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11 package org.eclipse.swt.internal.image;
12
13
14 import org.eclipse.swt.*;
15
16 final class JPEGFrameHeader extends JPEGVariableSizeSegment {
17 int maxVFactor;
18 int maxHFactor;
19 public int[] componentIdentifiers;
20 public int[][] componentParameters;
21
22 public JPEGFrameHeader(byte[] reference) {
23 super(reference);
24 }
25
26 public JPEGFrameHeader(LEDataInputStream byteStream) {
27 super(byteStream);
28 initializeComponentParameters();
29 }
30
31 public int getSamplePrecision() {
32 return reference[4] & 0xFF;
33 }
34
35 public int getNumberOfLines() {
36 return (reference[5] & 0xFF) << 8 | (reference[6] & 0xFF);
37 }
38
39 public int getSamplesPerLine() {
40 return (reference[7] & 0xFF) << 8 | (reference[8] & 0xFF);
41 }
42
43 public int getNumberOfImageComponents() {
44 return reference[9] & 0xFF;
45 }
46
47 public void setSamplePrecision(int precision) {
48 reference[4] = (byte)(precision & 0xFF);
49 }
50
51 public void setNumberOfLines(int anInteger) {
52 reference[5] = (byte)((anInteger & 0xFF00) >> 8);
53 reference[6] = (byte)(anInteger & 0xFF);
54 }
55
56 public void setSamplesPerLine(int samples) {
57 reference[7] = (byte)((samples & 0xFF00) >> 8);
58 reference[8] = (byte)(samples & 0xFF);
59 }
60
61 public void setNumberOfImageComponents(int anInteger) {
62 reference[9] = (byte)(anInteger & 0xFF);
63 }
64
65 public int getMaxHFactor() {
66 return maxHFactor;
67 }
68
69 public int getMaxVFactor() {
70 return maxVFactor;
71 }
72
73 public void setMaxHFactor(int anInteger) {
74 maxHFactor = anInteger;
75 }
76
77 public void setMaxVFactor(int anInteger) {
78 maxVFactor = anInteger;
79 }
80
81
82 void initializeComponentParameters() {
83 int nf = getNumberOfImageComponents();
84 componentIdentifiers = new int[nf];
85 int[][] compSpecParams = new int[0][];
86 int hmax = 1;
87 int vmax = 1;
88 for (int i = 0; i < nf; i++) {
89 int ofs = i * 3 + 10;
90 int ci = reference[ofs] & 0xFF;
91 componentIdentifiers[i] = ci;
92 int hi = (reference[ofs + 1] & 0xFF) >> 4;
93 int vi = reference[ofs + 1] & 0xF;
94 int tqi = reference[ofs + 2] & 0xFF;
95 if (hi > hmax) {
96 hmax = hi;
97 }
98 if (vi > vmax) {
99 vmax = vi;
100 }
101 int[] compParam = new int[5];
102 compParam[0] = tqi;
103 compParam[1] = hi;
104 compParam[2] = vi;
105 if (compSpecParams.length <= ci) {
106 int[][] newParams = new int[ci + 1][];
107 System.arraycopy(compSpecParams, 0, newParams, 0, compSpecParams.length);
108 compSpecParams = newParams;
109 }
110 compSpecParams[ci] = compParam;
111 }
112 int x = getSamplesPerLine();
113 int y = getNumberOfLines();
114 int[] multiples = new int[] { 8, 16, 24, 32 };
115 for (int i = 0; i < nf; i++) {
116 int[] compParam = compSpecParams[componentIdentifiers[i]];
117 int hi = compParam[1];
118 int vi = compParam[2];
119 int compWidth = (x * hi + hmax - 1) / hmax;
120 int compHeight = (y * vi + vmax - 1) / vmax;
121 int dsWidth = roundUpToMultiple(compWidth, multiples[hi - 1]);
122 int dsHeight = roundUpToMultiple(compHeight, multiples[vi - 1]);
123 compParam[3] = dsWidth;
124 compParam[4] = dsHeight;
125 }
126 setMaxHFactor(hmax);
127 setMaxVFactor(vmax);
128 componentParameters = compSpecParams;
129 }
130
131
132 public void initializeContents() {
133 int nf = getNumberOfImageComponents();
134 if (nf == 0 || nf != componentParameters.length) {
135 SWT.error(SWT.ERROR_INVALID_IMAGE);
136 }
137 int hmax = 0;
138 int vmax = 0;
139 int[][] compSpecParams = componentParameters;
140 for (int i = 0; i < nf; i++) {
141 int ofs = i * 3 + 10;
142 int[] compParam = compSpecParams[componentIdentifiers[i]];
143 int hi = compParam[1];
144 int vi = compParam[2];
145 if (hi * vi > 4) {
146 SWT.error(SWT.ERROR_INVALID_IMAGE);
147 }
148 reference[ofs] = (byte)(i + 1);
149 reference[ofs + 1] = (byte)(hi * 16 + vi);
150 reference[ofs + 2] = (byte)(compParam[0]);
151 if (hi > hmax) hmax = hi;
152 if (vi > vmax) vmax = vi;
153 }
154 int x = getSamplesPerLine();
155 int y = getNumberOfLines();
156 int[] multiples = new int[] {8, 16, 24, 32};
157 for (int i = 0; i < nf; i++) {
158 int[] compParam = compSpecParams[componentIdentifiers[i]];
159 int hi = compParam[1];
160 int vi = compParam[2];
161 int compWidth = (x * hi + hmax - 1) / hmax;
162 int compHeight = (y * vi + vmax - 1) / vmax;
163 int dsWidth = roundUpToMultiple(compWidth, multiples[hi - 1]);
164 int dsHeight = roundUpToMultiple(compHeight, multiples[vi - 1]);
165 compParam[3] = dsWidth;
166 compParam[4] = dsHeight;
167 }
168 setMaxHFactor(hmax);
169 setMaxVFactor(vmax);
170 }
171
172 int roundUpToMultiple(int anInteger, int mInteger) {
173 int a = anInteger + mInteger - 1;
174 return a - (a % mInteger);
175 }
176
177
195 public boolean verify() {
196 int marker = getSegmentMarker();
197 return (marker >= JPEGFileFormat.SOF0 && marker <= JPEGFileFormat.SOF3) ||
198 (marker >= JPEGFileFormat.SOF5 && marker <= JPEGFileFormat.SOF7) ||
199 (marker >= JPEGFileFormat.SOF9 && marker <= JPEGFileFormat.SOF11) ||
200 (marker >= JPEGFileFormat.SOF13 && marker <= JPEGFileFormat.SOF15);
201 }
202
203 public boolean isProgressive() {
204 int marker = getSegmentMarker();
205 return marker == JPEGFileFormat.SOF2
206 || marker == JPEGFileFormat.SOF6
207 || marker == JPEGFileFormat.SOF10
208 || marker == JPEGFileFormat.SOF14;
209 }
210
211 public boolean isArithmeticCoding() {
212 return getSegmentMarker() >= JPEGFileFormat.SOF9;
213 }
214 }
215 |
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