vcl/source/bitmap/BitmapInterpolateScaleFilter.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  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <tools/helpers.hxx>
  21 #include <osl/diagnose.h>
  22
  23 #include <vcl/bitmapex.hxx>
  24
  25 #include <bitmap/BitmapWriteAccess.hxx>
  26 #include <bitmap/BitmapFastScaleFilter.hxx>
  27 #include <bitmap/BitmapInterpolateScaleFilter.hxx>
  28
  29 BitmapEx BitmapInterpolateScaleFilter::execute(BitmapEx const& rBitmapEx) const
  30 {
  31     Bitmap aBitmap(rBitmapEx.GetBitmap());
  32
  33     const Size aSizePix(aBitmap.GetSizePixel());
  34     const tools::Long nNewWidth = FRound(aSizePix.Width() * mfScaleX);
  35     const tools::Long nNewHeight = FRound(aSizePix.Height() * mfScaleY);
  36     bool bRet = false;
  37
  38     if ((nNewWidth > 1) && (nNewHeight > 1))
  39     {
  40         Bitmap::ScopedReadAccess pReadAcc(aBitmap);
  41         if (pReadAcc)
  42         {
  43             tools::Long nWidth = pReadAcc->Width();
  44             tools::Long nHeight = pReadAcc->Height();
  45             Bitmap aNewBmp(Size(nNewWidth, nHeight), vcl::PixelFormat::N24_BPP);
  46             BitmapScopedWriteAccess pWriteAcc(aNewBmp);
  47
  48             if (pWriteAcc)
  49             {
  50                 const tools::Long nNewWidth1 = nNewWidth - 1;
  51                 const tools::Long nWidth1 = pReadAcc->Width() - 1;
  52                 const double fRevScaleX = static_cast<double>(nWidth1) / nNewWidth1;
  53
  54                 std::unique_ptr<tools::Long[]> pLutInt(new tools::Long[nNewWidth]);
  55                 std::unique_ptr<tools::Long[]> pLutFrac(new tools::Long[nNewWidth]);
  56
  57                 for (tools::Long nX = 0, nTemp = nWidth - 2; nX < nNewWidth; nX++)
  58                 {
  59                     double fTemp = nX * fRevScaleX;
  60                     pLutInt[nX] = MinMax(static_cast<tools::Long>(fTemp), 0, nTemp);
  61                     fTemp -= pLutInt[nX];
  62                     pLutFrac[nX] = static_cast<tools::Long>(fTemp * 1024.);
  63                 }
  64
  65                 for (tools::Long nY = 0; nY < nHeight; nY++)
  66                 {
  67                     Scanline pScanlineRead = pReadAcc->GetScanline(nY);
  68                     if (1 == nWidth)
  69                     {
  70                         BitmapColor aCol0;
  71                         if (pReadAcc->HasPalette())
  72                         {
  73                             aCol0 = pReadAcc->GetPaletteColor(
  74                                 pReadAcc->GetIndexFromData(pScanlineRead, 0));
  75                         }
  76                         else
  77                         {
  78                             aCol0 = pReadAcc->GetPixelFromData(pScanlineRead, 0);
  79                         }
  80
  81                         Scanline pScanline = pWriteAcc->GetScanline(nY);
  82                         for (tools::Long nX = 0; nX < nNewWidth; nX++)
  83                         {
  84                             pWriteAcc->SetPixelOnData(pScanline, nX, aCol0);
  85                         }
  86                     }
  87                     else
  88                     {
  89                         Scanline pScanline = pWriteAcc->GetScanline(nY);
  90                         for (tools::Long nX = 0; nX < nNewWidth; nX++)
  91                         {
  92                             tools::Long nTemp = pLutInt[nX];
  93
  94                             BitmapColor aCol0, aCol1;
  95                             if (pReadAcc->HasPalette())
  96                             {
  97                                 aCol0 = pReadAcc->GetPaletteColor(
  98                                     pReadAcc->GetIndexFromData(pScanlineRead, nTemp++));
  99                                 aCol1 = pReadAcc->GetPaletteColor(
 100                                     pReadAcc->GetIndexFromData(pScanlineRead, nTemp));
 101                             }
 102                             else
 103                             {
 104                                 aCol0 = pReadAcc->GetPixelFromData(pScanlineRead, nTemp++);
 105                                 aCol1 = pReadAcc->GetPixelFromData(pScanlineRead, nTemp);
 106                             }
 107
 108                             nTemp = pLutFrac[nX];
 109
 110                             tools::Long lXR0 = aCol0.GetRed();
 111                             tools::Long lXG0 = aCol0.GetGreen();
 112                             tools::Long lXB0 = aCol0.GetBlue();
 113                             tools::Long lXR1 = aCol1.GetRed() - lXR0;
 114                             tools::Long lXG1 = aCol1.GetGreen() - lXG0;
 115                             tools::Long lXB1 = aCol1.GetBlue() - lXB0;
 116
 117                             aCol0.SetRed(
 118                                 static_cast<sal_uInt8>((lXR1 * nTemp + (lXR0 << 10)) >> 10));
 119                             aCol0.SetGreen(
 120                                 static_cast<sal_uInt8>((lXG1 * nTemp + (lXG0 << 10)) >> 10));
 121                             aCol0.SetBlue(
 122                                 static_cast<sal_uInt8>((lXB1 * nTemp + (lXB0 << 10)) >> 10));
 123
 124                             pWriteAcc->SetPixelOnData(pScanline, nX, aCol0);
 125                         }
 126                     }
 127                 }
 128
 129                 bRet = true;
 130             }
 131
 132             pReadAcc.reset();
 133             pWriteAcc.reset();
 134
 135             if (bRet)
 136             {
 137                 bRet = false;
 138                 const Bitmap aOriginal(aBitmap);
 139                 aBitmap = aNewBmp;
 140                 aNewBmp = Bitmap(Size(nNewWidth, nNewHeight), vcl::PixelFormat::N24_BPP);
 141                 pReadAcc = Bitmap::ScopedReadAccess(aBitmap);
 142                 pWriteAcc = BitmapScopedWriteAccess(aNewBmp);
 143
 144                 if (pReadAcc && pWriteAcc)
 145                 {
 146                     const tools::Long nNewHeight1 = nNewHeight - 1;
 147                     const tools::Long nHeight1 = pReadAcc->Height() - 1;
 148                     const double fRevScaleY = static_cast<double>(nHeight1) / nNewHeight1;
 149
 150                     std::unique_ptr<tools::Long[]> pLutInt(new tools::Long[nNewHeight]);
 151                     std::unique_ptr<tools::Long[]> pLutFrac(new tools::Long[nNewHeight]);
 152
 153                     for (tools::Long nY = 0, nTemp = nHeight - 2; nY < nNewHeight; nY++)
 154                     {
 155                         double fTemp = nY * fRevScaleY;
 156                         pLutInt[nY] = MinMax(static_cast<tools::Long>(fTemp), 0, nTemp);
 157                         fTemp -= pLutInt[nY];
 158                         pLutFrac[nY] = static_cast<tools::Long>(fTemp * 1024.);
 159                     }
 160
 161                     // after 1st step, bitmap *is* 24bit format (see above)
 162                     OSL_ENSURE(!pReadAcc->HasPalette(), "OOps, somehow ImplScaleInterpolate "
 163                                                         "in-between format has palette, should not "
 164                                                         "happen (!)");
 165
 166                     for (tools::Long nX = 0; nX < nNewWidth; nX++)
 167                     {
 168                         if (1 == nHeight)
 169                         {
 170                             BitmapColor aCol0 = pReadAcc->GetPixel(0, nX);
 171
 172                             for (tools::Long nY = 0; nY < nNewHeight; nY++)
 173                             {
 174                                 pWriteAcc->SetPixel(nY, nX, aCol0);
 175                             }
 176                         }
 177                         else
 178                         {
 179                             for (tools::Long nY = 0; nY < nNewHeight; nY++)
 180                             {
 181                                 tools::Long nTemp = pLutInt[nY];
 182
 183                                 BitmapColor aCol0 = pReadAcc->GetPixel(nTemp++, nX);
 184                                 BitmapColor aCol1 = pReadAcc->GetPixel(nTemp, nX);
 185
 186                                 nTemp = pLutFrac[nY];
 187
 188                                 tools::Long lXR0 = aCol0.GetRed();
 189                                 tools::Long lXG0 = aCol0.GetGreen();
 190                                 tools::Long lXB0 = aCol0.GetBlue();
 191                                 tools::Long lXR1 = aCol1.GetRed() - lXR0;
 192                                 tools::Long lXG1 = aCol1.GetGreen() - lXG0;
 193                                 tools::Long lXB1 = aCol1.GetBlue() - lXB0;
 194
 195                                 aCol0.SetRed(
 196                                     static_cast<sal_uInt8>((lXR1 * nTemp + (lXR0 << 10)) >> 10));
 197                                 aCol0.SetGreen(
 198                                     static_cast<sal_uInt8>((lXG1 * nTemp + (lXG0 << 10)) >> 10));
 199                                 aCol0.SetBlue(
 200                                     static_cast<sal_uInt8>((lXB1 * nTemp + (lXB0 << 10)) >> 10));
 201
 202                                 pWriteAcc->SetPixel(nY, nX, aCol0);
 203                             }
 204                         }
 205                     }
 206
 207                     bRet = true;
 208                 }
 209
 210                 pReadAcc.reset();
 211                 pWriteAcc.reset();
 212
 213                 if (bRet)
 214                 {
 215                     aOriginal.AdaptBitCount(aNewBmp);
 216                     aBitmap = aNewBmp;
 217                 }
 218             }
 219         }
 220     }
 221
 222     if (!bRet)
 223     {
 224         // fallback to fast scale filter
 225         BitmapEx aBmpEx(aBitmap);
 226         bRet = BitmapFilter::Filter(aBmpEx, BitmapFastScaleFilter(mfScaleX, mfScaleY));
 227         aBitmap = aBmpEx.GetBitmap();
 228     }
 229
 230     if (bRet)
 231         return BitmapEx(aBitmap);
 232
 233     return BitmapEx();
 234 }
 235
 236 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */