blob: 15f47779905667cc3c3fded55d0d293be0fb0e42 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
/*******************************************************************************
* Copyright (c) 2000, 2003 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.internal.image;
import org.eclipse.swt.*;
public class PngChunkReader {
LEDataInputStream inputStream;
PngFileReadState readState;
PngIhdrChunk headerChunk;
PngPlteChunk paletteChunk;
PngChunkReader(LEDataInputStream inputStream) {
this.inputStream = inputStream;
readState = new PngFileReadState();
headerChunk = null;
}
PngIhdrChunk getIhdrChunk() {
if (headerChunk == null) {
try {
PngChunk chunk = PngChunk.readNextFromStream(inputStream);
if (chunk == null) SWT.error(SWT.ERROR_INVALID_IMAGE);
headerChunk = (PngIhdrChunk) chunk;
headerChunk.validate(readState, null);
} catch (ClassCastException e) {
SWT.error(SWT.ERROR_INVALID_IMAGE);
}
}
return headerChunk;
}
PngChunk readNextChunk() {
if (headerChunk == null) return getIhdrChunk();
PngChunk chunk = PngChunk.readNextFromStream(inputStream);
if (chunk == null) SWT.error(SWT.ERROR_INVALID_IMAGE);
switch (chunk.getChunkType()) {
case PngChunk.CHUNK_tRNS:
((PngTrnsChunk) chunk).validate(readState, headerChunk, paletteChunk);
break;
case PngChunk.CHUNK_PLTE:
chunk.validate(readState, headerChunk);
paletteChunk = (PngPlteChunk) chunk;
break;
default:
chunk.validate(readState, headerChunk);
}
if (readState.readIDAT && !(chunk.getChunkType() == PngChunk.CHUNK_IDAT)) {
readState.readPixelData = true;
}
return chunk;
}
boolean readPixelData() {
return readState.readPixelData;
}
boolean hasMoreChunks() {
return !readState.readIEND;
}
}
|
