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Audio effect to gradually fade the audio volume. Author: Matthias Kretz <kretz@kde.org> More...
#include <Phonon>
Audio effect to gradually fade the audio volume. Author: Matthias Kretz <kretz@kde.org>
This effect differs from gradually changing the output volume in that a dedicated effect can change the volume in the smallest possible steps while every other volume control will make more or less noticeable steps.
See also AudioOutput::volume.
Determines the curve of the volume change.
Constant | Value | Description |
---|---|---|
Phonon::VolumeFaderEffect::Fade3Decibel | 0 | Crossfade curve/fast fade out. This is the default fade curve. |
Phonon::VolumeFaderEffect::Fade6Decibel | 1 | Linear fade out. |
Phonon::VolumeFaderEffect::Fade9Decibel | 2 | Slow fade out. |
Phonon::VolumeFaderEffect::Fade12Decibel | 3 | A more extreme version of the -9dB fade. |
Notes:
Fade3Decibel is often the best fade for a crossfade, as after half of the time the volume reached -3dB. This means that half the possible power (which is proportional to the square of the voltage) is reached. Summed, the maximum power of two audio signals fading with a -3dB curve will always be equal.
For fading in or out the -3dB curve is too abrupt in the end.
With a -6dB fade curve, a volume of -6dB is reached after half of the fading time. -6dB is equal to half of the voltage meaning that the voltage multiplier changes linearly from the start of the fade to the end.
With the Fade9Decibel fade, a volume of -9dB is reached after half of the fade time, so the fade is fast in the beginning and slow at the end. This is a good fade for ending music.
This property holds the fade curve to be used for the fadeIn(), fadeOut() and fadeTo() slots.
Defaults to Fade3Decibel.
Access functions:
See also FadeCurve.
This is the current volume of the output as voltage factor. Setting this property changes the volume immediately.
1.0 means 100%, 0.5 means 50% voltage/25% power, 0.0 means 0%
Access functions:
See also volumeDecibel.
This is the current volume of the output in decibel. Setting this property changes the volume immediately.
0 dB means no change in volume, -6dB means an attenuation of the voltage to 50% and an attenuation of the power to 25%, -inf dB means silence.
Access functions:
See also volume.
Tells the Fader to change the volume from the current volume to 100% in fadeTime milliseconds.
Short for fadeTo(1.0, fadeTime).
fadeTime the fade duration in milliseconds
Tells the Fader to change the volume from the current volume to 0% in fadeTime milliseconds. Short for fadeTo(0.0, fadeTime).
fadeTime the fade duration in milliseconds
See also fadeTo.
Tells the Fader to change the volume from the current value to volume in fadeTime milliseconds.
See also fadeIn() and fadeOut().
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