1 /*
2 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
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24 */
25
26 package java.awt.image;
27
28 /**
29 * This class represents image data which is stored in a pixel interleaved
30 * fashion and for
31 * which each sample of a pixel occupies one data element of the DataBuffer.
32 * It subclasses ComponentSampleModel but provides a more efficient
33 * implementation for accessing pixel interleaved image data than is provided
34 * by ComponentSampleModel. This class
35 * stores sample data for all bands in a single bank of the
36 * DataBuffer. Accessor methods are provided so that image data can be
37 * manipulated directly. Pixel stride is the number of
38 * data array elements between two samples for the same band on the same
39 * scanline. Scanline stride is the number of data array elements between
40 * a given sample and the corresponding sample in the same column of the next
41 * scanline. Band offsets denote the number
42 * of data array elements from the first data array element of the bank
43 * of the DataBuffer holding each band to the first sample of the band.
44 * The bands are numbered from 0 to N-1.
45 * Bank indices denote the correspondence between a bank of the data buffer
46 * and a band of image data.
47 * This class supports
48 * {@link DataBuffer#TYPE_BYTE TYPE_BYTE},
49 * {@link DataBuffer#TYPE_USHORT TYPE_USHORT},
50 * {@link DataBuffer#TYPE_SHORT TYPE_SHORT},
51 * {@link DataBuffer#TYPE_INT TYPE_INT},
52 * {@link DataBuffer#TYPE_FLOAT TYPE_FLOAT} and
53 * {@link DataBuffer#TYPE_DOUBLE TYPE_DOUBLE} datatypes.
54 */
55
56 public class PixelInterleavedSampleModel extends ComponentSampleModel
57 {
58 /**
59 * Constructs a PixelInterleavedSampleModel with the specified parameters.
60 * The number of bands will be given by the length of the bandOffsets
61 * array.
62 * @param dataType The data type for storing samples.
63 * @param w The width (in pixels) of the region of
64 * image data described.
65 * @param h The height (in pixels) of the region of
66 * image data described.
67 * @param pixelStride The pixel stride of the image data.
68 * @param scanlineStride The line stride of the image data.
69 * @param bandOffsets The offsets of all bands.
70 * @throws IllegalArgumentException if {@code w} or
71 * {@code h} is not greater than 0
72 * @throws IllegalArgumentException if any offset between bands is
73 * greater than the scanline stride
74 * @throws IllegalArgumentException if the product of
75 * {@code pixelStride} and {@code w} is greater
76 * than {@code scanlineStride}
77 * @throws IllegalArgumentException if {@code pixelStride} is
78 * less than any offset between bands
79 * @throws IllegalArgumentException if {@code dataType} is not
80 * one of the supported data types
81 */
82 public PixelInterleavedSampleModel(int dataType,
83 int w, int h,
84 int pixelStride,
85 int scanlineStride,
86 int bandOffsets[]) {
87 super(dataType, w, h, pixelStride, scanlineStride, bandOffsets);
88 int minBandOff=this.bandOffsets[0];
89 int maxBandOff=this.bandOffsets[0];
90 for (int i=1; i<this.bandOffsets.length; i++) {
91 minBandOff = Math.min(minBandOff,this.bandOffsets[i]);
92 maxBandOff = Math.max(maxBandOff,this.bandOffsets[i]);
93 }
94 maxBandOff -= minBandOff;
95 if (maxBandOff > scanlineStride) {
96 throw new IllegalArgumentException("Offsets between bands must be"+
97 " less than the scanline "+
98 " stride");
99 }
100 if (pixelStride*w > scanlineStride) {
101 throw new IllegalArgumentException("Pixel stride times width "+
102 "must be less than or "+
103 "equal to the scanline "+
104 "stride");
105 }
106 if (pixelStride < maxBandOff) {
107 throw new IllegalArgumentException("Pixel stride must be greater"+
108 " than or equal to the offsets"+
109 " between bands");
110 }
111 }
112
113 /**
114 * Creates a new PixelInterleavedSampleModel with the specified
115 * width and height. The new PixelInterleavedSampleModel will have the
116 * same number of bands, storage data type, and pixel stride
117 * as this PixelInterleavedSampleModel. The band offsets may be
118 * compressed such that the minimum of all of the band offsets is zero.
119 * @param w the width of the resulting {@code SampleModel}
120 * @param h the height of the resulting {@code SampleModel}
121 * @return a new {@code SampleModel} with the specified width
122 * and height.
123 * @throws IllegalArgumentException if {@code w} or
124 * {@code h} is not greater than 0
125 */
126 public SampleModel createCompatibleSampleModel(int w, int h) {
127 int minBandoff=bandOffsets[0];
128 int numBands = bandOffsets.length;
129 for (int i=1; i < numBands; i++) {
130 if (bandOffsets[i] < minBandoff) {
131 minBandoff = bandOffsets[i];
132 }
133 }
134 int[] bandOff;
135 if (minBandoff > 0) {
136 bandOff = new int[numBands];
137 for (int i=0; i < numBands; i++) {
138 bandOff[i] = bandOffsets[i] - minBandoff;
139 }
140 }
141 else {
142 bandOff = bandOffsets;
143 }
144 return new PixelInterleavedSampleModel(dataType, w, h, pixelStride,
145 pixelStride*w, bandOff);
146 }
147
148 /**
149 * Creates a new PixelInterleavedSampleModel with a subset of the
150 * bands of this PixelInterleavedSampleModel. The new
151 * PixelInterleavedSampleModel can be used with any DataBuffer that the
152 * existing PixelInterleavedSampleModel can be used with. The new
153 * PixelInterleavedSampleModel/DataBuffer combination will represent
154 * an image with a subset of the bands of the original
155 * PixelInterleavedSampleModel/DataBuffer combination.
156 */
157 public SampleModel createSubsetSampleModel(int bands[]) {
158 int newBandOffsets[] = new int[bands.length];
159 for (int i=0; i<bands.length; i++) {
160 newBandOffsets[i] = bandOffsets[bands[i]];
161 }
162 return new PixelInterleavedSampleModel(this.dataType, width, height,
163 this.pixelStride,
164 scanlineStride, newBandOffsets);
165 }
166
167 // Differentiate hash code from other ComponentSampleModel subclasses
168 public int hashCode() {
169 return super.hashCode() ^ 0x1;
170 }
171 }
172