| 1 | // Copyright (C) 2016 The Qt Company Ltd. |
|---|---|
| 2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
| 3 | |
| 4 | #ifndef WAVEDECODER_H |
| 5 | #define WAVEDECODER_H |
| 6 | |
| 7 | #include <QtCore/qiodevice.h> |
| 8 | #include <QtMultimedia/qaudioformat.h> |
| 9 | |
| 10 | |
| 11 | QT_BEGIN_NAMESPACE |
| 12 | |
| 13 | |
| 14 | |
| 15 | class Q_MULTIMEDIA_EXPORT QWaveDecoder : public QIODevice |
| 16 | { |
| 17 | Q_OBJECT |
| 18 | |
| 19 | public: |
| 20 | explicit QWaveDecoder(QIODevice *device, QObject *parent = nullptr); |
| 21 | explicit QWaveDecoder(QIODevice *device, const QAudioFormat &format, |
| 22 | QObject *parent = nullptr); |
| 23 | ~QWaveDecoder(); |
| 24 | |
| 25 | QAudioFormat audioFormat() const; |
| 26 | QIODevice* getDevice(); |
| 27 | int duration() const; |
| 28 | static qint64 headerLength(); |
| 29 | |
| 30 | bool open(QIODevice::OpenMode mode) override; |
| 31 | void close() override; |
| 32 | bool seek(qint64 pos) override; |
| 33 | qint64 pos() const override; |
| 34 | void setIODevice(QIODevice *device); |
| 35 | qint64 size() const override; |
| 36 | bool isSequential() const override; |
| 37 | qint64 bytesAvailable() const override; |
| 38 | |
| 39 | Q_SIGNALS: |
| 40 | void formatKnown(); |
| 41 | void parsingError(); |
| 42 | |
| 43 | private Q_SLOTS: |
| 44 | void handleData(); |
| 45 | |
| 46 | private: |
| 47 | qint64 readData(char *data, qint64 maxlen) override; |
| 48 | qint64 writeData(const char *data, qint64 len) override; |
| 49 | |
| 50 | bool writeHeader(); |
| 51 | bool writeDataLength(); |
| 52 | bool enoughDataAvailable(); |
| 53 | bool findChunk(const char *chunkId); |
| 54 | void discardBytes(qint64 numBytes); |
| 55 | void parsingFailed(); |
| 56 | |
| 57 | enum State { |
| 58 | InitialState, |
| 59 | WaitingForFormatState, |
| 60 | WaitingForDataState |
| 61 | }; |
| 62 | |
| 63 | struct chunk |
| 64 | { |
| 65 | char id[4]; // A four-character code that identifies the representation of the chunk data |
| 66 | // padded on the right with blank characters (ASCII 32) |
| 67 | quint32 size; // Does not include the size of the id or size fields or the pad byte at the end of payload |
| 68 | }; |
| 69 | |
| 70 | bool peekChunk(chunk* pChunk, bool handleEndianness = true); |
| 71 | |
| 72 | struct RIFFHeader |
| 73 | { |
| 74 | chunk descriptor; |
| 75 | char type[4]; |
| 76 | }; |
| 77 | struct WAVEHeader |
| 78 | { |
| 79 | chunk descriptor; |
| 80 | quint16 audioFormat; |
| 81 | quint16 numChannels; |
| 82 | quint32 sampleRate; |
| 83 | quint32 byteRate; |
| 84 | quint16 blockAlign; |
| 85 | quint16 bitsPerSample; |
| 86 | }; |
| 87 | |
| 88 | struct DATAHeader |
| 89 | { |
| 90 | chunk descriptor; |
| 91 | }; |
| 92 | |
| 93 | struct CombinedHeader |
| 94 | { |
| 95 | RIFFHeader riff; |
| 96 | WAVEHeader wave; |
| 97 | DATAHeader data; |
| 98 | }; |
| 99 | static const int HeaderLength = sizeof(CombinedHeader); |
| 100 | |
| 101 | bool haveFormat = false; |
| 102 | bool haveHeader = false; |
| 103 | qint64 dataSize = 0; |
| 104 | QIODevice *device = nullptr; |
| 105 | QAudioFormat format; |
| 106 | State state = InitialState; |
| 107 | quint32 junkToSkip = 0; |
| 108 | bool bigEndian = false; |
| 109 | bool byteSwap = false; |
| 110 | int bps = 0; |
| 111 | }; |
| 112 | |
| 113 | QT_END_NAMESPACE |
| 114 | |
| 115 | #endif // WAVEDECODER_H |
| 116 |