Class for reading JPEG image data. More...

#include <GnashImageJpeg.h>

Inheritance diagram for gnash::image::JpegInput:

Public Member Functions
DSOEXPORT	JpegInput (std::shared_ptr< IOChannel > in)
	Construct a JpegInput object to read from an IOChannel. More...

void DSOEXPORT	readHeader (unsigned int maxHeaderBytes)
	Read the JPEG header information only. More...

	~JpegInput ()

void	read ()
	Begin processing the image data. More...

DSOEXPORT void	discardPartialBuffer ()
	Discard any data sitting in our input buffer. More...

void	finishImage ()
	Complete processing the image and clean up. More...

size_t	getHeight () const
	Get the image's height in pixels. More...

size_t	getWidth () const
	Get the image's width in pixels. More...

size_t	getComponents () const
	Get number of components (channels) More...

void	readScanline (unsigned char *rgbData)
	Read a scanline's worth of image data into the given buffer. More...

void	errorOccurred (const char *msg)
	This function is called when libjpeg encounters an error. More...

Public Member Functions inherited from gnash::image::Input
	Input (std::shared_ptr< IOChannel > in)
	Construct an Input object to read from an IOChannel. More...

virtual	~Input ()

ImageType	imageType ()
	Get the ImageType of the image. More...

Static Public Member Functions
static std::unique_ptr< Input >	create (std::shared_ptr< IOChannel > in)
	Create a JpegInput and transfer ownership to the caller. More...

static DSOEXPORT std::unique_ptr< GnashImage >	readSWFJpeg2WithTables (JpegInput &loader)
	For reading SWF JPEG2-style image data, using pre-loaded headers stored in the given JpegInput object. More...

static std::unique_ptr< JpegInput >	createSWFJpeg2HeaderOnly (std::shared_ptr< IOChannel > in, unsigned int maxHeaderBytes)
	Create a JPEG 'loader' object by reading a JPEG header. More...

Static Public Member Functions inherited from gnash::image::Input
static DSOEXPORT std::unique_ptr< ImageRGBA >	readSWFJpeg3 (std::shared_ptr< gnash::IOChannel > in)
	For reading SWF JPEG3-style image data, like ordinary JPEG, but stores the data in ImageRGBA format. More...

static DSOEXPORT std::unique_ptr< GnashImage >	readImageData (std::shared_ptr< gnash::IOChannel > in, FileType type)
	Read image data from an IOChannel into an GnashImage. More...

Additional Inherited Members
Protected Attributes inherited from gnash::image::Input
std::shared_ptr< IOChannel >	_inStream

ImageType	_type

Detailed Description

Class for reading JPEG image data.

This uses the IJG jpeglib to implement the Input interface.

Constructor & Destructor Documentation

§ JpegInput()

gnash::image::JpegInput::JpegInput ( std::shared_ptr< IOChannel > in )

Construct a JpegInput object to read from an IOChannel.

Parameters

in	The stream to read JPEG data from. Ownership is shared between caller and JpegInput, so it is freed automatically when the last owner is destroyed.

§ ~JpegInput()

gnash::image::JpegInput::~JpegInput ( )

Member Function Documentation

§ create()

static std::unique_ptr<Input> gnash::image::JpegInput::create ( std::shared_ptr< IOChannel > in )

inlinestatic

Create a JpegInput and transfer ownership to the caller.

Parameters

in	The IOChannel to read JPEG data from.

References DSOEXPORT.

Referenced by gnash::image::Input::readImageData().

§ createSWFJpeg2HeaderOnly()

static std::unique_ptr<JpegInput> gnash::image::JpegInput::createSWFJpeg2HeaderOnly	(	std::shared_ptr< IOChannel >	in,
		unsigned int	maxHeaderBytes
	)

inlinestatic

Create a JPEG 'loader' object by reading a JPEG header.

This is for reusing the header information for different JPEGs images.

Parameters

in	The channel to read JPEG header data from.
maxHeaderBytes	The maximum number of bytes to read.

Referenced by gnash::image::Input::readSWFJpeg3().

§ discardPartialBuffer()

void gnash::image::JpegInput::discardPartialBuffer ( )

Discard any data sitting in our input buffer.

Use this before/after reading headers or partial image data, to avoid screwing up future reads.

Referenced by gnash::SWF::DefineBitsTag::loader().

§ errorOccurred()

void gnash::image::JpegInput::errorOccurred ( const char * msg )

This function is called when libjpeg encounters an error.

It is needed to avoid memory corruption during stack unwinding by freeing libjpeg resources correctly before throwing an exception.

Parameters

msg	An error message for logging.

References gnash::log_error().

§ finishImage()

void gnash::image::JpegInput::finishImage ( )

Complete processing the image and clean up.

This should close / free all resources from libjpeg.

References _.

Referenced by readSWFJpeg2WithTables().

§ getComponents()

size_t gnash::image::JpegInput::getComponents ( ) const

virtual

Get number of components (channels)

Returns: The number of components, e.g. 3 for RGB

Implements gnash::image::Input.

Referenced by read().

§ getHeight()

size_t gnash::image::JpegInput::getHeight ( ) const

virtual

Get the image's height in pixels.

Returns: The height of the image in pixels.

Implements gnash::image::Input.

Referenced by readSWFJpeg2WithTables().

§ getWidth()

size_t gnash::image::JpegInput::getWidth ( ) const

virtual

Get the image's width in pixels.

Returns: The width of the image in pixels.

Implements gnash::image::Input.

Referenced by readScanline(), and readSWFJpeg2WithTables().

§ read()

void gnash::image::JpegInput::read ( )

virtual

Begin processing the image data.

Implements gnash::image::Input.

References _, gnash::image::Input::_type, getComponents(), gnash::log_error(), gnash::image::TYPE_RGB, and gnash::image::TYPE_RGBA.

Referenced by readSWFJpeg2WithTables().

§ readHeader()

void gnash::image::JpegInput::readHeader ( unsigned int maxHeaderBytes )

Read the JPEG header information only.

Parameters

maxHeaderBytes The maximum number of bytes to read before Stopping. If the header is shorter, we stop early.

References _, and gnash::log_error().

§ readScanline()

void gnash::image::JpegInput::readScanline ( unsigned char * rgbData )

virtual

Read a scanline's worth of image data into the given buffer.

The amount of data read is getWidth() * getComponents().

Parameters

rgbData The buffer for writing raw RGB data to.

Implements gnash::image::Input.

References getWidth(), and test::w.

Referenced by readSWFJpeg2WithTables().

§ readSWFJpeg2WithTables()

std::unique_ptr< GnashImage > gnash::image::JpegInput::readSWFJpeg2WithTables ( JpegInput & loader )

static

For reading SWF JPEG2-style image data, using pre-loaded headers stored in the given JpegInput object.

Parameters

loader The JpegInput object to use for reading the data. This should have been constructed with createSWFJpeg2HeaderOnly().

References finishImage(), getHeight(), getWidth(), height, read(), readScanline(), gnash::image::scanline(), and y.

Referenced by gnash::SWF::DefineBitsTag::loader().

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

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

§ JpegInput()

§ ~JpegInput()

Member Function Documentation

§ create()

§ createSWFJpeg2HeaderOnly()

§ discardPartialBuffer()

§ errorOccurred()

§ finishImage()

§ getComponents()

§ getHeight()

§ getWidth()

§ read()

§ readHeader()

§ readScanline()

§ readSWFJpeg2WithTables()