public static HuffmanPacker Load(BinaryReader reader)
	    {
	        var symbols = HuffmanTable.Load(reader);
	        var len = reader.Read7BitEncodedInt();
	        var offsets = new HuffmanTable[len];
	        for (int i = 0; i < len; i++)
	        {
                offsets[i] = HuffmanTable.Load(reader);
	        }
	        return new HuffmanPacker(symbols, offsets);
	    }
	    public HuffmanPacker(HuffmanTable symbols, HuffmanTable[] offsets)
		{
			this.symbols = symbols;
			this.offsets = offsets;
		}