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<h1 class="title">Reading and Writing Image Files</h1>
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<p>The most common way to read images is through <a href="qimage.html">QImage</a> and <a href="qpixmap.html">QPixmap</a>'s constructors, or by calling the <a href="qimage.html#load">QImage::load</a>() and <a href="qpixmap.html#load">QPixmap::load</a>() functions. In addition, Qt provides the <a href="qimagereader.html">QImageReader</a> class which gives more control over the process. Depending on the underlying support in the image format, the functions provided by the class can save memory and speed up loading of images.</p>
<p>Likewise, Qt provides the <a href="qimagewriter.html">QImageWriter</a> class which supports setting format specific options, such as the gamma level, compression level and quality, prior to storing the image. If you do not need such options, you can use <a href="qimage.html#save">QImage::save</a>() or <a href="qpixmap.html#save">QPixmap::save</a>() instead.</p>
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<tr valign="top" class="odd"><td ><b>QMovie</b><p><a href="qmovie.html">QMovie</a> is a convenience class for displaying animations, using the <a href="qimagereader.html">QImageReader</a> class internally. Once created, the <a href="qmovie.html">QMovie</a> class provides various functions for both running and controlling the given animation.</p>
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<p>The <a href="qimagereader.html">QImageReader</a> and <a href="qimagewriter.html">QImageWriter</a> classes rely on the <a href="qimageiohandler.html">QImageIOHandler</a> class which is the common image I/O interface for all image formats in Qt. <a href="qimageiohandler.html">QImageIOHandler</a> objects are used internally by <a href="qimagereader.html">QImageReader</a> and <a href="qimagewriter.html">QImageWriter</a> to add support for different image formats to Qt.</p>
<p>A list of the supported file formats are available through the <a href="qimagereader.html#supportedImageFormats">QImageReader::supportedImageFormats</a>() and <a href="qimagewriter.html#supportedImageFormats">QImageWriter::supportedImageFormats</a>() functions. Qt supports several file formats by default, and in addition new formats can be added as plugins. The currently supported formats are listed in the <a href="qimagereader.html">QImageReader</a> and <a href="qimagewriter.html">QImageWriter</a> class documentation.</p>
<p>Qt's plugin mechanism can also be used to write a custom image format handler. This is done by deriving from the <a href="qimageiohandler.html">QImageIOHandler</a> class, and creating a <a href="qimageioplugin.html">QImageIOPlugin</a> object which is a factory for creating <a href="qimageiohandler.html">QImageIOHandler</a> objects. When the plugin is installed, <a href="qimagereader.html">QImageReader</a> and <a href="qimagewriter.html">QImageWriter</a> will automatically load the plugin and start using it.</p>
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armv5tl
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media
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