plfilterquantize.h

/*
/--------------------------------------------------------------------
|
|      $Id: plfilterquantize.h,v 1.4 2002/11/18 14:45:24 uzadow Exp $
|
|      Copyright (c) 1996-2002 Ulrich von Zadow
|
\--------------------------------------------------------------------
*/

#if !defined(INCL_PLFILTERQUANTIZE)
#define INCL_PLFILTERQUANTIZE

#if _MSC_VER >= 1000
#pragma once
#endif // _MSC_VER >= 1000

#include "plfilter.h"
#include "plbitmap.h"

#define PLDTHPAL_MEDIAN          0       // Median Cut
#define PLDTHPAL_POPULARITY      1       // Popularity Sort
#define PLDTHPAL_DEFAULT         2       // Use Default Palette
#define PLDTHPAL_USERDEFINED     3       // Use Palette set by SetUserPalette()

#define PLDTH_NONE      0       // None
#define PLDTH_ORDERED   1       // Ordered Dithering
#define PLDTH_FS        2       // Floyd-Steinberg Dithering
//#define PLDTH_JITTER    3       // Jitter preprocessing


//! Returns an 8 bpp bitmap containing a best-fit representation of the
//! source 32 bpp bitmap.
class PLFilterQuantize : public PLFilter
{
public:
  //! DitherPaletteType and DitherType determine the type of quantization:
  //!
  //! PLDTHPAL_MEDIAN (0): Median cut
  //!
  //! PLDTHPAL_POPULARITY (1): Popularity sort
  //!
  //! PLDTHPAL_DEFAULT (2): Use default palette
  //!
  //! PLDTHPAL_USERDEFINED (3): Use palette defined by SetUserPalette();
  //!
  //!
  //! PLDTH_NONE (0): No dithering
  //!
  //! PLDTH_ORDERED (1): Ordered dithering
  //!
  //! PLDTH_FS (2): Floyd-Steinberg dithering
  PLFilterQuantize (int DitherPaletteType, int DitherType);
  //!
  virtual ~PLFilterQuantize();

  //!
  virtual void Apply(PLBmp * pBmpSource, PLBmp * pBmpDest) const;

  //! For PLDTHPAL_USERDEFINED, sets the palette to use.
  void SetUserPalette(const PLPixel32* pPal);

  static const PLPixel32* GetDefaultPalette ();

private:
  // Local structs defining the quantization buffer
  typedef struct tagQUBOX
  {
    PLPixel32 Corner0, Corner1;
    PLPixel32 Average;
    PLULONG count;
  } QUBOX;

  typedef struct tagHISTONODE
  {
    int   index;
    PLULONG count;
  } HISTONODE;

  // Private members
  void initLUT();
  void deleteLUT();

  void genMedianPalette (PLBmp * pBmpSource, PLBmp * pBmpDest) const;
  void split (QUBOX * pBox0, QUBOX * pBox1, int ColComp) const;
  void squeeze(QUBOX * pBox) const;
  void genPopularityPalette (PLBmp * pBmpSource, PLBmp * pBmpDest) const;
  void genColorArray(PLBmp * pBmpSource) const;
  void genDefaultPalette (PLBmp * pBmpSource) const;
  void addColor(PLPixel32 col, PLULONG count) const;
  void makeBox(PLPixel32 col, int i, PLULONG c) const;
  int getColorTableIndex (PLPixel32 col) const;
  int getShiftedColorTableIndex (PLPixel32 col) const;

  void ditherDestBmp(PLBmp * pBmpSource, PLBmp * pBmpDest) const;
  void jitterPixel (int i, int y, PLPixel32 * pPixel) const;
  void ditherPixelOrdered (int x, int y, PLPixel32 * pPixel) const;
  void ditherCompOrdered (int x, int y, PLBYTE * pComp) const;
  void ditherPixelFS(double * pR, double * pG, double * pB, double * pCurErrors) const;
  void ditherCompFS (double * pComp, double Error) const;
  PLBYTE getNeighbor (PLPixel32 Color, PLPixel32 * pPal) const;
  int colorDist (PLPixel32 c0, PLPixel32 c1) const;

  int clip (int c) const;

  int m_DitherPaletteType;
  int m_DitherType;
  PLPixel32* m_pUserPal;

  HISTONODE ** m_ppHisto; // Array of 32x32x32 color bins. Allocated
                          // sparsely to save memory.
  QUBOX * m_pQuBoxes;     // Array of 256 boxes, one for each color.
};

inline int PLFilterQuantize::clip (int c) const
{
  if (c > 255)
    return 255;
  if (c < 0)
    return 0;
  return c;
}

#endif

/*
/--------------------------------------------------------------------
|
|      $Log: plfilterquantize.h,v $
|      Revision 1.4  2002/11/18 14:45:24  uzadow
|      Added PNG compression support, fixed docs.
|
|      Revision 1.3  2002/02/24 13:00:47  uzadow
|      Documentation update; removed buggy PLFilterRotate.
|
|      Revision 1.2  2001/10/06 22:03:26  uzadow
|      Added PL prefix to basic data types.
|
|      Revision 1.1  2001/09/16 19:03:23  uzadow
|      Added global name prefix PL, changed most filenames.
|
|      Revision 1.4  2001/09/15 20:39:57  uzadow
|      Added Quantization to user-defined palette (Andreas Köpf)
|
|      Revision 1.3  2001/01/15 15:05:31  uzadow
|      Added PLBmp::ApplyFilter() and PLBmp::CreateFilteredCopy()
|
|      Revision 1.2  2000/12/18 22:42:53  uzadow
|      Replaced RGBAPIXEL with PLPixel32.
|
|      Revision 1.1  2000/09/26 12:14:49  Administrator
|      Refactored quantization.
|
|
|
\--------------------------------------------------------------------
*/

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