, i;

    unsigned int gray_value;
    unsigned int *normalize_map;
    unsigned int high, low;

    // allocate histogram and normalize map
    histogram = (int *)calloc(MaxRGB+1, sizeof(int));
    normalize_map = (unsigned int *)malloc((MaxRGB+1)*sizeof(unsigned int));
    if(!normalize_map || !histogram){
        owarn << "Unable to allocate normalize histogram and map" << oendl;
        free(normalize_map);
        free(histogram);
        return;
    }

    // form histogram
    if(img.depth() > 8){  // DirectClass
        unsigned int *data;
        for(y=0; y < img.height(); ++y){
            data = (unsigned int *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                gray_value = intensityValue(data[x]);
                histogram[gray_value]++;
            }
        }
    }
    else{ // PsudeoClass
        unsigned char *data;
        unsigned int *cTable = img.colorTable();
        for(y=0; y < img.height(); ++y){
            data = (unsigned char *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                gray_value = intensityValue(*(cTable+data[x]));
                histogram[gray_value]++;
            }
        }
    }

    // find histogram boundaries by locating the 1 percent levels
    threshold_intensity = (img.width()*img.height())/100;
    intense = 0;
    for(low=0; low < MaxRGB; ++low){
        intense+=histogram[low];
        if(intense > threshold_intensity)
            break;
    }
    intense=0;
    for(high=MaxRGB; high != 0; --high){
        intense+=histogram[high];
        if(intense > threshold_intensity)
            break;
    }

    if (low == high){
        // Unreasonable contrast;  use zero threshold to determine boundaries.
        threshold_intensity=0;
        intense=0;
        for(low=0; low < MaxRGB; ++low){
            intense+=histogram[low];
            if(intense > threshold_intensity)
                break;
        }
        intense=0;
        for(high=MaxRGB; high != 0; --high)
        {
            intense+=histogram[high];
            if(intense > threshold_intensity)
                break;
        }
        if(low == high)
            return;  // zero span bound
    }

    // Stretch the histogram to create the normalized image mapping.
    for(i=0; i <= MaxRGB; i++){
        if (i < (int) low)
            normalize_map[i]=0;
        else{
            if(i > (int) high)
                normalize_map[i]=MaxRGB;
            else
                normalize_map[i]=(MaxRGB-1)*(i-low)/(high-low);
        }
    }
    // Normalize
    if(img.depth() > 8){ // DirectClass
        unsigned int *data;
        for(y=0; y < img.height(); ++y){
            data = (unsigned int *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                data[x] = qRgba(normalize_map[qRed(data[x])],
                                normalize_map[qGreen(data[x])],
                                normalize_map[qBlue(data[x])],
                                qAlpha(data[x]));
            }
        }
    }
    else{ // PsudeoClass
        int colors = img.numColors();
        unsigned int *cTable = img.colorTable();
        for(i=0; i < colors; ++i){
            cTable[i] = qRgba(normalize_map[qRed(cTable[i])],
                              normalize_map[qGreen(cTable[i])],
                              normalize_map[qBlue(cTable[i])],
                              qAlpha(cTable[i]));
        }
    }
    free(histogram);
    free(normalize_map);
}


void OImageEffect::equalize(QImage &img)
{
    int *histogram, *map, *equalize_map;
    int x, y, i, j;

    unsigned int high, low;

    // allocate histogram and maps
    histogram = (int *)calloc(MaxRGB+1, sizeof(int));
    map = (int *)malloc((MaxRGB+1)*sizeof(unsigned int));
    equalize_map  = (int *)malloc((MaxRGB+1)*sizeof(unsigned int));

    if(!histogram || !map || !equalize_map){
        owarn << "Unable to allocate equalize histogram and maps" << oendl;
        free(histogram);
        free(map);
        free(equalize_map);
        return;
    }
    // form histogram
    if(img.depth() > 8){ // DirectClass
        unsigned int *data;
        for(y=0; y < img.height(); ++y){
            data = (unsigned int *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                histogram[intensityValue(data[x])]++;
            }
        }
    }
    else{ // PsudeoClass
        unsigned char *data;
        unsigned int *cTable = img.colorTable();
        for(y=0; y < img.height(); ++y){
            data = (unsigned char *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                histogram[intensityValue(*(cTable+data[x]))]++;
            }
        }
    }

    // integrate the histogram to get the equalization map.
    j=0;
    for(i=0; i <= MaxRGB; i++){
        j+=histogram[i];
        map[i]=j;
    }
    free(histogram);
    if(map[MaxRGB] == 0){
        free(equalize_map);
        free(map);
        return;
    }
    // equalize
    low=map[0];
    high=map[MaxRGB];
    for(i=0; i <= MaxRGB; i++)
        equalize_map[i]=(unsigned int)
            ((((double) (map[i]-low))*MaxRGB)/QMAX(high-low,1));
    free(map);
    // stretch the histogram
    if(img.depth() > 8){ // DirectClass
        unsigned int *data;
        for(y=0; y < img.height(); ++y){
            data = (unsigned int *)img.scanLine(y);
            for(x=0; x < img.width(); ++x){
                data[x] = qRgba(equalize_map[qRed(data[x])],
                                equalize_map[qGreen(data[x])],
                                equalize_map[qBlue(data[x])],
                                qAlpha(data[x]));
            }
        }
    }
    else{ // PsudeoClass
        int colors = img.numColors();
        unsigned int *cTable = img.colorTable();
        for(i=0; i < colors; ++i){
            cTable[i] = qRgba(equalize_map[qRed(cTable[i])],
                              equalize_map[qGreen(cTable[i])],
                              equalize_map[qBlue(cTable[i])],
                              qAlpha(cTable[i]));
        }
    }
    free(equalize_map);
}

QImage OImageEffect::sample(QImage &src, int w, int h)
{
    if(w == src.width() && h == src.height())
        return(src);

    double *x_offset, *y_offset;
    int j, k, y;
    register int x;
    QImage dest(w, h, src.depth());

    x_offset = (double *)malloc(w*sizeof(double));
    y_offset = (double *)malloc(h*sizeof(double));
    if(!x_offset || !y_offset){
        owarn << "Unable to allocate pixels buffer" << oendl;
        free(x_offset);
        free(y_offset);
        return(src);
    }

    // init pixel offsets
    for(x=0; x < w; ++x)
        x_offset[x] = x*src.width()/((double)w);
    for(y=0; y < h; ++y)
        y_offset[y] = y*src.height()/((double)h);

    // sample each row
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *srcData, *destData;
        unsigned int *pixels;
        pixels = (unsigned int *)malloc(src.width()*sizeof(unsigned int));
        if(!pixels){
            owarn << "Unable to allocate pixels buffer" << oendl;
            free(pixels);
            free(x_offset);
            free(y_offset);
            return(src);
        }
        j = (-1);
        for(y=0; y < h; ++y){
            destData = (unsigned int *)dest.scanLine(y);
            if(j != y_offset[y]){
                // read a scan line
                j = (int)(y_offset[y]);
                srcData = (unsigned int *)src.scanLine(j);
                (void)memcpy(pixels, srcData, src.width()*sizeof(unsigned int));
            }
            // sample each column
            for(x=0; x < w; ++x){
                k = (int)(x_offset[x]);
                destData[x] = pixels[k];
            }
        }
        free(pixels);
    }
    else{ // PsudeoClass source image
        unsigned char *srcData, *destData;
        unsigned char *pixels;
        pixels = (unsigned char *)malloc(src.width()*sizeof(unsigned char));
        if(!pixels){
            owarn << "Unable to allocate pixels buffer" << oendl;
            free(pixels);
            free(x_offset);
            free(y_offset);
            return(src);
        }
        // copy colortable
        dest.setNumColors(src.numColors());
        (void)memcpy(dest.colorTable(), src.colorTable(),
                     src.numColors()*sizeof(unsigned int));

        // sample image
        j = (-1);
        for(y=0; y < h; ++y){
            destData = (unsigned char *)dest.scanLine(y);
            if(j != y_offset[y]){
                // read a scan line
                j = (int)(y_offset[y]);
                srcData = (unsigned char *)src.scanLine(j);
                (void)memcpy(pixels, srcData, src.width()*sizeof(unsigned char));
            }
            // sample each column
            for(x=0; x < w; ++x){
                k = (int)(x_offset[x]);
                destData[x] = pixels[k];
            }
        }
        free(pixels);
    }
    free(x_offset);
    free(y_offset);
    return(dest);
}

void OImageEffect::threshold(QImage &img, unsigned int threshold)
{
    int i, count;
    unsigned int *data;
    if(img.depth() > 8){ // DirectClass
        count = img.width()*img.height();
        data = (unsigned int *)img.bits();
    }
    else{ // PsudeoClass
        count = img.numColors();
        data = (unsigned int *)img.colorTable();
    }
    for(i=0; i < count; ++i)
        data[i] = intensityValue(data[i]) < threshold ? Qt::black.rgb() : Qt::white.rgb();
}

QImage OImageEffect::charcoal(QImage &src, double factor)
{
    QImage dest(src);
    dest.detach();
    toGray(dest);
    dest = edge(dest, factor);
    dest = blur(dest, factor);
    normalize(dest);
    dest.invertPixels(false);
    return(dest);
}

void OImageEffect::hull(const int x_offset, const int y_offset,
                        const int polarity, const int columns,
                        const int rows,
                        unsigned int *f, unsigned int *g)
{
    int x, y;

    unsigned int *p, *q, *r, *s;
    unsigned int v;
    if(f == NULL || g == NULL)
        return;
    p=f+(columns+2);
    q=g+(columns+2);
    r=p+(y_offset*(columns+2)+x_offset);
    for (y=0; y < rows; y++){
        p++;
        q++;
        r++;
        if(polarity > 0)
            for (x=0; x < columns; x++){
                v=(*p);
                if (*r > v)
                    v++;
                *q=v;
                p++;
                q++;
                r++;
            }
        else
            for(x=0; x < columns; x++){
                v=(*p);
                if (v > (unsigned int) (*r+1))
                    v--;
                *q=v;
                p++;
                q++;
                r++;
            }
        p++;
        q++;
        r++;
    }
    p=f+(columns+2);
    q=g+(columns+2);
    r=q+(y_offset*(columns+2)+x_offset);
    s=q-(y_offset*(columns+2)+x_offset);
    for(y=0; y < rows; y++){
        p++;
        q++;
        r++;
        s++;
        if(polarity > 0)
            for(x=0; x < (int) columns; x++){
                v=(*q);
                if (((unsigned int) (*s+1) > v) && (*r > v))
                    v++;
                *p=v;
                p++;
                q++;
                r++;
                s++;
            }
        else
            for (x=0; x < columns; x++){
                v=(*q);
                if (((unsigned int) (*s+1) < v) && (*r < v))
                    v--;
                *p=v;
                p++;
                q++;
                r++;
                s++;
            }
        p++;
        q++;
        r++;
        s++;
    }
}

QImage OImageEffect::despeckle(QImage &src)
{
    int i, j, x, y;
    unsigned int *blue_channel, *red_channel, *green_channel, *buffer,
        *alpha_channel;
    int packets;
    static const int
    X[4]= {0, 1, 1,-1},
    Y[4]= {1, 0, 1, 1};

    unsigned int *destData;
    QImage dest(src.width(), src.height(), 32);

    packets = (src.width()+2)*(src.height()+2);
    red_channel = (unsigned int *)calloc(packets, sizeof(unsigned int));
    green_channel = (unsigned int *)calloc(packets, sizeof(unsigned int));
    blue_channel = (unsigned int *)calloc(packets, sizeof(unsigned int));
    alpha_channel = (unsigned int *)calloc(packets, sizeof(unsigned int));
    buffer = (unsigned int *)calloc(packets, sizeof(unsigned int));
    if(!red_channel || ! green_channel || ! blue_channel || ! alpha_channel ||
       !buffer){
        free(red_channel);
        free(green_channel);
        free(blue_channel);
        free(alpha_channel);
        free(buffer);
        return(src);
    }

    // copy image pixels to color component buffers
    j = src.width()+2;
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *srcData;
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned int *)src.scanLine(y);
            ++j;
            for(x=0; x < src.width(); ++x){
                red_channel[j] = qRed(srcData[x]);
                green_channel[j] = qGreen(srcData[x]);
                blue_channel[j] = qBlue(srcData[x]);
                alpha_channel[j] = qAlpha(srcData[x]);
                ++j;
            }
            ++j;
        }
    }
    else{ // PsudeoClass source image
        unsigned char *srcData;
        unsigned int *cTable = src.colorTable();
        unsigned int pixel;
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned char *)src.scanLine(y);
            ++j;
            for(x=0; x < src.width(); ++x){
                pixel = *(cTable+srcData[x]);
                red_channel[j] = qRed(pixel);
                green_channel[j] = qGreen(pixel);
                blue_channel[j] = qBlue(pixel);
                alpha_channel[j] = qAlpha(pixel);
                ++j;
            }
            ++j;
        }
    }
    // reduce speckle in red channel
    for(i=0; i < 4; i++){
        hull(X[i],Y[i],1,src.width(),src.height(),red_channel,buffer);
        hull(-X[i],-Y[i],1,src.width(),src.height(),red_channel,buffer);
        hull(-X[i],-Y[i],-1,src.width(),src.height(),red_channel,buffer);
        hull(X[i],Y[i],-1,src.width(),src.height(),red_channel,buffer);
    }
    // reduce speckle in green channel
    for (i=0; i < packets; i++)
        buffer[i]=0;
    for (i=0; i < 4; i++){
        hull(X[i],Y[i],1,src.width(),src.height(),green_channel,buffer);
        hull(-X[i],-Y[i],1,src.width(),src.height(),green_channel,buffer);
        hull(-X[i],-Y[i],-1,src.width(),src.height(),green_channel,buffer);
        hull(X[i],Y[i],-1,src.width(),src.height(),green_channel,buffer);
    }
    // reduce speckle in blue channel
    for (i=0; i < packets; i++)
        buffer[i]=0;
    for (i=0; i < 4; i++){
        hull(X[i],Y[i],1,src.width(),src.height(),blue_channel,buffer);
        hull(-X[i],-Y[i],1,src.width(),src.height(),blue_channel,buffer);
        hull(-X[i],-Y[i],-1,src.width(),src.height(),blue_channel,buffer);
        hull(X[i],Y[i],-1,src.width(),src.height(),blue_channel,buffer);
    }
    // copy color component buffers to despeckled image
    j = dest.width()+2;
    for(y=0; y < dest.height(); ++y)
    {
        destData = (unsigned int *)dest.scanLine(y);
        ++j;
        for (x=0; x < dest.width(); ++x)
        {
            destData[x] = qRgba(red_channel[j], green_channel[j],
                                blue_channel[j], alpha_channel[j]);
            ++j;
        }
        ++j;
    }
    free(buffer);
    free(red_channel);
    free(green_channel);
    free(blue_channel);
    free(alpha_channel);
    return(dest);
}

unsigned int OImageEffect::generateNoise(unsigned int pixel,
                                         NoiseType noise_type)
{
#define NoiseEpsilon  1.0e-5
#define NoiseMask  0x7fff
#define SigmaUniform  4.0
#define SigmaGaussian  4.0
#define SigmaImpulse  0.10
#define SigmaLaplacian 10.0
#define SigmaMultiplicativeGaussian  0.5
#define SigmaPoisson  0.05
#define TauGaussian  20.0

    double alpha, beta, sigma, value;
    alpha=(double) (rand() & NoiseMask)/NoiseMask;
    if (alpha == 0.0)
        alpha=1.0;
    switch(noise_type){
    case UniformNoise:
    default:
        {
            value=(double) pixel+SigmaUniform*(alpha-0.5);
            break;
        }
    case GaussianNoise:
        {
            double tau;

            beta=(double) (rand() & NoiseMask)/NoiseMask;
            sigma=sqrt(-2.0*log(alpha))*cos(2.0*M_PI*beta);
            tau=sqrt(-2.0*log(alpha))*sin(2.0*M_PI*beta);
            value=(double) pixel+
                (sqrt((double) pixel)*SigmaGaussian*sigma)+(TauGaussian*tau);
            break;
        }
    case MultiplicativeGaussianNoise:
        {
            if (alpha <= NoiseEpsilon)
                sigma=MaxRGB;
            else
                sigma=sqrt(-2.0*log(alpha));
            beta=(rand() & NoiseMask)/NoiseMask;
            value=(double) pixel+
                pixel*SigmaMultiplicativeGaussian*sigma*cos(2.0*M_PI*beta);
            break;
        }
    case ImpulseNoise:
        {
            if (alpha < (SigmaImpulse/2.0))
                value=0;
            else
                if (alpha >= (1.0-(SigmaImpulse/2.0)))
                    value=MaxRGB;
                else
                    value=pixel;
            break;
        }
    case LaplacianNoise:
        {
            if (alpha <= 0.5)
            {
                if (alpha <= NoiseEpsilon)
                    value=(double) pixel-MaxRGB;
                else
                    value=(double) pixel+SigmaLaplacian*log(2.0*alpha);
                break;
            }
            beta=1.0-alpha;
            if (beta <= (0.5*NoiseEpsilon))
                value=(double) pixel+MaxRGB;
            else
                value=(double) pixel-SigmaLaplacian*log(2.0*beta);
            break;
        }
    case PoissonNoise:
        {
            register int
                i;

            for (i=0; alpha > exp(-SigmaPoisson*pixel); i++)
            {
                beta=(double) (rand() & NoiseMask)/NoiseMask;
                alpha=alpha*beta;
            }
            value=i/SigmaPoisson;
            break;
        }
    }
    if(value < 0.0)
        return(0);
    if(value > MaxRGB)
        return(MaxRGB);
    return((unsigned int) (value+0.5));
}

QImage OImageEffect::addNoise(QImage &src, NoiseType noise_type)
{
    int x, y;
    QImage dest(src.width(), src.height(), 32);
    unsigned int *destData;

    if(src.depth() > 8){ // DirectClass source image
        unsigned int *srcData;
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned int *)src.scanLine(y);
            destData = (unsigned int *)dest.scanLine(y);
            for(x=0; x < src.width(); ++x){
                destData[x] = qRgba(generateNoise(qRed(srcData[x]), noise_type),
                                    generateNoise(qGreen(srcData[x]), noise_type),
                                    generateNoise(qBlue(srcData[x]), noise_type),
                                    qAlpha(srcData[x]));
            }
        }
    }
    else{ // PsudeoClass source image
        unsigned char *srcData;
        unsigned int *cTable = src.colorTable();
        unsigned int pixel;
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned char *)src.scanLine(y);
            destData = (unsigned int *)dest.scanLine(y);
            for(x=0; x < src.width(); ++x){
                pixel = *(cTable+srcData[x]);
                destData[x] = qRgba(generateNoise(qRed(pixel), noise_type),
                                    generateNoise(qGreen(pixel), noise_type),
                                    generateNoise(qBlue(pixel), noise_type),
                                    qAlpha(pixel));
            }
        }

    }
    return(dest);
}

unsigned int OImageEffect::interpolateColor(QImage *image, double x_offset,
                                            double y_offset,
                                            unsigned int background)
{
    double alpha, beta;
    unsigned int p, q, r, s;
    int x, y;

    x = (int)x_offset;
    y = (int)y_offset;
    if((x < -1) || (x >= image->width()) || (y < -1) || (y >= image->height()))
        return(background);
    if(image->depth() > 8){
        if((x >= 0) && (y >= 0) && (x < (image->width()-1)) && (y < (image->height()-1)))    {
            unsigned int *t = (unsigned int *)image->scanLine(y);
            p = t[x];
            q = t[x+1];
            r = t[x+image->width()];
            s = t[x+image->width()+1];
        }
        else{
            unsigned int *t = (unsigned int *)image->scanLine(y);
            p = background;
            if((x >= 0) && (y >= 0)){
                p = t[x];
            }
            q = background;
            if(((x+1) < image->width()) && (y >= 0)){
                q = t[x+1];
            }
            r = background;
            if((x >= 0) && ((y+1) < image->height())){
                t = (unsigned int *)image->scanLine(y+1);
                r = t[x+image->width()];
            }
            s = background;
            if(((x+1) < image->width()) && ((y+1) < image->height())){
                t = (unsigned int *)image->scanLine(y+1);
                s = t[x+image->width()+1];
            }

        }
    }
    else{
        unsigned int *colorTable = (unsigned int *)image->colorTable();
        if((x >= 0) && (y >= 0) && (x < (image->width()-1)) && (y < (image->height()-1)))    {
            unsigned char *t;
            t = (unsigned char *)image->scanLine(y);
            p = *(colorTable+t[x]);
            q = *(colorTable+t[x+1]);
            t = (unsigned char *)image->scanLine(y+1);
            r = *(colorTable+t[x]);
            s = *(colorTable+t[x+1]);
        }
        else{
            unsigned char *t;
            p = background;
            if((x >= 0) && (y >= 0)){
                t = (unsigned char *)image->scanLine(y);
                p = *(colorTable+t[x]);
            }
            q = background;
            if(((x+1) < image->width()) && (y >= 0)){
                t = (unsigned char *)image->scanLine(y);
                q = *(colorTable+t[x+1]);
            }
            r = background;
            if((x >= 0) && ((y+1) < image->height())){
                t = (unsigned char *)image->scanLine(y+1);
                r = *(colorTable+t[x]);
            }
            s = background;
            if(((x+1) < image->width()) && ((y+1) < image->height())){
                t = (unsigned char *)image->scanLine(y+1);
                s = *(colorTable+t[x+1]);
            }

        }

    }
    x_offset -= floor(x_offset);
    y_offset -= floor(y_offset);
    alpha = 1.0-x_offset;
    beta = 1.0-y_offset;

    return(qRgba((unsigned char)(beta*(alpha*qRed(p)+x_offset*qRed(q))+y_offset*(alpha*qRed(r)+x_offset*qRed(s))),
                 (unsigned char)(beta*(alpha*qGreen(p)+x_offset*qGreen(q))+y_offset*(alpha*qGreen(r)+x_offset*qGreen(s))),
                 (unsigned char)(beta*(alpha*qBlue(p)+x_offset*qBlue(q))+y_offset*(alpha*qBlue(r)+x_offset*qBlue(s))),
                 (unsigned char)(beta*(alpha*qAlpha(p)+x_offset*qAlpha(q))+y_offset*(alpha*qAlpha(r)+x_offset*qAlpha(s)))));
}

QImage OImageEffect::implode(QImage &src, double factor,
                             unsigned int background)
{
    double amount, distance, radius;
    double x_center, x_distance, x_scale;
    double y_center, y_distance, y_scale;
    unsigned int *destData;
    int x, y;

    QImage dest(src.width(), src.height(), 32);

    // compute scaling factor
    x_scale = 1.0;
    y_scale = 1.0;
    x_center = (double)0.5*src.width();
    y_center = (double)0.5*src.height();
    radius=x_center;
    if(src.width() > src.height())
        y_scale = (double)src.width()/src.height();
    else if(src.width() < src.height()){
        x_scale = (double) src.height()/src.width();
        radius = y_center;
    }
    amount=factor/10.0;
    if(amount >= 0)
        amount/=10.0;
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *srcData;
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned int *)src.scanLine(y);
            destData = (unsigned int *)dest.scanLine(y);
            y_distance=y_scale*(y-y_center);
            for(x=0; x < src.width(); ++x){
                destData[x] = srcData[x];
                x_distance = x_scale*(x-x_center);
                distance= x_distance*x_distance+y_distance*y_distance;
                if(distance < (radius*radius)){
                    double factor;
                    // Implode the pixel.
                    factor=1.0;
                    if(distance > 0.0)
                        factor=
                            pow(sin(0.5000000000000001*M_PI*sqrt(distance)/radius),-amount);
                    destData[x] = interpolateColor(&src, factor*x_distance/x_scale+x_center,
                                                   factor*y_distance/y_scale+y_center,
                                                   background);
                }
            }
        }
    }
    else{ // PsudeoClass source image
        unsigned char *srcData;
        unsigned char idx;
        unsigned int *cTable = src.colorTable();
        for(y=0; y < src.height(); ++y){
            srcData = (unsigned char *)src.scanLine(y);
            destData = (unsigned int *)dest.scanLine(y);
            y_distance=y_scale*(y-y_center);
            for(x=0; x < src.width(); ++x){
                idx = srcData[x];
                destData[x] = cTable[idx];
                x_distance = x_scale*(x-x_center);
                distance= x_distance*x_distance+y_distance*y_distance;
                if(distance < (radius*radius)){
                    double factor;
                    // Implode the pixel.
                    factor=1.0;
                    if(distance > 0.0)
                        factor=
                            pow(sin(0.5000000000000001*M_PI*sqrt(distance)/radius),-amount);
                    destData[x] = interpolateColor(&src, factor*x_distance/x_scale+x_center,
                                                   factor*y_distance/y_scale+y_center,
                                                   background);
                }
            }
        }

    }
    return(dest);
}

QImage OImageEffect::rotate(QImage &img, RotateDirection r)
{
    QImage dest;
    int x, y;
    if(img.depth() > 8){
        unsigned int *srcData, *destData;
        switch(r){
        case Rotate90:
            dest.create(img.height(), img.width(), img.depth());
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned int *)img.scanLine(y);
                for(x=0; x < img.width(); ++x){
                    destData = (unsigned int *)dest.scanLine(x);
                    destData[img.height()-y-1] = srcData[x];
                }
            }
            break;
        case Rotate180:
            dest.create(img.width(), img.height(), img.depth());
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned int *)img.scanLine(y);
                destData = (unsigned int *)dest.scanLine(img.height()-y-1);
                for(x=0; x < img.width(); ++x)
                    destData[img.width()-x-1] = srcData[x];
            }
            break;
        case Rotate270:
            dest.create(img.height(), img.width(), img.depth());
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned int *)img.scanLine(y);
                for(x=0; x < img.width(); ++x){
                    destData = (unsigned int *)dest.scanLine(img.width()-x-1);
                    destData[y] = srcData[x];
                }
            }
            break;
        default:
            dest = img;
            break;
        }
    }
    else{
        unsigned char *srcData, *destData;
        unsigned int *srcTable, *destTable;
        switch(r){
        case Rotate90:
            dest.create(img.height(), img.width(), img.depth());
            dest.setNumColors(img.numColors());
            srcTable = (unsigned int *)img.colorTable();
            destTable = (unsigned int *)dest.colorTable();
            for(x=0; x < img.numColors(); ++x)
                destTable[x] = srcTable[x];
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned char *)img.scanLine(y);
                for(x=0; x < img.width(); ++x){
                    destData = (unsigned char *)dest.scanLine(x);
                    destData[img.height()-y-1] = srcData[x];
                }
            }
            break;
        case Rotate180:
            dest.create(img.width(), img.height(), img.depth());
            dest.setNumColors(img.numColors());
            srcTable = (unsigned int *)img.colorTable();
            destTable = (unsigned int *)dest.colorTable();
            for(x=0; x < img.numColors(); ++x)
                destTable[x] = srcTable[x];
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned char *)img.scanLine(y);
                destData = (unsigned char *)dest.scanLine(img.height()-y-1);
                for(x=0; x < img.width(); ++x)
                    destData[img.width()-x-1] = srcData[x];
            }
            break;
        case Rotate270:
            dest.create(img.height(), img.width(), img.depth());
            dest.setNumColors(img.numColors());
            srcTable = (unsigned int *)img.colorTable();
            destTable = (unsigned int *)dest.colorTable();
            for(x=0; x < img.numColors(); ++x)
                destTable[x] = srcTable[x];
            for(y=0; y < img.height(); ++y){
                srcData = (unsigned char *)img.scanLine(y);
                for(x=0; x < img.width(); ++x){
                    destData = (unsigned char *)dest.scanLine(img.width()-x-1);
                    destData[y] = srcData[x];
                }
            }
            break;
        default:
            dest = img;
            break;
        }

    }
    return(dest);
}

void OImageEffect::solarize(QImage &img, double factor)
{
    int i, count;
    int threshold;
    unsigned int *data;

    threshold = (int)(factor*(MaxRGB+1)/100.0);
    if(img.depth() < 32){
        data = (unsigned int *)img.colorTable();
        count = img.numColors();
    }
    else{
        data = (unsigned int *)img.bits();
        count = img.width()*img.height();
    }
    for(i=0; i < count; ++i){
        data[i] = qRgba(qRed(data[i]) > threshold ? MaxRGB-qRed(data[i]) : qRed(data[i]),
                        qGreen(data[i]) > threshold ? MaxRGB-qGreen(data[i]) : qGreen(data[i]),
                        qBlue(data[i]) > threshold ? MaxRGB-qBlue(data[i]) : qBlue(data[i]),
                        qAlpha(data[i]));
    }
}

QImage OImageEffect::spread(QImage &src, unsigned int amount)
{
    int quantum, x, y;
    int x_distance, y_distance;
    if(src.width() < 3 || src.height() < 3)
        return(src);
    QImage dest(src);
    dest.detach();
    quantum=(amount+1) >> 1;
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *q;
        for(y=0; y < src.height(); y++){
            q = (unsigned int *)dest.scanLine(y);
            for(x=0; x < src.width(); x++){
                x_distance = x + ((rand() & (amount+1))-quantum);
                y_distance = y + ((rand() & (amount+1))-quantum);
                x_distance = QMIN(x_distance, src.width()-1);
                y_distance = QMIN(y_distance, src.height()-1);
                if(x_distance < 0)
                    x_distance = 0;
                if(y_distance < 0)
                    y_distance = 0;
                p = (unsigned int *)src.scanLine(y_distance);
                p += x_distance;
                *q++=(*p);
            }
        }
    }
    else{ // PsudeoClass source image
        // just do colortable values
        unsigned char *p, *q;
        for(y=0; y < src.height(); y++){
            q = (unsigned char *)dest.scanLine(y);
            for(x=0; x < src.width(); x++){
                x_distance = x + ((rand() & (amount+1))-quantum);
                y_distance = y + ((rand() & (amount+1))-quantum);
                x_distance = QMIN(x_distance, src.width()-1);
                y_distance = QMIN(y_distance, src.height()-1);
                if(x_distance < 0)
                    x_distance = 0;
                if(y_distance < 0)
                    y_distance = 0;
                p = (unsigned char *)src.scanLine(y_distance);
                p += x_distance;
                *q++=(*p);
            }
        }
    }
    return(dest);
}

QImage OImageEffect::swirl(QImage &src, double degrees,
                           unsigned int background)
{
    double cosine, distance, factor, radius, sine, x_center, x_distance,
        x_scale, y_center, y_distance, y_scale;
    int x, y;
    unsigned int *q;
    QImage dest(src.width(), src.height(), 32);

    // compute scaling factor
    x_center = src.width()/2.0;
    y_center = src.height()/2.0;
    radius = QMAX(x_center,y_center);
    x_scale=1.0;
    y_scale=1.0;
    if(src.width() > src.height())
        y_scale=(double)src.width()/src.height();
    else if(src.width() < src.height())
        x_scale=(double)src.height()/src.width();
    degrees=DegreesToRadians(degrees);
    // swirl each row
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p;
        for(y=0; y < src.height(); y++){
            p = (unsigned int *)src.scanLine(y);
            q = (unsigned int *)dest.scanLine(y);
            y_distance = y_scale*(y-y_center);
            for(x=0; x < src.width(); x++){
                // determine if the pixel is within an ellipse
                *q=(*p);
                x_distance = x_scale*(x-x_center);
                distance = x_distance*x_distance+y_distance*y_distance;
                if (distance < (radius*radius)){
                    // swirl
                    factor = 1.0-sqrt(distance)/radius;
                    sine = sin(degrees*factor*factor);
                    cosine = cos(degrees*factor*factor);
                    *q = interpolateColor(&src,
                                          (cosine*x_distance-sine*y_distance)/x_scale+x_center,
                                          (sine*x_distance+cosine*y_distance)/y_scale+y_center,
                                          background);
                }
                p++;
                q++;
            }
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p;
        unsigned int *cTable = (unsigned int *)src.colorTable();
        for(y=0; y < src.height(); y++){
            p = (unsigned char *)src.scanLine(y);
            q = (unsigned int *)dest.scanLine(y);
            y_distance = y_scale*(y-y_center);
            for(x=0; x < src.width(); x++){
                // determine if the pixel is within an ellipse
                *q = *(cTable+(*p));
                x_distance = x_scale*(x-x_center);
                distance = x_distance*x_distance+y_distance*y_distance;
                if (distance < (radius*radius)){
                    // swirl
                    factor = 1.0-sqrt(distance)/radius;
                    sine = sin(degrees*factor*factor);
                    cosine = cos(degrees*factor*factor);
                    *q = interpolateColor(&src,
                                          (cosine*x_distance-sine*y_distance)/x_scale+x_center,
                                          (sine*x_distance+cosine*y_distance)/y_scale+y_center,
                                          background);
                }
                p++;
                q++;
            }
        }

    }
    return(dest);
}

QImage OImageEffect::wave(QImage &src, double amplitude, double wavelength,
                          unsigned int background)
{
    double *sine_map;
    int x, y;
    unsigned int *q;

    QImage dest(src.width(), src.height() + (int)(2*fabs(amplitude)), 32);
    // allocate sine map
    sine_map = (double *)malloc(dest.width()*sizeof(double));
    if(!sine_map)
        return(src);
    for(x=0; x < dest.width(); ++x)
        sine_map[x]=fabs(amplitude)+amplitude*sin((2*M_PI*x)/wavelength);
    // wave image
    for(y=0; y < dest.height(); ++y){
        q = (unsigned int *)dest.scanLine(y);
        for (x=0; x < dest.width(); x++){
            *q=interpolateColor(&src, x, (int)(y-sine_map[x]), background);
            ++q;
        }
    }
    free(sine_map);
    return(dest);
}

QImage OImageEffect::oilPaint(QImage &src, int radius)
{
    // TODO 8bpp src!
    if(src.depth() < 32){
        owarn << "Oil Paint source image < 32bpp. Convert before using!" << oendl;
        return(src);
    }
    int j, k, i, x, y;
    unsigned int *histogram;
    unsigned int *s;
    unsigned int count;

    unsigned int *srcData, *destData;

    QImage dest(src);
    dest.detach();
    histogram = (unsigned int *) malloc((MaxRGB+1)*sizeof(unsigned int));
    if(!histogram)
        return(src);
    // paint each row
    k=0;
    for(y = radius; y < src.height(); ++y){
        srcData = (unsigned int *)src.scanLine(y-radius);
        destData = (unsigned int *)dest.scanLine(y);
        srcData += radius*src.width()+radius;
        destData += radius;
        for(x=radius; x < src.width()-radius; ++x){
            // determine most frequent color
            count = 0;
            for(i=0; i < MaxRGB+1; ++i)
                histogram[i] = 0;
            for(i=0; i < radius; ++i){
                s = srcData-(radius-1)*src.width()-i-1;
                for(j =0; j < (2*i+1); ++j){
                    k = intensityValue(*s);
                    histogram[k]++;
                    if(histogram[k] > count){
                        *destData = *s;
                        count = histogram[k];
                    }
                    ++s;
                }
                s = srcData+(radius-i)*src.width()-i-1;
                for(j =0; j < (2*i+1); ++j){
                    k = intensityValue(*s);
                    histogram[k]++;
                    if(histogram[k] > count){
                        *destData = *s;
                        count = histogram[k];
                    }
                    ++s;
                }
            }
            s = srcData-radius;
            for(j =0; j < (2*i+1); ++j){
                k = intensityValue(*s);
                histogram[k]++;
                if(histogram[k] > count){
                    *destData = *s;
                    count = histogram[k];
                }
                ++s;
            }
            ++srcData;
            ++destData;
        }
    }
    free(histogram);
    return(dest);
}

//
// The following methods work by computing a value from neighboring pixels
// (mosfet 12/28/01)
//

QImage OImageEffect::edge(QImage &src, double factor)
{
#define Edge(weight) \
    total_red+=(weight)*qRed(*s); \
    total_green+=(weight)*qGreen(*s); \
    total_blue+=(weight)*qBlue(*s); \
    total_opacity+=(weight)*qAlpha(*s); \
    s++;

#define Edge256(weight) \
    total_red+=(weight)*qRed(*(cTable+(*s))); \
    total_green+=(weight)*qGreen(*(cTable+(*s))); \
    total_blue+=(weight)*qBlue(*(cTable+(*s))); \
    total_opacity+=(weight)*qAlpha(*(cTable+(*s))); \
    s++;

    if(src.width() < 3 || src.height() < 3)
        return(src);

    double total_blue, total_green, total_opacity, total_red, weight;

    int x, y;

    unsigned int *q;

    QImage dest(src.width(), src.height(), 32);
    weight=factor/8.0;
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *s;
        for(y=0; y < src.height(); ++y){
            p = (unsigned int *)src.scanLine(QMIN(QMAX(y-1,0),src.height()-3));
            q = (unsigned int *)dest.scanLine(y);
            // edge detect this row of pixels.
            *q++=(*(p+src.width()));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Edge(-weight/8); Edge(-weight/8) Edge(-weight/8);
                s=p+src.width();
                Edge(-weight/8); Edge(weight); Edge(-weight/8);
                s=p+2*src.width();
                Edge(-weight/8); Edge(-weight/8); Edge(-weight/8);
                *q = qRgba((unsigned char)((total_red < 0) ? 0 : (total_red > MaxRGB) ? MaxRGB : total_red),
                           (unsigned char)((total_green < 0) ? 0 : (total_green > MaxRGB) ? MaxRGB : total_green),
                           (unsigned char)((total_blue < 0) ? 0 : (total_blue > MaxRGB) ? MaxRGB : total_blue),
                           (unsigned char)((total_opacity < 0) ? 0 : (total_opacity > MaxRGB) ? MaxRGB : total_opacity));
                p++;
                q++;
            }
            p++;
            *q++=(*p);
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p, *p2, *p3, *s;
        unsigned int *cTable = src.colorTable();
        int scanLineIdx;
        for(y=0; y < src.height(); ++y){
            scanLineIdx = QMIN(QMAX(y-1,0),src.height()-3);
            p = (unsigned char *)src.scanLine(scanLineIdx);
            p2 = (unsigned char *)src.scanLine(scanLineIdx+1);
            p3 = (unsigned char *)src.scanLine(scanLineIdx+2);
            q = (unsigned int *)dest.scanLine(y);
            // edge detect this row of pixels.
            *q++=(*(cTable+(*p2)));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Edge256(-weight/8); Edge256(-weight/8) Edge256(-weight/8);
                s=p2;
                Edge256(-weight/8); Edge256(weight); Edge256(-weight/8);
                s=p3;
                Edge256(-weight/8); Edge256(-weight/8); Edge256(-weight/8);
                *q = qRgba((unsigned char)((total_red < 0) ? 0 : (total_red > MaxRGB) ? MaxRGB : total_red),
                           (unsigned char)((total_green < 0) ? 0 : (total_green > MaxRGB) ? MaxRGB : total_green),
                           (unsigned char)((total_blue < 0) ? 0 : (total_blue > MaxRGB) ? MaxRGB : total_blue),
                           (unsigned char)((total_opacity < 0) ? 0 : (total_opacity > MaxRGB) ? MaxRGB : total_opacity));
                p++;
                p2++;
                p3++;
                q++;
            }
            p++;
            *q++=(*(cTable+(*p)));
        }
    }
    return(dest);
}

QImage OImageEffect::sharpen(QImage &src, double factor)
{
#define Sharpen(weight) \
    total_red+=(weight)*qRed(*s); \
    total_green+=(weight)*qGreen(*s); \
    total_blue+=(weight)*qBlue(*s); \
    total_opacity+=(weight)*qAlpha(*s); \
    s++;

#define Sharpen256(weight) \
    total_red+=(weight)*qRed(*(cTable+(*s))); \
    total_green+=(weight)*qGreen(*(cTable+(*s))); \
    total_blue+=(weight)*qBlue(*(cTable+(*s))); \
    total_opacity+=(weight)*qAlpha(*(cTable+(*s))); \
    s++;

    if(src.width() < 3 || src.height() < 3)
        return(src);

    double total_blue, total_green, total_opacity, total_red;
    double quantum, weight;
    unsigned char r, g, b, a;

    int x, y;
    unsigned int *q;

    QImage dest(src.width(), src.height(), 32);
    weight = ((100.0-factor)/2.0+13.0);
    quantum = QMAX(weight-12.0, 1.0);
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *s;
        for(y=0; y < src.height(); ++y){
            p = (unsigned int *)src.scanLine(QMIN(QMAX(y-1,0),src.height()-3));
            q = (unsigned int *)dest.scanLine(y);
            // sharpen this row of pixels.
            *q++=(*(p+src.width()));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Sharpen(-1); Sharpen(-2); Sharpen(-1);
                s=p+src.width();
                Sharpen(-2); Sharpen(weight); Sharpen(-2);
                s=p+2*src.width();
                Sharpen(-1); Sharpen(-2); Sharpen(-1);
                if(total_red < 0)
                    r=0;
                else if(total_red > (int)(MaxRGB*quantum))
                    r = (unsigned char)MaxRGB;
                else
                    r = (unsigned char)((total_red+(quantum/2.0))/quantum);

                if(total_green < 0)
                    g = 0;
                else if(total_green > (int)(MaxRGB*quantum))
                    g = (unsigned char)MaxRGB;
                else
                    g = (unsigned char)((total_green+(quantum/2.0))/quantum);

                if(total_blue < 0)
                    b = 0;
                else if(total_blue > (int)(MaxRGB*quantum))
                    b = (unsigned char)MaxRGB;
                else
                    b = (unsigned char)((total_blue+(quantum/2.0))/quantum);

                if(total_opacity < 0)
                    a = 0;
                else if(total_opacity > (int)(MaxRGB*quantum))
                    a = (unsigned char)MaxRGB;
                else
                    a= (unsigned char)((total_opacity+(quantum/2.0))/quantum);

                *q = qRgba(r, g, b, a);

                p++;
                q++;
            }
            p++;
            *q++=(*p);
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p, *p2, *p3, *s;
        unsigned int *cTable = src.colorTable();
        int scanLineIdx;
        for(y=0; y < src.height(); ++y){
            scanLineIdx = QMIN(QMAX(y-1,0),src.height()-3);
            p = (unsigned char *)src.scanLine(scanLineIdx);
            p2 = (unsigned char *)src.scanLine(scanLineIdx+1);
            p3 = (unsigned char *)src.scanLine(scanLineIdx+2);
            q = (unsigned int *)dest.scanLine(y);
            // sharpen this row of pixels.
            *q++=(*(cTable+(*p2)));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Sharpen256(-1); Sharpen256(-2); Sharpen256(-1);
                s=p2;
                Sharpen256(-2); Sharpen256(weight); Sharpen256(-2);
                s=p3;
                Sharpen256(-1); Sharpen256(-2); Sharpen256(-1);
                if(total_red < 0)
                    r=0;
                else if(total_red > (int)(MaxRGB*quantum))
                    r = (unsigned char)MaxRGB;
                else
                    r = (unsigned char)((total_red+(quantum/2.0))/quantum);

                if(total_green < 0)
                    g = 0;
                else if(total_green > (int)(MaxRGB*quantum))
                    g = (unsigned char)MaxRGB;
                else
                    g = (unsigned char)((total_green+(quantum/2.0))/quantum);

                if(total_blue < 0)
                    b = 0;
                else if(total_blue > (int)(MaxRGB*quantum))
                    b = (unsigned char)MaxRGB;
                else
                    b = (unsigned char)((total_blue+(quantum/2.0))/quantum);

                if(total_opacity < 0)
                    a = 0;
                else if(total_opacity > (int)(MaxRGB*quantum))
                    a = (unsigned char)MaxRGB;
                else
                    a = (unsigned char)((total_opacity+(quantum/2.0))/quantum);

                *q = qRgba(r, g, b, a);

                p++;
                p2++;
                p3++;
                q++;
            }
            p++;
            *q++=(*(cTable+(*p)));
        }
    }
    return(dest);
}

QImage OImageEffect::emboss(QImage &src)
{
#define Emboss(weight) \
    total_red+=(weight)*qRed(*s); \
    total_green+=(weight)*qGreen(*s); \
    total_blue+=(weight)*qBlue(*s); \
    s++;

#define Emboss256(weight) \
    total_red+=(weight)*qRed(*(cTable+(*s))); \
    total_green+=(weight)*qGreen(*(cTable+(*s))); \
    total_blue+=(weight)*qBlue(*(cTable+(*s))); \
    s++;

    if(src.width() < 3 || src.height() < 3)
        return(src);

    double total_blue, total_green, total_red;
    int x, y;
    unsigned int *q;

    QImage dest(src.width(), src.height(), 32);
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *s;
        for(y=0; y < src.height(); ++y){
            p = (unsigned int *)src.scanLine(QMIN(QMAX(y-1,0),src.height()-3));
            q = (unsigned int *)dest.scanLine(y);
            // emboss this row of pixels.
            *q++=(*(p+src.width()));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                s=p;
                Emboss(-1); Emboss(-2); Emboss( 0);
                s=p+src.width();
                Emboss(-2); Emboss( 0); Emboss( 2);
                s=p+2*src.width();
                Emboss( 0); Emboss( 2); Emboss( 1);
                total_red += (MaxRGB+1)/2;
                total_green += (MaxRGB+1)/2;
                total_blue += (MaxRGB+1)/2;
                *q = qRgba((unsigned char)((total_red < 0) ? 0 : (total_red > MaxRGB) ? MaxRGB : total_red),
                           (unsigned char)((total_green < 0) ? 0 : (total_green > MaxRGB) ? MaxRGB : total_green),
                           (unsigned char)((total_blue < 0) ? 0 : (total_blue > MaxRGB) ? MaxRGB : total_blue),
                           255);
                p++;
                q++;
            }
            p++;
            *q++=(*p);
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p, *p2, *p3, *s;
        unsigned int *cTable = src.colorTable();
        int scanLineIdx;
        for(y=0; y < src.height(); ++y){
            scanLineIdx = QMIN(QMAX(y-1,0),src.height()-3);
            p = (unsigned char *)src.scanLine(scanLineIdx);
            p2 = (unsigned char *)src.scanLine(scanLineIdx+1);
            p3 = (unsigned char *)src.scanLine(scanLineIdx+2);
            q = (unsigned int *)dest.scanLine(y);
            // emboss this row of pixels.
            *q++=(*(cTable+(*p2)));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                s=p;
                Emboss256(-1); Emboss256(-2); Emboss256(0);
                s=p2;
                Emboss256(-2); Emboss256(0); Emboss256(2);
                s=p3;
                Emboss256(0); Emboss256(2); Emboss256(1);
                total_red += (MaxRGB+1)/2;
                total_green += (MaxRGB+1)/2;
                total_blue += (MaxRGB+1)/2;
                *q = qRgba((unsigned char)((total_red < 0) ? 0 : (total_red > MaxRGB) ? MaxRGB : total_red),
                           (unsigned char)((total_green < 0) ? 0 : (total_green > MaxRGB) ? MaxRGB : total_green),
                           (unsigned char)((total_blue < 0) ? 0 : (total_blue > MaxRGB) ? MaxRGB : total_blue),
                           255);
                p++;
                p2++;
                p3++;
                q++;
            }
            p++;
            *q++=(*(cTable+(*p)));
        }
    }
    toGray(dest);
    normalize(dest);
    return(dest);
}

QImage OImageEffect::shade(QImage &src, bool color_shading, double azimuth,
             double elevation)
{
    struct PointInfo{
        double x, y, z;
    };

    double distance, normal_distance, shade;
    int x, y;

    struct PointInfo light, normal;

    unsigned int *q;

    QImage dest(src.width(), src.height(), 32);

    azimuth = DegreesToRadians(azimuth);
    elevation = DegreesToRadians(elevation);
    light.x = MaxRGB*cos(azimuth)*cos(elevation);
    light.y = MaxRGB*sin(azimuth)*cos(elevation);
    light.z = MaxRGB*sin(elevation);
    normal.z= 2*MaxRGB;  // constant Z of surface normal

    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *s0, *s1, *s2;
        for(y=0; y < src.height(); ++y){
            p = (unsigned int *)src.scanLine(QMIN(QMAX(y-1,0),src.height()-3));
            q = (unsigned int *)dest.scanLine(y);
            // shade this row of pixels.
            *q++=(*(p+src.width()));
            p++;
            s0 = p;
            s1 = p + src.width();
            s2 = p + 2*src.width();
            for(x=1; x < src.width()-1; ++x){
                // determine the surface normal and compute shading.
                normal.x=intensityValue(*(s0-1))+intensityValue(*(s1-1))+intensityValue(*(s2-1))-
                    (double) intensityValue(*(s0+1))-(double) intensityValue(*(s1+1))-
                    (double) intensityValue(*(s2+1));
                normal.y=intensityValue(*(s2-1))+intensityValue(*s2)+intensityValue(*(s2+1))-
                    (double) intensityValue(*(s0-1))-(double) intensityValue(*s0)-
                    (double) intensityValue(*(s0+1));
                if((normal.x == 0) && (normal.y == 0))
                    shade=light.z;
                else{
                    shade=0.0;
                    distance=normal.x*light.x+normal.y*light.y+normal.z*light.z;
                    if (distance > 0.0){
                        normal_distance=
                            normal.x*normal.x+normal.y*normal.y+normal.z*normal.z;
                        if(fabs(normal_distance) > 0.0000001)
                            shade=distance/sqrt(normal_distance);
                    }
                }
                if(!color_shading){
                    *q = qRgba((unsigned char)(shade),
                               (unsigned char)(shade),
                               (unsigned char)(shade),
                               qAlpha(*s1));
                }
                else{
                    *q = qRgba((unsigned char)((shade*qRed(*s1))/(MaxRGB+1)),
                               (unsigned char)((shade*qGreen(*s1))/(MaxRGB+1)),
                               (unsigned char)((shade*qBlue(*s1))/(MaxRGB+1)),
                               qAlpha(*s1));
                }
                ++s0;
                ++s1;
                ++s2;
                q++;
            }
            *q++=(*s1);
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p, *s0, *s1, *s2;
        int scanLineIdx;
        unsigned int *cTable = (unsigned int *)src.colorTable();
        for(y=0; y < src.height(); ++y){
            scanLineIdx = QMIN(QMAX(y-1,0),src.height()-3);
            p = (unsigned char *)src.scanLine(scanLineIdx);
            q = (unsigned int *)dest.scanLine(y);
            // shade this row of pixels.
            s0 = p;
            s1 = (unsigned char *) src.scanLine(scanLineIdx+1);
            s2 = (unsigned char *) src.scanLine(scanLineIdx+2);
            *q++=(*(cTable+(*s1)));
            ++p;
            ++s0;
            ++s1;
            ++s2;
            for(x=1; x < src.width()-1; ++x){
                // determine the surface normal and compute shading.
                normal.x=intensityValue(*(cTable+(*(s0-1))))+intensityValue(*(cTable+(*(s1-1))))+intensityValue(*(cTable+(*(s2-1))))-
                    (double) intensityValue(*(cTable+(*(s0+1))))-(double) intensityValue(*(cTable+(*(s1+1))))-
                    (double) intensityValue(*(cTable+(*(s2+1))));
                normal.y=intensityValue(*(cTable+(*(s2-1))))+intensityValue(*(cTable+(*s2)))+intensityValue(*(cTable+(*(s2+1))))-
                    (double) intensityValue(*(cTable+(*(s0-1))))-(double) intensityValue(*(cTable+(*s0)))-
                    (double) intensityValue(*(cTable+(*(s0+1))));
                if((normal.x == 0) && (normal.y == 0))
                    shade=light.z;
                else{
                    shade=0.0;
                    distance=normal.x*light.x+normal.y*light.y+normal.z*light.z;
                    if (distance > 0.0){
                        normal_distance=
                            normal.x*normal.x+normal.y*normal.y+normal.z*normal.z;
                        if(fabs(normal_distance) > 0.0000001)
                            shade=distance/sqrt(normal_distance);
                    }
                }
                if(!color_shading){
                    *q = qRgba((unsigned char)(shade),
                               (unsigned char)(shade),
                               (unsigned char)(shade),
                               qAlpha(*(cTable+(*s1))));
                }
                else{
                    *q = qRgba((unsigned char)((shade*qRed(*(cTable+(*s1))))/(MaxRGB+1)),
                               (unsigned char)((shade*qGreen(*(cTable+(*s1))))/(MaxRGB+1)),
                               (unsigned char)((shade*qBlue(*(cTable+(*s1))))/(MaxRGB+1)),
                               qAlpha(*s1));
                }
                ++s0;
                ++s1;
                ++s2;
                q++;
            }
            *q++=(*(cTable+(*s1)));
        }
    }
    return(dest);
}

QImage OImageEffect::blur(QImage &src, double factor)
{

#define Blur(weight) \
    total_red+=(weight)*qRed(*s); \
    total_green+=(weight)*qGreen(*s); \
    total_blue+=(weight)*qBlue(*s); \
    total_opacity+=(weight)*qAlpha(*s); \
    s++;

#define Blur256(weight) \
    total_red+=(weight)*qRed(*(cTable+(*s))); \
    total_green+=(weight)*qGreen(*(cTable+(*s))); \
    total_blue+=(weight)*qBlue(*(cTable+(*s))); \
    total_opacity+=(weight)*qAlpha(*(cTable+(*s))); \
    s++;

    if(src.width() < 3 || src.height() < 3)
        return(src);

    double quantum, total_blue, total_green, total_opacity, total_red, weight;

    int x, y;
    unsigned int *q;

    QImage dest(src.width(), src.height(), 32);
    weight=((100.0-factor)/2)+1;
    quantum = QMAX(weight+12.0, 1.0);
    if(src.depth() > 8){ // DirectClass source image
        unsigned int *p, *s;
        for(y=0; y < src.height(); ++y){
            p = (unsigned int *)src.scanLine(QMIN(QMAX(y-1,0),src.height()-3));
            q = (unsigned int *)dest.scanLine(y);
            // blur this row of pixels.
            *q++=(*(p+src.width()));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Blur(1); Blur(2); Blur(1);
                s=p+src.width();
                Blur(2); Blur(weight); Blur(2);
                s=p+2*src.width();
                Blur(1); Blur(2); Blur(1);
                *q = qRgba((unsigned char)((total_red+(quantum/2))/quantum),
                           (unsigned char)((total_green+(quantum/2))/quantum),
                           (unsigned char)((total_blue+(quantum/2))/quantum),
                           (unsigned char)((total_opacity+(quantum/2))/quantum));
                p++;
                q++;
            }
            p++;
            *q++=(*p);
        }
    }
    else{ // PsudeoClass source image
        unsigned char *p, *p2, *p3, *s;
        unsigned int *cTable = src.colorTable();
        int scanLineIdx;
        for(y=0; y < src.height(); ++y){
            scanLineIdx = QMIN(QMAX(y-1,0),src.height()-3);
            p = (unsigned char *)src.scanLine(scanLineIdx);
            p2 = (unsigned char *)src.scanLine(scanLineIdx+1);
            p3 = (unsigned char *)src.scanLine(scanLineIdx+2);
            q = (unsigned int *)dest.scanLine(y);
            // blur this row of pixels.
            *q++=(*(cTable+(*p2)));
            for(x=1; x < src.width()-1; ++x){
                // compute weighted average of target pixel color components.
                total_red=0.0;
                total_green=0.0;
                total_blue=0.0;
                total_opacity=0.0;
                s=p;
                Blur256(1); Blur256(2); Blur256(1);
                s=p2;
                Blur256(2); Blur256(weight); Blur256(2);
                s=p3;
                Blur256(1); Blur256(2); Blur256(1);
                *q = qRgba((unsigned char)((total_red+(quantum/2))/quantum),
                           (unsigned char)((total_green+(quantum/2))/quantum),
                           (unsigned char)((total_blue+(quantum/2))/quantum),
                           (unsigned char)((total_opacity+(quantum/2))/quantum));
                p++;
                p2++;
                p3++;
                q++;
            }
            p++;
            *q++=(*(cTable+(*p)));
        }
    }
    return(dest);
}

// High quality, expensive HSV contrast. You can do a faster one by just
// taking a grayscale threshold (ie: 128) and incrementing RGB color
// channels above it and decrementing those below it, but this gives much
// better results. (mosfet 12/28/01)
void OImageEffect::contrastHSV(QImage &img, bool sharpen)
{
    int i, sign;
    unsigned int *data;
    int count;
    double brightness, scale, theta;
    QColor c;
    int h, s, v;

    sign = sharpen ? 1 : -1;
    scale=0.5000000000000001;
    if(img.depth() > 8){
        count = img.width()*img.height();
        data = (unsigned int *)img.bits();
    }
    else{
        count = img.numColors();
        data = (unsigned int *)img.colorTable();
    }
    for(i=0; i < count; ++i){
        c.setRgb(data[i]);
        c.hsv(&h, &s, &v);
        brightness = v/255.0;
        theta=(brightness-0.5)*M_PI;
        brightness+=scale*(((scale*((sin(theta)+1.0)))-brightness)*sign);
        if (brightness > 1.0)
            brightness=1.0;
        else
            if (brightness < 0)
                brightness=0.0;
        v = (int)(brightness*255);
        c.setHsv(h, s, v);
        data[i] = qRgba(c.red(), c.green(), c.blue(), qAlpha(data[i]));
    }
}



}
}

---