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comparison dwt/internal/image/PngDecodingDataStream.d @ 6:b903c16b6f48

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Removed throws decls
author Frank Benoit <benoit@tionex.de>
date Wed, 27 Aug 2008 14:10:03 +0200
parents 1a8b3cb347e0
children e831403a80a9
comparison
equal deleted inserted replaced
5:1a8b3cb347e0 6:b903c16b6f48
25 int adlerValue; 25 int adlerValue;
26 26
27 static final int PRIME = 65521; 27 static final int PRIME = 65521;
28 static final int MAX_BIT = 7; 28 static final int MAX_BIT = 7;
29 29
30 this(InputStream stream) throws IOException { 30 this(InputStream stream) {
31 super(); 31 super();
32 this.stream = stream; 32 this.stream = stream;
33 nextBitIndex = MAX_BIT + 1; 33 nextBitIndex = MAX_BIT + 1;
34 adlerValue = 1; 34 adlerValue = 1;
35 lzBlockReader = new PngLzBlockReader(this); 35 lzBlockReader = new PngLzBlockReader(this);
42 * that all of the compressed image data has been read. This 42 * that all of the compressed image data has been read. This
43 * method will ensure that the next data value is an end of 43 * method will ensure that the next data value is an end of
44 * block marker. If there are more blocks after this one, 44 * block marker. If there are more blocks after this one,
45 * the method will read them and ensure that they are empty. 45 * the method will read them and ensure that they are empty.
46 */ 46 */
47 void assertImageDataAtEnd() throws IOException { 47 void assertImageDataAtEnd() {
48 lzBlockReader.assertCompressedDataAtEnd(); 48 lzBlockReader.assertCompressedDataAtEnd();
49 } 49 }
50 50
51 public void close() throws IOException { 51 public void close() {
52 assertImageDataAtEnd(); 52 assertImageDataAtEnd();
53 checkAdler(); 53 checkAdler();
54 } 54 }
55 55
56 int getNextIdatBits(int length) throws IOException { 56 int getNextIdatBits(int length) {
57 int value = 0; 57 int value = 0;
58 for (int i = 0; i < length; i++) { 58 for (int i = 0; i < length; i++) {
59 value |= (getNextIdatBit() << i); 59 value |= (getNextIdatBit() << i);
60 } 60 }
61 return value; 61 return value;
62 } 62 }
63 63
64 int getNextIdatBit() throws IOException { 64 int getNextIdatBit() {
65 if (nextBitIndex > MAX_BIT) { 65 if (nextBitIndex > MAX_BIT) {
66 currentByte = getNextIdatByte(); 66 currentByte = getNextIdatByte();
67 nextBitIndex = 0; 67 nextBitIndex = 0;
68 } 68 }
69 return (currentByte & (1 << nextBitIndex)) >> nextBitIndex++; 69 return (currentByte & (1 << nextBitIndex)) >> nextBitIndex++;
70 } 70 }
71 71
72 byte getNextIdatByte() throws IOException { 72 byte getNextIdatByte() {
73 byte nextByte = (byte)stream.read(); 73 byte nextByte = (byte)stream.read();
74 nextBitIndex = MAX_BIT + 1; 74 nextBitIndex = MAX_BIT + 1;
75 return nextByte; 75 return nextByte;
76 } 76 }
77 77
82 low = (low + valueInt) % PRIME; 82 low = (low + valueInt) % PRIME;
83 high = (low + high) % PRIME; 83 high = (low + high) % PRIME;
84 adlerValue = (high << 16) | low; 84 adlerValue = (high << 16) | low;
85 } 85 }
86 86
87 public int read() throws IOException { 87 public int read() {
88 byte nextDecodedByte = lzBlockReader.getNextByte(); 88 byte nextDecodedByte = lzBlockReader.getNextByte();
89 updateAdler(nextDecodedByte); 89 updateAdler(nextDecodedByte);
90 return nextDecodedByte & 0xFF; 90 return nextDecodedByte & 0xFF;
91 } 91 }
92 92
93 public int read(byte[] buffer, int off, int len) throws IOException { 93 public int read(byte[] buffer, int off, int len) {
94 for (int i = 0; i < len; i++) { 94 for (int i = 0; i < len; i++) {
95 int b = read(); 95 int b = read();
96 if (b is -1) return i; 96 if (b is -1) return i;
97 buffer[off + i] = (byte)b; 97 buffer[off + i] = (byte)b;
98 } 98 }
101 101
102 void error() { 102 void error() {
103 DWT.error(DWT.ERROR_INVALID_IMAGE); 103 DWT.error(DWT.ERROR_INVALID_IMAGE);
104 } 104 }
105 105
106 private void readCompressedDataHeader() throws IOException { 106 private void readCompressedDataHeader() {
107 byte headerByte1 = getNextIdatByte(); 107 byte headerByte1 = getNextIdatByte();
108 byte headerByte2 = getNextIdatByte(); 108 byte headerByte2 = getNextIdatByte();
109 109
110 int number = ((headerByte1 & 0xFF) << 8) | (headerByte2 & 0xFF); 110 int number = ((headerByte1 & 0xFF) << 8) | (headerByte2 & 0xFF);
111 if (number % 31 !is 0) error(); 111 if (number % 31 !is 0) error();
122 if (dictionary !is 0) error(); 122 if (dictionary !is 0) error();
123 123
124 // int compressionLevel = (headerByte2 & 0xC0) >> 6; 124 // int compressionLevel = (headerByte2 & 0xC0) >> 6;
125 } 125 }
126 126
127 void checkAdler() throws IOException { 127 void checkAdler() {
128 int storedAdler = ((getNextIdatByte() & 0xFF) << 24) 128 int storedAdler = ((getNextIdatByte() & 0xFF) << 24)
129 | ((getNextIdatByte() & 0xFF) << 16) 129 | ((getNextIdatByte() & 0xFF) << 16)
130 | ((getNextIdatByte() & 0xFF) << 8) 130 | ((getNextIdatByte() & 0xFF) << 8)
131 | (getNextIdatByte() & 0xFF); 131 | (getNextIdatByte() & 0xFF);
132 if (storedAdler !is adlerValue) error(); 132 if (storedAdler !is adlerValue) error();