1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
/****************************************************************************
**
** Copyright (C) 2014 Digia Plc
** All rights reserved.
** For any questions to Digia, please use contact form at http://qt.digia.com
**
** This file is part of the QtDataVisualization module.
**
** Licensees holding valid Qt Enterprise licenses may use this file in
** accordance with the Qt Enterprise License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.
**
** If you have questions regarding the use of this file, please use
** contact form at http://qt.digia.com
**
****************************************************************************/
#include <qendian.h>
#include <QVector>
#include <QDebug>
#include "utils.h"
#include "wavfile.h"
struct chunk
{
char id[4];
quint32 size;
};
struct RIFFHeader
{
chunk descriptor; // "RIFF"
char type[4]; // "WAVE"
};
struct WAVEHeader
{
chunk descriptor;
quint16 audioFormat;
quint16 numChannels;
quint32 sampleRate;
quint32 byteRate;
quint16 blockAlign;
quint16 bitsPerSample;
};
struct DATAHeader
{
chunk descriptor;
};
struct CombinedHeader
{
RIFFHeader riff;
WAVEHeader wave;
};
WavFile::WavFile(QObject *parent)
: QFile(parent),
m_headerLength(0)
{
}
bool WavFile::open(const QString &fileName)
{
close();
setFileName(fileName);
return QFile::open(QIODevice::ReadOnly) && readHeader();
}
const QAudioFormat &WavFile::fileFormat() const
{
return m_fileFormat;
}
qint64 WavFile::headerLength() const
{
return m_headerLength;
}
bool WavFile::readHeader()
{
seek(0);
CombinedHeader header;
bool result = read(reinterpret_cast<char *>(&header), sizeof(CombinedHeader)) == sizeof(CombinedHeader);
if (result) {
if ((memcmp(&header.riff.descriptor.id, "RIFF", 4) == 0
|| memcmp(&header.riff.descriptor.id, "RIFX", 4) == 0)
&& memcmp(&header.riff.type, "WAVE", 4) == 0
&& memcmp(&header.wave.descriptor.id, "fmt ", 4) == 0
&& (header.wave.audioFormat == 1 || header.wave.audioFormat == 0)) {
// Read off remaining header information
DATAHeader dataHeader;
if (qFromLittleEndian<quint32>(header.wave.descriptor.size) > sizeof(WAVEHeader)) {
// Extended data available
quint16 extraFormatBytes;
if (peek((char*)&extraFormatBytes, sizeof(quint16)) != sizeof(quint16))
return false;
const qint64 throwAwayBytes = sizeof(quint16) + qFromLittleEndian<quint16>(extraFormatBytes);
if (read(throwAwayBytes).size() != throwAwayBytes)
return false;
}
if (read((char*)&dataHeader, sizeof(DATAHeader)) != sizeof(DATAHeader))
return false;
// Establish format
if (memcmp(&header.riff.descriptor.id, "RIFF", 4) == 0)
m_fileFormat.setByteOrder(QAudioFormat::LittleEndian);
else
m_fileFormat.setByteOrder(QAudioFormat::BigEndian);
int bps = qFromLittleEndian<quint16>(header.wave.bitsPerSample);
m_fileFormat.setChannelCount(qFromLittleEndian<quint16>(header.wave.numChannels));
m_fileFormat.setCodec("audio/pcm");
m_fileFormat.setSampleRate(qFromLittleEndian<quint32>(header.wave.sampleRate));
m_fileFormat.setSampleSize(qFromLittleEndian<quint16>(header.wave.bitsPerSample));
m_fileFormat.setSampleType(bps == 8 ? QAudioFormat::UnSignedInt : QAudioFormat::SignedInt);
} else {
result = false;
}
}
m_headerLength = pos();
return result;
}
|
