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<h1 align=center>QImageFormatType Class Reference</h1><br clear="all">
<p>
Factory that makes <a href="qimageformat.html">QImageFormat</a> objects.
<a href="#details">More...</a>
<p>
<code>#include <<a href="qasyncimageio-h.html">qasyncimageio.h</a>></code>
<p><a href="qimageformattype-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><span class="fn">virtual<a href="qimageformattype.html#a0"><strong>~QImageFormatType</strong></a>()</span>
<li><span class="fn">virtualQImageFormat*<a href="qimageformattype.html#a1"><strong>decoderFor</strong></a>(constuchar*buffer, intlength)</span>
<li><span class="fn">virtualconstchar*<a href="qimageformattype.html#a2"><strong>formatName</strong></a>()const</span>
</ul>
<h2>Protected Members</h2>
<ul>
<li><span class="fn"><a href="qimageformattype.html#a3"><strong>QImageFormatType</strong></a>()</span>
</ul>
<hr><h2><a name="details"></a>Detailed Description</h2>
Factory that makes <a href="qimageformat.html">QImageFormat</a> objects.
<p>
While the <a href="qimageio.html">QImageIO</a> class allows for <em>complete</em> loading of images,
QImageFormatType allows for <em>incremental</em> loading of images.
<p>New image file formats are installed by creating objects of derived
classes of QImageFormatType. They must implement <a href="qimageformattype.html#a1">decoderFor</a>()
and <a href="qimageformattype.html#a2">formatName</a>().
<p>QImageFormatType is a very simple class. Its only task is to
recognize image data in some format and make a new object, subclassed
from QImageFormat, which can decode that format.
<p>The factories for formats built into Qt
are automatically defined before any other factory is initialized.
If two factories would recognize an image format, the factory created
last will override the earlier one, thus you can override current
and future built-in formats.
<hr><h2>Member Function Documentation</h2>
<h3 class="fn"><a name="a3"></a>QImageFormatType::QImageFormatType() <code>[protected]</code></h3>
<p>Creates a factory. It automatically registers itself with <a href="qimagedecoder.html">QImageDecoder</a>.
<h3 class="fn"><a name="a0"></a>QImageFormatType::~QImageFormatType() <code>[virtual]</code></h3>
<p>Destroys a factory. It automatically unregisters itself from <a href="qimagedecoder.html">QImageDecoder</a>.
<h3 class="fn">virtual<a href="qimageformat.html">QImageFormat</a>*<a name="a1"></a>QImageFormatType::decoderFor(constuchar*buffer, intlength) <code>[virtual]</code></h3>
<p>Returns a decoder for decoding an image which starts with the give bytes.
This function should only return a decoder if it is definate that the
decoder applies to data with the given header. Returns 0 if there is
insufficient data in the header to make a positive identification,
or if the data is not recognized.
<h3 class="fn">virtualconstchar*<a name="a2"></a>QImageFormatType::formatName()const <code>[virtual]</code></h3>
<p>Returns the name of the format supported by decoders from this factory.
The string is statically allocated.
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This file is part of the <a href="index.html">Qt toolkit</a>,
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It was generated from the following files:
<ul>
<li>qasyncimageio.h: 1999/02/12
<li>qasyncimageio.cpp: 1999/02/13
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