/usr/share/qt5/doc/qtgraphicaleffects/qml-qtgraphicaleffects-gammaadjust.html is in qtgraphicaleffects5-doc-html 5.2.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 | <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en_US" lang="en_US">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!-- GammaAdjust.qml -->
<title>GammaAdjust | QtGraphicalEffects 5.2</title>
<link rel="stylesheet" type="text/css" href="style/offline.css" />
</head>
<body>
<div class="header" id="qtdocheader">
<div class="main">
<div class="main-rounded">
<div class="navigationbar">
<ul>
<li>Qt 5.2</li>
<li><a href="qtgraphicaleffects-index.html">Qt Graphical Effects</a></li>
<li><a href="graphicaleffects.html">QML Types</a></li>
<li>GammaAdjust</li>
<li id="buildversion">
Qt 5.2.1 Reference Documentation</li>
</ul>
</div>
</div>
<div class="content">
<div class="line">
<div class="content mainContent">
<div class="toc">
<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#properties">Properties</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
<li class="level2"><a href="#example">Example</a></li>
</ul>
</div>
<h1 class="title">GammaAdjust</h1>
<span class="subtitle"></span>
<!-- $$$GammaAdjust-brief -->
<p>Alters the luminance of the source item. <a href="#details">More...</a></p>
<!-- @@@GammaAdjust -->
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Import Statement:</td><td class="memItemRight bottomAlign"> </b><tt>import QtGraphicalEffects 1.0</tt></td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> QtGraphicalEffects 1.0</td></tr></table><ul>
<li><a href="qml-qtgraphicaleffects-gammaadjust-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="properties"></a>
<h2>Properties</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-gammaadjust.html#cached-prop">cached</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-gammaadjust.html#gamma-prop">gamma</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-gammaadjust.html#source-prop">source</a></b></b> : variant</li>
</ul>
<!-- $$$GammaAdjust-description -->
<a name="details"></a>
<h2>Detailed Description</h2>
<p>GammaAdjust is applied to each pixel according to the curve which is pre-defined as a power-law expression, where the property gamma is used as the reciprocal scaling exponent. Refer to the property documentation of <a href="qml-qtgraphicaleffects-gammaadjust.html#gamma-prop">gamma</a> for more details.</p>
<table class="generic">
<thead><tr class="qt-style"><th >Source</th><th >Effect applied</th></tr></thead>
<tr valign="top" class="odd"><td ><p class="centerAlign"><img src="images/Original_bug.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/GammaAdjust_bug.png" alt="" /></p></td></tr>
</table>
<a name="example"></a>
<h2>Example</h2>
<p>The following example shows how to apply the effect.</p>
<pre class="qml">import QtQuick 2.0
import QtGraphicalEffects 1.0
<span class="type">Item</span> {
<span class="name">width</span>: <span class="number">300</span>
<span class="name">height</span>: <span class="number">300</span>
<span class="type">Image</span> {
<span class="name">id</span>: <span class="name">bug</span>
<span class="name">source</span>: <span class="string">"images/bug.jpg"</span>
<span class="name">sourceSize</span>: <span class="name">Qt</span>.<span class="name">size</span>(<span class="name">parent</span>.<span class="name">width</span>, <span class="name">parent</span>.<span class="name">height</span>)
<span class="name">smooth</span>: <span class="number">true</span>
<span class="name">visible</span>: <span class="number">false</span>
}
<span class="type">GammaAdjust</span> {
<span class="name">anchors</span>.fill: <span class="name">bug</span>
<span class="name">source</span>: <span class="name">bug</span>
<span class="name">gamma</span>: <span class="number">0.45</span>
}
}</pre>
<!-- @@@GammaAdjust -->
<h2>Property Documentation</h2>
<!-- $$$cached -->
<div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="cached-prop"></a><span class="name">cached</span> : <span class="type">bool</span></p></td></tr></table></div><div class="qmldoc"><p>This property allows the effect output pixels to be cached in order to improve the rendering performance.</p>
<p>Every time the source or effect properties are changed, the pixels in the cache must be updated. Memory consumption is increased, because an extra buffer of memory is required for storing the effect output.</p>
<p>It is recommended to disable the cache when the source or the effect properties are animated.</p>
<p>By default, the property is set to <tt>false</tt>.</p>
</div></div><!-- @@@cached -->
<br/>
<!-- $$$gamma -->
<div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="gamma-prop"></a><span class="name">gamma</span> : <span class="type">real</span></p></td></tr></table></div><div class="qmldoc"><p>This property defines the change factor for how the luminance of each pixel is altered according to the equation:</p>
<pre class="cpp">luminance <span class="operator">=</span> pow(original_luminance<span class="operator">,</span> <span class="number">1.0</span> <span class="operator">/</span> gamma); <span class="comment">// The luminance is assumed to be between 0.0 and 1.0</span></pre>
<p>Setting the gamma values under 1.0 makes the image darker, the values above 1.0 lighten it.</p>
<p>The value ranges from 0.0 (darkest) to inf (lightest). By default, the property is set to <tt>1.0</tt> (no change).</p>
<table class="generic">
<thead><tr class="qt-style"><th >Output examples with different gamma values</th><th ></th><th ></th></tr></thead>
<tr valign="top" class="odd"><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma1.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma2.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma3.png" alt="" /></p></td></tr>
<tr valign="top" class="even"><td ><b> gamma: 0.5 </b></td><td ><b> gamma: 1.0 </b></td><td ><b> gamma: 2.0 </b></td></tr>
</table>
<table class="generic">
<thead><tr class="qt-style"><th >Pixel luminance curves of the above images.</th><th ></th><th ></th></tr></thead>
<tr valign="top" class="odd"><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma1_graph.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma2_graph.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/GammaAdjust_gamma3_graph.png" alt="" /></p></td></tr>
<tr valign="top" class="even"><td >Red curve: default gamma (1.0)</td><td ></td><td ></td></tr>
<tr valign="top" class="odd"><td >Yellow curve: effect applied</td><td ></td><td ></td></tr>
<tr valign="top" class="even"><td >X-axis: pixel original luminance</td><td ></td><td ></td></tr>
<tr valign="top" class="odd"><td >Y-axis: pixel luminance with effect applied</td><td ></td><td ></td></tr>
</table>
</div></div><!-- @@@gamma -->
<br/>
<!-- $$$source -->
<div class="qmlitem"><div class="qmlproto"><table class="qmlname"><tr valign="top" class="odd"><td class="tblQmlPropNode"><p><a name="source-prop"></a><span class="name">source</span> : <span class="type">variant</span></p></td></tr></table></div><div class="qmldoc"><p>This property defines the source item for which the luminance is going to be adjusted.</p>
<p><b>Note: </b>It is not supported to let the effect include itself, for instance by setting source to the effect's parent.</p></div></div><!-- @@@source -->
<br/>
</div>
</div>
</div>
</div>
</div>
<div class="footer">
<p>
<acronym title="Copyright">©</acronym> 2013 Digia Plc and/or its
subsidiaries. Documentation contributions included herein are the copyrights of
their respective owners.<br> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br> Digia, Qt and their respective logos are trademarks of Digia Plc in Finland and/or other countries worldwide. All other trademarks are property
of their respective owners. </p>
</div>
</body>
</html>
|