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	/*
	* Copyright (c) 2000, 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.event;

	import java.awt.image.BufferedImage;
	import java.util.EventListener;
	import javax.imageio.ImageReader;

	/**
	* An interface used by <code>ImageReader</code> implementations to
	* notify callers of their image and thumbnail reading methods of
	* pixel updates.
	*
	* @see javax.imageio.ImageReader#addIIOReadUpdateListener
	* @see javax.imageio.ImageReader#removeIIOReadUpdateListener
	*
	*/
	public interface IIOReadUpdateListener extends EventListener {

	/**
	* Reports that the current read operation is about to begin a
	* progressive pass. Readers of formats that support progressive
	* encoding should use this to notify clients when each pass is
	* completed when reading a progressively encoded image.
	*
	* <p> An estimate of the area that will be updated by the pass is
	* indicated by the <code>minX</code>, <code>minY</code>,
	* <code>width</code>, and <code>height</code> parameters. If the
	* pass is interlaced, that is, it only updates selected rows or
	* columns, the <code>periodX</code> and <code>periodY</code>
	* parameters will indicate the degree of subsampling. The set of
	* bands that may be affected is indicated by the value of
	* <code>bands</code>.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	* @param theImage the <code>BufferedImage</code> being updated.
	* @param pass the number of the pass that is about to begin,
	* starting with 0.
	* @param minPass the index of the first pass that will be decoded.
	* @param maxPass the index of the last pass that will be decoded.
	* @param minX the X coordinate of the leftmost updated column
	* of pixels.
	* @param minY the Y coordinate of the uppermost updated row
	* of pixels.
	* @param periodX the horizontal spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param periodY the vertical spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param bands an array of <code>int</code>s indicating the the
	* set bands that may be updated.
	*/
	void passStarted(ImageReader source,
	BufferedImage theImage,
	int pass,
	int minPass, int maxPass,
	int minX, int minY,
	int periodX, int periodY,
	int[] bands);

	/**
	* Reports that a given region of the image has been updated.
	* The application might choose to redisplay the specified area,
	* for example, in order to provide a progressive display effect,
	* or perform other incremental processing.
	*
	* <p> Note that different image format readers may produce
	* decoded pixels in a variety of different orders. Many readers
	* will produce pixels in a simple top-to-bottom,
	* left-to-right-order, but others may use multiple passes of
	* interlacing, tiling, etc. The sequence of updates may even
	* differ from call to call depending on network speeds, for
	* example. A call to this method does not guarantee that all the
	* specified pixels have actually been updated, only that some
	* activity has taken place within some subregion of the one
	* specified.
	*
	* <p> The particular <code>ImageReader</code> implementation may
	* choose how often to provide updates. Each update specifies
	* that a given region of the image has been updated since the
	* last update. A region is described by its spatial bounding box
	* (<code>minX</code>, <code>minY</code>, <code>width</code>, and
	* <code>height</code>); X and Y subsampling factors
	* (<code>periodX</code> and <code>periodY</code>); and a set of
	* updated bands (<code>bands</code>). For example, the update:
	*
	* <pre>
	* minX = 10
	* minY = 20
	* width = 3
	* height = 4
	* periodX = 2
	* periodY = 3
	* bands = { 1, 3 }
	* </pre>
	*
	* would indicate that bands 1 and 3 of the following pixels were
	* updated:
	*
	* <pre>
	* (10, 20) (12, 20) (14, 20)
	* (10, 23) (12, 23) (14, 23)
	* (10, 26) (12, 26) (14, 26)
	* (10, 29) (12, 29) (14, 29)
	* </pre>
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param theImage the <code>BufferedImage</code> being updated.
	* @param minX the X coordinate of the leftmost updated column
	* of pixels.
	* @param minY the Y coordinate of the uppermost updated row
	* of pixels.
	* @param width the number of updated pixels horizontally.
	* @param height the number of updated pixels vertically.
	* @param periodX the horizontal spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param periodY the vertical spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param bands an array of <code>int</code>s indicating which
	* bands are being updated.
	*/
	void imageUpdate(ImageReader source,
	BufferedImage theImage,
	int minX, int minY,
	int width, int height,
	int periodX, int periodY,
	int[] bands);

	/**
	* Reports that the current read operation has completed a
	* progressive pass. Readers of formats that support
	* progressive encoding should use this to notify clients when
	* each pass is completed when reading a progressively
	* encoded image.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	* @param theImage the <code>BufferedImage</code> being updated.
	*
	* @see javax.imageio.ImageReadParam#setSourceProgressivePasses(int, int)
	*/
	void passComplete(ImageReader source, BufferedImage theImage);

	/**
	* Reports that the current thumbnail read operation is about to
	* begin a progressive pass. Readers of formats that support
	* progressive encoding should use this to notify clients when
	* each pass is completed when reading a progressively encoded
	* thumbnail image.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	* @param theThumbnail the <code>BufferedImage</code> thumbnail
	* being updated.
	* @param pass the number of the pass that is about to begin,
	* starting with 0.
	* @param minPass the index of the first pass that will be decoded.
	* @param maxPass the index of the last pass that will be decoded.
	* @param minX the X coordinate of the leftmost updated column
	* of pixels.
	* @param minY the Y coordinate of the uppermost updated row
	* of pixels.
	* @param periodX the horizontal spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param periodY the vertical spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param bands an array of <code>int</code>s indicating the the
	* set bands that may be updated.
	*
	* @see #passStarted
	*/
	void thumbnailPassStarted(ImageReader source,
	BufferedImage theThumbnail,
	int pass,
	int minPass, int maxPass,
	int minX, int minY,
	int periodX, int periodY,
	int[] bands);

	/**
	* Reports that a given region of a thumbnail image has been updated.
	* The application might choose to redisplay the specified area,
	* for example, in order to provide a progressive display effect,
	* or perform other incremental processing.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param theThumbnail the <code>BufferedImage</code> thumbnail
	* being updated.
	* @param minX the X coordinate of the leftmost updated column
	* of pixels.
	* @param minY the Y coordinate of the uppermost updated row
	* of pixels.
	* @param width the number of updated pixels horizontally.
	* @param height the number of updated pixels vertically.
	* @param periodX the horizontal spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param periodY the vertical spacing between updated pixels;
	* a value of 1 means no gaps.
	* @param bands an array of <code>int</code>s indicating which
	* bands are being updated.
	*
	* @see #imageUpdate
	*/
	void thumbnailUpdate(ImageReader source,
	BufferedImage theThumbnail,
	int minX, int minY,
	int width, int height,
	int periodX, int periodY,
	int[] bands);

	/**
	* Reports that the current thumbnail read operation has completed
	* a progressive pass. Readers of formats that support
	* progressive encoding should use this to notify clients when
	* each pass is completed when reading a progressively encoded
	* thumbnail image.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	* @param theThumbnail the <code>BufferedImage</code> thumbnail
	* being updated.
	*
	* @see #passComplete
	*/
	void thumbnailPassComplete(ImageReader source, BufferedImage theThumbnail);
	}

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