1 /**
2 * Copyright (c) 2011, The University of Southampton and the individual contributors.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without modification,
6 * are permitted provided that the following conditions are met:
7 *
8 * * Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 *
11 * * Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * * Neither the name of the University of Southampton nor the names of its
16 * contributors may be used to endorse or promote products derived from this
17 * software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
26 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
28 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30 package org.openimaj.image.feature.dense.binarypattern;
31
32 import gnu.trove.list.array.TIntArrayList;
33
34 import org.openimaj.citation.annotation.Reference;
35 import org.openimaj.citation.annotation.ReferenceType;
36 import org.openimaj.feature.FloatFV;
37
38 /**
39 * Class for extracting histograms of Local Uniform Binary Patterns. Uniform
40 * patterns have less than one 01 transition and one 01 transition when viewed
41 * as a circular buffer.
42 *
43 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
44 */
45 @Reference(
46 type = ReferenceType.Article,
47 author = { "Ojala, T.", "Pietikainen, M.", "Maenpaa, T." },
48 title = "Multiresolution gray-scale and rotation invariant texture classification with local binary patterns",
49 year = "2002",
50 journal = "Pattern Analysis and Machine Intelligence, IEEE Transactions on",
51 pages = { "971 ", "987" },
52 month = "jul",
53 number = "7",
54 volume = "24",
55 customData = {
56 "doi", "10.1109/TPAMI.2002.1017623",
57 "ISSN", "0162-8828"
58 })
59 public class LocalUniformBinaryPatternHistogram {
60 protected int blocksize_x;
61 protected int blocksize_y;
62 FloatFV[][] histograms;
63
64 /**
65 * Construct the extractor with the given block size for each local patch.
66 *
67 * @param blocksize_x
68 * the width of the blocks
69 * @param blocksize_y
70 * the height of the blocks
71 */
72 public LocalUniformBinaryPatternHistogram(int blocksize_x, int blocksize_y) {
73 this.blocksize_x = blocksize_x;
74 this.blocksize_y = blocksize_y;
75 }
76
77 /**
78 * Compute the histograms for the given pattern image, encoded with the
79 * given number of bits.
80 *
81 * @param patternImage
82 * the pattern data
83 * @param nbits
84 * the number of bits used to encode the patterns
85 */
86 public void calculateHistograms(int[][] patternImage, int nbits) {
87 final int height = patternImage.length;
88 final int width = patternImage[0].length;
89 final TIntArrayList uniformPatterns = UniformBinaryPattern.getUniformPatterns(nbits);
90
91 histograms = new FloatFV[(int) Math.ceil((double) height / (double) blocksize_y)][(int) Math.ceil((double) width
92 / (double) blocksize_x)];
93
94 for (int y = 0, j = 0; y < height; y += blocksize_y, j++) {
95 for (int x = 0, i = 0; x < width; x += blocksize_x, i++) {
96 histograms[j][i] = new FloatFV(uniformPatterns.size() + 1);
97
98 for (int yy = y; yy < Math.min(height, y + blocksize_y); yy++) {
99 for (int xx = x; xx < Math.min(width, x + blocksize_x); xx++) {
100 final int idx = uniformPatterns.indexOf(patternImage[yy][xx]);
101
102 histograms[j][i].values[idx + 1]++;
103 }
104 }
105 }
106 }
107 }
108
109 /**
110 * Get the histograms
111 *
112 * @return the histograms
113 */
114 public FloatFV[][] getHistograms() {
115 return histograms;
116 }
117
118 /**
119 * Get the histograms as a single {@link FloatFV}.
120 *
121 * @return the histograms
122 */
123 public FloatFV getHistogram() {
124 final int len = histograms[0][0].length();
125 final FloatFV h = new FloatFV(histograms.length * histograms[0].length * len);
126
127 for (int j = 0; j < histograms.length; j++) {
128 for (int i = 0; i < histograms[0].length; i++) {
129 final int blkid = i + j * histograms[0].length;
130 System.arraycopy(histograms[j][i].values, 0, h.values, blkid * len, len);
131 }
132 }
133
134 return h;
135 }
136 }