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Breadcrumbs go here --> <li><a href="modules.html">Modules</a></li> <li><a href="phonon.html">Phonon</a></li> <li>Effect</li> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#public-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <h1 class="title">Effect Class Reference</h1> <span class="small-subtitle">(Phonon::Effect)<br/></span> <!-- $$$Effect-brief --> <p>The Effect class is used to transform audio streams. <a href="#details">More...</a></p> <!-- @@@Effect --> <pre class="cpp"> <span class="preprocessor">#include <Phonon/Effect></span></pre><p><b>Inherits: </b><a href="qobject.html">QObject</a> and <a href="phonon-medianode.html">MediaNode</a>.</p> <p>This class was introduced in Qt 4.4.</p> <ul> <li><a href="phonon-effect-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2>Public Functions</h2> <table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="phonon-effect.html#Effect">Effect</a></b> ( const EffectDescription & <i>description</i>, QObject * <i>parent</i> = 0 )</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> EffectDescription </td><td class="memItemRight bottomAlign"><b><a href="phonon-effect.html#description">description</a></b> () const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QVariant </td><td class="memItemRight bottomAlign"><b><a href="phonon-effect.html#parameterValue">parameterValue</a></b> ( const EffectParameter & <i>parameter</i> ) const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QList<EffectParameter> </td><td class="memItemRight bottomAlign"><b><a href="phonon-effect.html#parameters">parameters</a></b> () const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="phonon-effect.html#setParameterValue">setParameterValue</a></b> ( const EffectParameter & <i>parameter</i>, const QVariant & <i>value</i> )</td></tr> </table> <ul> <li class="fn">29 public functions inherited from <a href="qobject.html#public-functions">QObject</a></li> <li class="fn">3 public functions inherited from <a href="phonon-medianode.html#public-functions">Phonon::MediaNode</a></li> </ul> <h3>Additional Inherited Members</h3> <ul> <li class="fn">1 property inherited from <a href="qobject.html#properties">QObject</a></li> <li class="fn">1 public slot inherited from <a href="qobject.html#public-slots">QObject</a></li> <li class="fn">1 signal inherited from <a href="qobject.html#signals">QObject</a></li> <li class="fn">7 static public members inherited from <a href="qobject.html#static-public-members">QObject</a></li> <li class="fn">8 protected functions inherited from <a href="qobject.html#protected-functions">QObject</a></li> </ul> <a name="details"></a> <!-- $$$Effect-description --> <div class="descr"> <h2>Detailed Description</h2> <p>The Effect class is used to transform audio streams.</p> <p>An effect is a media node which is inserted into a path between a <a href="phonon-mediaobject.html">MediaObject</a> and an audio output node, for instance, an <a href="phonon-audiooutput.html">AudioOutput</a>. The Effect transforms the media stream on that path.</p> <p>Examples may include simple modifiers, such as fading or pitch shifting, and more complex mathematical transformations. You can query the backend for available effects with <a href="phonon-backendcapabilities.html#availableAudioEffects">BackendCapabilities::availableAudioEffects</a>(). Note that the effects available is dependent on the underlying system (DirectDraw, GStreamer, or QuickTime).</p> <p>In order to use an effect, insert it into the path as follows:</p> <pre class="cpp"> Path path <span class="operator">=</span> Phonon<span class="operator">::</span>createPath(<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>); Effect <span class="operator">*</span>effect <span class="operator">=</span> <span class="keyword">new</span> Effect(<span class="keyword">this</span>); path<span class="operator">.</span>insertEffect(effect);</pre> <p>The effect will immediately begin applying it's transformations on the path. To stop it, remove the Effect from the path.</p> <p>To create an effect, you use the <a href="phonon-objectdescription.html#EffectDescription-typedef">EffectDescription</a> class, which you get from <a href="phonon-backendcapabilities.html#availableAudioEffects">availableAudioEffects()</a>. We give a code example below.</p> <pre class="cpp"> <span class="type"><a href="qlist.html">QList</a></span><span class="operator"><</span>Phonon<span class="operator">::</span>EffectDescription<span class="operator">></span> effectDescriptions <span class="operator">=</span> Phonon<span class="operator">::</span>BackendCapabilities<span class="operator">::</span>availableAudioEffects(); Phonon<span class="operator">::</span>EffectDescription effectDescription <span class="operator">=</span> effectDescriptions<span class="operator">.</span>at(<span class="number">4</span>); Phonon<span class="operator">::</span>Path path <span class="operator">=</span> Phonon<span class="operator">::</span>createPath(mediaObject<span class="operator">,</span> audioOutput); Phonon<span class="operator">::</span>Effect <span class="operator">*</span>effect <span class="operator">=</span> <span class="keyword">new</span> Phonon<span class="operator">::</span>Effect(effectDescription); path<span class="operator">.</span>insertEffect(effect);</pre> <p>An effect can have one or more parameters, which let you alter how the effect works, for instance, by specifying the depth of a reverb effect. See the <a href="phonon-effectparameter.html">EffectParameter</a> class description for details.</p> <p>Phonon also provides <a href="phonon-effectwidget.html">EffectWidget</a>, which lets the user modify the parameters of an effect an the fly; e.g., with combo boxes.</p> </div> <p><b>See also </b><a href="phonon-module.html">Phonon Module</a> and <a href="phonon-effectwidget.html">EffectWidget</a>.</p> <!-- @@@Effect --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$Effect[overload1]$$$EffectconstEffectDescription&QObject* --> <h3 class="fn"><a name="Effect"></a>Effect::<span class="name">Effect</span> ( const <span class="type"><a href="phonon-objectdescription.html#EffectDescription-typedef">EffectDescription</a></span> & <i>description</i>, <span class="type"><a href="qobject.html">QObject</a></span> * <i>parent</i> = 0 )</h3> <p>Constructs a new effect object with the given <i>description</i> and <i>parent</i> object.</p> <p>The <a href="phonon-objectdescription.html#EffectDescription-typedef">EffectDescription</a> object determines the type of the effect.</p> <p><b>See also </b><a href="phonon-backendcapabilities.html#availableAudioEffects">Phonon::BackendCapabilities::availableAudioEffects</a>().</p> <!-- @@@Effect --> <!-- $$$description[overload1]$$$description --> <h3 class="fn"><a name="description"></a><span class="type"><a href="phonon-objectdescription.html#EffectDescription-typedef">EffectDescription</a></span> Effect::<span class="name">description</span> () const</h3> <p>Returns the description of this effect. This is the same description that was passed to the constructor.</p> <!-- @@@description --> <!-- $$$parameterValue[overload1]$$$parameterValueconstEffectParameter& --> <h3 class="fn"><a name="parameterValue"></a><span class="type"><a href="qvariant.html">QVariant</a></span> Effect::<span class="name">parameterValue</span> ( const <span class="type"><a href="phonon-effectparameter.html">EffectParameter</a></span> & <i>parameter</i> ) const</h3> <p>Returns the value of the given effect <i>parameter</i>. You can fetch the available parameters for an effect with <a href="phonon-effect.html#parameters">parameters</a>().</p> <p><b>See also </b><a href="phonon-effect.html#setParameterValue">setParameterValue</a>() and <a href="phonon-effectparameter.html">EffectParameter</a>.</p> <!-- @@@parameterValue --> <!-- $$$parameters[overload1]$$$parameters --> <h3 class="fn"><a name="parameters"></a><span class="type"><a href="qlist.html">QList</a></span><<span class="type"><a href="phonon-effectparameter.html">EffectParameter</a></span>> Effect::<span class="name">parameters</span> () const</h3> <p>Returns a list of parameters that this effect provides to control its behavior.</p> <p><b>See also </b><a href="phonon-effectparameter.html">EffectParameter</a> and <a href="phonon-effectwidget.html">EffectWidget</a>.</p> <!-- @@@parameters --> <!-- $$$setParameterValue[overload1]$$$setParameterValueconstEffectParameter&constQVariant& --> <h3 class="fn"><a name="setParameterValue"></a><span class="type">void</span> Effect::<span class="name">setParameterValue</span> ( const <span class="type"><a href="phonon-effectparameter.html">EffectParameter</a></span> & <i>parameter</i>, const <span class="type"><a href="qvariant.html">QVariant</a></span> & <i>value</i> )</h3> <p>Sets the given effect <i>parameter</i> to the specified <i>value</i>.</p> <p>Parameters for an effect are returned by <a href="phonon-effect.html#parameters">parameters</a>(). You can check which <a href="qvariant.html#Type-enum">QVariant::Type</a> an <a href="phonon-effectparameter.html">EffectParameter</a> takes with the <a href="phonon-effectparameter.html#type">EffectParameter::type</a>() function.</p> <p><b>See also </b><a href="phonon-effect.html#parameterValue">parameterValue</a>() and <a href="phonon-effectparameter.html">EffectParameter</a>.</p> <!-- @@@setParameterValue --> </div> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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