qtmobility/plugins/multimedia/pulseaudio/wavedecoder.cpp
changeset 1 2b40d63a9c3d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/qtmobility/plugins/multimedia/pulseaudio/wavedecoder.cpp	Fri Apr 16 15:51:22 2010 +0300
@@ -0,0 +1,137 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the Qt Mobility Components.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, 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.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "wavedecoder.h"
+
+#include <QtCore/qtimer.h>
+#include <QtCore/qendian.h>
+#include <QDebug>
+
+WaveDecoder::WaveDecoder(QIODevice *s, QObject *parent):
+    QIODevice(parent),
+    haveFormat(false),
+    dataSize(0),
+    remaining(0),
+    source(s)
+{
+    open(QIODevice::ReadOnly | QIODevice::Unbuffered);
+
+    if (source->bytesAvailable() >= sizeof(CombinedHeader))
+        QTimer::singleShot(0, this, SLOT(handleData()));
+    else
+        connect(source, SIGNAL(readyRead()), SLOT(handleData()));
+}
+
+WaveDecoder::~WaveDecoder()
+{
+}
+
+QAudioFormat WaveDecoder::audioFormat() const
+{
+    return format;
+}
+
+int WaveDecoder::duration() const
+{
+    return size() * 1000 / (format.sampleSize() / 8) / format.channels() / format.frequency();
+}
+
+qint64 WaveDecoder::size() const
+{
+    return haveFormat ? dataSize : 0;
+}
+
+bool WaveDecoder::isSequential() const
+{
+    return source->isSequential();
+}
+
+qint64 WaveDecoder::bytesAvailable() const
+{
+    return haveFormat ? source->bytesAvailable() : 0;
+}
+
+qint64 WaveDecoder::readData(char *data, qint64 maxlen)
+{
+    return haveFormat ? source->read(data, maxlen) : 0;
+}
+
+qint64 WaveDecoder::writeData(const char *data, qint64 len)
+{
+    Q_UNUSED(data);
+    Q_UNUSED(len);
+
+    return -1;
+}
+
+void WaveDecoder::handleData()
+{
+    if (source->bytesAvailable() < sizeof(CombinedHeader))
+        return;
+
+    source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
+    source->read((char*)&header, sizeof(CombinedHeader));
+
+    if (qstrncmp(header.riff.descriptor.id, "RIFF", 4) != 0 ||
+        qstrncmp(header.riff.type, "WAVE", 4) != 0 ||
+        qstrncmp(header.wave.descriptor.id, "fmt ", 4) != 0 ||
+        (header.wave.audioFormat != 0 && header.wave.audioFormat != 1) ||
+        qstrncmp(header.data.descriptor.id, "data", 4) != 0) {
+
+        emit invalidFormat();
+    }
+    else {
+        int bps = qFromLittleEndian<quint16>(header.wave.bitsPerSample);
+
+        format.setCodec("audio/pcm");
+        format.setSampleType(bps == 8 ? QAudioFormat::UnSignedInt : QAudioFormat::SignedInt);
+        format.setByteOrder(QAudioFormat::LittleEndian);
+        format.setFrequency(qFromLittleEndian<quint32>(header.wave.sampleRate));
+        format.setSampleSize(bps);
+        format.setChannels(qFromLittleEndian<quint16>(header.wave.numChannels));
+
+        dataSize = qFromLittleEndian<quint32>(header.data.descriptor.size);
+
+        haveFormat = true;
+        connect(source, SIGNAL(readyRead()), SIGNAL(readyRead()));
+        emit formatKnown();
+    }
+}