Mercurial > projects > dwt2

annotate org.eclipse.swt.win32.win32.x86/src/org/eclipse/swt/internal/image/PngTrnsChunk.d @ 0:6dd524f61e62

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
add dwt win and basic java stuff
author Frank Benoit <benoit@tionex.de>
date Mon, 02 Mar 2009 14:44:16 +0100
parents
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
1 /*******************************************************************************
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
2 * Copyright (c) 2000, 2006 IBM Corporation and others.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
3 * All rights reserved. This program and the accompanying materials
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
4 * are made available under the terms of the Eclipse Public License v1.0
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
5 * which accompanies this distribution, and is available at
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
6 * http://www.eclipse.org/legal/epl-v10.html
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
7 *
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
8 * Contributors:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
9 * IBM Corporation - initial API and implementation
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
10 * Port to the D programming language:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
11 * Frank Benoit <benoit@tionex.de>
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
12 *******************************************************************************/
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
13 module org.eclipse.swt.internal.image.PngTrnsChunk;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
14
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
15 import org.eclipse.swt.SWT;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
16 import org.eclipse.swt.graphics.PaletteData;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
17 import org.eclipse.swt.graphics.RGB;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
18 import org.eclipse.swt.internal.image.PngChunk;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
19 import org.eclipse.swt.internal.image.PNGFileFormat;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
20 import org.eclipse.swt.internal.image.PngFileReadState;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
21 import org.eclipse.swt.internal.image.PngIhdrChunk;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
22 import org.eclipse.swt.internal.image.PngPlteChunk;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
23
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
24 public class PngTrnsChunk : PngChunk {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
25
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
26 alias PngChunk.validate validate;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
27
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
28 static const int TRANSPARENCY_TYPE_PIXEL = 0;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
29 static const int TRANSPARENCY_TYPE_ALPHAS = 1;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
30 static const int RGB_DATA_LENGTH = 6;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
31
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
32 this(RGB rgb) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
33 super(RGB_DATA_LENGTH);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
34 setType(TYPE_tRNS);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
35 setInt16(DATA_OFFSET, rgb.red);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
36 setInt16(DATA_OFFSET + 2, rgb.green);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
37 setInt16(DATA_OFFSET + 4, rgb.blue);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
38 setCRC(computeCRC());
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
39 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
40
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
41 this(byte[] reference){
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
42 super(reference);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
43 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
44
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
45 override int getChunkType() {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
46 return CHUNK_tRNS;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
47 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
48
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
49 void validateLength(PngIhdrChunk header, PngPlteChunk paletteChunk) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
50 bool valid;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
51 switch (header.getColorType()) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
52 case PngIhdrChunk.COLOR_TYPE_RGB:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
53 // Three 2-byte values (RGB)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
54 valid = getLength() is 6;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
55 break;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
56 case PngIhdrChunk.COLOR_TYPE_PALETTE:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
57 // Three 2-byte values (RGB)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
58 valid = getLength() <= paletteChunk.getLength();
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
59 break;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
60 case PngIhdrChunk.COLOR_TYPE_GRAYSCALE:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
61 // One 2-byte value
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
62 valid = getLength() is 2;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
63 break;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
64 // Cannot use both Alpha and tRNS
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
65 case PngIhdrChunk.COLOR_TYPE_RGB_WITH_ALPHA:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
66 case PngIhdrChunk.COLOR_TYPE_GRAYSCALE_WITH_ALPHA:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
67 default:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
68 valid = false;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
69 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
70 if (!valid) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
71 SWT.error(SWT.ERROR_INVALID_IMAGE);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
72 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
73 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
74
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
75 /**
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
76 * Answer whether the chunk is a valid tRNS chunk.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
77 */
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
78 void validate(PngFileReadState readState, PngIhdrChunk headerChunk, PngPlteChunk paletteChunk) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
79 if (!readState.readIHDR
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
80 || (headerChunk.getMustHavePalette() && !readState.readPLTE)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
81 || readState.readIDAT
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
82 || readState.readIEND)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
83 {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
84 SWT.error(SWT.ERROR_INVALID_IMAGE);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
85 } else {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
86 readState.readTRNS = true;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
87 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
88
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
89 validateLength(headerChunk, paletteChunk);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
90
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
91 super.validate(readState, headerChunk);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
92 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
93
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
94
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
95 int getTransparencyType(PngIhdrChunk header) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
96 if (header.getColorType() is PngIhdrChunk.COLOR_TYPE_PALETTE) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
97 return TRANSPARENCY_TYPE_ALPHAS;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
98 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
99 return TRANSPARENCY_TYPE_PIXEL;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
100 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
101
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
102 /**
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
103 * Answer the transparent pixel RGB value.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
104 * This is not valid for palette color types.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
105 * This is not valid for alpha color types.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
106 * This will convert a grayscale value into
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
107 * a palette index.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
108 * It will compress a 6 byte RGB into a 3 byte
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
109 * RGB.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
110 */
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
111 int getSwtTransparentPixel(PngIhdrChunk header) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
112 switch (header.getColorType()) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
113 case PngIhdrChunk.COLOR_TYPE_GRAYSCALE:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
114 int gray = ((reference[DATA_OFFSET] & 0xFF) << 8)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
115 + (reference[DATA_OFFSET + 1] & 0xFF);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
116 if (header.getBitDepth() > 8) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
117 return PNGFileFormat.compress16BitDepthTo8BitDepth(gray);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
118 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
119 return gray & 0xFF;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
120 case PngIhdrChunk.COLOR_TYPE_RGB:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
121 int red = ((reference[DATA_OFFSET] & 0xFF) << 8)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
122 | (reference[DATA_OFFSET + 1] & 0xFF);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
123 int green = ((reference[DATA_OFFSET + 2] & 0xFF) << 8)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
124 | (reference[DATA_OFFSET + 3] & 0xFF);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
125 int blue = ((reference[DATA_OFFSET + 4] & 0xFF) << 8)
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
126 | (reference[DATA_OFFSET + 5] & 0xFF);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
127 if (header.getBitDepth() > 8) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
128 red = PNGFileFormat.compress16BitDepthTo8BitDepth(red);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
129 green = PNGFileFormat.compress16BitDepthTo8BitDepth(green);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
130 blue = PNGFileFormat.compress16BitDepthTo8BitDepth(blue);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
131 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
132 return (red << 16) | (green << 8) | blue;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
133 default:
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
134 SWT.error(SWT.ERROR_INVALID_IMAGE);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
135 return -1;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
136 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
137 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
138
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
139 /**
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
140 * Answer an array of Alpha values that correspond to the
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
141 * colors in the palette.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
142 * This is only valid for the COLOR_TYPE_PALETTE color type.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
143 */
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
144 byte[] getAlphaValues(PngIhdrChunk header, PngPlteChunk paletteChunk) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
145 if (header.getColorType() !is PngIhdrChunk.COLOR_TYPE_PALETTE) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
146 SWT.error(SWT.ERROR_INVALID_IMAGE);
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
147 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
148 byte[] alphas = new byte[paletteChunk.getPaletteSize()];
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
149 int dataLength = getLength();
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
150 int i = 0;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
151 for (i = 0; i < dataLength; i++) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
152 alphas[i] = reference[DATA_OFFSET + i];
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
153 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
154 /**
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
155 * Any palette entries which do not have a corresponding
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
156 * alpha value in the tRNS chunk are spec'd to have an
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
157 * alpha of 255.
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
158 */
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
159 for (int j = i; j < alphas.length; j++) {
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
160 alphas[j] = cast(byte) 255;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
161 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
162 return alphas;
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
163 }
6dd524f61e62 add dwt win and basic java stuff
Frank Benoit <benoit@tionex.de>
parents:
diff changeset
164 }