QSoundEffect

The QSoundEffect class provides a way to play low latency sound effects. More

Inheritance diagram of PySide2.QtMultimedia.QSoundEffect

Synopsis

Functions

Slots

Static functions

Detailed Description

This class allows you to play uncompressed audio files (typically WAV files) in a generally lower latency way, and is suitable for “feedback” type sounds in response to user actions (e.g. virtual keyboard sounds, positive or negative feedback for popup dialogs, or game sounds). If low latency is not important, consider using the QMediaPlayer class instead, since it supports a wider variety of media formats and is less resource intensive.

This example shows how a looping, somewhat quiet sound effect can be played:

QSoundEffect effect;
effect.setSource(QUrl::fromLocalFile("engine.wav"));
effect.setLoopCount(QSoundEffect::Infinite);
effect.setVolume(0.25f);
effect.play();

Typically the sound effect should be reused, which allows all the parsing and preparation to be done ahead of time, and only triggered when necessary. This assists with lower latency audio playback.

    MyGame()
        : m_explosion(this)
    {
        m_explosion.setSource(QUrl::fromLocalFile("explosion.wav"));
        m_explosion.setVolume(0.25f);

        // Set up click handling etc.
        connect(clickSource, &QPushButton::clicked, &m_explosion, &QSoundEffect::play);
    }
private:
    QSoundEffect m_explosion;

Since QSoundEffect requires slightly more resources to achieve lower latency playback, the platform may limit the number of simultaneously playing sound effects.

class QSoundEffect([parent=None])

QSoundEffect(audioDevice[, parent=None])

param parent

QObject

param audioDevice

QAudioDeviceInfo

Creates a QSoundEffect with the given parent .

Creates a QSoundEffect with the given audioDevice and parent .

PySide2.QtMultimedia.QSoundEffect.Loop

Constant

Description

QSoundEffect.Infinite

Used as a parameter to setLoopCount() for infinite looping

PySide2.QtMultimedia.QSoundEffect.Status

Constant

Description

QSoundEffect.Null

No source has been set or the source is null.

QSoundEffect.Loading

The SoundEffect is trying to load the source.

QSoundEffect.Ready

The source is loaded and ready for play.

QSoundEffect.Error

An error occurred during operation, such as failure of loading the source.

PySide2.QtMultimedia.QSoundEffect.category()
Return type

unicode

Returns the current category for this sound effect.

Some platforms can perform different audio routing for different categories, or may allow the user to set different volume levels for different categories.

This setting will be ignored on platforms that do not support audio categories.

See also

setCategory()

PySide2.QtMultimedia.QSoundEffect.categoryChanged()
PySide2.QtMultimedia.QSoundEffect.isLoaded()
Return type

bool

Returns whether the sound effect has finished loading the source() .

PySide2.QtMultimedia.QSoundEffect.isMuted()
Return type

bool

Returns whether this sound effect is muted

PySide2.QtMultimedia.QSoundEffect.isPlaying()
Return type

bool

Returns true if the sound effect is currently playing, or false otherwise

PySide2.QtMultimedia.QSoundEffect.loadedChanged()
PySide2.QtMultimedia.QSoundEffect.loopCount()
Return type

int

Returns the total number of times that this sound effect will be played before stopping.

See the loopsRemaining() method for the number of loops currently remaining.

See also

setLoopCount()

PySide2.QtMultimedia.QSoundEffect.loopCountChanged()
PySide2.QtMultimedia.QSoundEffect.loopsRemaining()
Return type

int

PySide2.QtMultimedia.QSoundEffect.loopsRemainingChanged()
PySide2.QtMultimedia.QSoundEffect.mutedChanged()
PySide2.QtMultimedia.QSoundEffect.play()

Start playback of the sound effect, looping the effect for the number of times as specified in the loops property.

PySide2.QtMultimedia.QSoundEffect.playingChanged()
PySide2.QtMultimedia.QSoundEffect.setCategory(category)
Parameters

category – unicode

Sets the category of this sound effect to category .

Some platforms can perform different audio routing for different categories, or may allow the user to set different volume levels for different categories.

This setting will be ignored on platforms that do not support audio categories.

If this setting is changed while a sound effect is playing it will only take effect when the sound effect has stopped playing.

See also

category()

PySide2.QtMultimedia.QSoundEffect.setLoopCount(loopCount)
Parameters

loopCountint

Set the total number of times to play this sound effect to loopCount .

Setting the loop count to 0 or 1 means the sound effect will be played only once; pass QSoundEffect::Infinite to repeat indefinitely. The loop count can be changed while the sound effect is playing, in which case it will update the remaining loops to the new loopCount .

PySide2.QtMultimedia.QSoundEffect.setMuted(muted)
Parameters

mutedbool

Sets whether to mute this sound effect’s playback.

If muted is true, playback will be muted (silenced), and otherwise playback will occur with the currently specified volume() .

See also

isMuted()

PySide2.QtMultimedia.QSoundEffect.setSource(url)
Parameters

urlQUrl

Set the current URL to play to url .

See also

source()

PySide2.QtMultimedia.QSoundEffect.setVolume(volume)
Parameters

volumeqreal

Sets the sound effect volume to volume .

The volume is scaled linearly from 0.0 (silence) to 1.0 (full volume). Values outside this range will be clamped.

The default volume is 1.0 .

UI volume controls should usually be scaled nonlinearly. For example, using a logarithmic scale will produce linear changes in perceived loudness, which is what a user would normally expect from a volume control. See convertVolume() for more details.

See also

volume()

PySide2.QtMultimedia.QSoundEffect.source()
Return type

QUrl

Returns the URL of the current source to play

See also

setSource()

PySide2.QtMultimedia.QSoundEffect.sourceChanged()
PySide2.QtMultimedia.QSoundEffect.status()
Return type

Status

Returns the current status of this sound effect.

PySide2.QtMultimedia.QSoundEffect.statusChanged()
PySide2.QtMultimedia.QSoundEffect.stop()

Stop current playback.

static PySide2.QtMultimedia.QSoundEffect.supportedMimeTypes()
Return type

list of strings

Returns a list of the supported mime types for this platform.

PySide2.QtMultimedia.QSoundEffect.volume()
Return type

qreal

Returns the current volume of this sound effect, from 0.0 (silent) to 1.0 (maximum volume).

See also

setVolume()

PySide2.QtMultimedia.QSoundEffect.volumeChanged()