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QAudioFormat Class Reference
[QtMultimedia module]

The QAudioFormat class stores audio parameter information. More...

Types

Methods

Special Methods


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.


Type Documentation

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

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

Method Documentation

QAudioFormat.__init__ (self)

Construct a new audio format.

Values are initialized as follows:

QAudioFormat.__init__ (self, QAudioFormat other)

Construct a new audio format using other.

Endian QAudioFormat.byteOrder (self)

Returns the current byteOrder value.

See also setByteOrder().

int QAudioFormat.channelCount (self)

Returns the current channel count value.

This function was introduced in Qt 4.7.

See also setChannelCount().

int QAudioFormat.channels (self)

QString QAudioFormat.codec (self)

Returns the current codec value.

See also setCodec() and QAudioDeviceInfo.supportedCodecs().

int QAudioFormat.frequency (self)

bool QAudioFormat.isValid (self)

Returns true if all of the parameters are valid.

int QAudioFormat.sampleRate (self)

Returns the current sample rate in Hertz.

This function was introduced in Qt 4.7.

See also setSampleRate().

int QAudioFormat.sampleSize (self)

Returns the current sample size value.

See also setSampleSize().

SampleType QAudioFormat.sampleType (self)

Returns the current SampleType value.

See also setSampleType().

QAudioFormat.setByteOrder (self, Endian byteOrder)

Sets the byteOrder to byteOrder.

See also byteOrder().

QAudioFormat.setChannelCount (self, int channelCount)

Sets the channel count to channels.

This function was introduced in Qt 4.7.

See also channelCount().

QAudioFormat.setChannels (self, int channels)

QAudioFormat.setCodec (self, QString codec)

Sets the codec to codec.

See also codec() and QAudioDeviceInfo.supportedCodecs().

QAudioFormat.setFrequency (self, int frequency)

QAudioFormat.setSampleRate (self, int sampleRate)

Sets the sample rate to samplerate Hertz.

This function was introduced in Qt 4.7.

See also sampleRate().

QAudioFormat.setSampleSize (self, int sampleSize)

Sets the sample size to the sampleSize specified.

See also sampleSize().

QAudioFormat.setSampleType (self, SampleType sampleType)

Sets the sampleType to sampleType.

See also sampleType().

bool QAudioFormat.__eq__ (self, QAudioFormat other)

bool QAudioFormat.__ne__ (self, QAudioFormat other)


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