public byte[] Decode(Stream stream)
{
using (var ms = new MemoryStream())
{
var br = new BitReader(stream);
int value;
int i = 0;
int prevValue = -1;
byte lastChar = 0;
if (br.BitsRead + lookup.CodeLen <= br.BitsLength)
{
value = br.ReadBits(lookup.CodeLen);
lastChar = lookup.OutputText(lastChar, value, ms);
prevValue = value;
}
while (br.BitsRead < br.BitsLength)
{
if (lookup.Count >= 0xFFF)
{
lookup.Reset();
if (br.BitsRead + lookup.CodeLen <= br.BitsLength)
{
value = br.ReadBits(lookup.CodeLen);
lastChar = lookup.OutputText(lastChar, value, ms);
prevValue = value;
}
}
if (br.BitsRead + lookup.CodeLen <= br.BitsLength)
{
lookup.EnsureCodeLen();
value = br.ReadBits(lookup.CodeLen);
}
else
{
break;
}
if (value != lookup.Count)
{
lastChar = lookup.OutputText(lastChar, value, ms);
lookup.AppendChar(lastChar, prevValue);
}
else
{
lookup.AppendChar(lastChar, prevValue);
lastChar = lookup.OutputText(lastChar, value, ms);
}
prevValue = value;
}
return(ms.ToArray());
}
}
