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:

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

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private class	JPEGImageReader.JPEGSegmentWarningDelegate
private class	JPEGImageReader.ProgressDelegator

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final int	ALL_APP_MARKERS	Internal constant for referring all APP segments
private int	currentStreamIndex
(package private) static final boolean	DEBUG
private final ImageReader	delegate	Our JPEG reading delegate
(package private) static final boolean	FORCE_RASTER_CONVERSION
private final JPEGImageReader.ProgressDelegator	progressDelegator	Listens to progress updates in the delegate, and delegates back to this instance
private List<Segment>	segments	Cached list of JPEG segments we filter from the underlying stream
private final List<Long>	streamOffsets
private ImageReader	thumbnailReader	Extra delegate for reading JPEG encoded thumbnails
private List<ThumbnailReader>	thumbnails

Fields inherited from class ImageReaderBase

imageInput

Fields inherited from class ImageReader

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

Constructor Summary

Constructors

Constructor	Description
JPEGImageReader(ImageReaderSpi provider, ImageReader delegate)

Method Summary

Modifier and Type	Method	Description
void	abort()
boolean	canReadRaster()
private void	checkThumbnailBounds(int imageIndex, int thumbnailIndex)
private static void	convertYCbCr2RGB(Raster raster, int numComponents)
private static void	convertYCCK2CMYK(Raster raster)
private boolean	delegateCSTypeMismatch(JFIF jfif, AdobeDCT adobeDCT, Frame startOfFrame, JPEGColorSpace sourceCSType)
void	dispose()
private ICC_Profile	ensureDisplayProfile(ICC_Profile profile)
(package private) AdobeDCT	getAdobeDCT()
(package private) List<Application>	getAppSegments(int marker, String identifier)
ImageReadParam	getDefaultReadParam()
(package private) ICC_Profile	getEmbeddedICCProfile(boolean allowBadIndexes)
private EXIF	getExif()
String	getFormatName()
int	getHeight(int imageIndex)
IIOMetadata	getImageMetadata(int imageIndex)	Default implementation that always returns null.
Iterator<ImageTypeSpecifier>	getImageTypes(int imageIndex)
(package private) JFIF	getJFIF()
(package private) JFXX	getJFXX()
int	getNumImages(boolean allowSearch)	Default implementation that always returns 1.
int	getNumThumbnails(int imageIndex)
ImageTypeSpecifier	getRawImageType(int imageIndex)
(package private) Frame	getSOF()
(package private) static JPEGColorSpace	getSourceCSType(JFIF jfif, AdobeDCT adobeDCT, Frame startOfFrame)
IIOMetadata	getStreamMetadata()	Default implementation that always returns null.
int	getThumbnailHeight(int imageIndex, int thumbnailIndex)
(package private) ImageReader	getThumbnailReader()
int	getThumbnailWidth(int imageIndex, int thumbnailIndex)
int	getWidth(int imageIndex)
private void	gotoImage(int imageIndex)
private void	initDelegate(boolean seekForwardOnly, boolean ignoreMetadata)
private void	initHeader()
private void	initHeader(int imageIndex)
private void	installListeners()
(package private) static int	intFromBigEndian(byte[] array, int index)
(package private) static void	intToBigEndian(int value, byte[] array, int index)
private static void	invertCMYK(Raster raster)
private boolean	isLossless()
private Application	lastAppSegment(int marker, String identifier)
static void	main(String[] args)
private CompoundDirectory	parseExif(EXIF exif)
protected void	processWarningOccurred(String warning)
BufferedImage	read(int imageIndex, ImageReadParam param)
RenderedImage	readAsRenderedImage(int imageIndex, ImageReadParam param)
boolean	readerSupportsThumbnails()
private ICC_Profile	readICCProfileSafe(InputStream stream, boolean allowBadProfile)
private BufferedImage	readImageAsRasterAndReplaceColorProfile(int imageIndex, ImageReadParam param, Frame startOfFrame, JPEGColorSpace csType, ICC_Profile profile)
Raster	readRaster(int imageIndex, ImageReadParam param)
private List<JPEGSegment>	readSegments()
BufferedImage	readThumbnail(int imageIndex, int thumbnailIndex)
private void	readThumbnailMetadata(int imageIndex)
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

Field Details

DEBUG

static final boolean DEBUG

FORCE_RASTER_CONVERSION

static final boolean FORCE_RASTER_CONVERSION

ALL_APP_MARKERS

static final int ALL_APP_MARKERS

Internal constant for referring all APP segments

See Also:

• Constant Field Values

delegate

private final ImageReader delegate

Our JPEG reading delegate

progressDelegator

private final JPEGImageReader.ProgressDelegator progressDelegator

Listens to progress updates in the delegate, and delegates back to this instance

thumbnailReader

private ImageReader thumbnailReader

Extra delegate for reading JPEG encoded thumbnails

thumbnails

private List<ThumbnailReader> thumbnails

segments

private List<Segment> segments

Cached list of JPEG segments we filter from the underlying stream

currentStreamIndex

private int currentStreamIndex

streamOffsets

private final List<Long> streamOffsets

Constructor Details

JPEGImageReader

JPEGImageReader(ImageReaderSpi provider,
 ImageReader delegate)

Method Details

installListeners

private void installListeners()

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

isLossless

private boolean isLossless()
                    throws IOException

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

delegateCSTypeMismatch

private boolean delegateCSTypeMismatch(JFIF jfif,
 AdobeDCT adobeDCT,
 Frame startOfFrame,
 JPEGColorSpace sourceCSType)
                                throws IOException

Throws:

IOException

readImageAsRasterAndReplaceColorProfile

private BufferedImage readImageAsRasterAndReplaceColorProfile(int imageIndex,
 ImageReadParam param,
 Frame startOfFrame,
 JPEGColorSpace csType,
 ICC_Profile profile)
                                                       throws IOException

Throws:

IOException

getSourceCSType

static JPEGColorSpace getSourceCSType(JFIF jfif,
 AdobeDCT adobeDCT,
 Frame startOfFrame)
                               throws IIOException

Throws:

IIOException

ensureDisplayProfile

private ICC_Profile ensureDisplayProfile(ICC_Profile profile)
                                  throws IOException

Throws:

IOException

intFromBigEndian

static int intFromBigEndian(byte[] array,
 int index)

intToBigEndian

static void intToBigEndian(int value,
 byte[] array,
 int index)

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

initDelegate

private void initDelegate(boolean seekForwardOnly,
 boolean ignoreMetadata)
                   throws IOException

Throws:

IOException

initHeader

private void initHeader()
                 throws IOException

Throws:

IOException

initHeader

private void initHeader(int imageIndex)
                 throws IOException

Throws:

IOException

gotoImage

private void gotoImage(int imageIndex)
                throws IOException

Throws:

IOException

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

readSegments

private List<JPEGSegment> readSegments()
                                throws IOException

Throws:

IOException

getAppSegments

List<Application> getAppSegments(int marker,
 String identifier)
                          throws IOException

Throws:

IOException

getSOF

Frame getSOF()
      throws IOException

Throws:

IOException

lastAppSegment

private Application lastAppSegment(int marker,
 String identifier)
                            throws IOException

Throws:

IOException

getAdobeDCT

AdobeDCT getAdobeDCT()
              throws IOException

Throws:

IOException

getJFIF

JFIF getJFIF()
      throws IOException

Throws:

IOException

getJFXX

JFXX getJFXX()
      throws IOException

Throws:

IOException

getExif

private EXIF getExif()
              throws IOException

Throws:

IOException

parseExif

private CompoundDirectory parseExif(EXIF exif)
                             throws IOException

Throws:

IOException

getEmbeddedICCProfile

ICC_Profile getEmbeddedICCProfile(boolean allowBadIndexes)
                           throws IOException

Throws:

IOException

readICCProfileSafe

private ICC_Profile readICCProfileSafe(InputStream stream,
 boolean allowBadProfile)

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

readThumbnailMetadata

private void readThumbnailMetadata(int imageIndex)
                            throws IOException

Throws:

IOException

getThumbnailReader

ImageReader getThumbnailReader()
                        throws IOException

Throws:

IOException

getNumThumbnails

public int getNumThumbnails(int imageIndex)
                     throws IOException

Overrides:

getNumThumbnails in class ImageReader

Throws:

IOException

checkThumbnailBounds

private void checkThumbnailBounds(int imageIndex,
 int thumbnailIndex)
                           throws IOException

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

invertCMYK

private static void invertCMYK(Raster raster)

convertYCbCr2RGB

private static void convertYCbCr2RGB(Raster raster,
 int numComponents)

convertYCCK2CMYK

private static void convertYCCK2CMYK(Raster raster)

showIt

protected static void showIt(BufferedImage pImage,
 String pTitle)

main

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

Throws:

IOException