diff options
Diffstat (limited to 'src/multimedia/effects/qwavedecoder_p.cpp')
| -rw-r--r-- | src/multimedia/effects/qwavedecoder_p.cpp | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/src/multimedia/effects/qwavedecoder_p.cpp b/src/multimedia/effects/qwavedecoder_p.cpp new file mode 100644 index 000000000..19b262adc --- /dev/null +++ b/src/multimedia/effects/qwavedecoder_p.cpp @@ -0,0 +1,232 @@ +/**************************************************************************** +** +** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** 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 "qwavedecoder_p.h" + +#include <QtCore/qtimer.h> +#include <QtCore/qendian.h> + +QT_BEGIN_NAMESPACE + +QWaveDecoder::QWaveDecoder(QIODevice *s, QObject *parent): + QIODevice(parent), + haveFormat(false), + dataSize(0), + remaining(0), + source(s), + state(QWaveDecoder::InitialState) +{ + open(QIODevice::ReadOnly | QIODevice::Unbuffered); + + if (enoughDataAvailable()) + QTimer::singleShot(0, this, SLOT(handleData())); + else + connect(source, SIGNAL(readyRead()), SLOT(handleData())); +} + +QWaveDecoder::~QWaveDecoder() +{ +} + +QAudioFormat QWaveDecoder::audioFormat() const +{ + return format; +} + +int QWaveDecoder::duration() const +{ + return size() * 1000 / (format.sampleSize() / 8) / format.channels() / format.frequency(); +} + +qint64 QWaveDecoder::size() const +{ + return haveFormat ? dataSize : 0; +} + +bool QWaveDecoder::isSequential() const +{ + return source->isSequential(); +} + +qint64 QWaveDecoder::bytesAvailable() const +{ + return haveFormat ? source->bytesAvailable() : 0; +} + +qint64 QWaveDecoder::readData(char *data, qint64 maxlen) +{ + return haveFormat ? source->read(data, maxlen) : 0; +} + +qint64 QWaveDecoder::writeData(const char *data, qint64 len) +{ + Q_UNUSED(data); + Q_UNUSED(len); + + return -1; +} + +void QWaveDecoder::handleData() +{ + if (state == QWaveDecoder::InitialState) { + if (source->bytesAvailable() < qint64(sizeof(RIFFHeader))) + return; + + RIFFHeader riff; + source->read(reinterpret_cast<char *>(&riff), sizeof(RIFFHeader)); + + if (qstrncmp(riff.descriptor.id, "RIFF", 4) != 0 || + qstrncmp(riff.type, "WAVE", 4) != 0) { + source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData())); + emit invalidFormat(); + + return; + } else { + state = QWaveDecoder::WaitingForFormatState; + } + } + + if (state == QWaveDecoder::WaitingForFormatState) { + if (findChunk("fmt ")) { + chunk descriptor; + source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk)); + + if (source->bytesAvailable() < qint64(descriptor.size + sizeof(chunk))) + return; + + WAVEHeader wave; + source->read(reinterpret_cast<char *>(&wave), sizeof(WAVEHeader)); + if (descriptor.size > sizeof(WAVEHeader)) + discardBytes(descriptor.size - sizeof(WAVEHeader)); + + if (wave.audioFormat != 0 && wave.audioFormat != 1) { + source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData())); + emit invalidFormat(); + + return; + } else { + int bps = qFromLittleEndian<quint16>(wave.bitsPerSample); + + format.setCodec(QLatin1String("audio/pcm")); + format.setSampleType(bps == 8 ? QAudioFormat::UnSignedInt : QAudioFormat::SignedInt); + format.setByteOrder(QAudioFormat::LittleEndian); + format.setFrequency(qFromLittleEndian<quint32>(wave.sampleRate)); + format.setSampleSize(bps); + format.setChannels(qFromLittleEndian<quint16>(wave.numChannels)); + + state = QWaveDecoder::WaitingForDataState; + } + } + } + + if (state == QWaveDecoder::WaitingForDataState) { + if (findChunk("data")) { + source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData())); + + chunk descriptor; + source->read(reinterpret_cast<char *>(&descriptor), sizeof(chunk)); + dataSize = descriptor.size; + + haveFormat = true; + connect(source, SIGNAL(readyRead()), SIGNAL(readyRead())); + emit formatKnown(); + + return; + } + } + + if (source->atEnd()) { + source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData())); + emit invalidFormat(); + + return; + } + +} + +bool QWaveDecoder::enoughDataAvailable() +{ + if (source->bytesAvailable() < qint64(sizeof(chunk))) + return false; + + chunk descriptor; + source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk)); + + if (source->bytesAvailable() < qint64(sizeof(chunk) + descriptor.size)) + return false; + + return true; +} + +bool QWaveDecoder::findChunk(const char *chunkId) +{ + if (source->bytesAvailable() < qint64(sizeof(chunk))) + return false; + + chunk descriptor; + source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk)); + + if (qstrncmp(descriptor.id, chunkId, 4) == 0) + return true; + + while (source->bytesAvailable() >= qint64(sizeof(chunk) + descriptor.size)) { + discardBytes(sizeof(chunk) + descriptor.size); + + source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk)); + + if (qstrncmp(descriptor.id, chunkId, 4) == 0) + return true; + } + + return false; +} + +void QWaveDecoder::discardBytes(qint64 numBytes) +{ + if (source->isSequential()) + source->read(numBytes); + else + source->seek(source->pos() + numBytes); +} + +QT_END_NAMESPACE + +#include "moc_qwavedecoder_p.cpp" |