private uint ConstructMask(int denominator)
{
MaskBits = BitUtilities.GetNumberBitsToRepresent(denominator);
uint retMask = 0;
for (int i = 0; i < MaskBits; i++)
{
retMask |= 1;
retMask <<= 1;
}
return(retMask >> 1);
}
private void DecodeBlock(BitReader readerIn)
{
int numCodedSymbols = readerIn.ReadInt(23);
//Change to use stack only if the output stream is non-seekable
//If it is seekable, then simply write the number of bytes that will be put into the stream
//Then seek backward, writing them one by one
Stack <int> symbolsStack = new Stack <int>();
AnsCodingTable decodeTable = AnsCodingTable.ReadTable(readerIn, EncryptionKey);
int bitCapacity = BitUtilities.GetNumberBitsToRepresent(decodeTable.Denominator);
AnsState internalsState = new AnsState(bitCapacity, null, 0);
internalsState.Underlying = readerIn.ReadUint(bitCapacity);
KeyValuePair <int, int> symbolRow;
for (int i = 0; i < numCodedSymbols; i++)
{
symbolRow = decodeTable.DecodePoint(internalsState.ToInt());
symbolsStack.Push(symbolRow.Key);
internalsState.Underlying = (uint)symbolRow.Value;
int bitsToRead = bitCapacity - internalsState.Contained;
for (int j = 0; j < bitsToRead; j++)
{
internalsState.PushLower(readerIn.ReadBit());
}
}
//Decoding finished...
BitWriter symbolWriter = new BitWriter(Output);
byte numBitsToWrite;
if (decodeTable.SymbolType == typeof(byte))
{
numBitsToWrite = 8;
}
else if (decodeTable.SymbolType == typeof(short))
{
numBitsToWrite = 16;
}
else
{
numBitsToWrite = 32;
}
while (symbolsStack.Count != 0)
{
int symbol = symbolsStack.Pop();
symbolWriter.WriteLong(symbol, numBitsToWrite);
}
}
public CodingTableStreamer(Dictionary <int, Fraction> frequencyDictionary)
{
int largestNumberBitsSymbol = 0,
largestNumberBitsFrequency = 0;
foreach (KeyValuePair <int, Fraction> pair in frequencyDictionary)
{
int numBitsSymbol = BitUtilities.GetNumberBitsToRepresent(pair.Key);
int numBitsFrequency = BitUtilities.GetNumberBitsToRepresent(pair.Value.Numerator);
if (numBitsSymbol > largestNumberBitsSymbol)
{
largestNumberBitsSymbol = numBitsSymbol;
}
if (numBitsFrequency > largestNumberBitsFrequency)
{
largestNumberBitsFrequency = numBitsFrequency;
}
NumFrequencies++;
}
LargestSymbolBits = largestNumberBitsSymbol;
CalculateType();
LargestFrequencyBits = largestNumberBitsFrequency;
FreqDict = frequencyDictionary;
}
private int CalculateContainedBits()
{
return(BitUtilities.GetNumberBitsToRepresent((int)Underlying));
}
