diff options
Diffstat (limited to 'src/graphics/FilterGetAlpha.cpp')
-rw-r--r-- | src/graphics/FilterGetAlpha.cpp | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/src/graphics/FilterGetAlpha.cpp b/src/graphics/FilterGetAlpha.cpp new file mode 100644 index 0000000..764c47d --- /dev/null +++ b/src/graphics/FilterGetAlpha.cpp @@ -0,0 +1,66 @@ +// +// libavg - Media Playback Engine. +// Copyright (C) 2003-2014 Ulrich von Zadow +// +// This library is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser 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 +// Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License along with this library; if not, write to the Free Software +// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +// +// Current versions can be found at www.libavg.de +// + +#include "FilterGetAlpha.h" +#include "Pixeldefs.h" + +#include "../base/Exception.h" + +#include <iostream> + +namespace avg { + +using namespace std; + +FilterGetAlpha::FilterGetAlpha() + : Filter() +{ +} + +FilterGetAlpha::~FilterGetAlpha() +{ + +} + +BitmapPtr FilterGetAlpha::apply(BitmapPtr pBmpSrc) +{ + PixelFormat pf = pBmpSrc->getPixelFormat(); + AVG_ASSERT(pf == R8G8B8A8 || pf == B8G8R8A8); + BitmapPtr pBmpDest = BitmapPtr(new Bitmap(pBmpSrc->getSize(), I8, + pBmpSrc->getName()+"alpha")); + unsigned char * pSrcLine = pBmpSrc->getPixels(); + unsigned char * pDestLine = pBmpDest->getPixels(); + IntPoint size = pBmpDest->getSize(); + for (int y = 0; y < size.y; ++y) { + unsigned char * pSrcPixel = pSrcLine; + unsigned char * pDstPixel = pDestLine; + for (int x = 0; x < size.x; ++x) { + *pDstPixel = pSrcPixel[ALPHAPOS]; + pSrcPixel += 4; + ++pDstPixel; + } + pSrcLine = pSrcLine + pBmpSrc->getStride(); + pDestLine = pDestLine + pBmpDest->getStride(); + } + return pBmpDest; +} + +} |