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	/*
	* Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.imageio;

	import java.awt.Dimension;
	import java.awt.image.BufferedImage;

	/**
	* A class describing how a stream is to be decoded. Instances of
	* this class or its subclasses are used to supply prescriptive
	* "how-to" information to instances of <code>ImageReader</code>.
	*
	* <p> An image encoded as part of a file or stream may be thought of
	* extending out in multiple dimensions: the spatial dimensions of
	* width and height, a number of bands, and a number of progressive
	* decoding passes. This class allows a contiguous (hyper)rectangular
	* subarea of the image in all of these dimensions to be selected for
	* decoding. Additionally, the spatial dimensions may be subsampled
	* discontinuously. Finally, color and format conversions may be
	* specified by controlling the <code>ColorModel</code> and
	* <code>SampleModel</code> of the destination image, either by
	* providing a <code>BufferedImage</code> or by using an
	* <code>ImageTypeSpecifier</code>.
	*
	* <p> An <code>ImageReadParam</code> object is used to specify how an
	* image, or a set of images, will be converted on input from
	* a stream in the context of the Java Image I/O framework. A plug-in for a
	* specific image format will return instances of
	* <code>ImageReadParam</code> from the
	* <code>getDefaultReadParam</code> method of its
	* <code>ImageReader</code> implementation.
	*
	* <p> The state maintained by an instance of
	* <code>ImageReadParam</code> is independent of any particular image
	* being decoded. When actual decoding takes place, the values set in
	* the read param are combined with the actual properties of the image
	* being decoded from the stream and the destination
	* <code>BufferedImage</code> that will receive the decoded pixel
	* data. For example, the source region set using
	* <code>setSourceRegion</code> will first be intersected with the
	* actual valid source area. The result will be translated by the
	* value returned by <code>getDestinationOffset</code>, and the
	* resulting rectangle intersected with the actual valid destination
	* area to yield the destination area that will be written.
	*
	* <p> The parameters specified by an <code>ImageReadParam</code> are
	* applied to an image as follows. First, if a rendering size has
	* been set by <code>setSourceRenderSize</code>, the entire decoded
	* image is rendered at the size given by
	* <code>getSourceRenderSize</code>. Otherwise, the image has its
	* natural size given by <code>ImageReader.getWidth</code> and
	* <code>ImageReader.getHeight</code>.
	*
	* <p> Next, the image is clipped against the source region
	* specified by <code>getSourceXOffset</code>, <code>getSourceYOffset</code>,
	* <code>getSourceWidth</code>, and <code>getSourceHeight</code>.
	*
	* <p> The resulting region is then subsampled according to the
	* factors given in {@link IIOParam#setSourceSubsampling
	* IIOParam.setSourceSubsampling}. The first pixel,
	* the number of pixels per row, and the number of rows all depend
	* on the subsampling settings.
	* Call the minimum X and Y coordinates of the resulting rectangle
	* (<code>minX</code>, <code>minY</code>), its width <code>w</code>
	* and its height <code>h</code>.
	*
	* <p> This rectangle is offset by
	* (<code>getDestinationOffset().x</code>,
	* <code>getDestinationOffset().y</code>) and clipped against the
	* destination bounds. If no destination image has been set, the
	* destination is defined to have a width of
	* <code>getDestinationOffset().x</code> + <code>w</code>, and a
	* height of <code>getDestinationOffset().y</code> + <code>h</code> so
	* that all pixels of the source region may be written to the
	* destination.
	*
	* <p> Pixels that land, after subsampling, within the destination
	* image, and that are written in one of the progressive passes
	* specified by <code>getSourceMinProgressivePass</code> and
	* <code>getSourceNumProgressivePasses</code> are passed along to the
	* next step.
	*
	* <p> Finally, the source samples of each pixel are mapped into
	* destination bands according to the algorithm described in the
	* comment for <code>setDestinationBands</code>.
	*
	* <p> Plug-in writers may extend the functionality of
	* <code>ImageReadParam</code> by providing a subclass that implements
	* additional, plug-in specific interfaces. It is up to the plug-in
	* to document what interfaces are available and how they are to be
	* used. Readers will silently ignore any extended features of an
	* <code>ImageReadParam</code> subclass of which they are not aware.
	* Also, they may ignore any optional features that they normally
	* disable when creating their own <code>ImageReadParam</code>
	* instances via <code>getDefaultReadParam</code>.
	*
	* <p> Note that unless a query method exists for a capability, it must
	* be supported by all <code>ImageReader</code> implementations
	* (<i>e.g.</i> source render size is optional, but subsampling must be
	* supported).
	*
	*
	* @see ImageReader
	* @see ImageWriter
	* @see ImageWriteParam
	*/
	public class ImageReadParam extends IIOParam {

	/**
	* <code>true</code> if this <code>ImageReadParam</code> allows
	* the source rendering dimensions to be set. By default, the
	* value is <code>false</code>. Subclasses must set this value
	* manually.
	*
	* <p> <code>ImageReader</code>s that do not support setting of
	* the source render size should set this value to
	* <code>false</code>.
	*/
	protected boolean canSetSourceRenderSize = false;

	/**
	* The desired rendering width and height of the source, if
	* <code>canSetSourceRenderSize</code> is <code>true</code>, or
	* <code>null</code>.
	*
	* <p> <code>ImageReader</code>s that do not support setting of
	* the source render size may ignore this value.
	*/
	protected Dimension sourceRenderSize = null;

	/**
	* The current destination <code>BufferedImage</code>, or
	* <code>null</code> if none has been set. By default, the value
	* is <code>null</code>.
	*/
	protected BufferedImage destination = null;

	/**
	* The set of destination bands to be used, as an array of
	* <code>int</code>s. By default, the value is <code>null</code>,
	* indicating all destination bands should be written in order.
	*/
	protected int[] destinationBands = null;

	/**
	* The minimum index of a progressive pass to read from the
	* source. By default, the value is set to 0, which indicates
	* that passes starting with the first available pass should be
	* decoded.
	*
	* <p> Subclasses should ensure that this value is
	* non-negative.
	*/
	protected int minProgressivePass = 0;

	/**
	* The maximum number of progressive passes to read from the
	* source. By default, the value is set to
	* <code>Integer.MAX_VALUE</code>, which indicates that passes up
	* to and including the last available pass should be decoded.
	*
	* <p> Subclasses should ensure that this value is positive.
	* Additionally, if the value is not
	* <code>Integer.MAX_VALUE</code>, then <code>minProgressivePass +
	* numProgressivePasses - 1</code> should not exceed
	* <code>Integer.MAX_VALUE</code>.
	*/
	protected int numProgressivePasses = Integer.MAX_VALUE;

	/**
	* Constructs an <code>ImageReadParam</code>.
	*/
	public ImageReadParam() {}

	// Comment inherited
	public void setDestinationType(ImageTypeSpecifier destinationType) {
	super.setDestinationType(destinationType);
	setDestination(null);
	}

	/**
	* Supplies a <code>BufferedImage</code> to be used as the
	* destination for decoded pixel data. The currently set image
	* will be written to by the <code>read</code>,
	* <code>readAll</code>, and <code>readRaster</code> methods, and
	* a reference to it will be returned by those methods.
	*
	* <p> Pixel data from the aforementioned methods will be written
	* starting at the offset specified by
	* <code>getDestinationOffset</code>.
	*
	* <p> If <code>destination</code> is <code>null</code>, a
	* newly-created <code>BufferedImage</code> will be returned by
	* those methods.
	*
	* <p> At the time of reading, the image is checked to verify that
	* its <code>ColorModel</code> and <code>SampleModel</code>
	* correspond to one of the <code>ImageTypeSpecifier</code>s
	* returned from the <code>ImageReader</code>'s
	* <code>getImageTypes</code> method. If it does not, the reader
	* will throw an <code>IIOException</code>.
	*
	* @param destination the BufferedImage to be written to, or
	* <code>null</code>.
	*
	* @see #getDestination
	*/
	public void setDestination(BufferedImage destination) {
	this.destination = destination;
	}

	/**
	* Returns the <code>BufferedImage</code> currently set by the
	* <code>setDestination</code> method, or <code>null</code>
	* if none is set.
	*
	* @return the BufferedImage to be written to.
	*
	* @see #setDestination
	*/
	public BufferedImage getDestination() {
	return destination;
	}

	/**
	* Sets the indices of the destination bands where data
	* will be placed. Duplicate indices are not allowed.
	*
	* <p> A <code>null</code> value indicates that all destination
	* bands will be used.
	*
	* <p> Choosing a destination band subset will not affect the
	* number of bands in the output image of a read if no destination
	* image is specified; the created destination image will still
	* have the same number of bands as if this method had never been
	* called. If a different number of bands in the destination
	* image is desired, an image must be supplied using the
	* <code>ImageReadParam.setDestination</code> method.
	*
	* <p> At the time of reading or writing, an
	* <code>IllegalArgumentException</code> will be thrown by the
	* reader or writer if a value larger than the largest destination
	* band index has been specified, or if the number of source bands
	* and destination bands to be used differ. The
	* <code>ImageReader.checkReadParamBandSettings</code> method may
	* be used to automate this test.
	*
	* @param destinationBands an array of integer band indices to be
	* used.
	*
	* @exception IllegalArgumentException if <code>destinationBands</code>
	* contains a negative or duplicate value.
	*
	* @see #getDestinationBands
	* @see #getSourceBands
	* @see ImageReader#checkReadParamBandSettings
	*/
	public void setDestinationBands(int[] destinationBands) {
	if (destinationBands == null) {
	this.destinationBands = null;
	} else {
	int numBands = destinationBands.length;
	for (int i = 0; i < numBands; i++) {
	int band = destinationBands[i];
	if (band < 0) {
	throw new IllegalArgumentException("Band value < 0!");
	}
	for (int j = i + 1; j < numBands; j++) {
	if (band == destinationBands[j]) {
	throw new IllegalArgumentException("Duplicate band value!");
	}
	}
	}
	this.destinationBands = (int[])destinationBands.clone();
	}
	}

	/**
	* Returns the set of band indices where data will be placed.
	* If no value has been set, <code>null</code> is returned to
	* indicate that all destination bands will be used.
	*
	* @return the indices of the destination bands to be used,
	* or <code>null</code>.
	*
	* @see #setDestinationBands
	*/
	public int[] getDestinationBands() {
	if (destinationBands == null) {
	return null;
	} else {
	return (int[])(destinationBands.clone());
	}
	}

	/**
	* Returns <code>true</code> if this reader allows the source
	* image to be rendered at an arbitrary size as part of the
	* decoding process, by means of the
	* <code>setSourceRenderSize</code> method. If this method
	* returns <code>false</code>, calls to
	* <code>setSourceRenderSize</code> will throw an
	* <code>UnsupportedOperationException</code>.
	*
	* @return <code>true</code> if setting source rendering size is
	* supported.
	*
	* @see #setSourceRenderSize
	*/
	public boolean canSetSourceRenderSize() {
	return canSetSourceRenderSize;
	}

	/**
	* If the image is able to be rendered at an arbitrary size, sets
	* the source width and height to the supplied values. Note that
	* the values returned from the <code>getWidth</code> and
	* <code>getHeight</code> methods on <code>ImageReader</code> are
	* not affected by this method; they will continue to return the
	* default size for the image. Similarly, if the image is also
	* tiled the tile width and height are given in terms of the default
	* size.
	*
	* <p> Typically, the width and height should be chosen such that
	* the ratio of width to height closely approximates the aspect
	* ratio of the image, as returned from
	* <code>ImageReader.getAspectRatio</code>.
	*
	* <p> If this plug-in does not allow the rendering size to be
	* set, an <code>UnsupportedOperationException</code> will be
	* thrown.
	*
	* <p> To remove the render size setting, pass in a value of
	* <code>null</code> for <code>size</code>.
	*
	* @param size a <code>Dimension</code> indicating the desired
	* width and height.
	*
	* @exception IllegalArgumentException if either the width or the
	* height is negative or 0.
	* @exception UnsupportedOperationException if image resizing
	* is not supported by this plug-in.
	*
	* @see #getSourceRenderSize
	* @see ImageReader#getWidth
	* @see ImageReader#getHeight
	* @see ImageReader#getAspectRatio
	*/
	public void setSourceRenderSize(Dimension size)
	throws UnsupportedOperationException {
	if (!canSetSourceRenderSize()) {
	throw new UnsupportedOperationException
	("Can't set source render size!");
	}

	if (size == null) {
	this.sourceRenderSize = null;
	} else {
	if (size.width <= 0 \|\| size.height <= 0) {
	throw new IllegalArgumentException("width or height <= 0!");
	}
	this.sourceRenderSize = (Dimension)size.clone();
	}
	}

	/**
	* Returns the width and height of the source image as it
	* will be rendered during decoding, if they have been set via the
	* <code>setSourceRenderSize</code> method. A
	* <code>null</code>value indicates that no setting has been made.
	*
	* @return the rendered width and height of the source image
	* as a <code>Dimension</code>.
	*
	* @see #setSourceRenderSize
	*/
	public Dimension getSourceRenderSize() {
	return (sourceRenderSize == null) ?
	null : (Dimension)sourceRenderSize.clone();
	}

	/**
	* Sets the range of progressive passes that will be decoded.
	* Passes outside of this range will be ignored.
	*
	* <p> A progressive pass is a re-encoding of the entire image,
	* generally at progressively higher effective resolutions, but
	* requiring greater transmission bandwidth. The most common use
	* of progressive encoding is found in the JPEG format, where
	* successive passes include more detailed representations of the
	* high-frequency image content.
	*
	* <p> The actual number of passes to be decoded is determined
	* during decoding, based on the number of actual passes available
	* in the stream. Thus if <code>minPass + numPasses - 1</code> is
	* larger than the index of the last available passes, decoding
	* will end with that pass.
	*
	* <p> A value of <code>numPasses</code> of
	* <code>Integer.MAX_VALUE</code> indicates that all passes from
	* <code>minPass</code> forward should be read. Otherwise, the
	* index of the last pass (<i>i.e.</i>, <code>minPass + numPasses
	* - 1</code>) must not exceed <code>Integer.MAX_VALUE</code>.
	*
	* <p> There is no <code>unsetSourceProgressivePasses</code>
	* method; the same effect may be obtained by calling
	* <code>setSourceProgressivePasses(0, Integer.MAX_VALUE)</code>.
	*
	* @param minPass the index of the first pass to be decoded.
	* @param numPasses the maximum number of passes to be decoded.
	*
	* @exception IllegalArgumentException if <code>minPass</code> is
	* negative, <code>numPasses</code> is negative or 0, or
	* <code>numPasses</code> is smaller than
	* <code>Integer.MAX_VALUE</code> but <code>minPass +
	* numPasses - 1</code> is greater than
	* <code>INTEGER.MAX_VALUE</code>.
	*
	* @see #getSourceMinProgressivePass
	* @see #getSourceMaxProgressivePass
	*/
	public void setSourceProgressivePasses(int minPass, int numPasses) {
	if (minPass < 0) {
	throw new IllegalArgumentException("minPass < 0!");
	}
	if (numPasses <= 0) {
	throw new IllegalArgumentException("numPasses <= 0!");
	}
	if ((numPasses != Integer.MAX_VALUE) &&
	(((minPass + numPasses - 1) & 0x80000000) != 0)) {
	throw new IllegalArgumentException
	("minPass + numPasses - 1 > INTEGER.MAX_VALUE!");
	}

	this.minProgressivePass = minPass;
	this.numProgressivePasses = numPasses;
	}

	/**
	* Returns the index of the first progressive pass that will be
	* decoded. If no value has been set, 0 will be returned (which is
	* the correct value).
	*
	* @return the index of the first pass that will be decoded.
	*
	* @see #setSourceProgressivePasses
	* @see #getSourceNumProgressivePasses
	*/
	public int getSourceMinProgressivePass() {
	return minProgressivePass;
	}

	/**
	* If <code>getSourceNumProgressivePasses</code> is equal to
	* <code>Integer.MAX_VALUE</code>, returns
	* <code>Integer.MAX_VALUE</code>. Otherwise, returns
	* <code>getSourceMinProgressivePass() +
	* getSourceNumProgressivePasses() - 1</code>.
	*
	* @return the index of the last pass to be read, or
	* <code>Integer.MAX_VALUE</code>.
	*/
	public int getSourceMaxProgressivePass() {
	if (numProgressivePasses == Integer.MAX_VALUE) {
	return Integer.MAX_VALUE;
	} else {
	return minProgressivePass + numProgressivePasses - 1;
	}
	}

	/**
	* Returns the number of the progressive passes that will be
	* decoded. If no value has been set,
	* <code>Integer.MAX_VALUE</code> will be returned (which is the
	* correct value).
	*
	* @return the number of the passes that will be decoded.
	*
	* @see #setSourceProgressivePasses
	* @see #getSourceMinProgressivePass
	*/
	public int getSourceNumProgressivePasses() {
	return numProgressivePasses;
	}
	}

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