package org.eclipse.swt.internal.image; | |
/* | |
* (c) Copyright IBM Corp. 2000, 2001. | |
* All Rights Reserved | |
*/ | |
final class JPEGQuantizationTable extends JPEGVariableSizeSegment { | |
public static byte[] DefaultLuminanceQTable = { | |
(byte)255, (byte)219, 0, 67, 0, | |
16, 11, 10, 16, 24, 40, 51, 61, | |
12, 12, 14, 19, 26, 58, 60, 55, | |
14, 13, 16, 24, 40, 57, 69, 56, | |
14, 17, 22, 29, 51, 87, 80, 62, | |
18, 22, 37, 56, 68, 109, 103, 77, | |
24, 35, 55, 64, 81, 104, 113, 92, | |
49, 64, 78, 87, 103, 121, 120, 101, | |
72, 92, 95, 98, 112, 100, 103, 99 | |
}; | |
public static byte[] DefaultChrominanceQTable = { | |
(byte)255, (byte)219, 0, 67, 1, | |
17, 18, 24, 47, 99, 99, 99, 99, | |
18, 21, 26, 66, 99, 99, 99, 99, | |
24, 26, 56, 99, 99, 99, 99, 99, | |
47, 66, 99, 99, 99, 99, 99, 99, | |
99, 99, 99, 99, 99, 99, 99, 99, | |
99, 99, 99, 99, 99, 99, 99, 99, | |
99, 99, 99, 99, 99, 99, 99, 99, | |
99, 99, 99, 99, 99, 99, 99, 99 | |
}; | |
public JPEGQuantizationTable(byte[] reference) { | |
super(reference); | |
} | |
public JPEGQuantizationTable(LEDataInputStream byteStream) { | |
super(byteStream); | |
} | |
public static JPEGQuantizationTable defaultChrominanceTable() { | |
byte[] data = new byte[DefaultChrominanceQTable.length]; | |
System.arraycopy(DefaultChrominanceQTable, 0, data, 0, data.length); | |
return new JPEGQuantizationTable(data); | |
} | |
public static JPEGQuantizationTable defaultLuminanceTable() { | |
byte[] data = new byte[DefaultLuminanceQTable.length]; | |
System.arraycopy(DefaultLuminanceQTable, 0, data, 0, data.length); | |
return new JPEGQuantizationTable(data); | |
} | |
public int[] getQuantizationTablesKeys() { | |
int[] keys = new int[4]; | |
int keysIndex = 0; | |
int totalLength = getSegmentLength() - 2; | |
int ofs = 4; | |
while (totalLength > 64) { | |
int tq = (reference[ofs] & 0xFF) % 16; | |
int pq = (reference[ofs] & 0xFF) / 16; | |
if (pq == 0) { | |
ofs += 65; | |
totalLength -= 65; | |
} else { | |
ofs += 129; | |
totalLength -= 129; | |
} | |
if (keysIndex >= keys.length) { | |
int[] newKeys = new int[keys.length + 4]; | |
System.arraycopy(keys, 0, newKeys, 0, keys.length); | |
keys = newKeys; | |
} | |
keys[keysIndex] = tq; | |
keysIndex++; | |
} | |
int[] newKeys = new int[keysIndex]; | |
System.arraycopy(keys, 0, newKeys, 0, keysIndex); | |
return newKeys; | |
} | |
public int[][] getQuantizationTablesValues() { | |
int[][] values = new int[4][]; | |
int valuesIndex = 0; | |
int totalLength = getSegmentLength() - 2; | |
int ofs = 4; | |
while (totalLength > 64) { | |
int[] qk = new int[64]; | |
int pq = (reference[ofs] & 0xFF) / 16; | |
if (pq == 0) { | |
for (int i = 0; i < qk.length; i++) { | |
qk[i] = reference[ofs + i + 1]; | |
} | |
ofs += 65; | |
totalLength -= 65; | |
} else { | |
for (int i = 0; i < qk.length; i++) { | |
int idx = (i - 1) * 2 ; | |
qk[i] = (reference[ofs + idx + 1] & 0xFF) * 256 + (reference[ofs + idx + 2] & 0xFF); | |
} | |
ofs += 129; | |
totalLength -= 129; | |
} | |
if (valuesIndex >= values.length) { | |
int[][] newValues = new int[values.length + 4][]; | |
System.arraycopy(values, 0, newValues, 0, values.length); | |
values = newValues; | |
} | |
values[valuesIndex] = qk; | |
valuesIndex++; | |
} | |
int[][] newValues = new int[valuesIndex][]; | |
System.arraycopy(values, 0, newValues, 0, valuesIndex); | |
return newValues; | |
} | |
public void scaleBy(int qualityFactor) { | |
int qFactor = qualityFactor; | |
if (qFactor <= 0) { | |
qFactor = 1; | |
} | |
if (qFactor > 100) { | |
qFactor = 100; | |
} | |
if (qFactor < 50) { | |
qFactor = 5000 / qFactor; | |
} else { | |
qFactor = 200 - (qFactor * 2); | |
} | |
int totalLength = getSegmentLength() - 2; | |
int ofs = 4; | |
while (totalLength > 64) { | |
int tq = (reference[ofs] & 0xFF) % 16; | |
int pq = (reference[ofs] & 0xFF) / 16; | |
if (pq == 0) { | |
for (int i = ofs + 1; i <= ofs + 64; i++) { | |
int temp = ((reference[i] & 0xFF) * qFactor + 50) / 100; | |
if (temp <= 0) temp = 1; | |
if (temp > 255) temp = 255; | |
reference[i] = (byte)temp; | |
} | |
ofs += 65; | |
totalLength -= 65; | |
} else { | |
for (int i = ofs + 1; i <= ofs + 128; i += 2) { | |
int temp = (((reference[i] & 0xFF) * 256 + (reference[i + 1] & 0xFF)) * qFactor + 50) / 100; | |
if (temp <= 0) temp = 1; | |
if (temp > 32767) temp = 32767; | |
reference[i] = (byte)(temp / 256); | |
reference[i + 1] = (byte)(temp % 256); | |
} | |
ofs += 129; | |
totalLength -= 129; | |
} | |
} | |
} | |
public int signature() { | |
return JPEGFileFormat.DQT; | |
} | |
} |