| /* |
| * Copyright (c) 1999, 2014, 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}. |
| * |
| * <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} and |
| * {@code SampleModel} of the destination image, either by |
| * providing a {@code BufferedImage} or by using an |
| * {@code ImageTypeSpecifier}. |
| * |
| * <p> An {@code ImageReadParam} 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} from the |
| * {@code getDefaultReadParam} method of its |
| * {@code ImageReader} implementation. |
| * |
| * <p> The state maintained by an instance of |
| * {@code ImageReadParam} 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} that will receive the decoded pixel |
| * data. For example, the source region set using |
| * {@code setSourceRegion} will first be intersected with the |
| * actual valid source area. The result will be translated by the |
| * value returned by {@code getDestinationOffset}, 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} are |
| * applied to an image as follows. First, if a rendering size has |
| * been set by {@code setSourceRenderSize}, the entire decoded |
| * image is rendered at the size given by |
| * {@code getSourceRenderSize}. Otherwise, the image has its |
| * natural size given by {@code ImageReader.getWidth} and |
| * {@code ImageReader.getHeight}. |
| * |
| * <p> Next, the image is clipped against the source region |
| * specified by {@code getSourceXOffset}, {@code getSourceYOffset}, |
| * {@code getSourceWidth}, and {@code getSourceHeight}. |
| * |
| * <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 minY}), its width {@code w} |
| * and its height {@code h}. |
| * |
| * <p> This rectangle is offset by |
| * ({@code getDestinationOffset().x}, |
| * {@code getDestinationOffset().y}) 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 w}, and a |
| * height of {@code getDestinationOffset().y} + {@code h} 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} and |
| * {@code getSourceNumProgressivePasses} 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}. |
| * |
| * <p> Plug-in writers may extend the functionality of |
| * {@code ImageReadParam} 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} subclass of which they are not aware. |
| * Also, they may ignore any optional features that they normally |
| * disable when creating their own {@code ImageReadParam} |
| * instances via {@code getDefaultReadParam}. |
| * |
| * <p> Note that unless a query method exists for a capability, it must |
| * be supported by all {@code ImageReader} 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} if this {@code ImageReadParam} allows |
| * the source rendering dimensions to be set. By default, the |
| * value is {@code false}. Subclasses must set this value |
| * manually. |
| * |
| * <p> {@code ImageReader}s that do not support setting of |
| * the source render size should set this value to |
| * {@code false}. |
| */ |
| protected boolean canSetSourceRenderSize = false; |
| |
| /** |
| * The desired rendering width and height of the source, if |
| * {@code canSetSourceRenderSize} is {@code true}, or |
| * {@code null}. |
| * |
| * <p> {@code ImageReader}s that do not support setting of |
| * the source render size may ignore this value. |
| */ |
| protected Dimension sourceRenderSize = null; |
| |
| /** |
| * The current destination {@code BufferedImage}, or |
| * {@code null} if none has been set. By default, the value |
| * is {@code null}. |
| */ |
| protected BufferedImage destination = null; |
| |
| /** |
| * The set of destination bands to be used, as an array of |
| * {@code int}s. By default, the value is {@code null}, |
| * 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}, 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}, then |
| * {@code minProgressivePass + numProgressivePasses - 1} |
| * should not exceed |
| * {@code Integer.MAX_VALUE}. |
| */ |
| protected int numProgressivePasses = Integer.MAX_VALUE; |
| |
| /** |
| * Constructs an {@code ImageReadParam}. |
| */ |
| public ImageReadParam() {} |
| |
| // Comment inherited |
| public void setDestinationType(ImageTypeSpecifier destinationType) { |
| super.setDestinationType(destinationType); |
| setDestination(null); |
| } |
| |
| /** |
| * Supplies a {@code BufferedImage} to be used as the |
| * destination for decoded pixel data. The currently set image |
| * will be written to by the {@code read}, |
| * {@code readAll}, and {@code readRaster} 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}. |
| * |
| * <p> If {@code destination} is {@code null}, a |
| * newly-created {@code BufferedImage} will be returned by |
| * those methods. |
| * |
| * <p> At the time of reading, the image is checked to verify that |
| * its {@code ColorModel} and {@code SampleModel} |
| * correspond to one of the {@code ImageTypeSpecifier}s |
| * returned from the {@code ImageReader}'s |
| * {@code getImageTypes} method. If it does not, the reader |
| * will throw an {@code IIOException}. |
| * |
| * @param destination the BufferedImage to be written to, or |
| * {@code null}. |
| * |
| * @see #getDestination |
| */ |
| public void setDestination(BufferedImage destination) { |
| this.destination = destination; |
| } |
| |
| /** |
| * Returns the {@code BufferedImage} currently set by the |
| * {@code setDestination} method, or {@code null} |
| * 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} 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} method. |
| * |
| * <p> At the time of reading or writing, an |
| * {@code IllegalArgumentException} 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} method may |
| * be used to automate this test. |
| * |
| * @param destinationBands an array of integer band indices to be |
| * used. |
| * |
| * @exception IllegalArgumentException if {@code destinationBands} |
| * 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 = destinationBands.clone(); |
| } |
| } |
| |
| /** |
| * Returns the set of band indices where data will be placed. |
| * If no value has been set, {@code null} is returned to |
| * indicate that all destination bands will be used. |
| * |
| * @return the indices of the destination bands to be used, |
| * or {@code null}. |
| * |
| * @see #setDestinationBands |
| */ |
| public int[] getDestinationBands() { |
| if (destinationBands == null) { |
| return null; |
| } else { |
| return destinationBands.clone(); |
| } |
| } |
| |
| /** |
| * Returns {@code true} 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} method. If this method |
| * returns {@code false}, calls to |
| * {@code setSourceRenderSize} will throw an |
| * {@code UnsupportedOperationException}. |
| * |
| * @return {@code true} 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} and |
| * {@code getHeight} methods on {@code ImageReader} 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}. |
| * |
| * <p> If this plug-in does not allow the rendering size to be |
| * set, an {@code UnsupportedOperationException} will be |
| * thrown. |
| * |
| * <p> To remove the render size setting, pass in a value of |
| * {@code null} for {@code size}. |
| * |
| * @param size a {@code Dimension} 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} method. A |
| * {@code null} value indicates that no setting has been made. |
| * |
| * @return the rendered width and height of the source image |
| * as a {@code Dimension}. |
| * |
| * @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} is |
| * larger than the index of the last available passes, decoding |
| * will end with that pass. |
| * |
| * <p> A value of {@code numPasses} of |
| * {@code Integer.MAX_VALUE} indicates that all passes from |
| * {@code minPass} forward should be read. Otherwise, the |
| * index of the last pass (<i>i.e.</i>, {@code minPass + numPasses - 1}) |
| * must not exceed {@code Integer.MAX_VALUE}. |
| * |
| * <p> There is no {@code unsetSourceProgressivePasses} |
| * method; the same effect may be obtained by calling |
| * {@code setSourceProgressivePasses(0, Integer.MAX_VALUE)}. |
| * |
| * @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} is |
| * negative, {@code numPasses} is negative or 0, or |
| * {@code numPasses} is smaller than |
| * {@code Integer.MAX_VALUE} but |
| * {@code minPass + numPasses - 1} is greater than |
| * {@code INTEGER.MAX_VALUE}. |
| * |
| * @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} is equal to |
| * {@code Integer.MAX_VALUE}, returns |
| * {@code Integer.MAX_VALUE}. Otherwise, returns |
| * {@code getSourceMinProgressivePass() + |
| * getSourceNumProgressivePasses() - 1}. |
| * |
| * @return the index of the last pass to be read, or |
| * {@code Integer.MAX_VALUE}. |
| */ |
| 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} 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; |
| } |
| } |