public override IntField Decode(Stream input)
{
// Read size
int w = (int)input.ReadUInt32Optim();
int h = (int)input.ReadUInt32Optim();
// Read probabilities
ulong[] probs = CodecUtil.LoadFreqsCrappy(input, FieldcodeSymbols + 1);
// Read fields
ArithmeticSectionsCodec ac = new ArithmeticSectionsCodec(probs, 6);
ac.Decode(input);
var fields = new List <int[]>();
for (int i = 1; i <= 3; i++)
{
fields.Add(ac.ReadSection());
}
// Undo fieldcode
IntField transformed = CodecUtil.FieldcodeRunlengthsDe(fields, w, h, new RunLength01MaxSmartCodec(FieldcodeSymbols), this);
// Undo predictive transform
transformed.PredictionDeTransformDiff(Seer, 4);
transformed.ArgbFromField(0, 3);
return(transformed);
}