Files
libreoffice/vcl/source/bitmap/BitmapScaleConvolution.cxx
Chris Sherlock 88730cdae3 vcl: bmpacc.hxx -> bitmapaccess.hxx
Change-Id: I4bb19d6103c4a6a902d86b62a857e3478493924c
2016-02-06 21:04:09 +11:00

398 lines
12 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include "BitmapScaleConvolution.hxx"
#include "ResampleKernel.hxx"
#include <vcl/bitmapaccess.hxx>
#include <osl/diagnose.h>
#include <algorithm>
#include <memory>
namespace vcl
{
namespace
{
void ImplCalculateContributions(
const long aSourceSize,
const long aDestinationSize,
long& aNumberOfContributions,
double*& pWeights,
long*& pPixels,
long*& pCount,
const Kernel& aKernel)
{
const double fSamplingRadius(aKernel.GetWidth());
const double fScale(aDestinationSize / static_cast< double >(aSourceSize));
const double fScaledRadius((fScale < 1.0) ? fSamplingRadius / fScale : fSamplingRadius);
const double fFilterFactor((fScale < 1.0) ? fScale : 1.0);
aNumberOfContributions = (long(fabs(ceil(fScaledRadius))) * 2) + 1;
const long nAllocSize(aDestinationSize * aNumberOfContributions);
pWeights = new double[nAllocSize];
pPixels = new long[nAllocSize];
pCount = new long[aDestinationSize];
for(long i(0); i < aDestinationSize; i++)
{
const long aIndex(i * aNumberOfContributions);
const double aCenter(i / fScale);
const sal_Int32 aLeft(static_cast< sal_Int32 >(floor(aCenter - fScaledRadius)));
const sal_Int32 aRight(static_cast< sal_Int32 >(ceil(aCenter + fScaledRadius)));
long aCurrentCount(0);
for(sal_Int32 j(aLeft); j <= aRight; j++)
{
const double aWeight(aKernel.Calculate(fFilterFactor * (aCenter - static_cast< double>(j))));
// Reduce calculations with ignoring weights of 0.0
if(fabs(aWeight) < 0.0001)
{
continue;
}
// Handling on edges
const long aPixelIndex(MinMax(j, 0, aSourceSize - 1));
const long nIndex(aIndex + aCurrentCount);
pWeights[nIndex] = aWeight;
pPixels[nIndex] = aPixelIndex;
aCurrentCount++;
}
pCount[i] = aCurrentCount;
}
}
bool ImplScaleConvolutionHor(Bitmap& rSource, Bitmap& rTarget, const double& rScaleX, const Kernel& aKernel)
{
// Do horizontal filtering
OSL_ENSURE(rScaleX > 0.0, "Error in scaling: Mirror given in non-mirror-capable method (!)");
const long nWidth(rSource.GetSizePixel().Width());
const long nNewWidth(FRound(nWidth * rScaleX));
if(nWidth == nNewWidth)
{
return true;
}
BitmapReadAccess* pReadAcc = rSource.AcquireReadAccess();
if(pReadAcc)
{
double* pWeights = nullptr;
long* pPixels = nullptr;
long* pCount = nullptr;
long aNumberOfContributions(0);
const long nHeight(rSource.GetSizePixel().Height());
ImplCalculateContributions(nWidth, nNewWidth, aNumberOfContributions, pWeights, pPixels, pCount, aKernel);
rTarget = Bitmap(Size(nNewWidth, nHeight), 24);
BitmapWriteAccess* pWriteAcc = rTarget.AcquireWriteAccess();
bool bResult(nullptr != pWriteAcc);
if(bResult)
{
for(long y(0); y < nHeight; y++)
{
for(long x(0); x < nNewWidth; x++)
{
const long aBaseIndex(x * aNumberOfContributions);
double aSum(0.0);
double aValueRed(0.0);
double aValueGreen(0.0);
double aValueBlue(0.0);
for(long j(0); j < pCount[x]; j++)
{
const long aIndex(aBaseIndex + j);
const double aWeight(pWeights[aIndex]);
BitmapColor aColor;
aSum += aWeight;
if(pReadAcc->HasPalette())
{
aColor = pReadAcc->GetPaletteColor(pReadAcc->GetPixelIndex(y, pPixels[aIndex]));
}
else
{
aColor = pReadAcc->GetPixel(y, pPixels[aIndex]);
}
aValueRed += aWeight * aColor.GetRed();
aValueGreen += aWeight * aColor.GetGreen();
aValueBlue += aWeight * aColor.GetBlue();
}
const BitmapColor aResultColor(
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueRed / aSum), 0, 255)),
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueGreen / aSum), 0, 255)),
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueBlue / aSum), 0, 255)));
pWriteAcc->SetPixel(y, x, aResultColor);
}
}
Bitmap::ReleaseAccess(pWriteAcc);
}
Bitmap::ReleaseAccess(pReadAcc);
delete[] pWeights;
delete[] pCount;
delete[] pPixels;
if(bResult)
{
return true;
}
}
return false;
}
bool ImplScaleConvolutionVer(Bitmap& rSource, Bitmap& rTarget, const double& rScaleY, const Kernel& aKernel)
{
// Do vertical filtering
OSL_ENSURE(rScaleY > 0.0, "Error in scaling: Mirror given in non-mirror-capable method (!)");
const long nHeight(rSource.GetSizePixel().Height());
const long nNewHeight(FRound(nHeight * rScaleY));
if(nHeight == nNewHeight)
{
return true;
}
BitmapReadAccess* pReadAcc = rSource.AcquireReadAccess();
if(pReadAcc)
{
double* pWeights = nullptr;
long* pPixels = nullptr;
long* pCount = nullptr;
long aNumberOfContributions(0);
const long nWidth(rSource.GetSizePixel().Width());
ImplCalculateContributions(nHeight, nNewHeight, aNumberOfContributions, pWeights, pPixels, pCount, aKernel);
rTarget = Bitmap(Size(nWidth, nNewHeight), 24);
BitmapWriteAccess* pWriteAcc = rTarget.AcquireWriteAccess();
bool bResult(nullptr != pWriteAcc);
if(pWriteAcc)
{
for(long x(0); x < nWidth; x++)
{
for(long y(0); y < nNewHeight; y++)
{
const long aBaseIndex(y * aNumberOfContributions);
double aSum(0.0);
double aValueRed(0.0);
double aValueGreen(0.0);
double aValueBlue(0.0);
for(long j(0); j < pCount[y]; j++)
{
const long aIndex(aBaseIndex + j);
const double aWeight(pWeights[aIndex]);
BitmapColor aColor;
aSum += aWeight;
if(pReadAcc->HasPalette())
{
aColor = pReadAcc->GetPaletteColor(pReadAcc->GetPixelIndex(pPixels[aIndex], x));
}
else
{
aColor = pReadAcc->GetPixel(pPixels[aIndex], x);
}
aValueRed += aWeight * aColor.GetRed();
aValueGreen += aWeight * aColor.GetGreen();
aValueBlue += aWeight * aColor.GetBlue();
}
const BitmapColor aResultColor(
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueRed / aSum), 0, 255)),
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueGreen / aSum), 0, 255)),
static_cast< sal_uInt8 >(MinMax(static_cast< sal_Int32 >(aValueBlue / aSum), 0, 255)));
if(pWriteAcc->HasPalette())
{
pWriteAcc->SetPixelIndex(y, x, static_cast< sal_uInt8 >(pWriteAcc->GetBestPaletteIndex(aResultColor)));
}
else
{
pWriteAcc->SetPixel(y, x, aResultColor);
}
}
}
}
Bitmap::ReleaseAccess(pWriteAcc);
Bitmap::ReleaseAccess(pReadAcc);
delete[] pWeights;
delete[] pCount;
delete[] pPixels;
if(bResult)
{
return true;
}
}
return false;
}
bool ImplScaleConvolution(Bitmap& rBitmap, const double& rScaleX, const double& rScaleY, const Kernel& aKernel)
{
const bool bMirrorHor(rScaleX < 0.0);
const bool bMirrorVer(rScaleY < 0.0);
const double fScaleX(bMirrorHor ? -rScaleX : rScaleX);
const double fScaleY(bMirrorVer ? -rScaleY : rScaleY);
const long nWidth(rBitmap.GetSizePixel().Width());
const long nHeight(rBitmap.GetSizePixel().Height());
const long nNewWidth(FRound(nWidth * fScaleX));
const long nNewHeight(FRound(nHeight * fScaleY));
const bool bScaleHor(nWidth != nNewWidth);
const bool bScaleVer(nHeight != nNewHeight);
const bool bMirror(bMirrorHor || bMirrorVer);
if (!bMirror && !bScaleHor && !bScaleVer)
{
return true;
}
bool bResult(true);
BmpMirrorFlags nMirrorFlags(BmpMirrorFlags::NONE);
bool bMirrorAfter(false);
if (bMirror)
{
if(bMirrorHor)
{
nMirrorFlags |= BmpMirrorFlags::Horizontal;
}
if(bMirrorVer)
{
nMirrorFlags |= BmpMirrorFlags::Vertical;
}
const long nStartSize(nWidth * nHeight);
const long nEndSize(nNewWidth * nNewHeight);
bMirrorAfter = nStartSize > nEndSize;
if(!bMirrorAfter)
{
bResult = rBitmap.Mirror(nMirrorFlags);
}
}
Bitmap aResult;
if (bResult)
{
const long nInBetweenSizeHorFirst(nHeight * nNewWidth);
const long nInBetweenSizeVerFirst(nNewHeight * nWidth);
Bitmap aSource(rBitmap);
if(nInBetweenSizeHorFirst < nInBetweenSizeVerFirst)
{
if(bScaleHor)
{
bResult = ImplScaleConvolutionHor(aSource, aResult, fScaleX, aKernel);
}
if(bResult && bScaleVer)
{
if(bScaleHor)
{
// copy partial result, independent of color depth
aSource = aResult;
}
bResult = ImplScaleConvolutionVer(aSource, aResult, fScaleY, aKernel);
}
}
else
{
if(bScaleVer)
{
bResult = ImplScaleConvolutionVer(aSource, aResult, fScaleY, aKernel);
}
if(bResult && bScaleHor)
{
if(bScaleVer)
{
// copy partial result, independent of color depth
aSource = aResult;
}
bResult = ImplScaleConvolutionHor(aSource, aResult, fScaleX, aKernel);
}
}
}
if(bResult && bMirrorAfter)
{
bResult = aResult.Mirror(nMirrorFlags);
}
if(bResult)
{
rBitmap.ImplAdaptBitCount(aResult);
rBitmap = aResult;
}
return bResult;
}
} // end anonymous namespace
bool BitmapScaleConvolution::filter(Bitmap& rBitmap)
{
switch(meKernelType)
{
case ConvolutionKernelType::Box:
return ImplScaleConvolution(rBitmap, mrScaleX, mrScaleY, BoxKernel());
case ConvolutionKernelType::BiLinear:
return ImplScaleConvolution(rBitmap, mrScaleX, mrScaleY, BilinearKernel());
case ConvolutionKernelType::BiCubic:
return ImplScaleConvolution(rBitmap, mrScaleX, mrScaleY, BicubicKernel());
case ConvolutionKernelType::Lanczos3:
return ImplScaleConvolution(rBitmap, mrScaleX, mrScaleY, Lanczos3Kernel());
default:
break;
}
return false;
}
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */