QAudioFormat Class
The QAudioFormat class stores audio parameter information. More...
| Header: | #include <QAudioFormat> |
| Since: | Qt 4.6 |
Public Types
| enum | Endian { BigEndian, LittleEndian } |
| enum | SampleType { Unknown, SignedInt, UnSignedInt, Float } |
Public Functions
| QAudioFormat() | |
| QAudioFormat(const QAudioFormat & other) | |
| ~QAudioFormat() | |
| QAudioFormat::Endian | byteOrder() const |
| int | channelCount() const |
| QString | codec() const |
| bool | isValid() const |
| int | sampleRate() const |
| int | sampleSize() const |
| QAudioFormat::SampleType | sampleType() const |
| void | setByteOrder(QAudioFormat::Endian byteOrder) |
| void | setChannelCount(int channels) |
| void | setCodec(const QString & codec) |
| void | setSampleRate(int samplerate) |
| void | setSampleSize(int sampleSize) |
| void | setSampleType(QAudioFormat::SampleType sampleType) |
| bool | operator!=(const QAudioFormat & other) const |
| QAudioFormat & | operator=(const QAudioFormat & other) |
| bool | operator==(const QAudioFormat & other) const |
Detailed Description
The QAudioFormat class stores audio parameter information.
An audio format specifies how data in an audio stream is arranged, i.e, how the stream is to be interpreted. The encoding itself is specified by the codec() used for the stream.
In addition to the encoding, QAudioFormat contains other parameters that further specify how the audio data is arranged. These are the frequency, the number of channels, the sample size, the sample type, and the byte order. The following table describes these in more detail.
| Parameter | Description |
|---|---|
| Sample Rate | Samples per second of audio data in Hertz. |
| Number of channels | The number of audio channels (typically one for mono or two for stereo) |
| Sample size | How much data is stored in each sample (typically 8 or 16 bits) |
| Sample type | Numerical representation of sample (typically signed integer, unsigned integer or float) |
| Byte order | Byte ordering of sample (typically little endian, big endian) |
You can obtain audio formats compatible with the audio device used through functions in QAudioDeviceInfo. This class also lets you query available parameter values for a device, so that you can set the parameters yourself. See the QAudioDeviceInfo class description for details. You need to know the format of the audio streams you wish to play. Qt does not set up formats for you.
Member Type Documentation
enum QAudioFormat::Endian
| Constant | Value | Description |
|---|---|---|
QAudioFormat::BigEndian | QSysInfo::BigEndian | samples are big endian byte order |
QAudioFormat::LittleEndian | QSysInfo::LittleEndian | samples are little endian byte order |
enum QAudioFormat::SampleType
| Constant | Value | Description |
|---|---|---|
QAudioFormat::Unknown | 0 | Not Set |
QAudioFormat::SignedInt | 1 | samples are signed integers |
QAudioFormat::UnSignedInt | 2 | samples are unsigned intergers |
QAudioFormat::Float | 3 | samples are floats |
Member Function Documentation
QAudioFormat::QAudioFormat()
Construct a new audio format.
Values are initialized as follows:
- sampleRate() = -1
- channelCount() = -1
- sampleSize() = -1
- byteOrder() = QAudioFormat::Endian(QSysInfo::ByteOrder)
- sampleType() = QAudioFormat::Unknown
codec()= ""
QAudioFormat::QAudioFormat(const QAudioFormat & other)
Construct a new audio format using other.
QAudioFormat::~QAudioFormat()
Destroy this audio format.
QAudioFormat::Endian QAudioFormat::byteOrder() const
Returns the current byteOrder value.
See also setByteOrder().
int QAudioFormat::channelCount() const
Returns the current channel count value.
This function was introduced in Qt 4.7.
See also setChannelCount().
QString QAudioFormat::codec() const
Returns the current codec value.
See also setCodec() and QAudioDeviceInfo::supportedCodecs().
bool QAudioFormat::isValid() const
Returns true if all of the parameters are valid.
int QAudioFormat::sampleRate() const
Returns the current sample rate in Hertz.
This function was introduced in Qt 4.7.
See also setSampleRate().
int QAudioFormat::sampleSize() const
Returns the current sample size value.
See also setSampleSize().
QAudioFormat::SampleType QAudioFormat::sampleType() const
Returns the current SampleType value.
See also setSampleType().
void QAudioFormat::setByteOrder(QAudioFormat::Endian byteOrder)
Sets the byteOrder to byteOrder.
See also byteOrder().
void QAudioFormat::setChannelCount(int channels)
Sets the channel count to channels.
This function was introduced in Qt 4.7.
See also channelCount().
void QAudioFormat::setCodec(const QString & codec)
Sets the codec to codec.
See also codec() and QAudioDeviceInfo::supportedCodecs().
void QAudioFormat::setSampleRate(int samplerate)
Sets the sample rate to samplerate Hertz.
This function was introduced in Qt 4.7.
See also sampleRate().
void QAudioFormat::setSampleSize(int sampleSize)
Sets the sample size to the sampleSize specified.
See also sampleSize().
void QAudioFormat::setSampleType(QAudioFormat::SampleType sampleType)
Sets the sampleType to sampleType.
See also sampleType().
bool QAudioFormat::operator!=(const QAudioFormat & other) const
Returns true if this QAudioFormat is not equal to the other QAudioFormat; otherwise returns false.
All elements of QAudioFormat are used for the comparison.
QAudioFormat & QAudioFormat::operator=(const QAudioFormat & other)
Assigns other to this QAudioFormat implementation.
bool QAudioFormat::operator==(const QAudioFormat & other) const
Returns true if this QAudioFormat is equal to the other QAudioFormat; otherwise returns false.
All elements of QAudioFormat are used for the comparison.
© 2016 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.