public string Decode(BitArray code, out int codeLength)
{
var index = 0;
var length = BitArrayConverter.ConvertToInt(code, ref index, 32);
var dict = FrequencyDictionaryCoder.GetDictionary(code, ref index);
codeLength = code.Length - index;
return(TextDecode(code, index, dict, length));
}
private List <Pair <char, int> > BitArrayToListOfPairs(BitArray code)
{
var res = new List <Pair <char, int> >();
var index = 0;
while (index < code.Length)
{
var symbol = BitArrayConverter.ConvertToChar(code, ref index);
var number = BitArrayConverter.ConvertToInt(code, ref index, LengthOfNumber);
res.Add(new Pair <char, int>(symbol, number));
}
return(res);
}
public static Dictionary <char, int> GetDictionary(BitArray code, ref int index)
{
var res = new Dictionary <char, int>();
var cnt = BitArrayConverter.ConvertToInt(code, ref index, 8);
for (var _ = 0; _ < cnt; _++)
{
var symbol = BitArrayConverter.ConvertToInt(code, ref index, 16);
var newCode = BitArrayConverter.ConvertToInt(code, ref index, 32);
res.Add((char)symbol, newCode);
}
return(res);
}
public static Dictionary <BitArray, char> GetDictionary(BitArray code, ref int index)
{
var res = new Dictionary <BitArray, char>(new BitArrayComparer());
var cnt = BitArrayConverter.ConvertToInt(code, ref index, 8);
for (var _ = 0; _ < cnt; _++)
{
var symbol = BitArrayConverter.ConvertToInt(code, ref index, 16);
var length = BitArrayConverter.ConvertToInt(code, ref index, 5);
var newCode = new BitArray(length);
for (var i = 0; i < length; i++)
{
newCode[i] = code[index];
index++;
}
res.Add(newCode, (char)symbol);
}
return(res);
}
