public static byte[] EncodeBytes(byte[] source)
{
var coder = new HuffmanCoder <byte>();
coder.Build(source);
var encoded = coder.Encode(source);
var freq = coder.GetFrequencies();
return(BitConverter.GetBytes((short)(freq.Length))
.Concat(ToByteArray(freq))
.Concat(ToByteArray(encoded))
.ToArray());
}
static byte[] SaveHuffman(int[] seq, string name)
{
var seqdiff = seq.Distinct().Diff((a, b) => b - a).ToArray();
var coder = new HuffmanCoder <int>();
coder.Build(seqdiff);
var encoded = coder.Encode(seqdiff);
var freq = coder.GetFrequencies();
var seqhuff = BitConverter.GetBytes((short)(freq.Length))
.Concat(HuffmanHelper.ToByteArray(freq))
.Concat(HuffmanHelper.ToByteArray(encoded))
.ToArray();
seqhuff.WriteToGzip(name + "-huff");
return(seqhuff);
}
public static byte[] DecodeBytes(byte[] encoded)
{
var count = BitConverter.ToInt16(encoded, 0);
var freq = new KeyValuePair <byte, int> [count];
int pos = 2;
for (int i = 0; i < count; i++)
{
var element = encoded[pos];
var elemFreq = BitConverter.ToInt32(encoded, pos + 1);
freq[i] = new KeyValuePair <byte, int>(element, elemFreq);
pos += 5;
}
var bits = new BitArray(encoded.Skip(pos).ToArray());
var coder = new HuffmanCoder <byte>();
coder.Build(freq);
return(coder.Decode(bits));
}