Class JPEGImageReader

java.lang.Object

javax.imageio.ImageReader

com.twelvemonkeys.imageio.ImageReaderBase

com.twelvemonkeys.imageio.plugins.jpeg.JPEGImageReader

public final class JPEGImageReader
extends ImageReaderBase

A JPEG ImageReader implementation based on the JRE JPEGImageReader, that adds support and properly handles cases where the JRE version throws exceptions.
Main features:

• Support for YCbCr JPEGs without JFIF segment (converted to RGB, using the embedded ICC profile if applicable)
• Support for CMYK JPEGs (converted to RGB by default or as CMYK, using the embedded ICC profile if applicable)
• Support for Adobe YCCK JPEGs (converted to RGB by default or as CMYK, using the embedded ICC profile if applicable)
• Support for JPEGs containing ICC profiles with interpretation other than 'Perceptual' (profile is assumed to be 'Perceptual' and used)
• Support for JPEGs containing ICC profiles with class other than 'Display' (profile is assumed to have class 'Display' and used)
• Support for JPEGs containing ICC profiles that are incompatible with stream data (image data is read, profile is ignored)
• Support for JPEGs with corrupted ICC profiles (image data is read, profile is ignored)
• Support for JPEGs with corrupted ICC_PROFILE segments (image data is read, profile is ignored)
• Support for JPEGs using non-standard color spaces, unsupported by Java 2D (image data is read, profile is ignored)
• Issues warnings instead of throwing exceptions in cases of corrupted data where ever the image data can still be read in a reasonable way

Thumbnail support:

• Support for JFIF thumbnails (even if stream contains inconsistent metadata)
• Support for JFXX thumbnails (JPEG, Indexed and RGB)
• Support for EXIF thumbnails (JPEG, RGB and YCbCr)

Metadata support:

• Support for JPEG metadata in both standard and native formats (even if stream contains inconsistent metadata)
• Support for javax_imageio_jpeg_image_1.0 format (currently as native format, may change in the future)
• Support for illegal combinations of JFIF, Exif and Adobe markers, using "unknown" segments in the "MarkerSequence" tag for the unsupported segments (for javax_imageio_jpeg_image_1.0 format)

Version:

$Id: JPEGImageReader.java,v 1.0 24.01.11 16.37 haraldk Exp$

Author:

Harald Kuhr, LUT-based YCbCR conversion by Werner Randelshofer, last modified by $Author: haraldk$

Field Summary

Fields inherited from class ImageReaderBase

imageInput

Fields inherited from class ImageReader

availableLocales, ignoreMetadata, input, locale, minIndex, originatingProvider, progressListeners, seekForwardOnly, updateListeners, warningListeners, warningLocales

Method Summary

Modifier and Type	Method	Description
void	abort()
boolean	canReadRaster()
void	dispose()
ImageReadParam	getDefaultReadParam()
String	getFormatName()
int	getHeight(int imageIndex)
IIOMetadata	getImageMetadata(int imageIndex)	Default implementation that always returns null.
Iterator<ImageTypeSpecifier>	getImageTypes(int imageIndex)
int	getNumImages(boolean allowSearch)	Default implementation that always returns 1.
int	getNumThumbnails(int imageIndex)
ImageTypeSpecifier	getRawImageType(int imageIndex)
IIOMetadata	getStreamMetadata()	Default implementation that always returns null.
int	getThumbnailHeight(int imageIndex, int thumbnailIndex)
int	getThumbnailWidth(int imageIndex, int thumbnailIndex)
int	getWidth(int imageIndex)
static void	main(String[] args)
protected void	processWarningOccurred(String warning)
BufferedImage	read(int imageIndex, ImageReadParam param)
RenderedImage	readAsRenderedImage(int imageIndex, ImageReadParam param)
boolean	readerSupportsThumbnails()
Raster	readRaster(int imageIndex, ImageReadParam param)
BufferedImage	readThumbnail(int imageIndex, int thumbnailIndex)
protected void	resetMembers()	Resets all member variables.
void	setInput(Object input, boolean seekForwardOnly, boolean ignoreMetadata)	Overrides setInput, to allow easy access to the input, in case it is an ImageInputStream.
protected static void	showIt(BufferedImage pImage, String pTitle)

Methods inherited from class ImageReaderBase

assertInput, checkBounds, fakeAOI, fakeSubsampling, getDestination, hasExplicitDestination, reset

Methods inherited from class ImageReader

abortRequested, addIIOReadProgressListener, addIIOReadUpdateListener, addIIOReadWarningListener, checkReadParamBandSettings, clearAbortRequest, computeRegions, getAspectRatio, getAvailableLocales, getImageMetadata, getInput, getLocale, getMinIndex, getOriginatingProvider, getSourceRegion, getStreamMetadata, getTileGridXOffset, getTileGridYOffset, getTileHeight, getTileWidth, hasThumbnails, isIgnoringMetadata, isImageTiled, isRandomAccessEasy, isSeekForwardOnly, processImageComplete, processImageProgress, processImageStarted, processImageUpdate, processPassComplete, processPassStarted, processReadAborted, processSequenceComplete, processSequenceStarted, processThumbnailComplete, processThumbnailPassComplete, processThumbnailPassStarted, processThumbnailProgress, processThumbnailStarted, processThumbnailUpdate, processWarningOccurred, read, readAll, readAll, readTile, readTileRaster, removeAllIIOReadProgressListeners, removeAllIIOReadUpdateListeners, removeAllIIOReadWarningListeners, removeIIOReadProgressListener, removeIIOReadUpdateListener, removeIIOReadWarningListener, setInput, setInput, setLocale

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

resetMembers

protected void resetMembers()

Description copied from class: ImageReaderBase

Resets all member variables. This method is by default invoked from:

• ImageReaderBase.setInput(Object, boolean, boolean)
• ImageReaderBase.dispose()
• ImageReaderBase.reset()

Specified by:

resetMembers in class ImageReaderBase

dispose

public void dispose()

Overrides:

dispose in class ImageReaderBase

getFormatName

public String getFormatName()
                     throws IOException

Overrides:

getFormatName in class ImageReader

Throws:

IOException

getWidth

public int getWidth(int imageIndex)
             throws IOException

Specified by:

getWidth in class ImageReader

Throws:

IOException

getHeight

public int getHeight(int imageIndex)
              throws IOException

Specified by:

getHeight in class ImageReader

Throws:

IOException

getImageTypes

public Iterator<ImageTypeSpecifier> getImageTypes(int imageIndex)
                                           throws IOException

Specified by:

getImageTypes in class ImageReader

Throws:

IOException

getRawImageType

public ImageTypeSpecifier getRawImageType(int imageIndex)
                                   throws IOException

Overrides:

getRawImageType in class ImageReader

Throws:

IOException

read

public BufferedImage read(int imageIndex,
 ImageReadParam param)
                   throws IOException

Specified by:

read in class ImageReader

Throws:

IOException

setInput

public void setInput(Object input,
 boolean seekForwardOnly,
 boolean ignoreMetadata)

Description copied from class: ImageReaderBase

Overrides setInput, to allow easy access to the input, in case it is an ImageInputStream.

Overrides:

setInput in class ImageReaderBase

Parameters:

input - the ImageInputStream or other Object to use for future decoding.

seekForwardOnly - if true, images and metadata may only be read in ascending order from this input source.

ignoreMetadata - if true, metadata may be ignored during reads.

See Also:

• ImageInputStream

getNumImages

public int getNumImages(boolean allowSearch)
                 throws IOException

Description copied from class: ImageReaderBase

Default implementation that always returns 1.

Overrides:

getNumImages in class ImageReaderBase

Parameters:

allowSearch - ignored, unless overridden

Returns:

1, unless overridden

Throws:

IOException - never, unless overridden

canReadRaster

public boolean canReadRaster()

Overrides:

canReadRaster in class ImageReader

readRaster

public Raster readRaster(int imageIndex,
 ImageReadParam param)
                  throws IOException

Overrides:

readRaster in class ImageReader

Throws:

IOException

readAsRenderedImage

public RenderedImage readAsRenderedImage(int imageIndex,
 ImageReadParam param)
                                  throws IOException

Overrides:

readAsRenderedImage in class ImageReader

Throws:

IOException

abort

public void abort()

Overrides:

abort in class ImageReader

getDefaultReadParam

public ImageReadParam getDefaultReadParam()

Overrides:

getDefaultReadParam in class ImageReader

readerSupportsThumbnails

public boolean readerSupportsThumbnails()

Overrides:

readerSupportsThumbnails in class ImageReader

getNumThumbnails

public int getNumThumbnails(int imageIndex)
                     throws IOException

Overrides:

getNumThumbnails in class ImageReader

Throws:

IOException

getThumbnailWidth

public int getThumbnailWidth(int imageIndex,
 int thumbnailIndex)
                      throws IOException

Overrides:

getThumbnailWidth in class ImageReader

Throws:

IOException

getThumbnailHeight

public int getThumbnailHeight(int imageIndex,
 int thumbnailIndex)
                       throws IOException

Overrides:

getThumbnailHeight in class ImageReader

Throws:

IOException

readThumbnail

public BufferedImage readThumbnail(int imageIndex,
 int thumbnailIndex)
                            throws IOException

Overrides:

readThumbnail in class ImageReader

Throws:

IOException

getImageMetadata

public IIOMetadata getImageMetadata(int imageIndex)
                             throws IOException

Description copied from class: ImageReaderBase

Default implementation that always returns null.

Overrides:

getImageMetadata in class ImageReaderBase

Parameters:

imageIndex - ignored, unless overridden

Returns:

null, unless overridden

Throws:

IOException - never, unless overridden.

getStreamMetadata

public IIOMetadata getStreamMetadata()
                              throws IOException

Description copied from class: ImageReaderBase

Default implementation that always returns null.

Overrides:

getStreamMetadata in class ImageReaderBase

Returns:

null, unless overridden

Throws:

IOException - never, unless overridden.

processWarningOccurred

protected void processWarningOccurred(String warning)

Overrides:

processWarningOccurred in class ImageReader

showIt

protected static void showIt(BufferedImage pImage,
 String pTitle)

main

public static void main(String[] args)
                 throws IOException

Throws:

IOException