dcmimage/include/dcmtk/dcmimage/diqtfs.h

/*
 *
 *  Copyright (C) 2002-2010, OFFIS e.V.
 *  All rights reserved.  See COPYRIGHT file for details.
 *
 *  This software and supporting documentation were developed by
 *
 *    OFFIS e.V.
 *    R&D Division Health
 *    Escherweg 2
 *    D-26121 Oldenburg, Germany
 *
 *
 *  Module:  dcmimage
 *
 *  Author:  Marco Eichelberg
 *
 *  Purpose: class DcmQuantFloydSteinberg
 *
 *  Last Update:      $Author: joergr $
 *  Update Date:      $Date: 2010-10-14 13:16:29 $
 *  CVS/RCS Revision: $Revision: 1.5 $
 *  Status:           $State: Exp $
 *
 *  CVS/RCS Log at end of file
 *
 */


#ifndef DIQTFS_H
#define DIQTFS_H


#include "dcmtk/config/osconfig.h"
#include "dcmtk/dcmimage/diqtpix.h"   /* for DcmQuantPixel */
#include "dcmtk/ofstd/ofcond.h"    /* for OFCondition */


#define DcmQuantFloydSteinbergScale 1024


class DcmQuantFloydSteinberg
{
public:

  DcmQuantFloydSteinberg();

  ~DcmQuantFloydSteinberg();

  OFCondition initialize(unsigned long cols);
  
  inline void adjust(DcmQuantPixel& px, long col, long maxval)
  {
    register long sr = px.getRed()   + thisrerr[col + 1] / DcmQuantFloydSteinbergScale;
    register long sg = px.getGreen() + thisgerr[col + 1] / DcmQuantFloydSteinbergScale;
    register long sb = px.getBlue()  + thisberr[col + 1] / DcmQuantFloydSteinbergScale;
    if ( sr < 0 ) sr = 0;
    else if ( sr > OFstatic_cast(long, maxval) ) sr = maxval;
    if ( sg < 0 ) sg = 0;
    else if ( sg > OFstatic_cast(long, maxval) ) sg = maxval;
    if ( sb < 0 ) sb = 0;
    else if ( sb > OFstatic_cast(long, maxval) ) sb = maxval;
    px.assign(OFstatic_cast(DcmQuantComponent, sr), OFstatic_cast(DcmQuantComponent, sg), OFstatic_cast(DcmQuantComponent, sb));
  }

  inline void propagate(const DcmQuantPixel& px, const DcmQuantPixel& mapped, long col)
  {
    register long err;

    /* Propagate Floyd-Steinberg error terms. */
    if ( fs_direction )
    {
        err = ( OFstatic_cast(long, px.getRed()) - OFstatic_cast(long, mapped.getRed()) ) * DcmQuantFloydSteinbergScale;
        thisrerr[col + 2] += ( err * 7 ) / 16;
        nextrerr[col    ] += ( err * 3 ) / 16;
        nextrerr[col + 1] += ( err * 5 ) / 16;
        nextrerr[col + 2] += ( err     ) / 16;
        err = ( OFstatic_cast(long, px.getGreen()) - OFstatic_cast(long, mapped.getGreen()) ) * DcmQuantFloydSteinbergScale;
        thisgerr[col + 2] += ( err * 7 ) / 16;
        nextgerr[col    ] += ( err * 3 ) / 16;
        nextgerr[col + 1] += ( err * 5 ) / 16;
        nextgerr[col + 2] += ( err     ) / 16;
        err = ( OFstatic_cast(long, px.getBlue()) - OFstatic_cast(long, mapped.getBlue()) ) * DcmQuantFloydSteinbergScale;
        thisberr[col + 2] += ( err * 7 ) / 16;
        nextberr[col    ] += ( err * 3 ) / 16;
        nextberr[col + 1] += ( err * 5 ) / 16;
        nextberr[col + 2] += ( err     ) / 16;
    }
    else
    {
        err = ( OFstatic_cast(long, px.getRed()) - OFstatic_cast(long, mapped.getRed()) ) * DcmQuantFloydSteinbergScale;
        thisrerr[col    ] += ( err * 7 ) / 16;
        nextrerr[col + 2] += ( err * 3 ) / 16;
        nextrerr[col + 1] += ( err * 5 ) / 16;
        nextrerr[col    ] += ( err     ) / 16;
        err = ( OFstatic_cast(long, px.getGreen()) - OFstatic_cast(long, mapped.getGreen()) ) * DcmQuantFloydSteinbergScale;
        thisgerr[col    ] += ( err * 7 ) / 16;
        nextgerr[col + 2] += ( err * 3 ) / 16;
        nextgerr[col + 1] += ( err * 5 ) / 16;
        nextgerr[col    ] += ( err     ) / 16;
        err = ( OFstatic_cast(long, px.getBlue()) - OFstatic_cast(long, mapped.getBlue()) ) * DcmQuantFloydSteinbergScale;
        thisberr[col    ] += ( err * 7 ) / 16;
        nextberr[col + 2] += ( err * 3 ) / 16;
        nextberr[col + 1] += ( err * 5 ) / 16;
        nextberr[col    ] += ( err     ) / 16;
    }
  }

  inline void startRow(long& col, long& limitcol)
  {
    for (unsigned long c = 0; c < columns + 2; ++c)
      nextrerr[c] = nextgerr[c] = nextberr[c] = 0;
  
    if (fs_direction)
    {
        col = 0;
        limitcol = columns;
    }
    else
    {
        col = columns - 1;
        limitcol = -1;
    }
  }
  
  inline void finishRow()
  {
    temperr = thisrerr;
    thisrerr = nextrerr;
    nextrerr = temperr;
    temperr = thisgerr;
    thisgerr = nextgerr;
    nextgerr = temperr;
    temperr = thisberr;
    thisberr = nextberr;
    nextberr = temperr;
    fs_direction = ! fs_direction;
  }

  inline void nextCol(long& col) const
  {
    if (fs_direction) ++col; else --col;
  }

private:

  void cleanup();

  DcmQuantFloydSteinberg(const DcmQuantFloydSteinberg& src);

  DcmQuantFloydSteinberg& operator=(const DcmQuantFloydSteinberg& src);

  long *thisrerr;

  long *nextrerr;
  
  long *thisgerr;

  long *nextgerr;

  long *thisberr;

  long *nextberr;

  long *temperr;

  int fs_direction;
  
  unsigned long columns;

};


#endif


/*
 * CVS/RCS Log:
 * $Log: diqtfs.h,v $
 * Revision 1.5  2010-10-14 13:16:29  joergr
 * Updated copyright header. Added reference to COPYRIGHT file.
 *
 * Revision 1.4  2005/12/08 16:01:46  meichel
 * Changed include path schema for all DCMTK header files
 *
 * Revision 1.3  2003/12/23 12:16:59  joergr
 * Adapted type casts to new-style typecast operators defined in ofcast.h.
 * Updated copyright header.
 *
 * Revision 1.2  2002/05/15 09:53:30  meichel
 * Minor corrections to avoid warnings on Sun CC 2.0.1
 *
 * Revision 1.1  2002/01/25 13:32:04  meichel
 * Initial release of new color quantization classes and
 *   the dcmquant tool in module dcmimage.
 *
 *
 */

---

Generated on 6 Jan 2011 for OFFIS DCMTK Version 3.6.0 by Doxygen 1.5.1