Java tutorial
/* * Copyright (c) 1998, 2018, 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 java.awt.image; /** * This class represents image data which is stored in a pixel interleaved * fashion and for * which each sample of a pixel occupies one data element of the DataBuffer. * It subclasses ComponentSampleModel but provides a more efficient * implementation for accessing pixel interleaved image data than is provided * by ComponentSampleModel. This class * stores sample data for all bands in a single bank of the * DataBuffer. Accessor methods are provided so that image data can be * manipulated directly. Pixel stride is the number of * data array elements between two samples for the same band on the same * scanline. Scanline stride is the number of data array elements between * a given sample and the corresponding sample in the same column of the next * scanline. Band offsets denote the number * of data array elements from the first data array element of the bank * of the DataBuffer holding each band to the first sample of the band. * The bands are numbered from 0 to N-1. * Bank indices denote the correspondence between a bank of the data buffer * and a band of image data. * This class supports * {@link DataBuffer#TYPE_BYTE TYPE_BYTE}, * {@link DataBuffer#TYPE_USHORT TYPE_USHORT}, * {@link DataBuffer#TYPE_SHORT TYPE_SHORT}, * {@link DataBuffer#TYPE_INT TYPE_INT}, * {@link DataBuffer#TYPE_FLOAT TYPE_FLOAT} and * {@link DataBuffer#TYPE_DOUBLE TYPE_DOUBLE} datatypes. */ public class PixelInterleavedSampleModel extends ComponentSampleModel { /** * Constructs a PixelInterleavedSampleModel with the specified parameters. * The number of bands will be given by the length of the bandOffsets * array. * @param dataType The data type for storing samples. * @param w The width (in pixels) of the region of * image data described. * @param h The height (in pixels) of the region of * image data described. * @param pixelStride The pixel stride of the image data. * @param scanlineStride The line stride of the image data. * @param bandOffsets The offsets of all bands. * @throws IllegalArgumentException if {@code w} or * {@code h} is not greater than 0 * @throws IllegalArgumentException if any offset between bands is * greater than the scanline stride * @throws IllegalArgumentException if the product of * {@code pixelStride} and {@code w} is greater * than {@code scanlineStride} * @throws IllegalArgumentException if {@code pixelStride} is * less than any offset between bands * @throws IllegalArgumentException if {@code dataType} is not * one of the supported data types */ public PixelInterleavedSampleModel(int dataType, int w, int h, int pixelStride, int scanlineStride, int[] bandOffsets) { super(dataType, w, h, pixelStride, scanlineStride, bandOffsets); int minBandOff = this.bandOffsets[0]; int maxBandOff = this.bandOffsets[0]; for (int i = 1; i < this.bandOffsets.length; i++) { minBandOff = Math.min(minBandOff, this.bandOffsets[i]); maxBandOff = Math.max(maxBandOff, this.bandOffsets[i]); } maxBandOff -= minBandOff; if (maxBandOff > scanlineStride) { throw new IllegalArgumentException( "Offsets between bands must be" + " less than the scanline " + " stride"); } if (pixelStride * w > scanlineStride) { throw new IllegalArgumentException( "Pixel stride times width " + "must be less than or " + "equal to the scanline " + "stride"); } if (pixelStride < maxBandOff) { throw new IllegalArgumentException( "Pixel stride must be greater" + " than or equal to the offsets" + " between bands"); } } /** * Creates a new PixelInterleavedSampleModel with the specified * width and height. The new PixelInterleavedSampleModel will have the * same number of bands, storage data type, and pixel stride * as this PixelInterleavedSampleModel. The band offsets may be * compressed such that the minimum of all of the band offsets is zero. * @param w the width of the resulting {@code SampleModel} * @param h the height of the resulting {@code SampleModel} * @return a new {@code SampleModel} with the specified width * and height. * @throws IllegalArgumentException if {@code w} or * {@code h} is not greater than 0 */ public SampleModel createCompatibleSampleModel(int w, int h) { int minBandoff = bandOffsets[0]; int numBands = bandOffsets.length; for (int i = 1; i < numBands; i++) { if (bandOffsets[i] < minBandoff) { minBandoff = bandOffsets[i]; } } int[] bandOff; if (minBandoff > 0) { bandOff = new int[numBands]; for (int i = 0; i < numBands; i++) { bandOff[i] = bandOffsets[i] - minBandoff; } } else { bandOff = bandOffsets; } return new PixelInterleavedSampleModel(dataType, w, h, pixelStride, pixelStride * w, bandOff); } /** * Creates a new PixelInterleavedSampleModel with a subset of the * bands of this PixelInterleavedSampleModel. The new * PixelInterleavedSampleModel can be used with any DataBuffer that the * existing PixelInterleavedSampleModel can be used with. The new * PixelInterleavedSampleModel/DataBuffer combination will represent * an image with a subset of the bands of the original * PixelInterleavedSampleModel/DataBuffer combination. */ public SampleModel createSubsetSampleModel(int[] bands) { int[] newBandOffsets = new int[bands.length]; for (int i = 0; i < bands.length; i++) { newBandOffsets[i] = bandOffsets[bands[i]]; } return new PixelInterleavedSampleModel(this.dataType, width, height, this.pixelStride, scanlineStride, newBandOffsets); } // Differentiate hash code from other ComponentSampleModel subclasses public int hashCode() { return super.hashCode() ^ 0x1; } }