QImageFormatType(3qt)QImageFormatType(3qt)NAME
QImageFormatType - Factory that makes QImageFormat objects
SYNOPSIS
#include <qasyncimageio.h>
Public Members
virtual ~QImageFormatType ()
virtual QImageFormat * decoderFor ( const uchar * buffer, int length )
= 0
virtual const char * formatName () const = 0
Protected Members
QImageFormatType ()
DESCRIPTION
The QImageFormatType class is a factory that makes QImageFormat
objects.
Whereas the QImageIO class allows for complete loading of images,
QImageFormatType allows for incremental loading of images.
New image file formats are installed by creating objects of derived
classes of QImageFormatType. They must implement decoderFor() and
formatName().
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.
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; you can thus override current and future built-in formats.
See also Graphics Classes, Image Processing Classes, and Multimedia
Classes.
MEMBER FUNCTION DOCUMENTATIONQImageFormatType::QImageFormatType () [protected]
Constructs a factory. It automatically registers itself with
QImageDecoder.
QImageFormatType::~QImageFormatType () [virtual]
Destroys a factory. It automatically unregisters itself from
QImageDecoder.
QImageFormat * QImageFormatType::decoderFor ( const uchar * buffer, int length
) [pure virtual]
Returns a decoder for decoding an image that starts with the bytes in
buffer. The length of the data is given in length. This function should
only return a decoder if it is certain 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.
const char * QImageFormatType::formatName () const [pure virtual]
Returns the name of the format supported by decoders from this factory.
The string is statically allocated.
SEE ALSO
http://doc.trolltech.com/qimageformattype.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
license file included in the distribution for a complete license
statement.
AUTHOR
Generated automatically from the source code.
BUGS
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bugs@trolltech.com. Please include the name of the manual page
(qimageformattype.3qt) and the Qt version (3.3.8).
Trolltech AS 2 February 2007 QImageFormatType(3qt)