| /* |
| Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org> |
| 2004, 2005 Rob Buis <buis@kde.org> |
| 2005 Eric Seidel <eric@webkit.org> |
| 2009 Dirk Schulze <krit@webkit.org> |
| |
| This library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public |
| License as published by the Free Software Foundation; either |
| version 2 of the License, or (at your option) any later version. |
| |
| This library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public License |
| aint with this library; see the file COPYING.LIB. If not, write to |
| the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| Boston, MA 02110-1301, USA. |
| */ |
| |
| #include "config.h" |
| |
| #if ENABLE(FILTERS) |
| #include "FEGaussianBlur.h" |
| |
| #include "CanvasPixelArray.h" |
| #include "Filter.h" |
| #include "GraphicsContext.h" |
| #include "ImageData.h" |
| #include <math.h> |
| #include <wtf/MathExtras.h> |
| |
| namespace WebCore { |
| |
| FEGaussianBlur::FEGaussianBlur(FilterEffect* in, const float& x, const float& y) |
| : FilterEffect() |
| , m_in(in) |
| , m_x(x) |
| , m_y(y) |
| { |
| } |
| |
| PassRefPtr<FEGaussianBlur> FEGaussianBlur::create(FilterEffect* in, const float& x, const float& y) |
| { |
| return adoptRef(new FEGaussianBlur(in, x, y)); |
| } |
| |
| float FEGaussianBlur::stdDeviationX() const |
| { |
| return m_x; |
| } |
| |
| void FEGaussianBlur::setStdDeviationX(float x) |
| { |
| m_x = x; |
| } |
| |
| float FEGaussianBlur::stdDeviationY() const |
| { |
| return m_y; |
| } |
| |
| void FEGaussianBlur::setStdDeviationY(float y) |
| { |
| m_y = y; |
| } |
| |
| static void boxBlur(CanvasPixelArray*& srcPixelArray, CanvasPixelArray*& dstPixelArray, |
| unsigned dx, int stride, int strideLine, int effectWidth, int effectHeight, bool alphaImage) |
| { |
| int dxLeft = dx / 2; |
| int dxRight = dx - dxLeft; |
| |
| for (int y = 0; y < effectHeight; ++y) { |
| int line = y * strideLine; |
| for (int channel = 3; channel >= 0; --channel) { |
| int sum = 0; |
| // Fill the kernel |
| int maxKernelSize = std::min(dxRight, effectWidth); |
| for (int i = 0; i < maxKernelSize; ++i) |
| sum += srcPixelArray->get(line + i * stride + channel); |
| |
| // Blurring |
| for (int x = 0; x < effectWidth; ++x) { |
| int pixelByteOffset = line + x * stride + channel; |
| dstPixelArray->set(pixelByteOffset, static_cast<unsigned char>(sum / dx)); |
| if (x >= dxLeft) |
| sum -= srcPixelArray->get(pixelByteOffset - dxLeft * stride); |
| if (x + dxRight < effectWidth) |
| sum += srcPixelArray->get(pixelByteOffset + dxRight * stride); |
| } |
| if (alphaImage) // Source image is black, it just has different alpha values |
| break; |
| } |
| } |
| } |
| |
| void FEGaussianBlur::apply(Filter* filter) |
| { |
| m_in->apply(filter); |
| if (!m_in->resultImage()) |
| return; |
| |
| if (!getEffectContext()) |
| return; |
| |
| setIsAlphaImage(m_in->isAlphaImage()); |
| |
| if (m_x == 0 || m_y == 0) |
| return; |
| |
| unsigned sdx = static_cast<unsigned>(floor(m_x * 3 * sqrt(2 * piDouble) / 4.f + 0.5f)); |
| unsigned sdy = static_cast<unsigned>(floor(m_y * 3 * sqrt(2 * piDouble) / 4.f + 0.5f)); |
| |
| IntRect effectDrawingRect = calculateDrawingIntRect(m_in->subRegion()); |
| RefPtr<ImageData> srcImageData(m_in->resultImage()->getPremultipliedImageData(effectDrawingRect)); |
| CanvasPixelArray* srcPixelArray(srcImageData->data()); |
| |
| IntRect imageRect(IntPoint(), resultImage()->size()); |
| RefPtr<ImageData> tmpImageData = ImageData::create(imageRect.width(), imageRect.height()); |
| CanvasPixelArray* tmpPixelArray(tmpImageData->data()); |
| |
| int stride = 4 * imageRect.width(); |
| for (int i = 0; i < 3; ++i) { |
| boxBlur(srcPixelArray, tmpPixelArray, sdx, 4, stride, imageRect.width(), imageRect.height(), isAlphaImage()); |
| boxBlur(tmpPixelArray, srcPixelArray, sdy, stride, 4, imageRect.height(), imageRect.width(), isAlphaImage()); |
| } |
| |
| resultImage()->putPremultipliedImageData(srcImageData.get(), imageRect, IntPoint()); |
| } |
| |
| void FEGaussianBlur::dump() |
| { |
| } |
| |
| } // namespace WebCore |
| |
| #endif // ENABLE(FILTERS) |