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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
** of its contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "wavefilewriter.h"
struct Q_PACKED chunk
{
char id[4];
quint32 size;
};
struct Q_PACKED RIFFHeader
{
chunk descriptor; // "RIFF"
char type[4]; // "WAVE"
};
struct Q_PACKED WAVEHeader
{
chunk descriptor;
quint16 audioFormat;
quint16 numChannels;
quint32 sampleRate;
quint32 byteRate;
quint16 blockAlign;
quint16 bitsPerSample;
};
struct Q_PACKED DATAHeader
{
chunk descriptor;
};
struct Q_PACKED CombinedHeader
{
RIFFHeader riff;
WAVEHeader wave;
DATAHeader data;
};
static const int HeaderLength = sizeof(CombinedHeader);
WaveFileWriter::WaveFileWriter(QObject *parent)
: QObject(parent)
, m_dataLength(0)
{
}
WaveFileWriter::~WaveFileWriter()
{
close();
}
bool WaveFileWriter::open(const QString& fileName, const QAudioFormat& format)
{
if (file.isOpen())
return false; // file already open
if (format.codec() != "audio/pcm" || format.sampleType() != QAudioFormat::SignedInt)
return false; // data format is not supported
file.setFileName(fileName);
if (!file.open(QIODevice::WriteOnly))
return false; // unable to open file for writing
if (!writeHeader(format))
return false;
m_format = format;
return true;
}
bool WaveFileWriter::write(const QAudioBuffer &buffer)
{
if (buffer.format() != m_format)
return false; // buffer format has changed
qint64 written = file.write((const char *)buffer.constData(), buffer.byteCount());
m_dataLength += written;
return written == buffer.byteCount();
}
bool WaveFileWriter::close()
{
bool result = false;
if (file.isOpen()) {
Q_ASSERT(m_dataLength < INT_MAX);
result = writeDataLength();
m_dataLength = 0;
file.close();
}
return result;
}
bool WaveFileWriter::writeHeader(const QAudioFormat &format)
{
// check if format is supported
if (format.byteOrder() == QAudioFormat::BigEndian || format.sampleType() != QAudioFormat::SignedInt)
return false;
CombinedHeader header;
memset(&header, 0, HeaderLength);
#ifndef Q_LITTLE_ENDIAN
// only implemented for LITTLE ENDIAN
return false;
#else
// RIFF header
memcpy(header.riff.descriptor.id, "RIFF", 4);
header.riff.descriptor.size = 0; // this will be updated with correct duration:
// m_dataLength + HeaderLength - 8
// WAVE header
memcpy(header.riff.type, "WAVE", 4);
memcpy(header.wave.descriptor.id, "fmt ", 4);
header.wave.descriptor.size = quint32(16);
header.wave.audioFormat = quint16(1);
header.wave.numChannels = quint16(format.channelCount());
header.wave.sampleRate = quint32(format.sampleRate());
header.wave.byteRate = quint32(format.sampleRate() * format.channelCount() * format.sampleSize() / 8);
header.wave.blockAlign = quint16(format.channelCount() * format.sampleSize() / 8);
header.wave.bitsPerSample = quint16(format.sampleSize());
// DATA header
memcpy(header.data.descriptor.id,"data", 4);
header.data.descriptor.size = 0; // this will be updated with correct data length: m_dataLength
return (file.write(reinterpret_cast<const char *>(&header), HeaderLength) == HeaderLength);
#endif
}
bool WaveFileWriter::writeDataLength()
{
#ifndef Q_LITTLE_ENDIAN
// only implemented for LITTLE ENDIAN
return false;
#endif
if (file.isSequential())
return false;
// seek to RIFF header size, see header.riff.descriptor.size above
if (!file.seek(4))
return false;
quint32 length = m_dataLength + HeaderLength - 8;
if (file.write(reinterpret_cast<const char *>(&length), 4) != 4)
return false;
// seek to DATA header size, see header.data.descriptor.size above
if (!file.seek(40))
return false;
return file.write(reinterpret_cast<const char *>(&m_dataLength), 4) == 4;
}
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