com.twelvemonkeys.imageio
Class ImageWriterBase

java.lang.Object
  javax.imageio.ImageWriter
      com.twelvemonkeys.imageio.ImageWriterBase

All Implemented Interfaces:

ImageTranscoder

public abstract class ImageWriterBase
extends ImageWriter

Abstract base class for image writers.

Version:

$Id: ImageWriterBase.java,v 1.0 Sep 24, 2007 12:22:28 AM haraldk Exp$

Author:

Harald Kuhr, last modified by $Author: haraldk$

Field Summary

protected ImageOutputStream

imageOutput For convenience.

Fields inherited from class javax.imageio.ImageWriter

availableLocales, locale, originatingProvider, output, progressListeners, warningListeners, warningLocales

Constructor Summary

protected

ImageWriterBase(ImageWriterSpi provider) Constructs an ImageWriter and sets its originatingProvider instance variable to the supplied value.

Method Summary

protected void	assertOutput() Makes sure output is set.
IIOMetadata	convertStreamMetadata(IIOMetadata inData, ImageWriteParam param) Returns null
protected static BufferedImage	fakeAOI(BufferedImage pImage, ImageWriteParam pParam) Utility method for getting the area of interest (AOI) of an image.
protected static Image	fakeSubsampling(Image pImage, ImageWriteParam pParam) Utility method for getting the subsampled image.
IIOMetadata	getDefaultStreamMetadata(ImageWriteParam param) Returns null
String	getFormatName()
protected static Rectangle	getSourceRegion(ImageWriteParam pParam, int pWidth, int pHeight)
void	reset()
protected void	resetMembers()
void	setOutput(Object output)

Methods inherited from class javax.imageio.ImageWriter

abort, abortRequested, addIIOWriteProgressListener, addIIOWriteWarningListener, canInsertEmpty, canInsertImage, canRemoveImage, canReplaceImageMetadata, canReplacePixels, canReplaceStreamMetadata, canWriteEmpty, canWriteRasters, canWriteSequence, clearAbortRequest, convertImageMetadata, dispose, endInsertEmpty, endReplacePixels, endWriteEmpty, endWriteSequence, getAvailableLocales, getDefaultImageMetadata, getDefaultWriteParam, getLocale, getNumThumbnailsSupported, getOriginatingProvider, getOutput, getPreferredThumbnailSizes, prepareInsertEmpty, prepareReplacePixels, prepareWriteEmpty, prepareWriteSequence, processImageComplete, processImageProgress, processImageStarted, processThumbnailComplete, processThumbnailProgress, processThumbnailStarted, processWarningOccurred, processWarningOccurred, processWriteAborted, removeAllIIOWriteProgressListeners, removeAllIIOWriteWarningListeners, removeIIOWriteProgressListener, removeIIOWriteWarningListener, removeImage, replaceImageMetadata, replacePixels, replacePixels, replaceStreamMetadata, setLocale, write, write, write, writeInsert, writeToSequence

Methods inherited from class java.lang.Object

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

Field Detail

imageOutput

protected ImageOutputStream imageOutput

For convenience. Only set if the output is an ImageInputStream.

See Also:

setOutput(Object)

Constructor Detail

ImageWriterBase

protected ImageWriterBase(ImageWriterSpi provider)

Constructs an ImageWriter and sets its originatingProvider instance variable to the supplied value.

Subclasses that make use of extensions should provide a constructor with signature (ImageWriterSpi, Object) in order to retrieve the extension object. If the extension object is unsuitable, an IllegalArgumentException should be thrown.

Parameters:

provider - the ImageWriterSpi that is constructing this object, or null.

Method Detail

getFormatName

public String getFormatName()
                     throws IOException

Throws:

IOException

setOutput

public void setOutput(Object output)

Overrides:

setOutput in class ImageWriter

assertOutput

protected void assertOutput()

Makes sure output is set.

Throws:

IllegalStateException - if getOutput() == null.

reset

public void reset()

Overrides:

reset in class ImageWriter

resetMembers

protected void resetMembers()

getDefaultStreamMetadata

public IIOMetadata getDefaultStreamMetadata(ImageWriteParam param)

Returns null

Specified by:

getDefaultStreamMetadata in class ImageWriter

Parameters:

param - ignored.

Returns:

null.

convertStreamMetadata

public IIOMetadata convertStreamMetadata(IIOMetadata inData,
                                         ImageWriteParam param)

Returns null

Specified by:

convertStreamMetadata in interface ImageTranscoder

Specified by:

convertStreamMetadata in class ImageWriter

Parameters:

inData - ignored.

param - ignored.

Returns:

null.

getSourceRegion

protected static Rectangle getSourceRegion(ImageWriteParam pParam,
                                           int pWidth,
                                           int pHeight)

fakeAOI

protected static BufferedImage fakeAOI(BufferedImage pImage,
                                       ImageWriteParam pParam)

Utility method for getting the area of interest (AOI) of an image. The AOI is defined by the IIOParam.setSourceRegion(java.awt.Rectangle) method.

Note: If it is possible for the reader to read the AOI directly, such a method should be used instead, for efficiency.

Parameters:

pImage - the image to get AOI from

pParam - the param optionally specifying the AOI

Returns:

a BufferedImage containing the area of interest (source region), or the original image, if no source region was set, or pParam was null

fakeSubsampling

protected static Image fakeSubsampling(Image pImage,
                                       ImageWriteParam pParam)

Utility method for getting the subsampled image. The subsampling is defined by the IIOParam.setSourceSubsampling(int, int, int, int) method.

NOTE: This method does not take the subsampling offsets into consideration.

Note: If it is possible for the reader to subsample directly, such a method should be used instead, for efficiency.

Parameters:

pImage - the image to subsample

pParam - the param optionally specifying subsampling

Returns:

an Image containing the subsampled image, or the original image, if no subsampling was specified, or pParam was null