/* This file is part of the KDE project | |
Copyright (C) 2006 Matthias Kretz <kretz@kde.org> | |
This library is free software; you can redistribute it and/or | |
modify it under the terms of the GNU Lesser General Public | |
License as published by the Free Software Foundation; either | |
version 2.1 of the License, or (at your option) version 3, or any | |
later version accepted by the membership of KDE e.V. (or its | |
successor approved by the membership of KDE e.V.), Nokia Corporation | |
(or its successors, if any) and the KDE Free Qt Foundation, which shall | |
act as a proxy defined in Section 6 of version 3 of the license. | |
This library is distributed in the hope that it will be useful, | |
but WITHOUT ANY WARRANTY; without even the implied warranty of | |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
Lesser General Public License for more details. | |
You should have received a copy of the GNU Lesser General Public | |
License along with this library. If not, see <http://www.gnu.org/licenses/>. | |
*/ | |
#ifndef PHONON_VOLUMEFADEREFFECT_H | |
#define PHONON_VOLUMEFADEREFFECT_H | |
#include "phonon_export.h" | |
#include "effect.h" | |
QT_BEGIN_HEADER | |
QT_BEGIN_NAMESPACE | |
#ifndef QT_NO_PHONON_VOLUMEFADEREFFECT | |
namespace Phonon | |
{ | |
class VolumeFaderEffectPrivate; | |
/** \class VolumeFaderEffect volumefadereffect.h Phonon/VolumeFaderEffect | |
* Audio effect to gradually fade the audio volume. | |
* | |
* 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. | |
* | |
* \ingroup PhononEffects | |
* \author Matthias Kretz <kretz@kde.org> | |
* \see AudioOutput::volume | |
*/ | |
class PHONON_EXPORT VolumeFaderEffect : public Effect | |
{ | |
Q_OBJECT | |
K_DECLARE_PRIVATE(VolumeFaderEffect) | |
PHONON_HEIR(VolumeFaderEffect) | |
Q_ENUMS(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% | |
* | |
* \see volumeDecibel | |
*/ | |
Q_PROPERTY(float volume READ volume WRITE setVolume) | |
/** | |
* 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. | |
* | |
* \see volume | |
*/ | |
Q_PROPERTY(double volumeDecibel READ volumeDecibel WRITE setVolumeDecibel) | |
/** | |
* This property holds the fade curve to be used for the fadeIn(), fadeOut() | |
* and fadeTo() slots. | |
* | |
* Defaults to Fade3Decibel. | |
* | |
* \see FadeCurve | |
*/ | |
Q_PROPERTY(FadeCurve fadeCurve READ fadeCurve WRITE setFadeCurve) | |
public: | |
/** | |
* Determines the curve of the volume change. | |
*/ | |
enum FadeCurve { | |
/** | |
* "Crossfade curve" / "fast" fade out | |
* | |
* 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. | |
* | |
* This is the default fade curve. | |
*/ | |
Fade3Decibel, | |
/** | |
* "Linear" fade out | |
* | |
* With a -6dB fade curve after half of the fading time -6dB has | |
* been reached. -6dB is equal to half of the voltage meaning | |
* that the voltage multiplier changes linearly from the start | |
* of the fade to the end. | |
*/ | |
Fade6Decibel, | |
/** | |
* "slow" fade out | |
* | |
* After half of the fade time -9dB are reached. So the fade is | |
* fast in the beginning and slow in the end. This is a good | |
* fade for ending music. | |
*/ | |
Fade9Decibel, | |
/** | |
* more extreme version of the -9dB fade | |
*/ | |
Fade12Decibel | |
}; | |
float volume() const; | |
double volumeDecibel() const; | |
FadeCurve fadeCurve() const; | |
public Q_SLOTS: | |
/** | |
* Tells the Fader to change the volume from the current volume to 100% | |
* in \p fadeTime milliseconds. | |
* Short for \c fadeTo(1.0, fadeTime). | |
* | |
* \param fadeTime the fade duration in milliseconds | |
* | |
* \see fadeTo | |
* \see volume | |
*/ | |
void fadeIn(int fadeTime); | |
/** | |
* Tells the Fader to change the volume from the current volume to 0% | |
* in \p fadeTime milliseconds. | |
* Short for \c fadeTo(0.0, fadeTime). | |
* | |
* \param fadeTime the fade duration in milliseconds | |
* | |
* \see fadeTo | |
*/ | |
void fadeOut(int fadeTime); | |
void setVolume(float volume); | |
void setVolumeDecibel(double volumeDecibel); | |
void setFadeCurve(FadeCurve curve); | |
/** | |
* Tells the Fader to change the volume from the current value to | |
* \p volume in \p fadeTime milliseconds | |
* | |
* \see fadeIn | |
* \see fadeOut | |
*/ | |
void fadeTo(float volume, int fadeTime); | |
}; | |
} //namespace Phonon | |
#endif //QT_NO_PHONON_VOLUMEFADEREFFECT | |
QT_END_NAMESPACE | |
QT_END_HEADER | |
// vim: sw=4 ts=4 tw=80 | |
#endif // PHONON_VOLUMEFADEREFFECT_H |