public bool Decode(StreamManipulator input)
{
try
{
lnum = input.GrabBits(5) + 257;
dnum = input.GrabBits(5) + 1;
blnum = input.GrabBits(4) + 4;
num = lnum + dnum;
lengths = new byte[19];
for (int i = 0; i < blnum; i++)
{
lengths[BL_ORDER[i]] = (byte)input.GrabBits(3, true);
}
blTree = new InflaterHuffmanTree(lengths);
lengths = new byte[num];
int index = 0;
while (index < lnum + dnum)
{
byte len;
int symbol = blTree.GetSymbol(input);
if (symbol < 0)
{
return(false);
}
if (symbol < 16)
{
lengths[index++] = (byte)symbol;
}
else
{
len = 0;
if (symbol == 16)
{
if (index == 0)
{
return(false); // No last length!
}
len = lengths[index - 1];
symbol = input.GrabBits(2, true) + 3;
}
else if (symbol == 17)
{
// repeat zero 3..10 times
symbol = input.GrabBits(3, true) + 3;
}
else
{
// (symbol == 18), repeat zero 11..138 times
symbol = input.GrabBits(7, true) + 11;
}
if (index + symbol > lnum + dnum)
{
return(false); // too many lengths!
}
// repeat last or zero symbol times
while (symbol-- > 0)
{
lengths[index++] = len;
}
}
}
if (lengths[256] == 0)
{
return(false); // No end-of-block code!
}
return(true);
}
catch (Exception x)
{
return(false);
}
}