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<td >Qt 5.12</td><td ><a href="qtmultimedia-index.html">Qt Multimedia</a></td><td ><a href="qtmultimedia-modules.html">C++ Classes</a></td><td >QCameraExposureControl</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtmultimedia-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-types">Public Types</a></li>
<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#signals">Signals</a></li>
<li class="level1"><a href="#static-public-members">Static Public Members</a></li>
<li class="level1"><a href="#protected-functions">Protected Functions</a></li>
<li class="level1"><a href="#macros">Macros</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QCameraExposureControl Class</h1>
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<p>The <a href="qcameraexposurecontrol.html">QCameraExposureControl</a> class allows controlling camera exposure parameters. <a href="#details">More...</a></p>
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<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QCameraExposureControl></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += multimedia</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qmediacontrol.html">QMediaControl</a></td></tr></table></div><ul>
<li><a href="qcameraexposurecontrol-members.html">List of all members, including inherited members</a></li>
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<h2 id="public-types">Public Types</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#ExposureParameter-enum">ExposureParameter</a></b> { ISO, Aperture, ShutterSpeed, ExposureCompensation, ..., ExtendedExposureParameter }</td></tr>
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<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#dtor.QCameraExposureControl">~QCameraExposureControl</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QVariant </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#actualValue">actualValue</a></b>(QCameraExposureControl::ExposureParameter <i>parameter</i>) const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#isParameterSupported">isParameterSupported</a></b>(QCameraExposureControl::ExposureParameter <i>parameter</i>) const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QVariant </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#requestedValue">requestedValue</a></b>(QCameraExposureControl::ExposureParameter <i>parameter</i>) const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#setValue">setValue</a></b>(QCameraExposureControl::ExposureParameter <i>parameter</i>, const QVariant &<i>value</i>) = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QVariantList </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#supportedParameterRange">supportedParameterRange</a></b>(QCameraExposureControl::ExposureParameter <i>parameter</i>, bool *<i>continuous</i>) const = 0</td></tr>
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<h2 id="signals">Signals</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#actualValueChanged">actualValueChanged</a></b>(int <i>parameter</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#parameterRangeChanged">parameterRangeChanged</a></b>(int <i>parameter</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#requestedValueChanged">requestedValueChanged</a></b>(int <i>parameter</i>)</td></tr>
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<h2 id="static-public-members">Static Public Members</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> const QMetaObject </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#staticMetaObject-var">staticMetaObject</a></b></td></tr>
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<h2 id="protected-functions">Protected Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#QCameraExposureControl">QCameraExposureControl</a></b>(QObject *<i>parent</i> = nullptr)</td></tr>
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<h2 id="macros">Macros</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qcameraexposurecontrol.html#QCameraExposureControl_iid">QCameraExposureControl_iid</a></b></td></tr>
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<a name="details"></a>
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<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qcameraexposurecontrol.html">QCameraExposureControl</a> class allows controlling camera exposure parameters.</p>
<p>The <a href="qcameraexposure.html">QCameraExposure</a> class is the usual method of adjusting exposure related parameters when using camera functionality. This class provides a more complete but less easy to use interface, and also forms the interface to implement when writing a new implementation of <a href="qcamera.html">QCamera</a> functionality.</p>
<p>You can adjust a number of parameters that will affect images and video taken with the corresponding <a href="qcamera.html">QCamera</a> object - see the <a href="qcameraexposurecontrol.html#ExposureParameter-enum">ExposureParameter</a> enumeration.</p>
<p>The interface name of <a href="qcameraexposurecontrol.html">QCameraExposureControl</a> is <code>org.qt-project.qt.cameraexposurecontrol/5.0</code> as defined in <a href="qcameraexposurecontrol.html#QCameraExposureControl_iid">QCameraExposureControl_iid</a>.</p>
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<p><b>See also </b><a href="qcameraexposure.html">QCameraExposure</a> and <a href="qcamera.html">QCamera</a>.</p>
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<div class="types">
<h2>Member Type Documentation</h2>
<!-- $$$ExposureParameter$$$ISO$$$Aperture$$$ShutterSpeed$$$ExposureCompensation$$$FlashPower$$$FlashCompensation$$$TorchPower$$$SpotMeteringPoint$$$ExposureMode$$$MeteringMode$$$ExtendedExposureParameter -->
<h3 class="fn" id="ExposureParameter-enum"><a name="ExposureParameter-enum"></a>enum QCameraExposureControl::<span class="name">ExposureParameter</span></h3>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::ISO</code></td><td class="topAlign tblval"><code>0</code></td><td class="topAlign">Camera ISO sensitivity, specified as integer value.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::Aperture</code></td><td class="topAlign tblval"><code>1</code></td><td class="topAlign">Lens aperture is specified as an qreal F number. The supported apertures list can change depending on the focal length, in such a case the exposureParameterRangeChanged() signal is emitted.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::ShutterSpeed</code></td><td class="topAlign tblval"><code>2</code></td><td class="topAlign">Shutter speed in seconds, specified as qreal.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::ExposureCompensation</code></td><td class="topAlign tblval"><code>3</code></td><td class="topAlign">Exposure compensation, specified as qreal EV value.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::FlashPower</code></td><td class="topAlign tblval"><code>4</code></td><td class="topAlign">Manual flash power, specified as qreal value. Accepted power range is [0..1.0], with 0 value means no flash and 1.0 corresponds to full flash power.</td></tr>
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<p>This value is only used in the <a href="qcameraexposure.html#FlashMode-enum">manual flash mode</a>.</p>
<div class="table"><table class="valuelist"><tr valign="top" class="even"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::TorchPower</code></td><td class="topAlign tblval"><code>6</code></td><td class="topAlign">Manual torch power, specified as qreal value. Accepted power range is [0..1.0], with 0 value means no light and 1.0 corresponds to full torch power.</td></tr>
</table></div>
<p>This value is only used in the <a href="qcameraexposure.html#FlashMode-enum">torch flash mode</a>.</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::FlashCompensation</code></td><td class="topAlign tblval"><code>5</code></td><td class="topAlign">Flash compensation, specified as qreal EV value.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::SpotMeteringPoint</code></td><td class="topAlign tblval"><code>7</code></td><td class="topAlign">The relative frame coordinate of the point to use for exposure metering in spot metering mode, specified as a QPointF.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::ExposureMode</code></td><td class="topAlign tblval"><code>8</code></td><td class="topAlign">Camera exposure mode.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::MeteringMode</code></td><td class="topAlign tblval"><code>9</code></td><td class="topAlign">Camera metering mode.</td></tr>
<tr><td class="topAlign"><code>QCameraExposureControl::ExtendedExposureParameter</code></td><td class="topAlign tblval"><code>1000</code></td><td class="topAlign">The base value for platform specific extended parameters. For such parameters the sequential values starting from ExtendedExposureParameter should be used.</td></tr>
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<h2>Member Function Documentation</h2>
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<h3 class="fn" id="QCameraExposureControl"><a name="QCameraExposureControl"></a><code>[protected] </code>QCameraExposureControl::<span class="name">QCameraExposureControl</span>(<span class="type">QObject</span> *<i>parent</i> = nullptr)</h3>
<p>Constructs a camera exposure control object with <i>parent</i>.</p>
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<h3 class="fn" id="dtor.QCameraExposureControl"><a name="dtor.QCameraExposureControl"></a><code>[virtual] </code>QCameraExposureControl::<span class="name">~QCameraExposureControl</span>()</h3>
<p>Destroys the camera exposure control object.</p>
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<h3 class="fn" id="actualValue"><a name="actualValue"></a><code>[pure virtual] </code><span class="type">QVariant</span> QCameraExposureControl::<span class="name">actualValue</span>(<span class="type"><a href="qcameraexposurecontrol.html#ExposureParameter-enum">QCameraExposureControl::ExposureParameter</a></span> <i>parameter</i>) const</h3>
<p>Returns the actual exposure <i>parameter</i> value, or invalid QVariant() if the value is unknown or not supported.</p>
<p>The actual parameter value may differ for the requested one if automatic mode is selected or camera supports only limited set of values within the supported range.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="actualValueChanged"><a name="actualValueChanged"></a><code>[signal] </code><span class="type">void</span> QCameraExposureControl::<span class="name">actualValueChanged</span>(<span class="type">int</span> <i>parameter</i>)</h3>
<p>Signal emitted when the actual exposure <i>parameter</i> value has changed, usually in result of auto exposure algorithms or manual exposure parameter applied.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="isParameterSupported"><a name="isParameterSupported"></a><code>[pure virtual] </code><span class="type">bool</span> QCameraExposureControl::<span class="name">isParameterSupported</span>(<span class="type"><a href="qcameraexposurecontrol.html#ExposureParameter-enum">QCameraExposureControl::ExposureParameter</a></span> <i>parameter</i>) const</h3>
<p>Returns true is exposure <i>parameter</i> is supported by backend.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="parameterRangeChanged"><a name="parameterRangeChanged"></a><code>[signal] </code><span class="type">void</span> QCameraExposureControl::<span class="name">parameterRangeChanged</span>(<span class="type">int</span> <i>parameter</i>)</h3>
<p>Signal emitted when the supported range of exposure <i>parameter</i> values has changed.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="requestedValue"><a name="requestedValue"></a><code>[pure virtual] </code><span class="type">QVariant</span> QCameraExposureControl::<span class="name">requestedValue</span>(<span class="type"><a href="qcameraexposurecontrol.html#ExposureParameter-enum">QCameraExposureControl::ExposureParameter</a></span> <i>parameter</i>) const</h3>
<p>Returns the requested exposure <i>parameter</i> value.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="requestedValueChanged"><a name="requestedValueChanged"></a><code>[signal] </code><span class="type">void</span> QCameraExposureControl::<span class="name">requestedValueChanged</span>(<span class="type">int</span> <i>parameter</i>)</h3>
<p>Signal emitted when the requested exposure <i>parameter</i> value has changed, usually in result of <a href="qcameraexposurecontrol.html#setValue">setValue</a>() call.</p>
<p>This function was introduced in Qt 5.0.</p>
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<h3 class="fn" id="setValue"><a name="setValue"></a><code>[pure virtual] </code><span class="type">bool</span> QCameraExposureControl::<span class="name">setValue</span>(<span class="type"><a href="qcameraexposurecontrol.html#ExposureParameter-enum">QCameraExposureControl::ExposureParameter</a></span> <i>parameter</i>, const <span class="type">QVariant</span> &<i>value</i>)</h3>
<p>Set the exposure <i>parameter</i> to <i>value</i>. If a null or invalid QVariant is passed, backend should choose the value automatically, and if possible report the actual value to user with <a href="qcameraexposurecontrol.html#actualValue">QCameraExposureControl::actualValue</a>().</p>
<p>Returns true if parameter is supported and value is correct.</p>
<p>This function was introduced in Qt 5.0.</p>
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<!-- $$$supportedParameterRange[overload1]$$$supportedParameterRangeQCameraExposureControl::ExposureParameterbool* -->
<h3 class="fn" id="supportedParameterRange"><a name="supportedParameterRange"></a><code>[pure virtual] </code><span class="type">QVariantList</span> QCameraExposureControl::<span class="name">supportedParameterRange</span>(<span class="type"><a href="qcameraexposurecontrol.html#ExposureParameter-enum">QCameraExposureControl::ExposureParameter</a></span> <i>parameter</i>, <span class="type">bool</span> *<i>continuous</i>) const</h3>
<p>Returns the list of supported <i>parameter</i> values;</p>
<p>If the camera supports arbitrary exposure parameter value within the supported range, *<i>continuous</i> is set to true, otherwise *<i>continuous</i> is set to false.</p>
<p>This function was introduced in Qt 5.0.</p>
<!-- @@@supportedParameterRange -->
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<div class="macros">
<h2>Macro Documentation</h2>
<!-- $$$QCameraExposureControl_iid[overload1]$$$QCameraExposureControl_iid -->
<h3 class="fn" id="QCameraExposureControl_iid"><a name="QCameraExposureControl_iid"></a><span class="name">QCameraExposureControl_iid</span></h3>
<p><code>org.qt-project.qt.cameraexposurecontrol/5.0</code></p>
<p>Defines the interface name of the <a href="qcameraexposurecontrol.html">QCameraExposureControl</a> class.</p>
<!-- @@@QCameraExposureControl_iid -->
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