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Public Member Functions | Static Public Member Functions | List of all members
QWebpHandler Class Reference

#include <qwebphandler_p.h>

+ Inheritance diagram for QWebpHandler:
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Public Member Functions

 QWebpHandler ()
 
 ~QWebpHandler ()
 
bool canRead () const override
 Returns true if an image can be read from the device (i.e., the image format is supported, the device can be read from and the initial header information suggests that the image can be read); otherwise returns false.
 
bool read (QImage *image) override
 Read an image from the device, and stores it in image.
 
bool write (const QImage &image) override
 Writes the image image to the assigned device.
 
QVariant option (ImageOption option) const override
 Returns the value assigned to option as a QVariant.
 
void setOption (ImageOption option, const QVariant &value) override
 Sets the option option with the value value.
 
bool supportsOption (ImageOption option) const override
 Returns true if the QImageIOHandler supports the option option; otherwise returns false.
 
int imageCount () const override
 For image formats that support animation, this function returns the number of images in the animation.
 
int currentImageNumber () const override
 For image formats that support animation, this function returns the sequence number of the current image in the animation.
 
QRect currentImageRect () const override
 Returns the rect of the current image.
 
int loopCount () const override
 For image formats that support animation, this function returns the number of times the animation should loop.
 
int nextImageDelay () const override
 For image formats that support animation, this function returns the number of milliseconds to wait until reading the next image.
 
- Public Member Functions inherited from QImageIOHandler
 QImageIOHandler ()
 Constructs a QImageIOHandler object.
 
virtual ~QImageIOHandler ()
 Destructs the QImageIOHandler object.
 
void setDevice (QIODevice *device)
 Sets the device of the QImageIOHandler to device.
 
QIODevice * device () const
 Returns the device currently assigned to the QImageIOHandler.
 
void setFormat (const QByteArray &format)
 Sets the format of the QImageIOHandler to format.
 
void setFormat (const QByteArray &format) const
 Sets the format of the QImageIOHandler to format.
 
QByteArray format () const
 Returns the format that is currently assigned to QImageIOHandler.
 
virtual bool jumpToNextImage ()
 For image formats that support animation, this function jumps to the next image.
 
virtual bool jumpToImage (int imageNumber)
 For image formats that support animation, this function jumps to the image whose sequence number is imageNumber.
 

Static Public Member Functions

static bool canRead (QIODevice *device)
 
- Static Public Member Functions inherited from QImageIOHandler
static bool allocateImage (QSize size, QImage::Format format, QImage *image)
 

Additional Inherited Members

- Public Types inherited from QImageIOHandler
enum  ImageOption {
  Size , ClipRect , Description , ScaledClipRect ,
  ScaledSize , CompressionRatio , Gamma , Quality ,
  Name , SubType , IncrementalReading , Endianness ,
  Animation , BackgroundColor , ImageFormat , SupportedSubTypes ,
  OptimizedWrite , ProgressiveScanWrite , ImageTransformation
}
 This enum describes the different options supported by QImageIOHandler. More...
 
enum  Transformation {
  TransformationNone = 0 , TransformationMirror = 1 , TransformationFlip = 2 , TransformationRotate180 = TransformationMirror | TransformationFlip ,
  TransformationRotate90 = 4 , TransformationMirrorAndRotate90 = TransformationMirror | TransformationRotate90 , TransformationFlipAndRotate90 = TransformationFlip | TransformationRotate90 , TransformationRotate270 = TransformationRotate180 | TransformationRotate90
}
 
- Protected Member Functions inherited from QImageIOHandler
 QImageIOHandler (QImageIOHandlerPrivate &dd)
 
- Protected Attributes inherited from QImageIOHandler
QScopedPointer< QImageIOHandlerPrivate > d_ptr
 

Detailed Description

Definition at line 17 of file qwebphandler_p.h.

Constructor & Destructor Documentation

◆ QWebpHandler()

QWebpHandler::QWebpHandler ( )

Definition at line 16 of file qwebphandler.cpp.

◆ ~QWebpHandler()

QWebpHandler::~QWebpHandler ( )

Definition at line 29 of file qwebphandler.cpp.

Member Function Documentation

◆ canRead() [1/2]

bool QWebpHandler::canRead ( ) const
overridevirtual

Returns true if an image can be read from the device (i.e., the image format is supported, the device can be read from and the initial header information suggests that the image can be read); otherwise returns false.

When reimplementing canRead(), make sure that the I/O device (device()) is left in its original state (e.g., by using peek() rather than read()).

See also
read(), QIODevice::peek()

Implements QImageIOHandler.

Definition at line 36 of file qwebphandler.cpp.

References canRead(), QImageIOHandler::device(), QByteArrayLiteral, and QImageIOHandler::setFormat().

Referenced by canRead(), and QWebpPlugin::capabilities().

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◆ canRead() [2/2]

bool QWebpHandler::canRead ( QIODevice * device)
static

Definition at line 52 of file qwebphandler.cpp.

References QImageIOHandler::device(), header(), QIODevice::peek(), qWarning, and riffHeaderSize.

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◆ currentImageNumber()

int QWebpHandler::currentImageNumber ( ) const
overridevirtual

For image formats that support animation, this function returns the sequence number of the current image in the animation.

If this function is called before any image is read(), -1 is returned. The number of the first image in the sequence is 0.

If the image format does not support animation, 0 is returned.

See also
read()

Reimplemented from QImageIOHandler.

Definition at line 366 of file qwebphandler.cpp.

◆ currentImageRect()

QRect QWebpHandler::currentImageRect ( ) const
overridevirtual

Returns the rect of the current image.

If no rect is defined for the image, and empty QRect() is returned.

This function is useful for animations, where only parts of the frame may be updated at a time.

Reimplemented from QImageIOHandler.

Definition at line 375 of file qwebphandler.cpp.

Referenced by read().

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◆ imageCount()

int QWebpHandler::imageCount ( ) const
overridevirtual

For image formats that support animation, this function returns the number of images in the animation.

If the image format does not support animation, or if it is unable to determine the number of images, 0 is returned.

The default implementation returns 1 if canRead() returns true; otherwise 0 is returned.

Reimplemented from QImageIOHandler.

Definition at line 355 of file qwebphandler.cpp.

◆ loopCount()

int QWebpHandler::loopCount ( ) const
overridevirtual

For image formats that support animation, this function returns the number of times the animation should loop.

If the image format does not support animation, 0 is returned.

Reimplemented from QImageIOHandler.

Definition at line 383 of file qwebphandler.cpp.

◆ nextImageDelay()

int QWebpHandler::nextImageDelay ( ) const
overridevirtual

For image formats that support animation, this function returns the number of milliseconds to wait until reading the next image.

If the image format does not support animation, 0 is returned.

Reimplemented from QImageIOHandler.

Definition at line 392 of file qwebphandler.cpp.

◆ option()

QVariant QWebpHandler::option ( ImageOption option) const
overridevirtual

Returns the value assigned to option as a QVariant.

The type of the value depends on the option. For example, option(Size) returns a QSize variant.

See also
setOption(), supportsOption()

Reimplemented from QImageIOHandler.

Definition at line 316 of file qwebphandler.cpp.

References QImageIOHandler::Animation, QImageIOHandler::BackgroundColor, QImageIOHandler::Quality, QImageIOHandler::Size, and supportsOption().

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◆ read()

bool QWebpHandler::read ( QImage * image)
overridevirtual

Read an image from the device, and stores it in image.

Returns true if the image is successfully read; otherwise returns false.

For image formats that support incremental loading, and for animation formats, the image handler can assume that image points to the previous frame.

See also
canRead()

Implements QImageIOHandler.

Definition at line 126 of file qwebphandler.cpp.

References QImageIOHandler::allocateImage(), Qt::black, QPainter::CompositionMode_Clear, QPainter::CompositionMode_Source, QPainter::CompositionMode_SourceOver, QByteArray::constData(), currentImageRect(), QByteArray::detach(), QPainter::drawImage(), QPainter::fillRect(), QImage::Format_ARGB32, QImage::Format_RGB32, frame, QColorSpace::fromIccProfile(), QByteArray::fromRawData(), output, painter, and QPainter::setCompositionMode().

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◆ setOption()

void QWebpHandler::setOption ( ImageOption option,
const QVariant & value )
overridevirtual

Sets the option option with the value value.

See also
option(), ImageOption

Reimplemented from QImageIOHandler.

Definition at line 335 of file qwebphandler.cpp.

References QImageIOHandler::Quality, and QImageIOHandler::setOption().

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◆ supportsOption()

bool QWebpHandler::supportsOption ( ImageOption option) const
overridevirtual

Returns true if the QImageIOHandler supports the option option; otherwise returns false.

For example, if the QImageIOHandler supports the \l Size option, supportsOption(Size) must return true.

See also
setOption(), option()

Reimplemented from QImageIOHandler.

Definition at line 347 of file qwebphandler.cpp.

References QImageIOHandler::BackgroundColor, and QImageIOHandler::Quality.

Referenced by option().

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◆ write()

bool QWebpHandler::write ( const QImage & image)
overridevirtual

Writes the image image to the assigned device.

Returns true on success; otherwise returns false.

The default implementation does nothing, and simply returns false.

Reimplemented from QImageIOHandler.

Definition at line 205 of file qwebphandler.cpp.

References QByteArray::constData(), QImageIOHandler::device(), QImage::Format_RGB888, QImage::Format_RGBA8888, qMin(), qWarning, QByteArray::size(), and QIODevice::write().

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The documentation for this class was generated from the following files: