vcl/source/bitmap/BitmapMedianFilter.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  */
  10
  11 #include <vcl/bitmap.hxx>
  12 #include <vcl/bitmapex.hxx>
  13 #include <vcl/bitmapaccess.hxx>
  14 #include <vcl/BitmapMedianFilter.hxx>
  15
  16 #include <bitmapwriteaccess.hxx>
  17
  18 #define S2(a, b)                                                                                   \
  19     {                                                                                              \
  20         long t;                                                                                    \
  21         if ((t = b - a) < 0)                                                                       \
  22         {                                                                                          \
  23             a += t;                                                                                \
  24             b -= t;                                                                                \
  25         }                                                                                          \
  26     }
  27 #define MN3(a, b, c)                                                                               \
  28     S2(a, b);                                                                                      \
  29     S2(a, c);
  30 #define MX3(a, b, c)                                                                               \
  31     S2(b, c);                                                                                      \
  32     S2(a, c);
  33 #define MNMX3(a, b, c)                                                                             \
  34     MX3(a, b, c);                                                                                  \
  35     S2(a, b);
  36 #define MNMX4(a, b, c, d)                                                                          \
  37     S2(a, b);                                                                                      \
  38     S2(c, d);                                                                                      \
  39     S2(a, c);                                                                                      \
  40     S2(b, d);
  41 #define MNMX5(a, b, c, d, e)                                                                       \
  42     S2(a, b);                                                                                      \
  43     S2(c, d);                                                                                      \
  44     MN3(a, c, e);                                                                                  \
  45     MX3(b, d, e);
  46 #define MNMX6(a, b, c, d, e, f)                                                                    \
  47     S2(a, d);                                                                                      \
  48     S2(b, e);                                                                                      \
  49     S2(c, f);                                                                                      \
  50     MN3(a, b, c);                                                                                  \
  51     MX3(d, e, f);
  52
  53 BitmapEx BitmapMedianFilter::execute(BitmapEx const& rBitmapEx) const
  54 {
  55     Bitmap aBitmap(rBitmapEx.GetBitmap());
  56
  57     Bitmap::ScopedReadAccess pReadAcc(aBitmap);
  58     bool bRet = false;
  59
  60     if (pReadAcc)
  61     {
  62         Bitmap aNewBmp(aBitmap.GetSizePixel(), 24);
  63         BitmapScopedWriteAccess pWriteAcc(aNewBmp);
  64
  65         if (pWriteAcc)
  66         {
  67             const long nWidth = pWriteAcc->Width(), nWidth2 = nWidth + 2;
  68             const long nHeight = pWriteAcc->Height(), nHeight2 = nHeight + 2;
  69             std::unique_ptr<long[]> pColm(new long[nWidth2]);
  70             std::unique_ptr<long[]> pRows(new long[nHeight2]);
  71             std::unique_ptr<BitmapColor[]> pColRow1(new BitmapColor[nWidth2]);
  72             std::unique_ptr<BitmapColor[]> pColRow2(new BitmapColor[nWidth2]);
  73             std::unique_ptr<BitmapColor[]> pColRow3(new BitmapColor[nWidth2]);
  74             BitmapColor* pRowTmp1 = pColRow1.get();
  75             BitmapColor* pRowTmp2 = pColRow2.get();
  76             BitmapColor* pRowTmp3 = pColRow3.get();
  77             BitmapColor* pColor;
  78             long nY, nX, i;
  79             long nR1, nR2, nR3, nR4, nR5, nR6, nR7, nR8, nR9;
  80             long nG1, nG2, nG3, nG4, nG5, nG6, nG7, nG8, nG9;
  81             long nB1, nB2, nB3, nB4, nB5, nB6, nB7, nB8, nB9;
  82
  83             // create column LUT
  84             for (i = 0; i < nWidth2; i++)
  85                 pColm[i] = (i > 0) ? (i - 1) : 0;
  86
  87             pColm[nWidth + 1] = pColm[nWidth];
  88
  89             // create row LUT
  90             for (i = 0; i < nHeight2; i++)
  91                 pRows[i] = (i > 0) ? (i - 1) : 0;
  92
  93             pRows[nHeight + 1] = pRows[nHeight];
  94
  95             // read first three rows of bitmap color
  96             if (nHeight2 > 2)
  97             {
  98                 for (i = 0; i < nWidth2; i++)
  99                 {
 100                     pColRow1[i] = pReadAcc->GetColor(pRows[0], pColm[i]);
 101                     pColRow2[i] = pReadAcc->GetColor(pRows[1], pColm[i]);
 102                     pColRow3[i] = pReadAcc->GetColor(pRows[2], pColm[i]);
 103                 }
 104             }
 105
 106             // do median filtering
 107             for (nY = 0; nY < nHeight;)
 108             {
 109                 Scanline pScanline = pWriteAcc->GetScanline(nY);
 110                 for (nX = 0; nX < nWidth; nX++)
 111                 {
 112                     pColor = pRowTmp1 + nX;
 113                     nR1 = pColor->GetRed();
 114                     nG1 = pColor->GetGreen();
 115                     nB1 = pColor->GetBlue();
 116                     nR2 = (++pColor)->GetRed();
 117                     nG2 = pColor->GetGreen();
 118                     nB2 = pColor->GetBlue();
 119                     nR3 = (++pColor)->GetRed();
 120                     nG3 = pColor->GetGreen();
 121                     nB3 = pColor->GetBlue();
 122
 123                     pColor = pRowTmp2 + nX;
 124                     nR4 = pColor->GetRed();
 125                     nG4 = pColor->GetGreen();
 126                     nB4 = pColor->GetBlue();
 127                     nR5 = (++pColor)->GetRed();
 128                     nG5 = pColor->GetGreen();
 129                     nB5 = pColor->GetBlue();
 130                     nR6 = (++pColor)->GetRed();
 131                     nG6 = pColor->GetGreen();
 132                     nB6 = pColor->GetBlue();
 133
 134                     pColor = pRowTmp3 + nX;
 135                     nR7 = pColor->GetRed();
 136                     nG7 = pColor->GetGreen();
 137                     nB7 = pColor->GetBlue();
 138                     nR8 = (++pColor)->GetRed();
 139                     nG8 = pColor->GetGreen();
 140                     nB8 = pColor->GetBlue();
 141                     nR9 = (++pColor)->GetRed();
 142                     nG9 = pColor->GetGreen();
 143                     nB9 = pColor->GetBlue();
 144
 145                     MNMX6(nR1, nR2, nR3, nR4, nR5, nR6);
 146                     MNMX5(nR7, nR2, nR3, nR4, nR5);
 147                     MNMX4(nR8, nR2, nR3, nR4);
 148                     MNMX3(nR9, nR2, nR3);
 149
 150                     MNMX6(nG1, nG2, nG3, nG4, nG5, nG6);
 151                     MNMX5(nG7, nG2, nG3, nG4, nG5);
 152                     MNMX4(nG8, nG2, nG3, nG4);
 153                     MNMX3(nG9, nG2, nG3);
 154
 155                     MNMX6(nB1, nB2, nB3, nB4, nB5, nB6);
 156                     MNMX5(nB7, nB2, nB3, nB4, nB5);
 157                     MNMX4(nB8, nB2, nB3, nB4);
 158                     MNMX3(nB9, nB2, nB3);
 159
 160                     // set destination color
 161                     pWriteAcc->SetPixelOnData(pScanline, nX,
 162                                               BitmapColor(static_cast<sal_uInt8>(nR2),
 163                                                           static_cast<sal_uInt8>(nG2),
 164                                                           static_cast<sal_uInt8>(nB2)));
 165                 }
 166
 167                 if (++nY < nHeight)
 168                 {
 169                     if (pRowTmp1 == pColRow1.get())
 170                     {
 171                         pRowTmp1 = pColRow2.get();
 172                         pRowTmp2 = pColRow3.get();
 173                         pRowTmp3 = pColRow1.get();
 174                     }
 175                     else if (pRowTmp1 == pColRow2.get())
 176                     {
 177                         pRowTmp1 = pColRow3.get();
 178                         pRowTmp2 = pColRow1.get();
 179                         pRowTmp3 = pColRow2.get();
 180                     }
 181                     else
 182                     {
 183                         pRowTmp1 = pColRow1.get();
 184                         pRowTmp2 = pColRow2.get();
 185                         pRowTmp3 = pColRow3.get();
 186                     }
 187
 188                     for (i = 0; i < nWidth2; i++)
 189                         pRowTmp3[i] = pReadAcc->GetColor(pRows[nY + 2], pColm[i]);
 190                 }
 191             }
 192
 193             pWriteAcc.reset();
 194
 195             bRet = true;
 196         }
 197
 198         pReadAcc.reset();
 199
 200         if (bRet)
 201         {
 202             const MapMode aMap(aBitmap.GetPrefMapMode());
 203             const Size aPrefSize(aBitmap.GetPrefSize());
 204
 205             aBitmap = aNewBmp;
 206
 207             aBitmap.SetPrefMapMode(aMap);
 208             aBitmap.SetPrefSize(aPrefSize);
 209         }
 210     }
 211
 212     if (bRet)
 213         return BitmapEx(aBitmap);
 214
 215     return BitmapEx();
 216 }
 217
 218 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */