public abstract class ImageReader extends Object
 ImageReader objects are normally instantiated by
 the service provider interface (SPI) class for the specific format.
 Service provider classes (e.g., instances of
 ImageReaderSpi) are registered with the
 IIORegistry, which uses them for format recognition
 and presentation of available format readers and writers.
 
 When an input source is set (using the setInput
 method), it may be marked as "seek forward only".  This setting
 means that images contained within the input source will only be
 read in order, possibly allowing the reader to avoid caching
 portions of the input containing data associated with images that
 have been read previously.
ImageWriter, 
IIORegistry, 
ImageReaderSpi| Modifier and Type | Field and Description | 
|---|---|
| protected Locale[] | availableLocalesAn array of  Locales which may be used to localize
 warning messages, ornullif localization is not
 supported. | 
| protected boolean | ignoreMetadatatrueif the current input source has been marked
 as allowing metadata to be ignored bysetInput. | 
| protected Object | inputThe  ImageInputStreamor otherObjectbysetInputand retrieved
 bygetInput. | 
| protected Locale | localeThe current  Localeto be used for localization, ornullif none has been set. | 
| protected int | minIndexThe smallest valid index for reading, initially 0. | 
| protected ImageReaderSpi | originatingProviderThe  ImageReaderSpithat instantiated this object,
 ornullif its identity is not known or none
 exists. | 
| protected List<IIOReadProgressListener> | progressListenersA  Listof currently registeredIIOReadProgressListeners, initialized by default
 tonull, which is synonymous with an emptyList. | 
| protected boolean | seekForwardOnlytrueif the current input source has been marked
 as allowing only forward seeking bysetInput. | 
| protected List<IIOReadUpdateListener> | updateListenersA  Listof currently registeredIIOReadUpdateListeners, initialized by default tonull, which is synonymous with an emptyList. | 
| protected List<IIOReadWarningListener> | warningListenersA  Listof currently registeredIIOReadWarningListeners, initialized by default tonull, which is synonymous with an emptyList. | 
| protected List<Locale> | warningLocalesA  Listof theLocales associated with
 each currently registeredIIOReadWarningListener,
 initialized by default tonull, which is
 synonymous with an emptyList. | 
| Modifier | Constructor and Description | 
|---|---|
| protected  | ImageReader(ImageReaderSpi originatingProvider)Constructs an  ImageReaderand sets itsoriginatingProviderfield to the supplied value. | 
| Modifier and Type | Method and Description | 
|---|---|
| void | abort()Requests that any current read operation be aborted. | 
| protected boolean | abortRequested()Returns  trueif a request to abort the current
 read operation has been made since the reader was instantiated orclearAbortRequestwas called. | 
| void | addIIOReadProgressListener(IIOReadProgressListener listener)Adds an  IIOReadProgressListenerto the list of
 registered progress listeners. | 
| void | addIIOReadUpdateListener(IIOReadUpdateListener listener)Adds an  IIOReadUpdateListenerto the list of
 registered update listeners. | 
| void | addIIOReadWarningListener(IIOReadWarningListener listener)Adds an  IIOReadWarningListenerto the list of
 registered warning listeners. | 
| boolean | canReadRaster()Returns  trueif this plug-in supports reading
 just aRasterof pixel data. | 
| protected static void | checkReadParamBandSettings(ImageReadParam param,
                          int numSrcBands,
                          int numDstBands)A utility method that may be used by readers to test the
 validity of the source and destination band settings of an
  ImageReadParam. | 
| protected void | clearAbortRequest()Clears any previous abort request. | 
| protected static void | computeRegions(ImageReadParam param,
              int srcWidth,
              int srcHeight,
              BufferedImage image,
              Rectangle srcRegion,
              Rectangle destRegion)Computes the source region of interest and the destination
 region of interest, taking the width and height of the source
 image, an optional destination image, and an optional
  ImageReadParaminto account. | 
| void | dispose()Allows any resources held by this object to be released. | 
| float | getAspectRatio(int imageIndex)Returns the aspect ratio of the given image (that is, its width
 divided by its height) as a  float. | 
| Locale[] | getAvailableLocales()Returns an array of  Locales that may be used to
 localize warning listeners and compression settings. | 
| ImageReadParam | getDefaultReadParam()Returns a default  ImageReadParamobject
 appropriate for this format. | 
| protected static BufferedImage | getDestination(ImageReadParam param,
              Iterator<ImageTypeSpecifier> imageTypes,
              int width,
              int height)Returns the  BufferedImageto which decoded pixel
 data should be written. | 
| String | getFormatName()Returns a  Stringidentifying the format of the
 input source. | 
| abstract int | getHeight(int imageIndex)Returns the height in pixels of the given image within the
 input source. | 
| abstract IIOMetadata | getImageMetadata(int imageIndex)Returns an  IIOMetadataobject containing metadata
 associated with the given image, ornullif the
 reader does not support reading metadata, is set to ignore
 metadata, or if no metadata is available. | 
| IIOMetadata | getImageMetadata(int imageIndex,
                String formatName,
                Set<String> nodeNames)Returns an  IIOMetadataobject representing the
 metadata associated with the given image, ornullif the reader does not support reading metadata or none
 is available. | 
| abstract Iterator<ImageTypeSpecifier> | getImageTypes(int imageIndex)Returns an  Iteratorcontaining possible image
 types to which the given image may be decoded, in the form ofImageTypeSpecifierss. | 
| Object | getInput()Returns the  ImageInputStreamor otherObjectpreviously set as the input source. | 
| Locale | getLocale()Returns the currently set  Locale, ornullif none has been set. | 
| int | getMinIndex()Returns the lowest valid index for reading an image, thumbnail,
 or image metadata. | 
| abstract int | getNumImages(boolean allowSearch)Returns the number of images, not including thumbnails, available
 from the current input source. | 
| int | getNumThumbnails(int imageIndex)Returns the number of thumbnail preview images associated with
 the given image. | 
| ImageReaderSpi | getOriginatingProvider()Returns the  ImageReaderSpithat was passed in on
 the constructor. | 
| ImageTypeSpecifier | getRawImageType(int imageIndex)Returns an  ImageTypeSpecifierindicating theSampleModelandColorModelwhich most
 closely represents the "raw" internal format of the image. | 
| protected static Rectangle | getSourceRegion(ImageReadParam param,
               int srcWidth,
               int srcHeight)A utility method that may be used by readers to compute the
 region of the source image that should be read, taking into
 account any source region and subsampling offset settings in
 the supplied  ImageReadParam. | 
| abstract IIOMetadata | getStreamMetadata()Returns an  IIOMetadataobject representing the
 metadata associated with the input source as a whole (i.e., not
 associated with any particular image), ornullif
 the reader does not support reading metadata, is set to ignore
 metadata, or if no metadata is available. | 
| IIOMetadata | getStreamMetadata(String formatName,
                 Set<String> nodeNames)Returns an  IIOMetadataobject representing the
 metadata associated with the input source as a whole (i.e.,
 not associated with any particular image). | 
| int | getThumbnailHeight(int imageIndex,
                  int thumbnailIndex)Returns the height of the thumbnail preview image indexed by
  thumbnailIndex, associated with the image indexed
 byImageIndex. | 
| int | getThumbnailWidth(int imageIndex,
                 int thumbnailIndex)Returns the width of the thumbnail preview image indexed by
  thumbnailIndex, associated with the image indexed
 byImageIndex. | 
| int | getTileGridXOffset(int imageIndex)Returns the X coordinate of the upper-left corner of tile (0,
 0) in the given image. | 
| int | getTileGridYOffset(int imageIndex)Returns the Y coordinate of the upper-left corner of tile (0,
 0) in the given image. | 
| int | getTileHeight(int imageIndex)Returns the height of a tile in the given image. | 
| int | getTileWidth(int imageIndex)Returns the width of a tile in the given image. | 
| abstract int | getWidth(int imageIndex)Returns the width in pixels of the given image within the input
 source. | 
| boolean | hasThumbnails(int imageIndex)Returns  trueif the given image has thumbnail
 preview images associated with it. | 
| boolean | isIgnoringMetadata()Returns  trueif the current input source has been
 marked as allowing metadata to be ignored by passingtrueas theignoreMetadataargument
 to thesetInputmethod. | 
| boolean | isImageTiled(int imageIndex)Returns  trueif the image is organized into
 tiles, that is, equal-sized non-overlapping rectangles. | 
| boolean | isRandomAccessEasy(int imageIndex)Returns  trueif the storage format of the given
 image places no inherent impediment on random access to pixels. | 
| boolean | isSeekForwardOnly()Returns  trueif the current input source has been
 marked as seek forward only by passingtrueas theseekForwardOnlyargument to thesetInputmethod. | 
| protected void | processImageComplete()Broadcasts the completion of an image read to all registered
  IIOReadProgressListeners by calling theirimageCompletemethod. | 
| protected void | processImageProgress(float percentageDone)Broadcasts the current percentage of image completion to all
 registered  IIOReadProgressListeners by calling
 theirimageProgressmethod. | 
| protected void | processImageStarted(int imageIndex)Broadcasts the start of an image read to all registered
  IIOReadProgressListeners by calling theirimageStartedmethod. | 
| protected void | processImageUpdate(BufferedImage theImage,
                  int minX,
                  int minY,
                  int width,
                  int height,
                  int periodX,
                  int periodY,
                  int[] bands)Broadcasts the update of a set of samples to all registered
  IIOReadUpdateListeners by calling theirimageUpdatemethod. | 
| protected void | processPassComplete(BufferedImage theImage)Broadcasts the end of a progressive pass to all
 registered  IIOReadUpdateListeners by calling theirpassCompletemethod. | 
| protected void | processPassStarted(BufferedImage theImage,
                  int pass,
                  int minPass,
                  int maxPass,
                  int minX,
                  int minY,
                  int periodX,
                  int periodY,
                  int[] bands)Broadcasts the beginning of a progressive pass to all
 registered  IIOReadUpdateListeners by calling theirpassStartedmethod. | 
| protected void | processReadAborted()Broadcasts that the read has been aborted to all registered
  IIOReadProgressListeners by calling theirreadAbortedmethod. | 
| protected void | processSequenceComplete()Broadcasts the completion of an sequence of image reads to all
 registered  IIOReadProgressListeners by calling
 theirsequenceCompletemethod. | 
| protected void | processSequenceStarted(int minIndex)Broadcasts the start of an sequence of image reads to all
 registered  IIOReadProgressListeners by calling
 theirsequenceStartedmethod. | 
| protected void | processThumbnailComplete()Broadcasts the completion of a thumbnail read to all registered
  IIOReadProgressListeners by calling theirthumbnailCompletemethod. | 
| protected void | processThumbnailPassComplete(BufferedImage theThumbnail)Broadcasts the end of a thumbnail progressive pass to all
 registered  IIOReadUpdateListeners by calling theirthumbnailPassCompletemethod. | 
| protected void | processThumbnailPassStarted(BufferedImage theThumbnail,
                           int pass,
                           int minPass,
                           int maxPass,
                           int minX,
                           int minY,
                           int periodX,
                           int periodY,
                           int[] bands)Broadcasts the beginning of a thumbnail progressive pass to all
 registered  IIOReadUpdateListeners by calling theirthumbnailPassStartedmethod. | 
| protected void | processThumbnailProgress(float percentageDone)Broadcasts the current percentage of thumbnail completion to
 all registered  IIOReadProgressListeners by calling
 theirthumbnailProgressmethod. | 
| protected void | processThumbnailStarted(int imageIndex,
                       int thumbnailIndex)Broadcasts the start of a thumbnail read to all registered
  IIOReadProgressListeners by calling theirthumbnailStartedmethod. | 
| protected void | processThumbnailUpdate(BufferedImage theThumbnail,
                      int minX,
                      int minY,
                      int width,
                      int height,
                      int periodX,
                      int periodY,
                      int[] bands)Broadcasts the update of a set of samples in a thumbnail image
 to all registered  IIOReadUpdateListeners by
 calling theirthumbnailUpdatemethod. | 
| protected void | processWarningOccurred(String warning)Broadcasts a warning message to all registered
  IIOReadWarningListeners by calling theirwarningOccurredmethod. | 
| protected void | processWarningOccurred(String baseName,
                      String keyword)Broadcasts a localized warning message to all registered
  IIOReadWarningListeners by calling theirwarningOccurredmethod with a string taken
 from aResourceBundle. | 
| BufferedImage | read(int imageIndex)Reads the image indexed by  imageIndexand returns
 it as a completeBufferedImage, using a defaultImageReadParam. | 
| abstract BufferedImage | read(int imageIndex,
    ImageReadParam param)Reads the image indexed by  imageIndexand returns
 it as a completeBufferedImage, using a suppliedImageReadParam. | 
| IIOImage | readAll(int imageIndex,
       ImageReadParam param)Reads the image indexed by  imageIndexand returns
 anIIOImagecontaining the image, thumbnails, and
 associated image metadata, using a suppliedImageReadParam. | 
| Iterator<IIOImage> | readAll(Iterator<? extends ImageReadParam> params)Returns an  Iteratorcontaining all the images,
 thumbnails, and metadata, starting at the index given bygetMinIndex, from the input source in the form ofIIOImageobjects. | 
| RenderedImage | readAsRenderedImage(int imageIndex,
                   ImageReadParam param)Returns a  RenderedImageobject that contains the
 contents of the image indexed byimageIndex. | 
| boolean | readerSupportsThumbnails()Returns  trueif the image format understood by
 this reader supports thumbnail preview images associated with
 it. | 
| Raster | readRaster(int imageIndex,
          ImageReadParam param)Returns a new  Rasterobject containing the raw pixel data
 from the image stream, without any color conversion applied. | 
| BufferedImage | readThumbnail(int imageIndex,
             int thumbnailIndex)Returns the thumbnail preview image indexed by
  thumbnailIndex, associated with the image indexed
 byImageIndexas aBufferedImage. | 
| BufferedImage | readTile(int imageIndex,
        int tileX,
        int tileY)Reads the tile indicated by the  tileXandtileYarguments, returning it as aBufferedImage. | 
| Raster | readTileRaster(int imageIndex,
              int tileX,
              int tileY)Returns a new  Rasterobject containing the raw
 pixel data from the tile, without any color conversion applied. | 
| void | removeAllIIOReadProgressListeners()Removes all currently registered
  IIOReadProgressListenerobjects. | 
| void | removeAllIIOReadUpdateListeners()Removes all currently registered
  IIOReadUpdateListenerobjects. | 
| void | removeAllIIOReadWarningListeners()Removes all currently registered
  IIOReadWarningListenerobjects. | 
| void | removeIIOReadProgressListener(IIOReadProgressListener listener)Removes an  IIOReadProgressListenerfrom the list
 of registered progress listeners. | 
| void | removeIIOReadUpdateListener(IIOReadUpdateListener listener)Removes an  IIOReadUpdateListenerfrom the list of
 registered update listeners. | 
| void | removeIIOReadWarningListener(IIOReadWarningListener listener)Removes an  IIOReadWarningListenerfrom the list of
 registered error listeners. | 
| void | reset()Restores the  ImageReaderto its initial state. | 
| void | setInput(Object input)Sets the input source to use to the given
  ImageInputStreamor otherObject. | 
| void | setInput(Object input,
        boolean seekForwardOnly)Sets the input source to use to the given
  ImageInputStreamor otherObject. | 
| void | setInput(Object input,
        boolean seekForwardOnly,
        boolean ignoreMetadata)Sets the input source to use to the given
  ImageInputStreamor otherObject. | 
| void | setLocale(Locale locale)Sets the current  Localeof thisImageReaderto the given value. | 
protected ImageReaderSpi originatingProvider
ImageReaderSpi that instantiated this object,
 or null if its identity is not known or none
 exists.  By default it is initialized to null.protected Object input
ImageInputStream or other
 Object by setInput and retrieved
 by getInput.  By default it is initialized to
 null.protected boolean seekForwardOnly
true if the current input source has been marked
 as allowing only forward seeking by setInput.  By
 default, the value is false.protected boolean ignoreMetadata
true if the current input source has been marked
 as allowing metadata to be ignored by setInput.
 By default, the value is false.protected int minIndex
seekForwardOnly is true, various methods
 may throw an IndexOutOfBoundsException on an
 attempt to access data associate with an image having a lower
 index.protected Locale[] availableLocales
Locales which may be used to localize
 warning messages, or null if localization is not
 supported.protected Locale locale
Locale to be used for localization, or
 null if none has been set.protected List<IIOReadWarningListener> warningListeners
List of currently registered
 IIOReadWarningListeners, initialized by default to
 null, which is synonymous with an empty
 List.protected List<Locale> warningLocales
List of the Locales associated with
 each currently registered IIOReadWarningListener,
 initialized by default to null, which is
 synonymous with an empty List.protected List<IIOReadProgressListener> progressListeners
List of currently registered
 IIOReadProgressListeners, initialized by default
 to null, which is synonymous with an empty
 List.protected List<IIOReadUpdateListener> updateListeners
List of currently registered
 IIOReadUpdateListeners, initialized by default to
 null, which is synonymous with an empty
 List.protected ImageReader(ImageReaderSpi originatingProvider)
ImageReader and sets its
 originatingProvider field to the supplied value.
  Subclasses that make use of extensions should provide a
 constructor with signature (ImageReaderSpi,
 Object) in order to retrieve the extension object.  If
 the extension object is unsuitable, an
 IllegalArgumentException should be thrown.
originatingProvider - the ImageReaderSpi that is
 invoking this constructor, or null.public String getFormatName() throws IOException
String identifying the format of the
 input source.
  The default implementation returns
 originatingProvider.getFormatNames()[0].
 Implementations that may not have an originating service
 provider, or which desire a different naming policy should
 override this method.
IOException - if an error occurs reading the
 information from the input source.String.public ImageReaderSpi getOriginatingProvider()
ImageReaderSpi that was passed in on
 the constructor.  Note that this value may be null.ImageReaderSpi, or null.ImageReaderSpipublic void setInput(Object input, boolean seekForwardOnly, boolean ignoreMetadata)
ImageInputStream or other Object.
 The input source must be set before any of the query or read
 methods are used.  If input is null,
 any currently set input source will be removed.  In any case,
 the value of minIndex will be initialized to 0.
  The seekForwardOnly parameter controls whether
 the value returned by getMinIndex will be
 increased as each image (or thumbnail, or image metadata) is
 read.  If seekForwardOnly is true, then a call to
 read(index) will throw an
 IndexOutOfBoundsException if index < this.minIndex;
 otherwise, the value of
 minIndex will be set to index.  If
 seekForwardOnly is false, the value of
 minIndex will remain 0 regardless of any read
 operations.
 
 The ignoreMetadata parameter, if set to
 true, allows the reader to disregard any metadata
 encountered during the read.  Subsequent calls to the
 getStreamMetadata and
 getImageMetadata methods may return
 null, and an IIOImage returned from
 readAll may return null from their
 getMetadata method.  Setting this parameter may
 allow the reader to work more efficiently.  The reader may
 choose to disregard this setting and return metadata normally.
 
Subclasses should take care to remove any cached information based on the previous stream, such as header information or partially decoded image data.
 Use of a general Object other than an
 ImageInputStream is intended for readers that
 interact directly with a capture device or imaging protocol.
 The set of legal classes is advertised by the reader's service
 provider's getInputTypes method; most readers
 will return a single-element array containing only
 ImageInputStream.class to indicate that they
 accept only an ImageInputStream.
 
 The default implementation checks the input
 argument against the list returned by
 originatingProvider.getInputTypes() and fails
 if the argument is not an instance of one of the classes
 in the list.  If the originating provider is set to
 null, the input is accepted only if it is an
 ImageInputStream.
IllegalArgumentException - if input is
 not an instance of one of the classes returned by the
 originating service provider's getInputTypes
 method, or is not an ImageInputStream.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.ImageInputStream, 
getInput(), 
ImageReaderSpi.getInputTypes()public void setInput(Object input, boolean seekForwardOnly)
ImageInputStream or other Object.
 The input source must be set before any of the query or read
 methods are used.  If input is null,
 any currently set input source will be removed.  In any case,
 the value of minIndex will be initialized to 0.
  The seekForwardOnly parameter controls whether
 the value returned by getMinIndex will be
 increased as each image (or thumbnail, or image metadata) is
 read.  If seekForwardOnly is true, then a call to
 read(index) will throw an
 IndexOutOfBoundsException if index < this.minIndex;
 otherwise, the value of
 minIndex will be set to index.  If
 seekForwardOnly is false, the value of
 minIndex will remain 0 regardless of any read
 operations.
 
 This method is equivalent to setInput(input,
 seekForwardOnly, false).
IllegalArgumentException - if input is
 not an instance of one of the classes returned by the
 originating service provider's getInputTypes
 method, or is not an ImageInputStream.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.getInput()public void setInput(Object input)
ImageInputStream or other Object.
 The input source must be set before any of the query or read
 methods are used.  If input is null,
 any currently set input source will be removed.  In any case,
 the value of minIndex will be initialized to 0.
  This method is equivalent to setInput(input, false,
 false).
IllegalArgumentException - if input is
 not an instance of one of the classes returned by the
 originating service provider's getInputTypes
 method, or is not an ImageInputStream.input - the ImageInputStream or other
 Object to use for future decoding.getInput()public Object getInput()
ImageInputStream or other
 Object previously set as the input source.  If the
 input source has not been set, null is returned.Object that will be used for future
 decoding, or null.ImageInputStream, 
setInput(java.lang.Object, boolean, boolean)public boolean isSeekForwardOnly()
true if the current input source has been
 marked as seek forward only by passing true as the
 seekForwardOnly argument to the
 setInput method.true if the input source is seek forward
 only.setInput(java.lang.Object, boolean, boolean)public boolean isIgnoringMetadata()
true if the current input source has been
 marked as allowing metadata to be ignored by passing
 true as the ignoreMetadata argument
 to the setInput method.true if the metadata may be ignored.setInput(java.lang.Object, boolean, boolean)public int getMinIndex()
seekForwardOnly() is
 false, this value will typically remain 0,
 indicating that random access is possible.  Otherwise, it will
 contain the value of the most recently accessed index, and
 increase in a monotonic fashion.public Locale[] getAvailableLocales()
Locales that may be used to
 localize warning listeners and compression settings.  A return
 value of null indicates that localization is not
 supported.
  The default implementation returns a clone of the
 availableLocales instance variable if it is
 non-null, or else returns null.
Locales that may be used as
 arguments to setLocale, or null.public void setLocale(Locale locale)
Locale of this
 ImageReader to the given value.  A value of
 null removes any previous setting, and indicates
 that the reader should localize as it sees fit.IllegalArgumentException - if locale is
 non-null but is not one of the values returned by
 getAvailableLocales.locale - the desired Locale, or
 null.getLocale()public Locale getLocale()
Locale, or
 null if none has been set.Locale, or null.setLocale(java.util.Locale)public abstract int getNumImages(boolean allowSearch)
                          throws IOException
 Note that some image formats (such as animated GIF) do not
 specify how many images are present in the stream.  Thus
 determining the number of images will require the entire stream
 to be scanned and may require memory for buffering.  If images
 are to be processed in order, it may be more efficient to
 simply call read with increasing indices until an
 IndexOutOfBoundsException is thrown to indicate
 that no more images are available.  The
 allowSearch parameter may be set to
 false to indicate that an exhaustive search is not
 desired; the return value will be -1 to indicate
 that a search is necessary.  If the input has been specified
 with seekForwardOnly set to true,
 this method throws an IllegalStateException if
 allowSearch is set to true.
IllegalStateException - if the input source has not been set,
 or if the input has been specified with seekForwardOnly
 set to true.IOException - if an error occurs reading the
 information from the input source.allowSearch - if true, the true number of
 images will be returned even if a search is required.  If
 false, the reader may return -1
 without performing the search.int, or
 -1 if allowSearch is
 false and a search would be required.setInput(java.lang.Object, boolean, boolean)public abstract int getWidth(int imageIndex)
                      throws IOException
If the image can be rendered to a user-specified size, then this method returns the default width.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs reading the width
 information from the input source.imageIndex - the index of the image to be queried.int.public abstract int getHeight(int imageIndex)
                       throws IOException
If the image can be rendered to a user-specified size, then this method returns the default height.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs reading the height
 information from the input source.imageIndex - the index of the image to be queried.int.public boolean isRandomAccessEasy(int imageIndex)
                           throws IOException
true if the storage format of the given
 image places no inherent impediment on random access to pixels.
 For most compressed formats, such as JPEG, this method should
 return false, as a large section of the image in
 addition to the region of interest may need to be decoded.
  This is merely a hint for programs that wish to be
 efficient; all readers must be able to read arbitrary regions
 as specified in an ImageReadParam.
 
 Note that formats that return false from
 this method may nonetheless allow tiling (e.g. Restart
 Markers in JPEG), and random access will likely be reasonably
 efficient on tiles.  See isImageTiled.
 
 A reader for which all images are guaranteed to support
 easy random access, or are guaranteed not to support easy
 random access, may return true or
 false respectively without accessing any image
 data.  In such cases, it is not necessary to throw an exception
 even if no input source has been set or the image index is out
 of bounds.
 
 The default implementation returns false.
IllegalStateException - if an input source is required
 to determine the return value, but none has been set.IndexOutOfBoundsException - if an image must be
 accessed to determine the return value, but the supplied index
 is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.true if reading a region of interest of
 the given image is likely to be efficient.public float getAspectRatio(int imageIndex)
                     throws IOException
float.  For images
 that are inherently resizable, this method provides a way to
 determine the appropriate width given a desired height, or vice
 versa.  For non-resizable images, the true width and height
 are used.
  The default implementation simply returns
 (float)getWidth(imageIndex)/getHeight(imageIndex).
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.float indicating the aspect ratio of the
 given image.public ImageTypeSpecifier getRawImageType(int imageIndex) throws IOException
ImageTypeSpecifier indicating the
 SampleModel and ColorModel which most
 closely represents the "raw" internal format of the image.  For
 example, for a JPEG image the raw type might have a YCbCr color
 space even though the image would conventionally be transformed
 into an RGB color space prior to display.  The returned value
 should also be included in the list of values returned by
 getImageTypes.
  The default implementation simply returns the first entry
 from the list provided by getImageType.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs reading the format
 information from the input source.imageIndex - the index of the image to be queried.ImageTypeSpecifier.public abstract Iterator<ImageTypeSpecifier> getImageTypes(int imageIndex) throws IOException
Iterator containing possible image
 types to which the given image may be decoded, in the form of
 ImageTypeSpecifierss.  At least one legal image
 type will be returned.
 The first element of the iterator should be the most "natural" type for decoding the image with as little loss as possible. For example, for a JPEG image the first entry should be an RGB image, even though the image data is stored internally in a YCbCr color space.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs reading the format
 information from the input source.imageIndex - the index of the image to be
 retrieved.Iterator containing at least one
 ImageTypeSpecifier representing suggested image
 types for decoding the current given image.ImageReadParam.setDestination(BufferedImage), 
ImageReadParam.setDestinationType(ImageTypeSpecifier)public ImageReadParam getDefaultReadParam()
ImageReadParam object
 appropriate for this format.  All subclasses should define a
 set of default values for all parameters and return them with
 this call.  This method may be called before the input source
 is set.
  The default implementation constructs and returns a new
 ImageReadParam object that does not allow source
 scaling (i.e., it returns new
 ImageReadParam().
ImageReadParam object which may be used
 to control the decoding process using a set of default settings.public abstract IIOMetadata getStreamMetadata() throws IOException
IIOMetadata object representing the
 metadata associated with the input source as a whole (i.e., not
 associated with any particular image), or null if
 the reader does not support reading metadata, is set to ignore
 metadata, or if no metadata is available.IOException - if an error occurs during reading.IIOMetadata object, or null.public IIOMetadata getStreamMetadata(String formatName, Set<String> nodeNames) throws IOException
IIOMetadata object representing the
 metadata associated with the input source as a whole (i.e.,
 not associated with any particular image).  If no such data
 exists, null is returned.
  The resulting metadata object is only responsible for
 returning documents in the format named by
 formatName.  Within any documents that are
 returned, only nodes whose names are members of
 nodeNames are required to be returned.  In this
 way, the amount of metadata processing done by the reader may
 be kept to a minimum, based on what information is actually
 needed.
 
 If formatName is not the name of a supported
 metadata format, null is returned.
 
In all cases, it is legal to return a more capable metadata object than strictly necessary. The format name and node names are merely hints that may be used to reduce the reader's workload.
 The default implementation simply returns the result of
 calling getStreamMetadata(), after checking that
 the format name is supported.  If it is not,
 null is returned.
IllegalArgumentException - if formatName
 is null.IllegalArgumentException - if nodeNames
 is null.IOException - if an error occurs during reading.formatName - a metadata format name that may be used to retrieve
 a document from the returned IIOMetadata object.nodeNames - a Set containing the names of
 nodes that may be contained in a retrieved document.IIOMetadata object, or null.public abstract IIOMetadata getImageMetadata(int imageIndex) throws IOException
IIOMetadata object containing metadata
 associated with the given image, or null if the
 reader does not support reading metadata, is set to ignore
 metadata, or if no metadata is available.IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image whose metadata is to
 be retrieved.IIOMetadata object, or
 null.public IIOMetadata getImageMetadata(int imageIndex, String formatName, Set<String> nodeNames) throws IOException
IIOMetadata object representing the
 metadata associated with the given image, or null
 if the reader does not support reading metadata or none
 is available.
  The resulting metadata object is only responsible for
 returning documents in the format named by
 formatName.  Within any documents that are
 returned, only nodes whose names are members of
 nodeNames are required to be returned.  In this
 way, the amount of metadata processing done by the reader may
 be kept to a minimum, based on what information is actually
 needed.
 
 If formatName is not the name of a supported
 metadata format, null may be returned.
 
In all cases, it is legal to return a more capable metadata object than strictly necessary. The format name and node names are merely hints that may be used to reduce the reader's workload.
 The default implementation simply returns the result of
 calling getImageMetadata(imageIndex), after
 checking that the format name is supported.  If it is not,
 null is returned.
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IllegalArgumentException - if formatName
 is null.IllegalArgumentException - if nodeNames
 is null.IOException - if an error occurs during reading.imageIndex - the index of the image whose metadata is to
 be retrieved.formatName - a metadata format name that may be used to retrieve
 a document from the returned IIOMetadata object.nodeNames - a Set containing the names of
 nodes that may be contained in a retrieved document.IIOMetadata object, or null.public BufferedImage read(int imageIndex) throws IOException
imageIndex and returns
 it as a complete BufferedImage, using a default
 ImageReadParam.  This is a convenience method
 that calls read(imageIndex, null).
  The image returned will be formatted according to the first
 ImageTypeSpecifier returned from
 getImageTypes.
 
 Any registered IIOReadProgressListener objects
 will be notified by calling their imageStarted
 method, followed by calls to their imageProgress
 method as the read progresses.  Finally their
 imageComplete method will be called.
 IIOReadUpdateListener objects may be updated at
 other times during the read as pixels are decoded.  Finally,
 IIOReadWarningListener objects will receive
 notification of any non-fatal warnings that occur during
 decoding.
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.BufferedImage.public abstract BufferedImage read(int imageIndex, ImageReadParam param) throws IOException
imageIndex and returns
 it as a complete BufferedImage, using a supplied
 ImageReadParam.
  The actual BufferedImage returned will be
 chosen using the algorithm defined by the
 getDestination method.
 
 Any registered IIOReadProgressListener objects
 will be notified by calling their imageStarted
 method, followed by calls to their imageProgress
 method as the read progresses.  Finally their
 imageComplete method will be called.
 IIOReadUpdateListener objects may be updated at
 other times during the read as pixels are decoded.  Finally,
 IIOReadWarningListener objects will receive
 notification of any non-fatal warnings that occur during
 decoding.
 
 The set of source bands to be read and destination bands to
 be written is determined by calling getSourceBands
 and getDestinationBands on the supplied
 ImageReadParam.  If the lengths of the arrays
 returned by these methods differ, the set of source bands
 contains an index larger that the largest available source
 index, or the set of destination bands contains an index larger
 than the largest legal destination index, an
 IllegalArgumentException is thrown.
 
 If the supplied ImageReadParam contains
 optional setting values not supported by this reader (e.g.
 source render size or any format-specific settings), they will
 be ignored.
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IllegalArgumentException - if the set of source and
 destination bands specified by
 param.getSourceBands and
 param.getDestinationBands differ in length or
 include indices that are out of bounds.IllegalArgumentException - if the resulting image would
 have a width or height less than 1.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.param - an ImageReadParam used to control
 the reading process, or null.BufferedImage.public IIOImage readAll(int imageIndex, ImageReadParam param) throws IOException
imageIndex and returns
 an IIOImage containing the image, thumbnails, and
 associated image metadata, using a supplied
 ImageReadParam.
  The actual BufferedImage referenced by the
 returned IIOImage will be chosen using the
 algorithm defined by the getDestination method.
 
 Any registered IIOReadProgressListener objects
 will be notified by calling their imageStarted
 method, followed by calls to their imageProgress
 method as the read progresses.  Finally their
 imageComplete method will be called.
 IIOReadUpdateListener objects may be updated at
 other times during the read as pixels are decoded.  Finally,
 IIOReadWarningListener objects will receive
 notification of any non-fatal warnings that occur during
 decoding.
 
 The set of source bands to be read and destination bands to
 be written is determined by calling getSourceBands
 and getDestinationBands on the supplied
 ImageReadParam.  If the lengths of the arrays
 returned by these methods differ, the set of source bands
 contains an index larger that the largest available source
 index, or the set of destination bands contains an index larger
 than the largest legal destination index, an
 IllegalArgumentException is thrown.
 
Thumbnails will be returned in their entirety regardless of the region settings.
 If the supplied ImageReadParam contains
 optional setting values not supported by this reader (e.g.
 source render size or any format-specific settings), those
 values will be ignored.
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IllegalArgumentException - if the set of source and
 destination bands specified by
 param.getSourceBands and
 param.getDestinationBands differ in length or
 include indices that are out of bounds.IllegalArgumentException - if the resulting image
 would have a width or height less than 1.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.param - an ImageReadParam used to control
 the reading process, or null.IIOImage containing the desired portion
 of the image, a set of thumbnails, and associated image
 metadata.public Iterator<IIOImage> readAll(Iterator<? extends ImageReadParam> params) throws IOException
Iterator containing all the images,
 thumbnails, and metadata, starting at the index given by
 getMinIndex, from the input source in the form of
 IIOImage objects.  An Iterator
 containing ImageReadParam objects is supplied; one
 element is consumed for each image read from the input source
 until no more images are available.  If the read param
 Iterator runs out of elements, but there are still
 more images available from the input source, default read
 params are used for the remaining images.
  If params is null, a default read
 param will be used for all images.
 
 The actual BufferedImage referenced by the
 returned IIOImage will be chosen using the
 algorithm defined by the getDestination method.
 
 Any registered IIOReadProgressListener objects
 will be notified by calling their sequenceStarted
 method once.  Then, for each image decoded, there will be a
 call to imageStarted, followed by calls to
 imageProgress as the read progresses, and finally
 to imageComplete.  The
 sequenceComplete method will be called after the
 last image has been decoded.
 IIOReadUpdateListener objects may be updated at
 other times during the read as pixels are decoded.  Finally,
 IIOReadWarningListener objects will receive
 notification of any non-fatal warnings that occur during
 decoding.
 
 The set of source bands to be read and destination bands to
 be written is determined by calling getSourceBands
 and getDestinationBands on the supplied
 ImageReadParam.  If the lengths of the arrays
 returned by these methods differ, the set of source bands
 contains an index larger that the largest available source
 index, or the set of destination bands contains an index larger
 than the largest legal destination index, an
 IllegalArgumentException is thrown.
 
Thumbnails will be returned in their entirety regardless of the region settings.
 If any of the supplied ImageReadParams contain
 optional setting values not supported by this reader (e.g.
 source render size or any format-specific settings), they will
 be ignored.
IllegalStateException - if the input source has not been
 set.IllegalArgumentException - if any
 non-null element of params is not an
 ImageReadParam.IllegalArgumentException - if the set of source and
 destination bands specified by
 param.getSourceBands and
 param.getDestinationBands differ in length or
 include indices that are out of bounds.IllegalArgumentException - if a resulting image would
 have a width or height less than 1.IOException - if an error occurs during reading.params - an Iterator containing
 ImageReadParam objects.Iterator representing the
 contents of the input source as IIOImages.ImageReadParam, 
IIOImagepublic boolean canReadRaster()
true if this plug-in supports reading
 just a Raster of pixel data.
 If this method returns false, calls to
 readRaster or readTileRaster
 will throw an UnsupportedOperationException.
  The default implementation returns false.
true if this plug-in supports reading raw
 Rasters.readRaster(int, javax.imageio.ImageReadParam), 
readTileRaster(int, int, int)public Raster readRaster(int imageIndex, ImageReadParam param) throws IOException
Raster object containing the raw pixel data
 from the image stream, without any color conversion applied.  The
 application must determine how to interpret the pixel data by other
 means.  Any destination or image-type parameters in the supplied
 ImageReadParam object are ignored, but all other
 parameters are used exactly as in the read
 method, except that any destination offset is used as a logical rather
 than a physical offset.  The size of the returned Raster
 will always be that of the source region clipped to the actual image.
 Logical offsets in the stream itself are ignored.
 This method allows formats that normally apply a color conversion, such as JPEG, and formats that do not normally have an associated colorspace, such as remote sensing or medical imaging data, to provide access to raw pixel data.
 Any registered readUpdateListeners are ignored, as
 there is no BufferedImage, but all other listeners are
 called exactly as they are for the read method.
 
 If canReadRaster() returns
 false, this method throws an
 UnsupportedOperationException.
 
 If the supplied ImageReadParam contains
 optional setting values not supported by this reader (e.g.
 source render size or any format-specific settings), they will
 be ignored.
 
 The default implementation throws an
 UnsupportedOperationException.
UnsupportedOperationException - if this plug-in does not
 support reading raw Rasters.IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be read.param - an ImageReadParam used to control
 the reading process, or null.Raster.canReadRaster(), 
read(int), 
Rasterpublic boolean isImageTiled(int imageIndex)
                     throws IOException
true if the image is organized into
 tiles, that is, equal-sized non-overlapping rectangles.
  A reader plug-in may choose whether or not to expose tiling
 that is present in the image as it is stored.  It may even
 choose to advertise tiling when none is explicitly present.  In
 general, tiling should only be advertised if there is some
 advantage (in speed or space) to accessing individual tiles.
 Regardless of whether the reader advertises tiling, it must be
 capable of reading an arbitrary rectangular region specified in
 an ImageReadParam.
 
 A reader for which all images are guaranteed to be tiled,
 or are guaranteed not to be tiled, may return true
 or false respectively without accessing any image
 data.  In such cases, it is not necessary to throw an exception
 even if no input source has been set or the image index is out
 of bounds.
 
 The default implementation just returns false.
IllegalStateException - if an input source is required
 to determine the return value, but none has been set.IndexOutOfBoundsException - if an image must be
 accessed to determine the return value, but the supplied index
 is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.true if the image is tiled.public int getTileWidth(int imageIndex)
                 throws IOException
 The default implementation simply returns
 getWidth(imageIndex), which is correct for
 non-tiled images.  Readers that support tiling should override
 this method.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.public int getTileHeight(int imageIndex)
                  throws IOException
 The default implementation simply returns
 getHeight(imageIndex), which is correct for
 non-tiled images.  Readers that support tiling should override
 this method.
IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.public int getTileGridXOffset(int imageIndex)
                       throws IOException
A reader for which the tile grid X offset always has the same value (usually 0), may return the value without accessing any image data. In such cases, it is not necessary to throw an exception even if no input source has been set or the image index is out of bounds.
The default implementation simply returns 0, which is correct for non-tiled images and tiled images in most formats. Readers that support tiling with non-(0, 0) offsets should override this method.
IllegalStateException - if an input source is required
 to determine the return value, but none has been set.IndexOutOfBoundsException - if an image must be
 accessed to determine the return value, but the supplied index
 is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.public int getTileGridYOffset(int imageIndex)
                       throws IOException
A reader for which the tile grid Y offset always has the same value (usually 0), may return the value without accessing any image data. In such cases, it is not necessary to throw an exception even if no input source has been set or the image index is out of bounds.
The default implementation simply returns 0, which is correct for non-tiled images and tiled images in most formats. Readers that support tiling with non-(0, 0) offsets should override this method.
IllegalStateException - if an input source is required
 to determine the return value, but none has been set.IndexOutOfBoundsException - if an image must be
 accessed to determine the return value, but the supplied index
 is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be queried.public BufferedImage readTile(int imageIndex, int tileX, int tileY) throws IOException
tileX and
 tileY arguments, returning it as a
 BufferedImage.  If the arguments are out of range,
 an IllegalArgumentException is thrown.  If the
 image is not tiled, the values 0, 0 will return the entire
 image; any other values will cause an
 IllegalArgumentException to be thrown.
  This method is merely a convenience equivalent to calling
 read(int, ImageReadParam) with a read param
 specifying a source region having offsets of
 tileX*getTileWidth(imageIndex),
 tileY*getTileHeight(imageIndex) and width and
 height of getTileWidth(imageIndex),
 getTileHeight(imageIndex); and subsampling
 factors of 1 and offsets of 0.  To subsample a tile, call
 read with a read param specifying this region
 and different subsampling parameters.
 
 The default implementation returns the entire image if
 tileX and tileY are 0, or throws
 an IllegalArgumentException otherwise.
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if imageIndex
 is out of bounds.IllegalArgumentException - if the tile indices are
 out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.tileX - the column index (starting with 0) of the tile
 to be retrieved.tileY - the row index (starting with 0) of the tile
 to be retrieved.BufferedImage.public Raster readTileRaster(int imageIndex, int tileX, int tileY) throws IOException
Raster object containing the raw
 pixel data from the tile, without any color conversion applied.
 The application must determine how to interpret the pixel data by other
 means.
  If canReadRaster() returns
 false, this method throws an
 UnsupportedOperationException.
 
 The default implementation checks if reading
 Rasters is supported, and if so calls readRaster(imageIndex, null) if
 tileX and tileY are 0, or throws an
 IllegalArgumentException otherwise.
UnsupportedOperationException - if this plug-in does not
 support reading raw Rasters.IllegalArgumentException - if the tile indices are
 out of bounds.IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if imageIndex
 is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.tileX - the column index (starting with 0) of the tile
 to be retrieved.tileY - the row index (starting with 0) of the tile
 to be retrieved.Raster.readTile(int, int, int), 
readRaster(int, javax.imageio.ImageReadParam), 
Rasterpublic RenderedImage readAsRenderedImage(int imageIndex, ImageReadParam param) throws IOException
RenderedImage object that contains the
 contents of the image indexed by imageIndex.  By
 default, the returned image is simply the
 BufferedImage returned by read(imageIndex,
 param).
  The semantics of this method may differ from those of the
 other read methods in several ways.  First, any
 destination image and/or image type set in the
 ImageReadParam may be ignored.  Second, the usual
 listener calls are not guaranteed to be made, or to be
 meaningful if they are.  This is because the returned image may
 not be fully populated with pixel data at the time it is
 returned, or indeed at any time.
 
 If the supplied ImageReadParam contains
 optional setting values not supported by this reader (e.g.
 source render size or any format-specific settings), they will
 be ignored.
 
 The default implementation just calls
 read(imageIndex, param).
IllegalStateException - if the input source has not been
 set.IndexOutOfBoundsException - if the supplied index is
 out of bounds.IllegalArgumentException - if the set of source and
 destination bands specified by
 param.getSourceBands and
 param.getDestinationBands differ in length or
 include indices that are out of bounds.IllegalArgumentException - if the resulting image
 would have a width or height less than 1.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.param - an ImageReadParam used to control
 the reading process, or null.RenderedImage object providing a view of
 the image.public boolean readerSupportsThumbnails()
true if the image format understood by
 this reader supports thumbnail preview images associated with
 it.  The default implementation returns false.
  If this method returns false,
 hasThumbnails and getNumThumbnails
 will return false and 0,
 respectively, and readThumbnail will throw an
 UnsupportedOperationException, regardless of their
 arguments.
 
A reader that does not support thumbnails need not implement any of the thumbnail-related methods.
true if thumbnails are supported.public boolean hasThumbnails(int imageIndex)
                      throws IOException
true if the given image has thumbnail
 preview images associated with it.  If the format does not
 support thumbnails (readerSupportsThumbnails
 returns false), false will be
 returned regardless of whether an input source has been set or
 whether imageIndex is in bounds.
  The default implementation returns true if
 getNumThumbnails returns a value greater than 0.
IllegalStateException - if the reader supports
 thumbnails but the input source has not been set.IndexOutOfBoundsException - if the reader supports
 thumbnails but imageIndex is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image being queried.true if the given image has thumbnails.public int getNumThumbnails(int imageIndex)
                     throws IOException
readerSupportsThumbnails returns
 false), 0 will be returned regardless
 of whether an input source has been set or whether
 imageIndex is in bounds.
 The default implementation returns 0 without checking its argument.
IllegalStateException - if the reader supports
 thumbnails but the input source has not been set.IndexOutOfBoundsException - if the reader supports
 thumbnails but imageIndex is out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image being queried.public int getThumbnailWidth(int imageIndex,
                             int thumbnailIndex)
                      throws IOException
thumbnailIndex, associated with the image indexed
 by ImageIndex.
  If the reader does not support thumbnails,
 (readerSupportsThumbnails returns
 false), an UnsupportedOperationException
 will be thrown.
 
 The default implementation simply returns
 readThumbnail(imageindex,
 thumbnailIndex).getWidth().  Subclasses should therefore
 override this method if possible in order to avoid forcing the
 thumbnail to be read.
UnsupportedOperationException - if thumbnails are not
 supported.IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if either of the supplied
 indices are out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.thumbnailIndex - the index of the thumbnail to be retrieved.int.public int getThumbnailHeight(int imageIndex,
                              int thumbnailIndex)
                       throws IOException
thumbnailIndex, associated with the image indexed
 by ImageIndex.
  If the reader does not support thumbnails,
 (readerSupportsThumbnails returns
 false), an UnsupportedOperationException
 will be thrown.
 
 The default implementation simply returns
 readThumbnail(imageindex,
 thumbnailIndex).getHeight().  Subclasses should
 therefore override this method if possible in order to avoid
 forcing the thumbnail to be read.
UnsupportedOperationException - if thumbnails are not
 supported.IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if either of the supplied
 indices are out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.thumbnailIndex - the index of the thumbnail to be retrieved.int.public BufferedImage readThumbnail(int imageIndex, int thumbnailIndex) throws IOException
thumbnailIndex, associated with the image indexed
 by ImageIndex as a BufferedImage.
  Any registered IIOReadProgressListener objects
 will be notified by calling their
 thumbnailStarted, thumbnailProgress,
 and thumbnailComplete methods.
 
 If the reader does not support thumbnails,
 (readerSupportsThumbnails returns
 false), an UnsupportedOperationException
 will be thrown regardless of whether an input source has been
 set or whether the indices are in bounds.
 
 The default implementation throws an
 UnsupportedOperationException.
UnsupportedOperationException - if thumbnails are not
 supported.IllegalStateException - if the input source has not been set.IndexOutOfBoundsException - if either of the supplied
 indices are out of bounds.IOException - if an error occurs during reading.imageIndex - the index of the image to be retrieved.thumbnailIndex - the index of the thumbnail to be retrieved.BufferedImage.public void abort()
 Readers should call clearAbortRequest at the
 beginning of each read operation, and poll the value of
 abortRequested regularly during the read.
protected boolean abortRequested()
true if a request to abort the current
 read operation has been made since the reader was instantiated or
 clearAbortRequest was called.true if the current read operation should
 be aborted.abort(), 
clearAbortRequest()protected void clearAbortRequest()
abortRequested will return
 false.abort(), 
abortRequested()public void addIIOReadWarningListener(IIOReadWarningListener listener)
IIOReadWarningListener to the list of
 registered warning listeners.  If listener is
 null, no exception will be thrown and no action
 will be taken.  Messages sent to the given listener will be
 localized, if possible, to match the current
 Locale.  If no Locale has been set,
 warning messages may be localized as the reader sees fit.listener - an IIOReadWarningListener to be registered.removeIIOReadWarningListener(javax.imageio.event.IIOReadWarningListener)public void removeIIOReadWarningListener(IIOReadWarningListener listener)
IIOReadWarningListener from the list of
 registered error listeners.  If the listener was not previously
 registered, or if listener is null,
 no exception will be thrown and no action will be taken.listener - an IIOReadWarningListener to be unregistered.addIIOReadWarningListener(javax.imageio.event.IIOReadWarningListener)public void removeAllIIOReadWarningListeners()
IIOReadWarningListener objects.
  The default implementation sets the
 warningListeners and warningLocales
 instance variables to null.
public void addIIOReadProgressListener(IIOReadProgressListener listener)
IIOReadProgressListener to the list of
 registered progress listeners.  If listener is
 null, no exception will be thrown and no action
 will be taken.listener - an IIOReadProgressListener to be registered.removeIIOReadProgressListener(javax.imageio.event.IIOReadProgressListener)public void removeIIOReadProgressListener(IIOReadProgressListener listener)
IIOReadProgressListener from the list
 of registered progress listeners.  If the listener was not
 previously registered, or if listener is
 null, no exception will be thrown and no action
 will be taken.listener - an IIOReadProgressListener to be unregistered.addIIOReadProgressListener(javax.imageio.event.IIOReadProgressListener)public void removeAllIIOReadProgressListeners()
IIOReadProgressListener objects.
  The default implementation sets the
 progressListeners instance variable to
 null.
public void addIIOReadUpdateListener(IIOReadUpdateListener listener)
IIOReadUpdateListener to the list of
 registered update listeners.  If listener is
 null, no exception will be thrown and no action
 will be taken.  The listener will receive notification of pixel
 updates as images and thumbnails are decoded, including the
 starts and ends of progressive passes.
 If no update listeners are present, the reader may choose to perform fewer updates to the pixels of the destination images and/or thumbnails, which may result in more efficient decoding.
For example, in progressive JPEG decoding each pass contains updates to a set of coefficients, which would have to be transformed into pixel values and converted to an RGB color space for each pass if listeners are present. If no listeners are present, the coefficients may simply be accumulated and the final results transformed and color converted one time only.
 The final results of decoding will be the same whether or
 not intermediate updates are performed.  Thus if only the final
 image is desired it may be preferable not to register any
 IIOReadUpdateListeners.  In general, progressive
 updating is most effective when fetching images over a network
 connection that is very slow compared to local CPU processing;
 over a fast connection, progressive updates may actually slow
 down the presentation of the image.
listener - an IIOReadUpdateListener to be registered.removeIIOReadUpdateListener(javax.imageio.event.IIOReadUpdateListener)public void removeIIOReadUpdateListener(IIOReadUpdateListener listener)
IIOReadUpdateListener from the list of
 registered update listeners.  If the listener was not
 previously registered, or if listener is
 null, no exception will be thrown and no action
 will be taken.listener - an IIOReadUpdateListener to be unregistered.addIIOReadUpdateListener(javax.imageio.event.IIOReadUpdateListener)public void removeAllIIOReadUpdateListeners()
IIOReadUpdateListener objects.
  The default implementation sets the
 updateListeners instance variable to
 null.
protected void processSequenceStarted(int minIndex)
IIOReadProgressListeners by calling
 their sequenceStarted method.  Subclasses may use
 this method as a convenience.minIndex - the lowest index being read.protected void processSequenceComplete()
IIOReadProgressListeners by calling
 their sequenceComplete method.  Subclasses may use
 this method as a convenience.protected void processImageStarted(int imageIndex)
IIOReadProgressListeners by calling their
 imageStarted method.  Subclasses may use this
 method as a convenience.imageIndex - the index of the image about to be read.protected void processImageProgress(float percentageDone)
IIOReadProgressListeners by calling
 their imageProgress method.  Subclasses may use
 this method as a convenience.percentageDone - the current percentage of completion,
 as a float.protected void processImageComplete()
IIOReadProgressListeners by calling their
 imageComplete method.  Subclasses may use this
 method as a convenience.protected void processThumbnailStarted(int imageIndex,
                                       int thumbnailIndex)
IIOReadProgressListeners by calling their
 thumbnailStarted method.  Subclasses may use this
 method as a convenience.imageIndex - the index of the image associated with the
 thumbnail.thumbnailIndex - the index of the thumbnail.protected void processThumbnailProgress(float percentageDone)
IIOReadProgressListeners by calling
 their thumbnailProgress method.  Subclasses may
 use this method as a convenience.percentageDone - the current percentage of completion,
 as a float.protected void processThumbnailComplete()
IIOReadProgressListeners by calling their
 thumbnailComplete method.  Subclasses may use this
 method as a convenience.protected void processReadAborted()
IIOReadProgressListeners by calling their
 readAborted method.  Subclasses may use this
 method as a convenience.protected void processPassStarted(BufferedImage theImage, int pass, int minPass, int maxPass, int minX, int minY, int periodX, int periodY, int[] bands)
IIOReadUpdateListeners by calling their
 passStarted method.  Subclasses may use this
 method as a convenience.theImage - the BufferedImage being updated.pass - the index of the current pass, starting with 0.minPass - the index of the first pass that will be decoded.maxPass - the index of the last pass that will be decoded.minX - the X coordinate of the upper-left pixel included
 in the pass.minY - the X coordinate of the upper-left pixel included
 in the pass.periodX - the horizontal separation between pixels.periodY - the vertical separation between pixels.bands - an array of ints indicating the
 set of affected bands of the destination.protected void processImageUpdate(BufferedImage theImage, int minX, int minY, int width, int height, int periodX, int periodY, int[] bands)
IIOReadUpdateListeners by calling their
 imageUpdate method.  Subclasses may use this
 method as a convenience.theImage - the BufferedImage being updated.minX - the X coordinate of the upper-left pixel included
 in the pass.minY - the X coordinate of the upper-left pixel included
 in the pass.width - the total width of the area being updated, including
 pixels being skipped if periodX > 1.height - the total height of the area being updated,
 including pixels being skipped if periodY > 1.periodX - the horizontal separation between pixels.periodY - the vertical separation between pixels.bands - an array of ints indicating the
 set of affected bands of the destination.protected void processPassComplete(BufferedImage theImage)
IIOReadUpdateListeners by calling their
 passComplete method.  Subclasses may use this
 method as a convenience.theImage - the BufferedImage being updated.protected void processThumbnailPassStarted(BufferedImage theThumbnail, int pass, int minPass, int maxPass, int minX, int minY, int periodX, int periodY, int[] bands)
IIOReadUpdateListeners by calling their
 thumbnailPassStarted method.  Subclasses may use this
 method as a convenience.theThumbnail - the BufferedImage thumbnail
 being updated.pass - the index of the current pass, starting with 0.minPass - the index of the first pass that will be decoded.maxPass - the index of the last pass that will be decoded.minX - the X coordinate of the upper-left pixel included
 in the pass.minY - the X coordinate of the upper-left pixel included
 in the pass.periodX - the horizontal separation between pixels.periodY - the vertical separation between pixels.bands - an array of ints indicating the
 set of affected bands of the destination.protected void processThumbnailUpdate(BufferedImage theThumbnail, int minX, int minY, int width, int height, int periodX, int periodY, int[] bands)
IIOReadUpdateListeners by
 calling their thumbnailUpdate method.  Subclasses may
 use this method as a convenience.theThumbnail - the BufferedImage thumbnail
 being updated.minX - the X coordinate of the upper-left pixel included
 in the pass.minY - the X coordinate of the upper-left pixel included
 in the pass.width - the total width of the area being updated, including
 pixels being skipped if periodX > 1.height - the total height of the area being updated,
 including pixels being skipped if periodY > 1.periodX - the horizontal separation between pixels.periodY - the vertical separation between pixels.bands - an array of ints indicating the
 set of affected bands of the destination.protected void processThumbnailPassComplete(BufferedImage theThumbnail)
IIOReadUpdateListeners by calling their
 thumbnailPassComplete method.  Subclasses may use this
 method as a convenience.theThumbnail - the BufferedImage thumbnail
 being updated.protected void processWarningOccurred(String warning)
IIOReadWarningListeners by calling their
 warningOccurred method.  Subclasses may use this
 method as a convenience.IllegalArgumentException - if warning
 is null.warning - the warning message to send.protected void processWarningOccurred(String baseName, String keyword)
IIOReadWarningListeners by calling their
 warningOccurred method with a string taken
 from a ResourceBundle.  Subclasses may use this
 method as a convenience.IllegalArgumentException - if baseName
 is null.IllegalArgumentException - if keyword
 is null.IllegalArgumentException - if no appropriate
 ResourceBundle may be located.IllegalArgumentException - if the named resource is
 not found in the located ResourceBundle.IllegalArgumentException - if the object retrieved
 from the ResourceBundle is not a
 String.baseName - the base name of a set of
 ResourceBundles containing localized warning
 messages.keyword - the keyword used to index the warning message
 within the set of ResourceBundles.public void reset()
ImageReader to its initial state.
  The default implementation calls setInput(null,
 false), setLocale(null),
 removeAllIIOReadUpdateListeners(),
 removeAllIIOReadWarningListeners(),
 removeAllIIOReadProgressListeners(), and
 clearAbortRequest.
public void dispose()
finalize) subsequent to a call to this method
 is undefined.
 It is important for applications to call this method when they
 know they will no longer be using this ImageReader.
 Otherwise, the reader may continue to hold on to resources
 indefinitely.
 
The default implementation of this method in the superclass does nothing. Subclass implementations should ensure that all resources, especially native resources, are released.
protected static Rectangle getSourceRegion(ImageReadParam param, int srcWidth, int srcHeight)
ImageReadParam.  The actual
 subsampling factors, destination size, and destination offset
 are not taken into consideration, thus further
 clipping must take place.  The computeRegions
 method performs all necessary clipping.param - the ImageReadParam being used, or
 null.srcWidth - the width of the source image.srcHeight - the height of the source image.Rectangle.protected static void computeRegions(ImageReadParam param, int srcWidth, int srcHeight, BufferedImage image, Rectangle srcRegion, Rectangle destRegion)
ImageReadParam into account.  The source region
 begins with the entire source image.  Then that is clipped to
 the source region specified in the ImageReadParam,
 if one is specified.
 If either of the destination offsets are negative, the source region is clipped so that its top left will coincide with the top left of the destination image, taking subsampling into account. Then the result is clipped to the destination image on the right and bottom, if one is specified, taking subsampling and destination offsets into account.
 Similarly, the destination region begins with the source
 image, is translated to the destination offset given in the
 ImageReadParam if there is one, and finally is
 clipped to the destination image, if there is one.
 
 If either the source or destination regions end up having a
 width or height of 0, an IllegalArgumentException
 is thrown.
 
 The getSourceRegion>
 method may be used if only source clipping is desired.
IllegalArgumentException - if srcRegion
 is null.IllegalArgumentException - if dstRegion
 is null.IllegalArgumentException - if the resulting source or
 destination region is empty.param - an ImageReadParam, or null.srcWidth - the width of the source image.srcHeight - the height of the source image.image - a BufferedImage that will be the
 destination image, or null.srcRegion - a Rectangle that will be filled with
 the source region of interest.destRegion - a Rectangle that will be filled with
 the destination region of interest.protected static void checkReadParamBandSettings(ImageReadParam param, int numSrcBands, int numDstBands)
ImageReadParam.  This method may be called as soon
 as the reader knows both the number of bands of the source
 image as it exists in the input stream, and the number of bands
 of the destination image that being written.
  The method retrieves the source and destination band
 setting arrays from param using the getSourceBands
 and getDestinationBandsmethods (or considers them
 to be null if param is
 null).  If the source band setting array is
 null, it is considered to be equal to the array
 { 0, 1, ..., numSrcBands - 1 }, and similarly for
 the destination band setting array.
 
The method then tests that both arrays are equal in length, and that neither array contains a value larger than the largest available band index.
 Any failure results in an
 IllegalArgumentException being thrown; success
 results in the method returning silently.
IllegalArgumentException - if param
 contains an invalid specification of a source and/or
 destination band subset.param - the ImageReadParam being used to read
 the image.numSrcBands - the number of bands of the image as it exists
 int the input source.numDstBands - the number of bands in the destination image
 being written.protected static BufferedImage getDestination(ImageReadParam param, Iterator<ImageTypeSpecifier> imageTypes, int width, int height) throws IIOException
BufferedImage to which decoded pixel
 data should be written.  The image is determined by inspecting
 the supplied ImageReadParam if it is
 non-null; if its getDestination
 method returns a non-null value, that image is
 simply returned.  Otherwise,
 param.getDestinationType method is called to
 determine if a particular image type has been specified.  If
 so, the returned ImageTypeSpecifier is used after
 checking that it is equal to one of those included in
 imageTypes.
  If param is null or the above
 steps have not yielded an image or an
 ImageTypeSpecifier, the first value obtained from
 the imageTypes parameter is used.  Typically, the
 caller will set imageTypes to the value of
 getImageTypes(imageIndex).
 
 Next, the dimensions of the image are determined by a call
 to computeRegions.  The actual width and height of
 the image being decoded are passed in as the width
 and height parameters.
IIOException - if the ImageTypeSpecifier
 specified by param does not match any of the legal
 ones from imageTypes.IllegalArgumentException - if imageTypes
 is null or empty, or if an object not of type
 ImageTypeSpecifier is retrieved from it.IllegalArgumentException - if the resulting image would
 have a width or height less than 1.IllegalArgumentException - if the product of
 width and height is greater than
 Integer.MAX_VALUE.param - an ImageReadParam to be used to get
 the destination image or image type, or null.imageTypes - an Iterator of
 ImageTypeSpecifiers indicating the legal image
 types, with the default first.width - the true width of the image or tile begin decoded.height - the true width of the image or tile being decoded.BufferedImage to which decoded pixel
 data should be written.aicas GmbH, Karlsruhe, Germany —www.aicas.com
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