diff --git a/src/main/java/cz/it4i/qcmp/cli/functions/DebugFunction.java b/src/main/java/cz/it4i/qcmp/cli/functions/DebugFunction.java
index b2a325e6395ce7004d5d7274eea951870376fc73..ca4dcf7f96406227f58c3a41f7d924d0997be12c 100644
--- a/src/main/java/cz/it4i/qcmp/cli/functions/DebugFunction.java
+++ b/src/main/java/cz/it4i/qcmp/cli/functions/DebugFunction.java
@@ -4,8 +4,8 @@ import cz.it4i.qcmp.cache.QuantizationCacheManager;
import cz.it4i.qcmp.cache.VQCacheFile;
import cz.it4i.qcmp.cli.CompressionOptionsCLIParser;
import cz.it4i.qcmp.cli.CustomFunctionBase;
-import cz.it4i.qcmp.huffman.Huffman;
import cz.it4i.qcmp.huffman.HuffmanNode;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InBitStream;
import cz.it4i.qcmp.io.OutBitStream;
import cz.it4i.qcmp.quantization.vector.VQCodebook;
@@ -36,14 +36,14 @@ public class DebugFunction extends CustomFunctionBase {
symbols[i] = i;
}
- final Huffman huffman = new Huffman(symbols, codebook.getVectorFrequencies());
+ final HuffmanTreeBuilder huffman = new HuffmanTreeBuilder(symbols, codebook.getVectorFrequencies());
huffman.buildHuffmanTree();
final int bitsPerSymbol = (int) Utils.log2(codebook.getCodebookSize());
try (final OutBitStream bitStream = new OutBitStream(new FileOutputStream("D:\\tmp\\huffman_tree.data", false),
bitsPerSymbol,
64)) {
- huffman.saveHuffmanTree(bitStream);
+ huffman.getRoot().writeToBinaryStream(bitStream);
} catch (final IOException e) {
e.printStackTrace();
}
@@ -51,7 +51,7 @@ public class DebugFunction extends CustomFunctionBase {
HuffmanNode readRoot = null;
try (final InBitStream inBitStream = new InBitStream(new FileInputStream("D:\\tmp\\huffman_tree.data"), bitsPerSymbol, 256)) {
- readRoot = Huffman.readHuffmanTree(inBitStream);
+ readRoot = HuffmanNode.readFromStream(inBitStream);
} catch (final IOException ex) {
ex.printStackTrace();
}
diff --git a/src/main/java/cz/it4i/qcmp/compression/CompressorDecompressorBase.java b/src/main/java/cz/it4i/qcmp/compression/CompressorDecompressorBase.java
index 22b328d64310d8764bcc1b61f1cfa15909aecc02..82d9453091fcfd1024a1f3413ee5e6fd7811662f 100644
--- a/src/main/java/cz/it4i/qcmp/compression/CompressorDecompressorBase.java
+++ b/src/main/java/cz/it4i/qcmp/compression/CompressorDecompressorBase.java
@@ -3,7 +3,7 @@ package cz.it4i.qcmp.compression;
import cz.it4i.qcmp.compression.exception.ImageCompressionException;
import cz.it4i.qcmp.compression.listeners.IProgressListener;
import cz.it4i.qcmp.compression.listeners.IStatusListener;
-import cz.it4i.qcmp.huffman.Huffman;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InputData;
import cz.it4i.qcmp.io.OutBitStream;
@@ -100,8 +100,8 @@ public abstract class CompressorDecompressorBase {
return symbols;
}
- protected Huffman createHuffmanCoder(final int[] symbols, final long[] frequencies) {
- final Huffman huffman = new Huffman(symbols, frequencies);
+ protected HuffmanTreeBuilder createHuffmanCoder(final int[] symbols, final long[] frequencies) {
+ final HuffmanTreeBuilder huffman = new HuffmanTreeBuilder(symbols, frequencies);
huffman.buildHuffmanTree();
return huffman;
}
@@ -157,7 +157,7 @@ public abstract class CompressorDecompressorBase {
* @throws ImageCompressionException when fails to write to compress stream.
*/
protected long writeHuffmanEncodedIndices(final DataOutputStream compressStream,
- final Huffman huffman,
+ final HuffmanTreeBuilder huffman,
final int[] indices) throws ImageCompressionException {
try (final OutBitStream outBitStream = new OutBitStream(compressStream, options.getBitsPerCodebookIndex(), 2048)) {
for (final int index : indices) {
diff --git a/src/main/java/cz/it4i/qcmp/compression/SQImageCompressor.java b/src/main/java/cz/it4i/qcmp/compression/SQImageCompressor.java
index ec32d2c0127f9a9564b42ce2c9456c0aecd7ed2a..1e7c1ec7b2ac5a96f07c3280a28f109c8ec0f34e 100644
--- a/src/main/java/cz/it4i/qcmp/compression/SQImageCompressor.java
+++ b/src/main/java/cz/it4i/qcmp/compression/SQImageCompressor.java
@@ -5,7 +5,7 @@ import cz.it4i.qcmp.cache.ICacheFile;
import cz.it4i.qcmp.cache.QuantizationCacheManager;
import cz.it4i.qcmp.cache.SQCacheFile;
import cz.it4i.qcmp.compression.exception.ImageCompressionException;
-import cz.it4i.qcmp.huffman.Huffman;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InputData;
import cz.it4i.qcmp.io.loader.IPlaneLoader;
import cz.it4i.qcmp.io.loader.PlaneLoaderFactory;
@@ -20,7 +20,7 @@ import java.io.IOException;
public class SQImageCompressor extends CompressorDecompressorBase implements IImageCompressor {
private ScalarQuantizer cachedQuantizer;
- private Huffman cachedHuffman;
+ private HuffmanTreeBuilder cachedHuffman;
public SQImageCompressor(final CompressionOptions options) {
super(options);
@@ -116,7 +116,7 @@ public class SQImageCompressor extends CompressorDecompressorBase implements IIm
}
ScalarQuantizer quantizer = null;
- Huffman huffman = null;
+ HuffmanTreeBuilder huffman = null;
final int[] huffmanSymbols = createHuffmanSymbols(getCodebookSize());
if (options.getCodebookType() == CompressionOptions.CodebookType.Global) {
reportStatusToListeners("Loading codebook from cache file.");
@@ -174,7 +174,7 @@ public class SQImageCompressor extends CompressorDecompressorBase implements IIm
quantizer = trainScalarQuantizerFromData(planeData);
writeCodebookToOutputStream(quantizer, compressStream);
- huffman = new Huffman(huffmanSymbols, quantizer.getCodebook().getSymbolFrequencies());
+ huffman = new HuffmanTreeBuilder(huffmanSymbols, quantizer.getCodebook().getSymbolFrequencies());
huffman.buildHuffmanTree();
}
diff --git a/src/main/java/cz/it4i/qcmp/compression/SQImageDecompressor.java b/src/main/java/cz/it4i/qcmp/compression/SQImageDecompressor.java
index 2cdfda862681de250c7cc022ef34def6c925a443..e72bfbb2baa95887536e68918ca3633bb681169c 100644
--- a/src/main/java/cz/it4i/qcmp/compression/SQImageDecompressor.java
+++ b/src/main/java/cz/it4i/qcmp/compression/SQImageDecompressor.java
@@ -4,8 +4,8 @@ import cz.it4i.qcmp.cache.ICacheFile;
import cz.it4i.qcmp.cache.SQCacheFile;
import cz.it4i.qcmp.compression.exception.ImageDecompressionException;
import cz.it4i.qcmp.fileformat.QCMPFileHeader;
-import cz.it4i.qcmp.huffman.Huffman;
import cz.it4i.qcmp.huffman.HuffmanNode;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InBitStream;
import cz.it4i.qcmp.quantization.scalar.SQCodebook;
import cz.it4i.qcmp.utilities.Stopwatch;
@@ -17,7 +17,7 @@ import java.io.IOException;
public class SQImageDecompressor extends CompressorDecompressorBase implements IImageDecompressor {
private SQCodebook cachedCodebook = null;
- private Huffman cachedHuffman = null;
+ private HuffmanTreeBuilder cachedHuffman = null;
public SQImageDecompressor(final CompressionOptions options) {
super(options);
@@ -52,7 +52,7 @@ public class SQImageDecompressor extends CompressorDecompressorBase implements I
final int planePixelCount = header.getImageSizeX() * header.getImageSizeY();
SQCodebook codebook = null;
- Huffman huffman = null;
+ HuffmanTreeBuilder huffman = null;
if (!header.isCodebookPerPlane()) {
// There is only one codebook.
reportStatusToListeners("Loading single codebook and huffman coder.");
@@ -130,7 +130,7 @@ public class SQImageDecompressor extends CompressorDecompressorBase implements I
final int planePixelCount = header.getImageSizeX() * header.getImageSizeY();
SQCodebook codebook = null;
- Huffman huffman = null;
+ HuffmanTreeBuilder huffman = null;
if (!header.isCodebookPerPlane()) {
// There is only one codebook.
codebook = readScalarQuantizationValues(compressedStream, codebookSize);
diff --git a/src/main/java/cz/it4i/qcmp/compression/VQImageCompressor.java b/src/main/java/cz/it4i/qcmp/compression/VQImageCompressor.java
index c64163aa97dc4d7e230aaa267ada320ecec5f035..90d3cfd7d2f1ebe8f3822ee47034e34e175bbac1 100644
--- a/src/main/java/cz/it4i/qcmp/compression/VQImageCompressor.java
+++ b/src/main/java/cz/it4i/qcmp/compression/VQImageCompressor.java
@@ -6,7 +6,7 @@ import cz.it4i.qcmp.cache.VQCacheFile;
import cz.it4i.qcmp.compression.exception.ImageCompressionException;
import cz.it4i.qcmp.data.Range;
import cz.it4i.qcmp.fileformat.QuantizationType;
-import cz.it4i.qcmp.huffman.Huffman;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InputData;
import cz.it4i.qcmp.io.loader.IPlaneLoader;
import cz.it4i.qcmp.io.loader.PlaneLoaderFactory;
@@ -24,7 +24,7 @@ import java.io.IOException;
public class VQImageCompressor extends CompressorDecompressorBase implements IImageCompressor {
private VectorQuantizer cachedQuantizer = null;
- private Huffman cachedHuffman = null;
+ private HuffmanTreeBuilder cachedHuffman = null;
private boolean useKdTree = false;
@@ -158,7 +158,7 @@ public class VQImageCompressor extends CompressorDecompressorBase implements IIm
}
VectorQuantizer quantizer = cachedQuantizer;
- Huffman huffman = cachedHuffman;
+ HuffmanTreeBuilder huffman = cachedHuffman;
assert (!streamMode || ((quantizer != null) && (huffman != null)));
if (!streamMode) {
@@ -283,7 +283,8 @@ public class VQImageCompressor extends CompressorDecompressorBase implements IIm
final long[] voxelLayersSizes = new long[voxelLayerCount];
final VectorQuantizer quantizer = (cachedQuantizer != null) ? cachedQuantizer : loadQuantizerFromCache();
- final Huffman huffman = (cachedHuffman != null) ? cachedHuffman : createHuffmanCoder(huffmanSymbols, quantizer.getFrequencies());
+ final HuffmanTreeBuilder huffman = (cachedHuffman != null) ? cachedHuffman : createHuffmanCoder(huffmanSymbols,
+ quantizer.getFrequencies());
if (!streamMode)
writeQuantizerToCompressStream(quantizer, compressStream);
diff --git a/src/main/java/cz/it4i/qcmp/compression/VQImageDecompressor.java b/src/main/java/cz/it4i/qcmp/compression/VQImageDecompressor.java
index 6be7248fdd550eee8f00f3626195c6149ec389e1..1da6828e3e2883ba57f761b676ea365929a005f4 100644
--- a/src/main/java/cz/it4i/qcmp/compression/VQImageDecompressor.java
+++ b/src/main/java/cz/it4i/qcmp/compression/VQImageDecompressor.java
@@ -6,8 +6,8 @@ import cz.it4i.qcmp.compression.exception.ImageDecompressionException;
import cz.it4i.qcmp.data.*;
import cz.it4i.qcmp.fileformat.QCMPFileHeader;
import cz.it4i.qcmp.fileformat.QuantizationType;
-import cz.it4i.qcmp.huffman.Huffman;
import cz.it4i.qcmp.huffman.HuffmanNode;
+import cz.it4i.qcmp.huffman.HuffmanTreeBuilder;
import cz.it4i.qcmp.io.InBitStream;
import cz.it4i.qcmp.quantization.vector.VQCodebook;
import cz.it4i.qcmp.utilities.Stopwatch;
@@ -20,7 +20,7 @@ import java.io.IOException;
public class VQImageDecompressor extends CompressorDecompressorBase implements IImageDecompressor {
private VQCodebook cachedCodebook = null;
- private Huffman cachedHuffman = null;
+ private HuffmanTreeBuilder cachedHuffman = null;
private interface DecompressCallback {
void process(final Block imageBlock, final int planeIndex) throws ImageDecompressionException;
@@ -90,7 +90,7 @@ public class VQImageDecompressor extends CompressorDecompressorBase implements I
}
return reconstructedChunk;
}
-
+
@Override
public void decompress(final DataInputStream compressedStream,
final DataOutputStream decompressStream,
@@ -122,7 +122,7 @@ public class VQImageDecompressor extends CompressorDecompressorBase implements I
VQCodebook codebook = null;
- Huffman huffman = null;
+ HuffmanTreeBuilder huffman = null;
if (!header.isCodebookPerPlane()) {
// There is only one codebook.
codebook = readCodebook(compressedStream, codebookSize, vectorSize);
@@ -245,7 +245,7 @@ public class VQImageDecompressor extends CompressorDecompressorBase implements I
final VQCodebook codebook = readCodebook(compressedStream, codebookSize, vectorSize);
- final Huffman huffman = createHuffmanCoder(huffmanSymbols, codebook.getVectorFrequencies());
+ final HuffmanTreeBuilder huffman = createHuffmanCoder(huffmanSymbols, codebook.getVectorFrequencies());
final int voxelLayerCount = VQImageCompressor.calculateVoxelLayerCount(header.getImageSizeZ(), header.getVectorSizeZ());
final Stopwatch stopwatch = new Stopwatch();
@@ -379,7 +379,7 @@ public class VQImageDecompressor extends CompressorDecompressorBase implements I
});
}
- private int decodeHuffmanSymbol(final Huffman huffman, final InBitStream inBitStream) throws IOException {
+ private int decodeHuffmanSymbol(final HuffmanTreeBuilder huffman, final InBitStream inBitStream) throws IOException {
HuffmanNode currentHuffmanNode = huffman.getRoot();
while (!currentHuffmanNode.isLeaf()) {
currentHuffmanNode = currentHuffmanNode.traverse(inBitStream.readBit());
diff --git a/src/main/java/cz/it4i/qcmp/huffman/HuffmanNode.java b/src/main/java/cz/it4i/qcmp/huffman/HuffmanNode.java
index f81e5d3a7c944eb06e34f96f92559c91b14fdede..4d453675f2dc69c591954f38f5ed8acd79c395e6 100644
--- a/src/main/java/cz/it4i/qcmp/huffman/HuffmanNode.java
+++ b/src/main/java/cz/it4i/qcmp/huffman/HuffmanNode.java
@@ -1,36 +1,38 @@
package cz.it4i.qcmp.huffman;
+import cz.it4i.qcmp.io.InBitStream;
+import cz.it4i.qcmp.io.OutBitStream;
import org.jetbrains.annotations.NotNull;
+import java.io.IOException;
+
public class HuffmanNode implements Comparable<HuffmanNode> {
private int symbol = -1;
- private long symbolFrequency = -1;
private int bit = -1;
private boolean leaf = false;
private double probability = 0.0;
- final HuffmanNode subNodeA;
- final HuffmanNode subNodeB;
+ final HuffmanNode rightChild;
+ final HuffmanNode leftChild;
- public HuffmanNode(final int symbol, final double probability, final long frequency) {
+ public HuffmanNode(final int symbol, final double probability) {
this.symbol = symbol;
this.probability = probability;
- this.symbolFrequency = frequency;
- subNodeA = null;
- subNodeB = null;
+ rightChild = null;
+ leftChild = null;
this.leaf = true;
}
- private HuffmanNode(final HuffmanNode parentA, final HuffmanNode parentB) {
- subNodeA = parentA;
- subNodeB = parentB;
+ private HuffmanNode(final HuffmanNode rightChild, final HuffmanNode leftChild) {
+ this.rightChild = rightChild;
+ this.leftChild = leftChild;
}
- public static HuffmanNode constructWithSymbol(final HuffmanNode parentA, final HuffmanNode parentB, final int symbol) {
- final HuffmanNode node = new HuffmanNode(parentA, parentB);
+ public static HuffmanNode constructWithSymbol(final HuffmanNode rightChild, final HuffmanNode leftChild, final int symbol) {
+ final HuffmanNode node = new HuffmanNode(rightChild, leftChild);
node.symbol = symbol;
- node.leaf = (parentA == null && parentB == null);
+ node.leaf = (rightChild == null && leftChild == null);
return node;
}
@@ -41,10 +43,10 @@ public class HuffmanNode implements Comparable<HuffmanNode> {
}
public HuffmanNode traverse(final boolean queryBit) {
- if (subNodeA != null && subNodeA.bit == (queryBit ? 1 : 0))
- return subNodeA;
- if (subNodeB != null && subNodeB.bit == (queryBit ? 1 : 0))
- return subNodeB;
+ if (rightChild != null && rightChild.bit == (queryBit ? 1 : 0))
+ return rightChild;
+ if (leftChild != null && leftChild.bit == (queryBit ? 1 : 0))
+ return leftChild;
assert (false) : "Corrupted huffman tree";
return null;
@@ -63,10 +65,6 @@ public class HuffmanNode implements Comparable<HuffmanNode> {
return symbol;
}
- public long getSymbolFrequency() {
- return symbolFrequency;
- }
-
public int getBit() {
return bit;
}
@@ -79,39 +77,104 @@ public class HuffmanNode implements Comparable<HuffmanNode> {
return probability;
}
- public HuffmanNode getSubNodeA() {
- return subNodeA;
+ public HuffmanNode getRightChild() {
+ return rightChild;
}
- public HuffmanNode getSubNodeB() {
- return subNodeB;
+ public HuffmanNode getLeftChild() {
+ return leftChild;
}
- private static boolean treeNodeEquality(final HuffmanNode A, final HuffmanNode B) {
- if (A.leaf) {
- if (!B.leaf) {
+ /**
+ * Check if two huffman nodes are value equal and if their subtrees are also equal.
+ *
+ * @param nodeA First huffman node.
+ * @param nodeB Second huffman code.
+ * @return True if nodes and their subtrees are equal.
+ */
+ private static boolean treeNodeEquality(final HuffmanNode nodeA, final HuffmanNode nodeB) {
+ if (nodeA.leaf) {
+ if (!nodeB.leaf) {
return false;
}
- return A.symbol == B.symbol;
+ return nodeA.symbol == nodeB.symbol;
} else {
- if (B.leaf) {
+ if (nodeB.leaf) {
return false;
}
- if (A.bit != B.bit)
+ if (nodeA.bit != nodeB.bit)
return false;
- if ((A.subNodeA != null && B.subNodeA == null) || (A.subNodeA == null && B.subNodeA != null))
+ if ((nodeA.rightChild != null && nodeB.rightChild == null) || (nodeA.rightChild == null && nodeB.rightChild != null))
return false;
- if ((A.subNodeB != null && B.subNodeB == null) || (A.subNodeB == null && B.subNodeB != null))
+ if ((nodeA.leftChild != null && nodeB.leftChild == null) || (nodeA.leftChild == null && nodeB.leftChild != null))
return false;
- final boolean subTreeAResult = treeNodeEquality(A.subNodeA, B.subNodeA);
- final boolean subTreeBResult = treeNodeEquality(A.subNodeB, B.subNodeB);
+
+ assert (nodeA.rightChild != null) : "Current node is not leaf and right child must be set.";
+ assert (nodeA.leftChild != null) : "Current node is not leaf and left child must be set.";
+
+ final boolean subTreeAResult = treeNodeEquality(nodeA.rightChild, nodeB.rightChild);
+ final boolean subTreeBResult = treeNodeEquality(nodeA.leftChild, nodeB.leftChild);
return (subTreeAResult && subTreeBResult);
}
}
- public boolean treeEqual(final HuffmanNode opposite) {
- return treeNodeEquality(this, opposite);
+ /**
+ * Check if tree starting from this node is equal to one starting from otherRoot.
+ *
+ * @param otherRoot Other tree root node.
+ * @return True if both trees are value equal.
+ */
+ public boolean treeEqual(final HuffmanNode otherRoot) {
+ return treeNodeEquality(this, otherRoot);
+ }
+
+ /**
+ * Save current node and its children to binary stream.
+ *
+ * @param node Node to write to stream.
+ * @param bitStream Binary output stream.
+ * @throws IOException when fails to write to stream.
+ */
+ private void writeToBinaryStreamImpl(final HuffmanNode node, final OutBitStream bitStream) throws IOException {
+ if (node.isLeaf()) {
+ bitStream.writeBit(1);
+ bitStream.write(node.getSymbol());
+ } else {
+ bitStream.writeBit(0);
+ writeToBinaryStreamImpl(node.getRightChild(), bitStream);
+ writeToBinaryStreamImpl(node.getLeftChild(), bitStream);
+ }
+ }
+
+ /**
+ * Save huffman tree from this node to the binary stream.
+ *
+ * @param bitStream Binary output stream.
+ * @throws IOException when fails to write to stream.
+ */
+ public void writeToBinaryStream(final OutBitStream bitStream) throws IOException {
+ writeToBinaryStreamImpl(this, bitStream);
+ }
+
+ /**
+ * Read huffman tree from the binary stream.
+ *
+ * @param bitStream Binary input stream.
+ * @return Root of the huffman tree.
+ * @throws IOException when fails to read from stream.
+ */
+ public static HuffmanNode readFromStream(final InBitStream bitStream) throws IOException {
+ if (bitStream.readBit()) // Leaf
+ {
+ return HuffmanNode.constructWithSymbol(null, null, bitStream.readValue());
+ } else {
+ final HuffmanNode rightChild = readFromStream(bitStream);
+ rightChild.setBit(1);
+ final HuffmanNode leftChild = readFromStream(bitStream);
+ leftChild.setBit(0);
+ return HuffmanNode.constructWithSymbol(rightChild, leftChild, -1);
+ }
}
}
\ No newline at end of file
diff --git a/src/main/java/cz/it4i/qcmp/huffman/Huffman.java b/src/main/java/cz/it4i/qcmp/huffman/HuffmanTreeBuilder.java
similarity index 67%
rename from src/main/java/cz/it4i/qcmp/huffman/Huffman.java
rename to src/main/java/cz/it4i/qcmp/huffman/HuffmanTreeBuilder.java
index 4601e9725e484484ed5c460217f5938f1b309a7d..5daf0ae9782064ac07789aff49751d841f318535 100644
--- a/src/main/java/cz/it4i/qcmp/huffman/Huffman.java
+++ b/src/main/java/cz/it4i/qcmp/huffman/HuffmanTreeBuilder.java
@@ -1,19 +1,15 @@
package cz.it4i.qcmp.huffman;
-import cz.it4i.qcmp.io.InBitStream;
-import cz.it4i.qcmp.io.OutBitStream;
-
-import java.io.IOException;
import java.util.*;
-public class Huffman {
+public class HuffmanTreeBuilder {
private HuffmanNode root = null;
private HashMap<Integer, boolean[]> symbolCodes;
private HashMap<Integer, Double> symbolProbabilityMap;
private final int[] symbols;
private final long[] symbolFrequencies;
- public Huffman(final int[] symbols, final long[] symbolFrequencies) {
+ public HuffmanTreeBuilder(final int[] symbols, final long[] symbolFrequencies) {
assert (symbols.length == symbolFrequencies.length) : "Array lengths mismatch";
this.symbols = symbols;
this.symbolFrequencies = symbolFrequencies;
@@ -57,14 +53,14 @@ public class Huffman {
currentCode.add(bit == 1);
}
- if (currentNode.subNodeA != null) {
+ if (currentNode.rightChild != null) {
final ArrayList<Boolean> codeCopy = new ArrayList<Boolean>(currentCode);
- traverseSymbolCodes(currentNode.subNodeA, codeCopy);
+ traverseSymbolCodes(currentNode.rightChild, codeCopy);
inLeaf = false;
}
- if (currentNode.subNodeB != null) {
+ if (currentNode.leftChild != null) {
final ArrayList<Boolean> codeCopy = new ArrayList<Boolean>(currentCode);
- traverseSymbolCodes(currentNode.subNodeB, codeCopy);
+ traverseSymbolCodes(currentNode.leftChild, codeCopy);
inLeaf = false;
}
@@ -93,7 +89,7 @@ public class Huffman {
for (int sIndex = 0; sIndex < symbols.length; sIndex++) {
final double symbolProbability = (double) symbolFrequencies[sIndex] / totalFrequency;
symbolProbabilityMap.put(symbols[sIndex], symbolProbability);
- queue.add(new HuffmanNode(symbols[sIndex], symbolProbability, symbolFrequencies[sIndex]));
+ queue.add(new HuffmanNode(symbols[sIndex], symbolProbability));
}
return queue;
@@ -115,12 +111,7 @@ public class Huffman {
private HashMap<Integer, Double> createSortedHashMap(final HashMap<Integer, Double> map) {
final List<Map.Entry<Integer, Double>> list = new LinkedList<Map.Entry<Integer, Double>>(map.entrySet());
//Custom Comparator
- list.sort(new Comparator<Map.Entry<Integer, Double>>() {
- @Override
- public int compare(final Map.Entry<Integer, Double> t0, final Map.Entry<Integer, Double> t1) {
- return -(t0.getValue().compareTo(t1.getValue()));
- }
- });
+ list.sort((t0, t1) -> (-(t0.getValue().compareTo(t1.getValue()))));
//copying the sorted list in HashMap to preserve the iteration order
final HashMap<Integer, Double> sortedHashMap = new LinkedHashMap<Integer, Double>();
for (final Map.Entry<Integer, Double> entry : list) {
@@ -128,38 +119,4 @@ public class Huffman {
}
return sortedHashMap;
}
-
- private void encodeHuffmanNode(final HuffmanNode node, final OutBitStream bitStream) throws IOException {
- if (node.isLeaf()) {
- bitStream.writeBit(1);
- bitStream.write(node.getSymbol());
- } else {
- bitStream.writeBit(0);
- encodeHuffmanNode(node.getSubNodeA(), bitStream);
- encodeHuffmanNode(node.getSubNodeB(), bitStream);
- }
- }
-
- private static HuffmanNode decodeHuffmanNode(final InBitStream bitStream) throws IOException {
- if (bitStream.readBit()) // Leaf
- {
- return HuffmanNode.constructWithSymbol(null, null, bitStream.readValue());
- } else {
- final HuffmanNode nodeA = decodeHuffmanNode(bitStream);
- nodeA.setBit(1);
- final HuffmanNode nodeB = decodeHuffmanNode(bitStream);
- nodeB.setBit(0);
- return HuffmanNode.constructWithSymbol(nodeA, nodeB, -1);
- }
- }
-
-
- public void saveHuffmanTree(final OutBitStream bitStream) throws IOException {
- assert root != null : "The tree is not build.";
- encodeHuffmanNode(root, bitStream);
- }
-
- public static HuffmanNode readHuffmanTree(final InBitStream bitStream) throws IOException {
- return decodeHuffmanNode(bitStream);
- }
}