View Javadoc
1   /*
2    * Copyright (c) 2001, 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
18   * 2 along with this work; if not, write to the Free Software Foundation,
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
23   * questions.
24   */
25  
26  package com.sun.imageio.plugins.jpeg;
27  
28  //import javax.imageio.IIOException;
29  import javax.imageio.metadata.IIOInvalidTreeException;
30  import javax.imageio.metadata.IIOMetadataNode;
31  import javax.imageio.stream.ImageOutputStream;
32  
33  import java.io.IOException;
34  
35  import org.w3c.dom.Node;
36  import org.w3c.dom.NodeList;
37  import org.w3c.dom.NamedNodeMap;
38  
39  /**
40   * An SOF (Start Of Frame)  marker segment.
41   */
42  class SOFMarkerSegment extends MarkerSegment {
43      int samplePrecision;
44      int numLines;
45      int samplesPerLine;
46      ComponentSpec [] componentSpecs;  // Array size is num components
47  
48      SOFMarkerSegment(boolean wantProg,
49                       boolean wantExtended,
50                       boolean willSubsample,
51                       byte[] componentIDs,
52                       int numComponents) {
53          super(wantProg ? JPEG.SOF2
54                : wantExtended ? JPEG.SOF1
55                : JPEG.SOF0);
56          samplePrecision = 8;
57          numLines = 0;
58          samplesPerLine = 0;
59          componentSpecs = new ComponentSpec[numComponents];
60          for(int i = 0; i < numComponents; i++) {
61              int factor = 1;
62              int qsel = 0;
63              if (willSubsample) {
64                  factor = 2;
65                  if ((i == 1) || (i == 2)) {
66                      factor = 1;
67                      qsel = 1;
68                  }
69              }
70              componentSpecs[i] = new ComponentSpec(componentIDs[i], factor, qsel);
71          }
72      }
73  
74      SOFMarkerSegment(JPEGBuffer buffer) throws IOException{
75          super(buffer);
76          samplePrecision = buffer.buf[buffer.bufPtr++];
77          numLines = (buffer.buf[buffer.bufPtr++] & 0xff) << 8;
78          numLines |= buffer.buf[buffer.bufPtr++] & 0xff;
79          samplesPerLine = (buffer.buf[buffer.bufPtr++] & 0xff) << 8;
80          samplesPerLine |= buffer.buf[buffer.bufPtr++] & 0xff;
81          int numComponents = buffer.buf[buffer.bufPtr++] & 0xff;
82          componentSpecs = new ComponentSpec [numComponents];
83          for (int i = 0; i < numComponents; i++) {
84              componentSpecs[i] = new ComponentSpec(buffer);
85          }
86          buffer.bufAvail -= length;
87      }
88  
89      SOFMarkerSegment(Node node) throws IIOInvalidTreeException {
90          // All attributes are optional, so setup defaults first
91          super(JPEG.SOF0);
92          samplePrecision = 8;
93          numLines = 0;
94          samplesPerLine = 0;
95          updateFromNativeNode(node, true);
96      }
97  
98      protected Object clone() {
99          SOFMarkerSegment newGuy = (SOFMarkerSegment) super.clone();
100         if (componentSpecs != null) {
101             newGuy.componentSpecs = (ComponentSpec []) componentSpecs.clone();
102             for (int i = 0; i < componentSpecs.length; i++) {
103                 newGuy.componentSpecs[i] =
104                     (ComponentSpec) componentSpecs[i].clone();
105             }
106         }
107         return newGuy;
108     }
109 
110     IIOMetadataNode getNativeNode() {
111         IIOMetadataNode node = new IIOMetadataNode("sof");
112         node.setAttribute("process", Integer.toString(tag-JPEG.SOF0));
113         node.setAttribute("samplePrecision",
114                           Integer.toString(samplePrecision));
115         node.setAttribute("numLines",
116                           Integer.toString(numLines));
117         node.setAttribute("samplesPerLine",
118                           Integer.toString(samplesPerLine));
119         node.setAttribute("numFrameComponents",
120                           Integer.toString(componentSpecs.length));
121         for (int i = 0; i < componentSpecs.length; i++) {
122             node.appendChild(componentSpecs[i].getNativeNode());
123         }
124 
125         return node;
126     }
127 
128     void updateFromNativeNode(Node node, boolean fromScratch)
129         throws IIOInvalidTreeException {
130         NamedNodeMap attrs = node.getAttributes();
131         int value = getAttributeValue(node, attrs, "process", 0, 2, false);
132         tag = (value != -1) ? value+JPEG.SOF0 : tag;
133         // If samplePrecision is present, it must be 8.
134         // This just checks.  We don't bother to assign the value.
135         value = getAttributeValue(node, attrs, "samplePrecision", 8, 8, false);
136         value = getAttributeValue(node, attrs, "numLines", 0, 65535, false);
137         numLines = (value != -1) ? value : numLines;
138         value = getAttributeValue(node, attrs, "samplesPerLine", 0, 65535, false);
139         samplesPerLine = (value != -1) ? value : samplesPerLine;
140         int numComponents = getAttributeValue(node, attrs, "numFrameComponents",
141                                               1, 4, false);
142         NodeList children = node.getChildNodes();
143         if (children.getLength() != numComponents) {
144             throw new IIOInvalidTreeException
145                 ("numFrameComponents must match number of children", node);
146         }
147         componentSpecs = new ComponentSpec [numComponents];
148         for (int i = 0; i < numComponents; i++) {
149             componentSpecs[i] = new ComponentSpec(children.item(i));
150         }
151     }
152 
153     /**
154      * Writes the data for this segment to the stream in
155      * valid JPEG format.
156      */
157     void write(ImageOutputStream ios) throws IOException {
158         // We don't write SOF segments; the IJG library does.
159     }
160 
161     void print () {
162         printTag("SOF");
163         System.out.print("Sample precision: ");
164         System.out.println(samplePrecision);
165         System.out.print("Number of lines: ");
166         System.out.println(numLines);
167         System.out.print("Samples per line: ");
168         System.out.println(samplesPerLine);
169         System.out.print("Number of components: ");
170         System.out.println(componentSpecs.length);
171         for(int i = 0; i<componentSpecs.length; i++) {
172             componentSpecs[i].print();
173         }
174     }
175 
176     int getIDencodedCSType () {
177         for (int i = 0; i < componentSpecs.length; i++) {
178             if (componentSpecs[i].componentId < 'A') {
179                 return JPEG.JCS_UNKNOWN;
180             }
181         }
182         switch(componentSpecs.length) {
183         case 3:
184             if ((componentSpecs[0].componentId == 'R')
185                 &&(componentSpecs[0].componentId == 'G')
186                 &&(componentSpecs[0].componentId == 'B')) {
187                 return JPEG.JCS_RGB;
188             }
189             if ((componentSpecs[0].componentId == 'Y')
190                 &&(componentSpecs[0].componentId == 'C')
191                 &&(componentSpecs[0].componentId == 'c')) {
192                 return JPEG.JCS_YCC;
193             }
194             break;
195         case 4:
196             if ((componentSpecs[0].componentId == 'R')
197                 &&(componentSpecs[0].componentId == 'G')
198                 &&(componentSpecs[0].componentId == 'B')
199                 &&(componentSpecs[0].componentId == 'A')) {
200                 return JPEG.JCS_RGBA;
201             }
202             if ((componentSpecs[0].componentId == 'Y')
203                 &&(componentSpecs[0].componentId == 'C')
204                 &&(componentSpecs[0].componentId == 'c')
205                 &&(componentSpecs[0].componentId == 'A')) {
206                 return JPEG.JCS_YCCA;
207             }
208         }
209 
210         return JPEG.JCS_UNKNOWN;
211     }
212 
213     ComponentSpec getComponentSpec(byte id, int factor, int qSelector) {
214         return new ComponentSpec(id, factor, qSelector);
215     }
216 
217     /**
218      * A component spec within an SOF marker segment.
219      */
220     class ComponentSpec implements Cloneable {
221         int componentId;
222         int HsamplingFactor;
223         int VsamplingFactor;
224         int QtableSelector;
225 
226         ComponentSpec(byte id, int factor, int qSelector) {
227             componentId = id;
228             HsamplingFactor = factor;
229             VsamplingFactor = factor;
230             QtableSelector = qSelector;
231         }
232 
233         ComponentSpec(JPEGBuffer buffer) {
234             // Parent already did a loadBuf
235             componentId = buffer.buf[buffer.bufPtr++];
236             HsamplingFactor = buffer.buf[buffer.bufPtr] >>> 4;
237             VsamplingFactor = buffer.buf[buffer.bufPtr++] & 0xf;
238             QtableSelector = buffer.buf[buffer.bufPtr++];
239         }
240 
241         ComponentSpec(Node node) throws IIOInvalidTreeException {
242             NamedNodeMap attrs = node.getAttributes();
243             componentId = getAttributeValue(node, attrs, "componentId", 0, 255, true);
244             HsamplingFactor = getAttributeValue(node, attrs, "HsamplingFactor",
245                                                 1, 255, true);
246             VsamplingFactor = getAttributeValue(node, attrs, "VsamplingFactor",
247                                                 1, 255, true);
248             QtableSelector = getAttributeValue(node, attrs, "QtableSelector",
249                                                0, 3, true);
250         }
251 
252         protected Object clone() {
253             try {
254                 return super.clone();
255             } catch (CloneNotSupportedException e) {} // won't happen
256             return null;
257         }
258 
259         IIOMetadataNode getNativeNode() {
260             IIOMetadataNode node = new IIOMetadataNode("componentSpec");
261             node.setAttribute("componentId",
262                               Integer.toString(componentId));
263             node.setAttribute("HsamplingFactor",
264                               Integer.toString(HsamplingFactor));
265             node.setAttribute("VsamplingFactor",
266                               Integer.toString(VsamplingFactor));
267             node.setAttribute("QtableSelector",
268                               Integer.toString(QtableSelector));
269             return node;
270         }
271 
272         void print () {
273             System.out.print("Component ID: ");
274             System.out.println(componentId);
275             System.out.print("H sampling factor: ");
276             System.out.println(HsamplingFactor);
277             System.out.print("V sampling factor: ");
278             System.out.println(VsamplingFactor);
279             System.out.print("Q table selector: ");
280             System.out.println(QtableSelector);
281         }
282     }
283 
284 }