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Diffstat (limited to 'src/multimedia/audio/qaudiohelpers.cpp')
-rw-r--r-- | src/multimedia/audio/qaudiohelpers.cpp | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/src/multimedia/audio/qaudiohelpers.cpp b/src/multimedia/audio/qaudiohelpers.cpp new file mode 100644 index 000000000..994950701 --- /dev/null +++ b/src/multimedia/audio/qaudiohelpers.cpp @@ -0,0 +1,117 @@ +/**************************************************************************** +** +** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). +** Contact: http://www.qt-project.org/ +** +** This file is part of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this +** file. Please review the following information to ensure the GNU Lesser +** General Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU General +** Public License version 3.0 as published by the Free Software Foundation +** and appearing in the file LICENSE.GPL included in the packaging of this +** file. Please review the following information to ensure the GNU General +** Public License version 3.0 requirements will be met: +** http://www.gnu.org/copyleft/gpl.html. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qaudiohelpers_p.h" + +#include <QDebug> + +QT_BEGIN_NAMESPACE + +namespace QAudioHelperInternal +{ + +template<class T> void adjustSamples(qreal factor, const void *src, void *dst, int samples) +{ + const T *pSrc = (const T *)src; + T *pDst = (T*)dst; + for ( int i = 0; i < samples; i++ ) + pDst[i] = pSrc[i] * factor; +} + +// Unsigned samples are biased around 0x80/0x8000 :/ +// This makes a pure template solution a bit unwieldy but possible +template<class T> struct signedVersion {}; +template<> struct signedVersion<quint8> +{ + typedef qint8 TS; + enum {offset = 0x80}; +}; + +template<> struct signedVersion<quint16> +{ + typedef qint16 TS; + enum {offset = 0x8000}; +}; + +template<> struct signedVersion<quint32> +{ + typedef qint32 TS; + enum {offset = 0x80000000}; +}; + +template<class T> void adjustUnsignedSamples(qreal factor, const void *src, void *dst, int samples) +{ + const T *pSrc = (const T *)src; + T *pDst = (T*)dst; + for ( int i = 0; i < samples; i++ ) { + pDst[i] = signedVersion<T>::offset + ((typename signedVersion<T>::TS)(pSrc[i] - signedVersion<T>::offset) * factor); + } +} + +void qMultiplySamples(qreal factor, const QAudioFormat &format, const void* src, void* dest, int len) +{ + int samplesCount = len / (format.sampleSize()/8); + + switch ( format.sampleSize() ) { + case 8: + if (format.sampleType() == QAudioFormat::SignedInt) + QAudioHelperInternal::adjustSamples<qint8>(factor,src,dest,samplesCount); + else if (format.sampleType() == QAudioFormat::UnSignedInt) + QAudioHelperInternal::adjustUnsignedSamples<quint8>(factor,src,dest,samplesCount); + break; + case 16: + if (format.sampleType() == QAudioFormat::SignedInt) + QAudioHelperInternal::adjustSamples<qint16>(factor,src,dest,samplesCount); + else if (format.sampleType() == QAudioFormat::UnSignedInt) + QAudioHelperInternal::adjustUnsignedSamples<quint16>(factor,src,dest,samplesCount); + break; + default: + if (format.sampleType() == QAudioFormat::SignedInt) + QAudioHelperInternal::adjustSamples<qint32>(factor,src,dest,samplesCount); + else if (format.sampleType() == QAudioFormat::UnSignedInt) + QAudioHelperInternal::adjustUnsignedSamples<quint32>(factor,src,dest,samplesCount); + else if (format.sampleType() == QAudioFormat::Float) + QAudioHelperInternal::adjustSamples<float>(factor,src,dest,samplesCount); + } +} +} + +QT_END_NAMESPACE |