// encoder
void Huffman::encode()
{
cout << "Begin encoding..." << endl;
cout << "Open file..." << endl;
inFile_.open(inFileName_.c_str(),ios::in);
cout << "Calculating frequency of all ascii chars..." << endl;
createNodeArray();
cout << "Done!" << endl;
inFile_.close();
cout << "Creating Priority-Queue..." << endl;
createPq();
cout << "Done!" << endl;
cout << "Creating Huffman-Tree..." << endl;
createHuffmanTree();
cout << "Done!" << endl;
cout << "Calculating Huffman-Code..." << endl;
calculateHuffmanCode();
cout << "Done!" << endl;
cout << "Saving to outputfile..." << endl;
saveToFile();
cout << "Done!" << endl;
cout << "Ecoding finished!" << endl;
}
bool huffmanPrintCode(Stream& in, Stream& out, bool verbose)
{
bool bOk = true;
// check for the binnary header
if(in.mode() == StreamRead && out.mode() == StreamWrite)
{
if(isHuffmanFile(in))
{ // An Encoded file
if(verbose)
{
fprintf(stdout, "huffmanPrintCode: encoded file\n");
}
uint32_t dataBytes;
HuffmanNode* root = readCodeTable(in, dataBytes);
assert(root);
SymbolEncoder SE;
SE.buildSymbolEncoder(root);
SE.printCodeTable(out);
bOk = true;
}
else
{
// A natural File
if(verbose)
{
fprintf(stdout, "huffmanPrintCode: natural file\n");
}
FrequencyTable freqTable;
SymbolEncoder SE;
freqTable.updateFreqTable(in);
calculateHuffmanCode(freqTable, SE);
SE.printCodeTable(out);
bOk = true;
}
}
else
{
bOk = false;
}
return bOk;
}
bool huffmanProcess(Stream& in, Stream& out, HuffmanDirection direction, bool verbose)
{
bool bOk = true;
if(direction == HuffmanEncode)
{
FrequencyTable freqTable;
SymbolEncoder SE;
if(verbose) fprintf(stdout, "Encode\n");
{
// Get the frequency of each symbol in the input file.
freqTable.updateFreqTable(in);
if(verbose) fprintf(stdout, "Input Size(%ld bytes)\n", freqTable.totalCount());
if(verbose) fprintf(stdout, "Nb symbols: %ld\n", freqTable.numberOfSymbols());
// Build an optimal table from the symbolCount.
bOk = calculateHuffmanCode(freqTable, SE);
double bitSize = 0.0;
double entropy = 0.0;
if(bOk)
{
computeAverageBitSize(SE, freqTable.totalCount(), bitSize, entropy, verbose);
// Scan the file again and, using the table
// previously built, encode it into the output file.
in.rewind( );
}
if(verbose) fprintf(stdout, "Writing code table (%lu symbols, %lu worlds)\n", freqTable.size(), freqTable.totalCount());
bOk = bOk ? SE.writeCodeTable(out, freqTable.totalCount()) : false;
if(bOk)
{
if(verbose) fprintf(stdout, "Encoding\n");
bOk = SE.encode(in, out, verbose);
}
// Print info
fprintf(stdout, "Encoded: nbSymbol: %ld, bitSize: %.2g, entropy: %.2g, nbBytes: %ld\n",
freqTable.numberOfSymbols(), bitSize, entropy, freqTable.totalCount());
}
}
else
{
if(verbose) fprintf(stdout, "Decode File");
unsigned int totalNbBytes = 0;
// Read the Huffman code table.
fprintf(stdout, "# Reading code table");
std::auto_ptr<const HuffmanNode> root(readCodeTable(in, totalNbBytes));
if(!root.get())
{
fprintf(stdout, "Error: cannot read code table\n");
bOk = false;
}
else
{
if(verbose) fprintf(stdout, "# Decoding (size: %u bytes)", totalNbBytes);
// Decode the file.
const HuffmanNode* p = root.get();
unsigned int remainingNbBytes = totalNbBytes;
unsigned int totalCountOfSymbols = 0;
while(remainingNbBytes>0 && in.isOpen())
{
const Byte byte = in.readByte();
Byte mask = 1;
while(remainingNbBytes>0 && mask)
{
p = (byte & mask) ? p->one() : p->zero();
mask <<= 1;
assert(p);
if(p->isLeaf( ))
{
out.writeSymbol(p->symbol());
totalCountOfSymbols++;
p = root.get();
--remainingNbBytes;
}
}
}
// this is not needed for the decode - Just for the info section
SymbolEncoder SE;
SE.buildSymbolEncoder(root.get());
double bitSize = 0.0;
double entropy = 0.0;
computeAverageBitSize(SE, totalCountOfSymbols, bitSize, entropy, verbose);
fprintf(stdout, "Decoded: nbSymbol: %ld, bitSize: %.2g, entropy: %.2g, nbBytes: %u\n",
SE.nbSymbol(), bitSize, entropy, totalNbBytes);
}
}
if(verbose) fprintf(stdout, "done (%d).\n", bOk);
return bOk;
}
